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1
Vdovin, Konstantin N., M. V. Shubina, and I. G. Shubin. "Investigation of Grey Cast Iron Microstructure Influence on its Heat Resistance." Solid State Phenomena 284 (October 2018): 332–37. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.332.
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Grey cast iron is one of the most common engineering materials used to make castings which work in thermal cycling. Under thermal cycling conditions, heat resistance is an important operational property of grey cast iron, which depends to the greatest extent on its structure – size and shape of the graphite inclusions, as well as the metal matrix composition. In this paper, the heat resistance of unalloyed grey cast iron with lamellar and compact graphite distributed in perlitic and perlitic-ferritic metal matrices was determined. The tests were carried out at temperatures of 500 – 800 °C. The results of the studies showed an insignificant difference of perlitic and perlitic-ferritic grey cast iron with lamellar graphite heat resistance. The heat resistance of perlitic ferritic grey cast iron with compact graphite is 16 – 48 % higher than the heat resistance of perlitic ferritic grey cast iron with lamellar graphite. Thus, when the shape of the graphite inclusions changed from lamellar to compact, a significant increase in the heat resistance of unalloyed grey cast iron occurred.
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Stoian, Elena Valentina, Vasile Bratu, Cristiana Maria Enescu, and Dan Nicolae Ungureanu. "Researches Regarding the Influence of Alloying Elements on the Mechanical Properties of Lamellar Graphite Cast Iron." Scientific Bulletin of Valahia University - Materials and Mechanics 16, no. 15 (2018): 11–16. http://dx.doi.org/10.1515/bsmm-2018-0012.
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Abstract Aim of the study is to present the technological process of obtaining cast iron with lamellar graphite for use in the manufacture of cylinder liners, and to identify the main alloying elements and track their influence on the mechanical properties of cast iron with lamellar graphite. Also paper presents analysis of 20 batches of cast iron with lamellar graphite, which are made of cylinder liners, in terms of chemical composition and the mechanical properties. After the analysis of the 20 castings of cast iron Fc 250 it is observed that: the increase in the carbon content shows a decrease of the tensile strength and hardness of the gray cast iron; the increase in silicon content shows a decrease in hardness and tensile strength. Decreasing the amount of graphite and especially the alloy of silicon iron lead to hardness increase 1% Si increases hardness by 50 HB). A statistical analysis has been performed on the data obtained that accounts for changes in alloying additions. A modeling and optimization of mechanical properties (tensile strength and hardness) was performed according to the percentages of carbon, silicon and manganese. Mathematical modeling found that the hardness and traction resistance of the cast iron decreased with the increase in carbon, silicon and manganese content.
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Danilov, V. N., and L. V. Voronkova. "INVESTIGATION OF THE POSSIBILITIES OF ULTRASONIC TESTING OF CAST IRON WITH LAMELLAR GRAPHITE USING STANDARD NORMAL PROBE." Kontrol'. Diagnostika, no. 259 (2020): 4–18. http://dx.doi.org/10.14489/td.2020.01.pp.004-018.
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Computer simulation of acoustic paths for medium – cast iron with lamellar graphite for standard normal probe of several types was carried out in order to study the effect of such medium on the characteristics of transmitted and received signals during ultrasonic testing. In the course of studies to calculate the attenuation coefficient of longitudinal waves in cast iron with lamellar graphite, due to their Rayleigh and phase scattering by graphite inclusions, the previously developed model was used. Comparison of the results of calculations of spectra and pulses of the recorded signals for two samples of cast iron with lamellar graphite confirmed the possibility of using the developed calculation model for a description of real physical phenomena adequate for the practice of ultrasonic testing. The ratio of the recorded signal and structural noise levels for different models of transducers, reflectors and characteristics of the controlled cast iron is estimated. Shown that increased attenuation of the longitudinal wave in cast iron in comparison with steel as a result of scattering by inclusions leads to higher level of this noise and can greatly reduce the signal-to-noise ratio in the detection of the reflected from the defect signals.
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Сканцев, Виталий, Vitaliy Skantsev, Денис Болдырев, et al. "Evolution of unregulated forms of graphite inclusions in graphitized structural cast iron." Bulletin of Bryansk state technical university 2015, no. 4 (2015): 11–18. http://dx.doi.org/10.12737/17141.
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The evolution influence of the graphite form (from a platetype form to a globular one) upon structural cast iron properties was analyzed and grounded, there were also considered cast iron peculiarities and prospects of their commercial application is estimated. For castings production the expediency of rational application of unregulated graphitized cast iron with the intermediate transitional morphology of graphite inclusions instead of grey iron high grades with lamellar graphite (GI 30, GI 35) and malleable cast iron is shown. The appropriate use substantiation of mentioned cast iron types taking into account their peculi-arities is shown.
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Salomonsson, Kent, and Anders E. W. Jarfors. "Three-Dimensional Microstructural Characterization of Cast Iron Alloys for Numerical Analyses." Materials Science Forum 925 (June 2018): 427–35. http://dx.doi.org/10.4028/www.scientific.net/msf.925.427.
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In this paper, we aim at characterizing three different cast iron alloys and their microstructural features, namely lamellar, compacted and nodular graphite iron. The characterization of microscopic features is essential for the development of methods to optimize the behavior of cast iron alloys; e.g. maximize thermal dissipation and/or maximize ductility while maintaining strength. The variation of these properties is commonly analyzed by metallography on two-dimensional representations of the alloy. However, more precise estimates of the morphologies and material characteristics is obtained by three-dimensional reconstruction of microstructures. The use of X-ray microtomography provides an excellent tool to generate high resolution three-dimensional microstructure images. The characteristics of the graphite constituent in the microstructure, including the size, shape and connectivity, were analyzed for the different cast iron alloys. It was observed that the lamellar and compacted graphite iron alloys have relatively large connected graphite morphologies, as opposed to ductile iron where the graphite is present as nodules. The results of the characterization for the different alloys were ultimately used to generate finite element models.
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Usol’tsev, A. A., N. A. Kozyrev, S. V. Knyazev, A. I. Kutsenko, and A. R. Mikhno. "On a possibility of replacing grey cast iron for manufacturing cast elements of electrolyzer gas collecting bell." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 77, no. 9 (2021): 1063–70. http://dx.doi.org/10.32339/0135-5910-2021-9-1063-1070.
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The main process leading to the destruction of the cast elements of gas-collection bell of electrolyzer, made of grey cast iron, is the oxidation of iron by oxygen, SO2 gas and sulfur vapors to form magnetite, hematite and pyrrhotin. The simultaneous formation of iron oxides and sulfides does not prevent further corrosion, since scale is formed with a loose structure that does not have protective properties. Reducing the length of the interfacial boundaries inside the material of the cast enables to reduce the rate of corrosion destruction, which can be achieved by modifying the cast iron to change the shape of graphite inclusions, i.e. obtaining high-strength cast iron with a spherical shape of graphite inclusions. However, the obtaining spherical graphite in cast iron using magnesium modification does not exclude the access of aggressive gases to the surface of the products and the possibility of their diffusion along the grain boundaries. It was shown that alloying can be an alternative, which leads not only to the exclusion of lamellar secretions of graphite in the structure of cast iron, but also to the formation of surface oxide layers based on the alloying element preventing the corrosion. Alloying with chromium gives cast iron high abrasive resistance due to the presence of a carbide component in the structure, as well as corrosion resistance due to the alloying of the metal base, heat resistance due to increasing the electrochemical potential of the metal base and creating a strong neutral oxide film on the surface of the castings, heat resistance, etc. An experimental comparative analysis of the corrosion resistance of cast iron used for manufacturing of gas collecting bell of electrolyzers showed that chromic cast iron ЧХ3 has a higher corrosion resistance than high-strength cast iron with spherical graphite ВЧ50 and much higher than grey cast iron with lamellar graphite. However, chromic cast iron ЧХ3 has low casting properties, is very sensitive to the cooling rate and has a large heterogeneity in structure, which makes it difficult to use it for the manufacture of gas collecting bell of electrolyzers.
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Holmgren, Daniel. "Modelling the Thermal Conductivity of Various Cast Irons." Key Engineering Materials 457 (December 2010): 318–23. http://dx.doi.org/10.4028/www.scientific.net/kem.457.318.
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The thermal conductivity of five predominately pearlitic grades of lamellar, compacted and spheroidal graphite iron have been modelled by means of existing models based on average field approximations. The model is based on the area fraction of different constituents and the width to length ratio of the graphite. The thermal conductivity of graphite in cast iron is derived by inverse modelling. These data are used in combination with experimental thermal conductivity values for a pearlitic matrix in order to model the thermal conductivity of various cast iron grades with good agreement. The calculations are executed for cast iron from room temperature up to 500°C.
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Devecili, Ahmet Oktay, and Rifat Yakut. "The Effect of Nb Supplement on Material Characteristics of Iron with Lamellar Graphite." Advances in Materials Science and Engineering 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/465947.
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In this experiment a cast iron alloy consisting of 0.019, 0.151, 0.431, and 0.646% niobium by weight was set and the microstructure solidification of iron with lamellar graphite was provided. These alloys were subjected to an abrasion test and chemical analyses of the microstructure were done by using scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). In addition to this, phase compositions were characterised by X-ray diffraction (XRD). Tests of mechanical strength, hardness, and tension were also applied to the alloys. The results of this experiment demonstrated that the addition of niobium to iron with lamellar graphite caused an increase in the abrasion resistance by 15%. This experiment shows that adding niobium improves the mechanical properties of grey cast iron.
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Timofeeva, Larisa, Sergey Timofeev, Liudmyla Voloshyna, and Maksym Kolesnyk. "Increasing the tribological properties of the sur-face layer of cast iron by treatment in the envi-ronment of overheated steam of aqueous solution." Bulletin of Kharkov National Automobile and Highway University, no. 94 (December 16, 2021): 123. http://dx.doi.org/10.30977/bul.2219-5548.2021.94.0.123.
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The formation of the surface layer of cast iron during the processing of cast iron in the environment of superheated steam of an aqueous solution of salts is considered. An ecologically cleaner method of chemical-thermal treatment is offered. The article considers the surface layer obtained in the environment of superheated steam of an aqueous solution of water-soluble salts of ammonium molybdic acid. The layer is formed on the surface of the matrix and around the graphite inclusions. The impact of temperature on the formation of a multilayer coating by increasing the temperature in contact with the metal surface is the dissociation of chemical compounds in solution, with the formation of atomic oxygen, sulfur, nitrogen, molybdenum. The formation of the surface layer occurred not only on a metal base, but also on the boundaries of graphite, both lamellar and globular, coming to the surface of the metal without breaking the solid layer. It is established that as a result of interaction of technological parameters of temperature, holding time and concentration of saturated medium graphite in the surface layer changes its shape, becoming spherical, although in the matrix it had a lamellar shape. It is multiphase and contains soft and hard structural components. Comparative studies have shown that the wear rate of untreated cast iron is much higher than that of treated cast iron, and reaches 0.8 ∙ 10-4 μm/km at a load of 400 N. This increases the wear resistance of cast iron and at the same time improves the workability reducing the coefficient of friction. The effect of the coating on the workability show that the stabilization of the friction moment occurs faster in samples with a multilayer coating. Thus, for gray cast iron with lamellar graphite, the stabilization time of the friction moment in a multilayer coating is 0.6 h compared with 2 h for a single layer coating; in high-strength cast iron it is, respectively, 5.2 and 6.3 hours.
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Sirenko, К. A., V. L. Mazur, and D. О. Derecha. "Dependence of hardness and other properties of gray iron on its carbon equivalent and degree of eutecticity." Metal and Casting of Ukraine 31, no. 2 (2023): 42–50. http://dx.doi.org/10.15407/steelcast2023.02.042.
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The chemical composition, carbon equivalent and properties of castings from unalloyed and low-alloyed gray irons with lamellar graphite of various grades from СЧ100 to СЧА400 were analyzed in accordance with DSTU 8833:2019. There is a reference to such cast iron in the technical conditions for brake pads made of composite materials (rubber mixtures), in particular, for the production of cast iron inserts. Other products for railway transport are also made from cast iron СЧ350, for example, the friction “Khanin wedge”. It is shown that in industrial batches of the “Khanin wedge”, cast from cast iron СЧ350, the hardness did not correlate either with the content of elements in the chemical composition of the cast iron, or with the carbon equivalent due to the narrow range of its values even within the cast iron of the same grade. According to DSTU 8833:2019, with an increase in the carbon equivalent in the possible regulated range of values (%) from 3.03 to 4.54, the Brinell hardness of HB monotonically decreases by approximately 1.54...1.57, and the coefficient of thermal conductivity increases by almost one and a half times. Reducing the sulfur content in the chemical composition from 0.20 to 0.05 % of CH350 cast iron significantly reduces the range of dispersion of the carbon equivalent. The parameters (mean values, mean square deviations and coefficients of variation) of the carbon equivalent and the degree of eutecticity of the chemical composition of cast irons with lamellar graphite of brands from СЧ100 to СЧА400 were determined by means of statistical tests using the Monte Carlo method. It is shown that due to the significant dispersion of the values of the carbon equivalent of the chemical composition, hardness, coefficient of thermal conductivity, strength, density, modulus of elasticity, linear shrinkage, heat capacity, coefficient of linear expansion of cast iron with lamellar graphite of grades from СЧ100 to СЧА400 according to DSTU 8833:2019, it is necessary from the specified list grades of cast iron to determine and regulate in the technical conditions for composite brake pads a specific grade of cast iron intended for the manufacture of inserts in such pads.
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Maj, M. "Fatigue Life Assessment of Selected Engineering Materials Based on Modified Low-Cycle Fatigue Test." Archives of Foundry Engineering 13, no. 1 (2013): 89–94. http://dx.doi.org/10.2478/afe-2013-0017.
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Abstract In this study, the mechanical tests were carried out on ductile iron of EN-GJS-600-3 grade and on grey cast iron of EN-GJL-250 grade. The fatigue life was evaluated in a modified low-cycle fatigue test (MLCF), which enables the determination of parameters resulting from the Manson-Coffin-Morrow relationship. The qualitative and quantitative metallographic studies conducted by light microscopy on selected samples of ductile iron with spheroidal graphite and grey cast iron with lamellar graphite (showing only small variations in mechanical properties,) confirmed also small variations in the geometrical parameters of graphite related with its content and morphological features.
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Karlina, Antonina, Viktor Kondratiev, Ivan Sysoev, Aleksandr Kolosov, Marina Konstantinova, and Elena Guseva. "Study of the effect of a combined modifier from silicon production waste on the properties of gray cast iron." Metal Working and Material Science 26, no. 1 (2024): 194–211. http://dx.doi.org/10.17212/1994-6309-2024-26.1-194-211.
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Introduction. During the metallurgical production of silicon, waste is generated that accumulates in dumps, causing harm to the environment. Disposal and recycling of solid waste from silicon production is especially important because They contain important chemical compounds (silicon dioxide, silicon carbide, carbon nanotubes) that can be used in other industries, which will bring greater economic value. Considering the possibilities for extracting these useful components from silicon production waste, it is necessary to bring processing technologies to the stage of widespread practical application. Therefore, the development of a special waste processing technology to obtain a useful product in the form of a composition of silicon dioxide and silicon carbide remains an urgent problem. Purpose of the work: to study the formation of the morphological form of graphite with the introduction of nano-modifiers from silicon production waste. The work examined samples of gray cast iron after modification with a combined modifier obtained from silicon production waste. The research methods are mechanical tests for statistical tension, analysis of the chemical composition and metallographic studies. Results and discussion. It was revealed that the mechanical properties of gray cast iron increased by 30-50% after modification with a combined modifier, compared with witness samples. The morphology of graphite is an important parameter affecting the properties of cast iron. It has been established that during the modification process the morphology of graphite changes from lamellar to vermicular. Specimens of gray cast iron with vermicular form of graphite have high strength values compared to specimens of gray cast iron with lamellar form of graphite. The presented results confirm the promise of the developed approach aimed at obtaining new classes of modifiers and products made of gray cast iron with a high range of mechanical properties.
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Sirenko, К. A., and V. L. Mazur. "Prediction of the mechanical properties of gray cast iron (probabilistic approach)." Metaloznavstvo ta obrobka metalìv 29, no. 3 (2023): 19–30. http://dx.doi.org/10.15407/mom2023.03.019.
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The article analyses the literature on the dependence of mechanical properties (tensile strength, hardness, etc.) of grey cast iron castings on the percentage of chemical elements in its composition and on the carbon equivalent, degree of eutecticity, and the ratio of carbon to silicon content. On the example of assessing the mechanical properties of cast iron with lamellar graphite, these dependencies are considered in the probabilistic aspect. It is emphasised that even within the same ranges of percentage of chemical elements in cast iron, as defined in standards or specifications, the values of its carbon equivalent, eutecticity, and the ratio of carbon to silicon content may be different. On the other hand, with different percentage ratios of chemical elements in the cast iron composition, the values of its carbon equivalent may be the same. It is shown that the conclusion about the presence or absence of correlation, in particular, between the hardness of castings and the carbon equivalent of the grey cast iron from which they are made, depends on the interval of variation of this argument. If the variation in the hardness of castings is significant and the interval for changing its carbon equivalent, calculated according to the chemical composition of cast iron specified in the standard for a particular casting product, is relatively short, the dependence of cast iron hardness on its carbon equivalent may not be evident. The disadvantage of the known empirical formulas intended for the approximate calculation of the tensile strength and hardness of cast iron based on its carbon element and eutecticity is the uncertainty of the choice of these indicators. It is proposed to use in such formulas the mathematical expectations (average values) of the carbon equivalent, eutecticity degree and the ratio of carbon to silicon content determined in the probabilistic approach using the Monte Carlo method. It is recommended that the distributions of chemical elements in grey cast iron within their intervals provided for in the standards be considered in accordance with the normal Gaussian law. Based on the information on the chemical composition and properties of grey cast iron with lamellar graphite smelted in accordance with the requirements of DSTU 8833-2019, the dependence of the carbon equivalent and the degree of eutecticity on the ratio of carbon to silicon content, as well as the strength and hardness of castings on these characteristics of the chemical composition of cast iron, have been identified. The formulas for determining the mechanical properties of grey cast iron with lamellar graphite have been calculated. Keywords: cast iron, casting, chemical composition, carbon equivalent, carbon to silicon ratio, degree of eutecticity, hardness, strength.
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Májlinger, Kornél, and Péter János Szabó. "Laser Treatment of Cast Iron Engine Cylinder Bore with Nanosecond Laser Pulses." Materials Science Forum 659 (September 2010): 319–24. http://dx.doi.org/10.4028/www.scientific.net/msf.659.319.
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The environmental and polluting materials emission standards in Europe are going to be always stricter, so in order to keep up with them, one of the largest European automotive manufacturer performs a laser treatment on the cylinder bores of their internal combustion engines. Due to the laser treatment, the near surface area of the cylinder bore becomes harder and more wear resistant, furthermore, due to the inhomogenity of the pearlitic matrix and graphite lamellae, oil reserving holes are formed. In our present work we investigated the laser treated layer of cast iron cylinder bores with lamellar graphite. Samples prepared with two different lasertypes and different energies were investigated on behalf of metallographic and functional aspects.
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Sommerfeld, A., and B. Tonn. "Theory of Graphite Nucleation in Lamellar Graphite Cast Iron." International Journal of Metalcasting 3, no. 4 (2009): 39–47. http://dx.doi.org/10.1007/bf03355457.
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VOLCHUK, V. M., N. V. KASHYNA, M. A. KOTOV, A. M. HAIDAR, and D. O. KASHYN. "CALCULATION OF MATERIAL QUALITY CRITERIA USING FRACTAL THEORY." Physical Metallurgy and Heat Treatment of Metals, no. 2 (101) (October 21, 2023): 20–28. http://dx.doi.org/10.30838/j.pmhtm.2413.040723.20.980.
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Problem statement. Changing the parameters of standard technology can significantly change the properties of rolled iron in a wide range of values. Regulatory and technical industry documentation regulates only the hardness indicators of cast iron rolls, and the requirements for mechanical characteristics and wear resistance are not indicated due to the influence of many technological parameters. Therefore, an important aspect is the prediction for quality indicators of cast iron due to the use of mathematical modeling, in particular the theory of fractals. Materials and methods. Cast iron rolls with a pearlite matrix were studied. The mechanical properties of the working area for cast-iron graded rolled rolls produced by OJSC “Dniprovskyi zavod protnykhnykh valkov”, Dnipro, were determined on standard equipment using INSTRON and CD-40 machines, PSV 5 pendular digger, Shore hardness tester. The microstructure of the rolls was analyzed at a magnification of 200 times. The results of the experiment. As a result of the experiment, it was established that the best among analyzed sensitivity of mechanical properties to dimensional characteristics of carbides is observed for fractal, information and correlation dimensions. Therefore, it is advisable to use these dimensional estimates of carbides in the future to predict the mechanical properties of the working zone for rolled iron with lamellar graphite. To predict the mechanical properties of rolled cast iron with lamellar graphite, it is advisable to use dimensional estimates of graphite and carbides with an increase in the structure of ´200. Conclusions. The analysis of the obtained results showed the promise of using the theory of multifractals for the quantitative assessment of the structural elements of rolled cast iron rolls with a complex geometric shape. This approach makes it possible to use statistical estimates of the dimensions of graphite and carbides to predict and correct the quality indicators of roll metal according to the obtained equations (3-6) along with traditional methods of quantitative metallography, which evaluate their geometric characteristics: shape, distribution, dimensions (length, diameter) and content.
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Baron, A. A., and L. V. Palatkina. "ON THE POSSIBILITY OF APPLYING A NEW PARAMETER OF THE PRIMARY STRUCTURE OF GRAY CAST IRON TO EVALUATE THE STRENGTH OF CASTINGS." IZVESTIA VOLGOGRAD STATE TECHNICAL UNIVERSITY, no. 10(245) (October 29, 2020): 66–71. http://dx.doi.org/10.35211/1990-5297-2020-10-245-66-71.
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The possibility of evaluating the strength of pearlite gray cast iron with lamellar graphite using the ratio of the area of the interdendritic eutectic phase to the perimeter of the primary austenite dendritic crystals was investigated. It is found that this parameter increases from 15,1 to 39,3 as the ultimate tensile strength of cast iron decreases from 300 to 180 MPa. The correlation coefficient for this relationship was 0.9.
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Tonn, Babette, Jacques Lacaze, and Stephanie Duwe. "Degenerated Graphite Growth in Ductile Iron." Materials Science Forum 925 (June 2018): 62–69. http://dx.doi.org/10.4028/www.scientific.net/msf.925.62.
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As part of a study devoted to the effect of trace elements on graphite degeneracy, near-eutectic ductile iron melts were prepared to which minute amounts of lead and of both lead and cerium were added. The melts were cast into an insulated Y4 mould, giving a solidification time of about 1 hour and a cooling time to room temperature of about 15 hours. In the thermal centre of the Pb containing sample graphite spheroids as well as intergranular lamellar graphite have been found. At the same location of the casting containing both Pb and Ce, exploded as well as chunky graphite could be observed, while the formation of intergranular lamellar graphite has been suppressed. Deep etching of the samples allowed reaching the following conclusions: i) intergranular graphite in the SG-Pb sample often, if not always, originates on graphite nodules and extends towards the last to freeze areas; ii) in one location of the SG-PbCe sample, chunky graphite strings were observed to originate on an exploded nodule, thus confirming the close relationship between these two forms of graphite. Because of the over-treatment in cerium of the SG-PbCe sample, other unusual degenerate graphite was observed which appears as coarse aggregates of "porous" graphite after deep etching.
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Belan, Juraj, Eva Tillová, Milan Uhríčik, and Lucia Pastierovičová. "Influence of Structural Parameters - the Shape of Graphite and Matrix on Change of Ultrasonic Wave Propagation Rate and Value of Attenuation in Graphitic Cast Irons." Production Engineering Archives 29, no. 1 (2023): 23–27. http://dx.doi.org/10.30657/pea.2023.29.4.
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Abstract Despite the tendency of the current industry, especially the automotive industry, it is to use modern, light and super-strong materials based on Al or HSLA steels, the application of classic materials such as cast iron still makes sense, especially concerning price and excellent castability. The article presents one of the possible ways of using the ultrasonic non-destructive method in quality control and simplification of the identification of the type of cast iron concerning the change of parameters of ultrasound propagation in materials. The main criteria for assessing the quality and determining the type of graphite cast iron were considered to be the rate of propagation of ultrasound - cL and the value of attenuation - α, which vary depending on the shape of the graphite and matrix. Graphitic cast irons with different graphite shapes (lamellar, vermicular, and globular shapes) and a matrix with different ferrite/perlite ratios were used as experimental material. Along with the ultrasonic tests, a metallographic analysis was also performed to quantify the microstructure of cast irons.
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Fourlakidis, Vasilios, Ilia Belov, and Attila Diószegi. "Strength Prediction for Pearlitic Lamellar Graphite Iron: Model Validation." Metals 8, no. 9 (2018): 684. http://dx.doi.org/10.3390/met8090684.
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The present work provides validation of the ultimate tensile strength computational models, based on full-scale lamellar graphite iron casting process simulation, against previously obtained experimental data. Microstructure models have been combined with modified Griffith and Hall–Petch equations, and incorporated into casting simulation software, to enable the strength prediction for four pearlitic lamellar cast iron alloys with various carbon contents. The results show that the developed models can be successfully applied within the strength prediction methodology along with the simulation tools, for a wide range of carbon contents and for different solidification rates typical for both thin- and thick-walled complex-shaped iron castings.
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Gubenko, S. I. "Diffusion crushing of graphite in integrated cast iron processing." Physical Metallurgy and Heat Treatment of Metals, no. 2 (93) (June 9, 2021): 26–32. http://dx.doi.org/10.30838/j.pmhtm.2413.270421.26.738.
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Purpose. It is necessary to investigate the possibility of crushing graphite inclusions in cast irons. The aim of the work was to study structural changes in graphite under explosive action followed by thermal cycling treatment of gray cast iron. Methods. Gray cast irons were subjected to explosive action (pressure is 90 GPa, the deformation rate is 100 s-1, the time is 10-6...10-7 s). Then the cast irons were subjected to thermal cycling: 950 °C, holding for 20 min, cooling with a furnace; 5 cycles. Metalographic ("Neophot-21"), micro-X-ray spectral ("Nanolab-7"), X-ray diffraction (DRON-2.0) research methods were used. Results. The features of diffusion crushing of graphite in cast irons with different types of metal matrix (ferritic, austenitic) and graphite shape (lamellar, spherical) have been studied. The features of structural changes in the cast iron matrix under explosive action, which determine the conditions for the transformation of graphite during subsequent thermal cycling, are discussed. It is shown that this process of diffusional crushing of graphite can be accompanied by local melting, which leads to the formation of regularly distributed dispersed particles of graphite. Scientific novelty. From the point of view of physical mesomechanics of plastic deformation, the processes of structural changes in the metal matrix of cast irons are considered. It is shown that nonequilibrium defect substructures of the cast iron matrix obtained during the explosion determine the features of diffusion crushing of graphite inclusions during subsequent thermal cycling. The conditions for diffusion crushing of graphite with reflow and in the solid-phase state have been established. Practical significance. It has been established that the complex processing of “explosive loading + thermal cycling” promotes crushing of coarse graphite inclusions, which is favorable for the mechanical and operational properties of cast irons. The use of the results obtained will make it possible to develop technologies for complex processing with regulated parameters of graphite inclusions, which will lead to an expansion of the field of application of gray cast irons. Keywords: cast iron; shock wave treatment; graphite; thermal cycling; stress relaxation
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Păcurar, Răzvan, Petru Berce, Ovidiu Nemeş, et al. "Cast Iron Parts Obtained in Ceramic Molds Produced by Binder Jetting 3D Printing—Morphological and Mechanical Characterization." Materials 14, no. 16 (2021): 4502. http://dx.doi.org/10.3390/ma14164502.
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Mechanical behavior and characteristics of two different types of materials: cast iron with lamellar graphite EN-GJL-250 and cast iron with spheroidal graphite EN-GJS-400-15 which were cast in ceramic molds using gravitational casting method has considered in this research. The ceramic molds were obtained by 3D printing method. First, a finite element analysis was developed to determine Tresca and von Mises stresses and the deformations of the ceramic molds under an applied pressure of 25 MPa. Samples were produced by gravitational casting using two types of cast iron materials. Mechanical tests were made using samples produced from these two types of materials and microstructure analysis evaluation of fractured zones was realized by scanning electron microscopy. Obtained results were finally used for designing, developing, and producing of one ‘hydraulic block’ of a railway installation by the Benninger Guss company of Switzerland.
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Lacaze, J., N. Valle, K. Theuwissen, J. Sertucha, B. El Adib, and L. Laffont. "Redistribution and Effect of Various Elements on the Morphology of Primary Graphite in Cast Iron." Advances in Materials Science and Engineering 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/638451.
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It has been shown repeatedly that many elements present as traces or at low level can affect graphite shape in cast irons. As part of a long term project aimed at clarifying the growth and the alteration of spheroidal graphite, a study on the effect of a few elements (Cu, Sn, Sb, and Ti) on primary graphite growth was undertaken and analysed with reference to an alloy without any such additions. This work was performed by remelting alloys in graphite crucibles thus saturating the melt in carbon and enabling primary graphite to grow by controlled cooling of the melt above the eutectic temperature. Primary graphite growth in the reference alloy was observed to be lamellar, while the added elements were found to affect bulk graphite and to modify its outer shape, with Sb leading eventually to rounded agglomerates together with wavy lamellae. Secondary ion mass spectrometry was used to analyze the distribution of elements, and no build-up of trace elements at the graphite surface could be observed. Instead, it is established that the perturbation of bulk graphite is associated with inhomogeneous distribution of metallic elements inside graphite precipitates.
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Masafi, Mohammad, Heinz Palkowski, and Hadi Mozaffari-Jovein. "Microstructural Properties of Particle-Reinforced Multilayer Systems of 316L and 430L Alloys on Gray Cast Iron." Coatings 13, no. 8 (2023): 1450. http://dx.doi.org/10.3390/coatings13081450.
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Gray cast iron (GJL) is known for its excellent damping property and high thermal conductivity, thanks to its unique lamellar graphite and pearlite structure. In a recent study, laser metal deposition (LMD) was explored as a potential process to enhance the corrosion resistance and wear mechanism of this tribological system. The focus was on laser cladding of gray cast iron using two different of stainless-steel materials, namely 430L and 316L, combined with TiC and WC particles. To create the samples, a multilayer coating system was employed. A comparative analysis of the microstructures was performed to understand the interaction of the laser beam with the material (composite materials). Surface properties were then characterized using light microscopy and electron microscopy (SEM) before and after subjecting the samples to a shock corrosion test, simulating automotive conditions. Additionally, phase analyses were performed at the interfaces between the coatings and the substrate, with particular attention given to the behavior of the graphite lamellae at these interfaces. This study aims to provide valuable insights into the potential improvements that can be achieved through laser cladding on gray cast iron, specifically in terms of corrosion resistance and wear mechanisms. By analyzing the microstructures and surface properties, researchers can gain a better understanding of the performance and durability of the coated samples.
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Lalazarova, Nataliia, Оlga Afanasieva, Olena Popova, and Oleksiy Dmytrenko. "Increasing wear resistance of the protective sleeve of the centrifugal pump made of gray cast iron by surface hardening." Bulletin of Kharkov National Automobile and Highway University, no. 94 (December 16, 2021): 103. http://dx.doi.org/10.30977/bul.2219-5548.2021.94.0.103.
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One of the weak spots that reduce the guaranteed operating time of centrifugal pumps is the assembly that includes the seal and protective sleeves. The main purpose of the bushings in the rotor kit is to protect the shaft from corrosion, erosion and wear. The sleeve operates under abrasive wear conditions by packing elements and abrasive particles that get into the liquid pumped by the pump. The protective sleeves made of gray cast iron do not meet the service life in connection with accelerated surface wear. Goal. The purpose of the work is to ensure high wear resistance of cast iron pump parts by heat treatment. Method. The chemical composition was determined on a portable laser analyzer Laser Z200 C +. The structure was studied using an optical microscope. The wear was investigated by the roller-block method on a friction machine. Surface quenching was carried out with a high-frequency lamp generator in a single-turn inductor. Results. The microstructure of gray cast iron as cast consists of pearlite, ferite, double phosphide eutectic and inclusions of lamellar graphite. Microhardness of small-lamellar pearlite is Н50 = 1550–2220 MPa, microhardness of phosphide eutectic is Н50 = 6500–8000 MPa. Surface induction quenching by high-frequency currents followed by low tempering is an effective way to increase the wear resistance of cast iron products of small cross-section and does not cause warping. Cast iron for surface quenching should have a pearlite structure, and graphite should be contained in the form of small inclusions. The optimal heating temperature for induction hardening was determined as 900 °С, which made it possible to obtain the microstructure of the hardened layer – martensite, double phosphide eutectic and graphite. Scientific novelty. The developed modes of surface quenching make it possible to preserve a double phosphide eutectic in the structure of the surface layer, which makes it possible to obtain high hardness and wear resistance of the hardened layer. Practical significance. Surface induction quenching with low tempering of cast gray iron increased its wear resistance by 2,4 times. The previous normalization had practically no effect on the durability of cast iron, since its structure contains less than 10% ferrite.
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Gumienny, G., L. Klimek, and B. Kurowska. "Effect of the Annealing Temperature on the Microstructure and Properties of Ausferritic Nodular Cast Iron." Archives of Foundry Engineering 16, no. 3 (2016): 43–48. http://dx.doi.org/10.1515/afe-2016-0047.
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Abstract The paper presents the microstructure and selected properties of ausferritic nodular cast iron annealed at the temperature 520 and 550°C. This choice was dictated by the temperatures used in the practice of nitriding. Nodular graphite in cast iron was obtained with use of Inmold process. Cast iron containing molybdenum and copper ensuring obtaining an ausferrite in the cast iron matrix without the use of heat treatment of castings was tested. The effect of annealing temperature on the microstructure and the kind of fracture of the ausferritic nodular cast iron was presented. The effect of an annealing temperature on hardness, impact strength and the microhardness of ausferritic nodular cast iron matrix was shown too. The lamellar structure of phases in the cast iron matrix after annealing has been ascertained. There has been an increase in hardness of an annealed cast iron and microhardness of its matrix. The reduction in the impact strength of the cast iron annealed at 520 and 550°C was approximately 10-30%. Both an increase in the hardness of cast iron as well as an decrease in its impact strength is probably due to the separation of secondary carbides during the heat treatment.
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Szymczak, T. "The Silumin Coat Structure on Alloy Ductile Iron." Archives of Foundry Engineering 13, no. 1 (2013): 119–24. http://dx.doi.org/10.2478/afe-2013-0023.
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Abstract The work presents the research results of the silumin coat structure applied on the carbidic alloy ductile iron with the metal matrix: pearlitic, bainitic and martensitic. The coats were made in the AlSi5 silumin bath at the temperature tk = 750±5°C. The holding time of cast iron element in the bath was τ = 180s. Irrespective of the kind of tested ductile iron the obtained coat consisted of three layers with a different phase composition. The first layer from the cast iron ground “g1`” is built from Fe4CSi carbide which contains selected alloy additives of the cast iron. On it the second layer “g1``” crystallizes. It consists of the AlFeSi inter-metallic phase which can appear in its pure form or contain a small quantity of the alloy additives of the cast iron. The last external part of the layer “g2” mainly consists of the hypo-eutectic phases of silumin. The AlFeSi inter-metallic phases in the form of free precipitations with a lamellar or faceted morphology can also appear there. These phases also can contain a small quantity of the alloy additives of the cast iron. More than that, in all the layers of the coat there are graphite precipitations. The phenomenon of graphite movement to the coat is caused by intensive dissolving of the cast iron element surface by the aluminum of the silumin bath.
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Vavro, Jan, Ján Vavro, Petra Kováčiková, Peter Kopas, Marián Handrik, and Radka Bezdedová. "Numerical Analysis of Stress States for Graphitic Cast Iron Structures." Applied Mechanics and Materials 611 (August 2014): 252–55. http://dx.doi.org/10.4028/www.scientific.net/amm.611.252.
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The presented work is focused on the analysis of stress distribution around the graphitic particles in microstructure of ductile cast iron with the spheroidal shape of graphite (SGCI) and grey cast iron with the lamellar shape of graphite (LGCI). The analysis was made with help of the finite element method in the software system ADINA.v.8.6.2. On the basis of the real structure, the finite element method was used for creation of the model which was subsequently used for calculation of the distribution of stress in the material structure. The input data for numerical analysis were obtained on the basis of evaluation of the structure with help of image analysis. The numerical analysis proved that graphitic particles in the matrix cause the accumulation of stress and the distribution of given stress depends on the shape of the graphitic particles.
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Ya, Bin, Shengchen Ji, Linggang Meng, et al. "Effect of Ultrasonic Treatment on Microstructure and Properties of Gray Cast Iron." Journal of Physics: Conference Series 2553, no. 1 (2023): 012050. http://dx.doi.org/10.1088/1742-6596/2553/1/012050.
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Abstract The effect of ultrasonic treatment on the microstructure and properties of gray cast iron was studied. The samples were analyzed by metallographic microscope, scanning electron microscope, Brinell hardness tester, electronic universal testing machine, etc. The results showed that ultrasonic treatment could improve the pearlite content in the microstructure. After ultrasonic treatment, the tensile strength of gray cast iron can be improved to 266 MPa, which is 11.60% higher than that of the samples without ultrasonic treatment. Ultrasonic treatment can refine the size of graphite, which can reduce the stress concentration. In addition, the pearlite lamellar spacing can also be reduced, which is the main reason for improving the mechanical properties of gray iron.
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Vavro, Jan, Ján Vavro, and Petra Kováčiková. "Distribution of Stress around the Graphitic Particles in Cast Iron Microstructure." Applied Mechanics and Materials 486 (December 2013): 20–25. http://dx.doi.org/10.4028/www.scientific.net/amm.486.20.
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The given work is focused on the analysis of the distribution of stress around graphitic particles in microstructure of the ductile cast iron with the spheroidal shape of graphite (SGCI) and grey cast iron with the lamellar shape of graphite (LGCI). The analysis was made with help of finite element method in the software system ADINA.v.8.6.2. On the basis of the real structure, the finite element method was used for creation of the model which was subsequently used for calculation of the distribution of stress in the material structure. The input data for numerical analysis were obtained on the basis of evaluation of the structure by help of image analysis. The numerical analysis proved that the graphitic particles in the matrix cause the accumulation of the stress and the distribution of the given stress depends on the shape of the graphitic particles.
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König, Mathias, Ingvar L. Svensson, and Magnus Wessen. "The Influence of Alloying Elements on Chill Formation in CGI." Key Engineering Materials 457 (December 2010): 126–31. http://dx.doi.org/10.4028/www.scientific.net/kem.457.126.
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The influence of alloying elements on the chill formation in Compacted Graphite Iron (CGI) is investigated. Chill wedges cast in an industrial foundry were used to investigate the chill formation. A total number of 19 chemical compositions were studied, including three trials of varying nodularity treatment level; four trials of varying copper content; four trials of varying silicon content; four trials of varying tin content and four trials of varying carbide promoter content. Three wedges were cast for each alloy composition, of which one was used for measuring the temperature at three different heights in the wedge. Contrary to some previous reports, the results indicate that low-nodularity CGI is not more prone to chill formation (columnar white) than high-nodularity CGI. Trends regarding the effect of alloying elements on chill formation are shown to generally be in agreement with previous work on spheroidal graphite iron and lamellar graphite iron. Most of the samples also show carbide formation in centre line areas of the wedge (inverse chill), this occurrence is also discussed in the paper.
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Sandomirskii, S. G. "ASSESSMENT OF RANGES OF POSSIBLE CHANGE OF TEMPORARY RESISTANCE OF CAST IRON WITH LAMELLAR AND FLAKED GRAPHITE ON THEIR HARDNESS." Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no. 2 (July 4, 2017): 40–45. http://dx.doi.org/10.21122/1683-6065-2017-2-40-45.
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The analysis of ranges of possible change of temporary resistance of sB of castings from ductile and gray cast iron is carried out. The analytical description of ranges of change of sВ depending on casting BH hardness is developed. It is shown that the range of change of sВ of pig-iron castings, wider in comparison with steel, with the measured hardness of BH is caused variations of forms and the amount of graphite inclusions at the considered classes of cast iron and influence of thickness of a wall of casting from gray cast iron on dependence of sВ (HB). The result is intended for determination of the guaranteed casting size sВ without her destruction, when there is no information on sВ of check test pieces.
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YAKUT, Rifat, and Ömer ÇİFTÇİ. "Investigation of the microstructure, hardness, and compressive properties of TaC-reinforced lamellar graphite cast irons." European Mechanical Science 7, no. 2 (2023): 56–62. http://dx.doi.org/10.26701/ems.1213039.
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Tantalum Carbide (TaC) reinforcement was made to lamellar graphite (gray) cast irons that were produced in the physical conditions of a foundry at reinforcement ratios of 0%, 0.025%, 0.155%, and 0.285%. Samples complying with standards were prepared using the TaC-reinforced lamellar graphite (gray) cast iron alloys that were produced, and Brinell hardness tests, compressive strength tests, and microstructural analyses were conducted. According to the test results, the highest average Brinell hardness value was found as 231 HB in sample A which was reinforced at a ratio of 0.025%. In general, as the reinforcement ratio increased, there was an increase in the hardness test measurement results. The highest average compressive strength value was found as 949 MPa in sample C which was reinforced at a ratio of 0.285%. In general, as the reinforcement ratio increased, there was an increase in the compressive strength values. The results of the microstructural analyses showed that the reinforcement material was dispersed into the matrix.
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Bourahima, Fazati, Anne Laure Helbert, Vincent Ji, et al. "Optimization of Microstructural Evolution during Laser Cladding of Ni Based Powder on GCI Glass Molds." Key Engineering Materials 813 (July 2019): 185–90. http://dx.doi.org/10.4028/www.scientific.net/kem.813.185.
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In glass industry, laser cladding is an innovative surfacing technique allowing to deposit a layer of nickel to protect glass mold against corrosion, abrasion and thermal fatigue. This method (powder fusion by projection), well known in additive manufacturing represents a real technological leap for the glass industry. But during laser cladding of Ni-based powder on gray cast iron, cracks can be observed for some process conditions. These cracks are often due to the Heat Affected Zone that creates structural stresses linked to the development of a martensitic structure in the ferritic matrix of the lamellar graphite cast iron. The aim of this work is to observe the impact of laser cladding (without substrate pre-heating usually employed to limit cracking) on the coating behavior but also on the flake-graphite cast iron substrates. The microstructure and the mechanical properties were studied (SEM and microanalysis, microhardness) around the interface cladding/substrate. Also, the impact of the processing parameters (power P (1500-2300 W), scanning speed v (2.5-10 mm/s) and powder feeding rate PFR (24.5-32.5 g/min) was studied by using the ANOVA (ANalysis Of VAriance) technique. It has been observed that laser cladding on graphite cast iron is possible without cracks by limiting the linear energy induced by the process. Also, an optimization of the processing parameters (P, v, PFR) in order to obtain the industrial expected geometry of the coating has been proposed.
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Lacaze, Jacques, Yannick Thébault, Alexandre Freulon, and Wilson Luiz Guesser. "Effect of Cooling Rate on the Eutectoid Transformation in Compacted Graphite Cast Iron." Materials Science Forum 925 (June 2018): 12–19. http://dx.doi.org/10.4028/www.scientific.net/msf.925.12.
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Differential thermal analysis has been used to characterize the effect of cooling rate on the eutectoid transformation of a compacted graphite iron. The samples were machined out from an as-cast thermal cup, austenitized at 950°C and then cooled to room temperature at various rates within the range 1−55.5°C/min. It was found that even at the highest investigated cooling rate, significant amounts of ferrite could be observed. When comparing the microstructure before and after Nital etching on samples cooled at intermediate cooling rates, it appeared that ferrite formed preferentially along the worms. This is discussed in terms of graphite shape and microsegregation and this latter seems prevalent. Finally, analysis of the thermal records was performed to characterize the temperatures for the start of the stable and metastable eutectoid reactions which confirms the eutectoid transformation sets up in compacted graphite irons as in lamellar and spheroidal graphite irons.
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Konstantinova, Marina V., Elena A. Guseva, and Natalia A. Astafeva. "The Use of Silicon Production Waste as an Effective Additive in the Manufacture and Machining of Various Materials." Materials Science Forum 1052 (February 3, 2022): 448–53. http://dx.doi.org/10.4028/p-5k645l.
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The article describes the results of experiments on the use of silicon production waste as an additive that improves the structure and properties of materials and the efficiency of welding process. The flotation technology can be used to separate gas cleaning dust, which is a silicon production waste product, into commercial products. The chamber product, containing ultrafine silica, was used as a modifying additive in concrete. It improved its structure and increased its strength compared to the samples without additives. The modifier made from chamber products introduced into gray cast iron made it possible to obtain graphite of a more favorable shape as compared to the lamellar form of graphite in traditional gray cast iron. Its strength increased. The experimental results on the welding process with an activating flux, which includes ultrafine silica isolated from the metallurgical waste, are presented. The activating flux improved the penetrating ability of the welding arc by 1.5-3 times, the energy consumption decreased by 30-50%.
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Ignaszak, Zenon. "Study on Data Base of Modeling Concerning Casting Phenomena in Cast-Iron-Mould Simulation Systems." Key Engineering Materials 457 (December 2010): 305–11. http://dx.doi.org/10.4028/www.scientific.net/kem.457.305.
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In the foundry processes the hard modeling based on physical-mathematical formula is burdened with simplifications resulting from both: knowledge level on description of particular phenomena and level of theirs complexity. Trends observed in modeling of foundry processes and expectations of users compared with creators’ up-grades propositions are discussed. The author presents real possibilities of efficient modeling validation considering that limits of multiphysics/multiscale modeling exist for massive cast-iron castings, including the zones infected by degenerated structure (e.g. chunky graphite, dross inclusions). The model validation demands experimental-simulation studies. In the paper also the stress grid castings made of lamellar cast-iron are presented as an example of experimental model validation including the thermomechanical properties of cast-iron and furan mould and applying special Hot Distortion (HDplus®) tests of this sand. The validation of thermo-mechanical model was carried out with the use of Comsol system and chosen foundry simulation code.
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Hernando, Juan Carlos, and Attila Diószegi. "On the Primary Solidification of Compacted Graphite Iron: Microstructure Evolution during Isothermal Coarsening." Materials Science Forum 925 (June 2018): 90–97. http://dx.doi.org/10.4028/www.scientific.net/msf.925.90.
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It is widely accepted that in most commercial hypoeutectic alloys, both static mechanical properties and feeding characteristics during solidification, are extremely linked to the coarseness of the primary phase. It is therefore of critical importance to provide tools to control and predict the coarsening process of the dendritic phase present in hypoeutectic melts. The characterization of the primary phase, a product of the primary solidification, has traditionally been neglected when compared to the eutectic solidification characterization in cast iron investigations. This work presents the morphological evolution of the primary austenite present in a hypoeutectic compacted graphite cast iron (CGI) under isothermal conditions. To that purpose, a base spheroidal graphite cast iron (SGI) material with high Mg content is re-melted in a controlled atmosphere and reversed into a CGI melt by controlling the Mg fading. An experimental isothermal profile is applied to the solidification process of the experimental alloy to promote an isothermal coarsening process of the primary austenite dendrite network during solid and liquid coexistence. Through interrupted solidification experiments, the primary austenite is preserved and observed at room temperature. By application of stereological relations, the primary phase and its isothermal coarsening process are characterized as a function of the coarsening time applied. The microstructural evolution observed in the primary austenite in CGI and the measured morphological parameters show a similar trend to that observed for lamellar graphite cast iron (LGI) in previous investigations. The modulus of the primary austenite, Mγ, and the nearest distance between the centre of gravity of neighbouring austenite particles, Dγ, followed a linear relation with the cube root of coarsening time.
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Holmgren, Daniel, and Martin Selin. "Regression Model Describing the Thermal Conductivity of Various Cast Irons." Materials Science Forum 649 (May 2010): 499–504. http://dx.doi.org/10.4028/www.scientific.net/msf.649.499.
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The thermal conductivity of various grades of pearlitic cast iron has been modelled with good results by means of regression analysis. The experimental thermal conductivity data, which the modelling is based on, were obtained by the laser flash method. The microstructure was investigated by digital image analysis combined with a colour etching technique. The model developed takes the carbon content, the silicon content, the nodularity as well as the fraction of cementite into consideration. The graphite morphologies of the samples investigated were lamellar, compacted and spheroidal.
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Cofiño-Villar, Alberto, Florentino Alvarez-Antolin, and Juan Asensio-Lozano. "Enhancement of the Quality of the Shell-Core Bond Interface in Duplex Work Rolls Manufactured by Centrifugal Casting Used in Hot Strip Mills." Materials 12, no. 8 (2019): 1304. http://dx.doi.org/10.3390/ma12081304.
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To ensure the formation of a sound shell-core bond interface free of defects between the shell and the core in work rolls used in the finishing stands of hot strip mills, a complete fusion of this interface must be achieved, avoiding excessive mixing of the two components and the formation of hard, fragile microstructures. The shell is made of white cast iron, alloyed with Ni and Cr, and the core is manufactured of grey cast iron spheroidal graphite in a pearlitic matrix. It is thus advisable to inoculate the shell with 0.6 kg/T SiCaMn, as this promotes discontinuity in the carbide network and leads to an increase in the impact toughness of the bond interface. Furthermore, inoculation of the shell with FeSi-La should be avoided, as this inoculant leads to an increase in graphite counts, promoting it with a lamellar morphology at the edge of the bond and hence reducing the impact toughness in this interface. Addition of Mg to the shell has been found to produce an increase in hardness in the regions adjacent to the bond interface.
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Kayali, Yusuf, Yelda Akcin, Ersan Mertgenc, and Barış Gokce. "Investigation of kinetics of borided ductile and lamellar graphite cast iron." Protection of Metals and Physical Chemistry of Surfaces 53, no. 1 (2017): 127–32. http://dx.doi.org/10.1134/s2070205117010105.
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Zimáková, J., T. Binar, P. Šafl, and P. Čudek. "Failure mechanism in the pearlite structure with lamellar graphite due to temperature." Journal of Physics: Conference Series 2382, no. 1 (2022): 012015. http://dx.doi.org/10.1088/1742-6596/2382/1/012015.
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Critical operating temperature can be determined for the machine components that form the key functional part of the device. This article describes a change of the failure mechanism in the material of an engine, where the material structure consists of fine pearlite layers with lamellar graphite equivalent to grey cast iron. The mechanical properties of this material influence not only the layers formed by the perlite, but also the lamellar graphite acting as a stress concentrator. To assess the failure mechanism in the material, a fractographic analysis of the fracture areas was performed after the impact test. The range of test temperatures at which the impact test was performed on the test specimens with notch ranged from -80°C to +180°C. The occurrence of brittle fracture was detected at the low temperatures by cleavage along and over the planar layers of the lamellar graphite. The brittle fracture initiation at the higher temperatures was observed by cleavage in the basic layer of the perlite. Depending on the failure mechanism of the test specimens fracture area, critical temperatures were determined, in which the measured value of the notch toughness decreased. Regression of temperature dependence of notch toughness allows very precise quantification of this decrease.
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Sumpena, Sumpena, Hb Sukarjo, Wardoyo Wardoyo, and Soksono Singgih Pramana. "Analisa Kekerasan dan Keausan Cylinder Sleeve dari Besi Cor Kelabu FC250 Hasil Sand Mold Casting." Jurnal Engine: Energi, Manufaktur, dan Material 5, no. 2 (2021): 97. http://dx.doi.org/10.30588/jeemm.v5i2.944.
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<p><em>The Cylinder sleeve is an engine component that is mounted on the cylinder block which functions as a piston glide base. The cylinder sleeve is made of FC250 gray cast iron. FC250 is a gray cast iron that has lamellar graphite with a tensile strength of at least 250 MPa. This study aims to determine the mechanical properties of hardness and wear of the Cylinder Sleeve made of gray cast iron FC250. The method used in this research is gray cast iron which is cut with a length of 5.5cm, thickness 0.7cm, height 0.7cm which is formed according to the standard size of the hardness and wear test. The tests carried out include testing brinell hardness and wear. The results showed that the lowest hardness value was 134.63BHN and the highest hardness value was 191.43BHN. The increase in hardness values is influenced by the carbon content that cannot be spread evenly, which is followed by a fast cooling rate. The results of the wear test obtained the lowest price of 0.00017mm³/kg.m and the highest wear price of 0.00028 mm³/kg.m.</em></p><p><em><br /></em></p>
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Shawki, G. S. A., and S. A. R. Naga. "On the Mechanics of Grey Cast Iron Under Pure Bending." Journal of Engineering Materials and Technology 108, no. 2 (1986): 141–46. http://dx.doi.org/10.1115/1.3225851.
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This paper presents the results of experiments conducted on lamellar graphite grey cast iron of rectangular section subjected to pure bending. Strain measurements confirm the traditional speculation that plane sections remain plane under strain. Owing to the nonlinear relationship between stress and strain, however, the neutral axis of a loaded specimen is shown to shift away from the centroidal axis. This shift is evidently amplified with increased loading. A computer program is herein specially devised for calculating the shift in neutral axis through satisfaction of the conditions of equilibrium together with checking for possible crack initiation at the extension side. While the simple flexural formula holds very nearly true for the compression side, it fails, however, to predict stresses on the extension side, the situation being further aggravated by higher bending moments. The apparent high bending strength of grey cast iron is fully accounted for.
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Sirenko, К. A. "Directions for the development of a methodology for regulating the chemical composition and properties of cast iron in foundry production based on a probabilistic approach." Metaloznavstvo ta obrobka metalìv 29, no. 4 (2023): 23–33. http://dx.doi.org/10.15407/mom2023.04.023.
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From the standpoint of systemic and structural-functional approaches, the state and prospects of development of the methodology for regulating and predicting the chemical composition and mechanical properties of grey synthetic cast iron intended for casting production are analysed. Attention is focused on the key intersections of the technological process of manufacturing castings for critical applications. The features, disadvantages, and advantages of the known methods for calculating the charge and adjusting the percentage of chemical elements in the cast iron composition directly during its melting are considered. Ways to take into account the instability of the chemical composition of scrap metal, ferroalloys, and other materials when forming the charge to ensure the quality of pig iron in accordance with the requirements of finished product standards are shown. A promising way to solve this problem in foundry is to use a probabilistic approach and the Monte Carlo method. The article presents formulas for calculating the strength and hardness of cast iron castings with lamellar graphite depending on its carbon equivalent and degree of eutecticity. The peculiarity of the proposed formulas, which gives them enhanced reliability and validity, is that the carbon equivalent and the degree of eutecticity of cast iron in them are determined by the Monte Carlo method using a probabilistic approach with regard to the consideration of the ranges of variation of the content of chemical elements in the cast iron composition regulated in the standard for foundry products. It is noted that the widespread use of thermal derivative express analysis of liquid cast iron in industry is constrained by the lack of a database of reference cooling curves with certain property indicators (chemical composition, microstructure, mechanical and other properties) of cast irons at foundries. Keywords: foundry, cast iron, chemical composition, properties, control, regulation, methodology.
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Svidró, Péter, Attila Diószegi, and Pär G. Jönsson. "Extended Method of Volume Change Measurements during Solidification of Lamellar Graphite Iron." Materials Science Forum 925 (June 2018): 163–70. http://dx.doi.org/10.4028/www.scientific.net/msf.925.163.
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Lamellar graphite iron (LGI) is an important technical alloy used to produce cast components for the automotive and the marine industry. The performance of the component is defined by the solidification sequence. Therefore, a lot of research work has been done in the field of solidification. The present work introduces a new measurement approach that combines advanced dilatation measurements with thermal analysis to investigate the solidification of LGI. The method involves a thermally balanced spherical sample. The temperature values are measured in the geometrical center and on the surface of the sample. The released heat of solidification is calculated by using the Fourier Thermal Analysis (FTA) method. The displacement values are measured on the surface of the sample. The volume change is calculated from the displacement data. The dilatation results clearly shows the advantage of the multidirectional measurement.
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Gabets, Denis, Andrey Markov, Mikhail Guryev, Evgeny Pismenny, and Alina Nasyrova. "The effect of complex modification on the structure and properties of gray cast iron for tribotechnical application." Metal Working and Material Science 24, no. 4 (2022): 165–80. http://dx.doi.org/10.17212/1994-6309-2022-24.4-165-180.
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Introduction. An approach based on the complex modification of cast irons makes it possible to improve its mechanical properties by changing the structure of the metal matrix, as well as the shape of graphite and its distribution. The aim of this work is to study the influence of alloying elements on the structure and mechanical properties of gray cast irons obtained for operation under friction wear conditions. Research methods. The paper describes the process of obtaining complex modified gray cast irons. Fractographic investigation of dynamically destroyed samples is carried out. Structure’s features of SCh35, ChMN-35M and SChKM-45 gray cast irons are studied. Tribological testing under sliding friction conditions is carried out. Results and its discussion. It is established that the complex modification of SCh35 gray cast iron with molybdenum, nickel and vanadium makes it possible to increase its hardness to 295 HB and tensile strength to 470-505 MPa. Alloying with nickel (0.4-0.7 wt.%), molybdenum (0.4-0.7 wt.%) and vanadium (0.2-0.4 wt.%) leads to a decrease in the interlamellar distance of perlite by 2 times, as well as to the metal matrix grain refining. The length of graphite lamellas of modified cast irons is reduced by 3-5 times. An additional effect on the tensile strength of cast iron is due to the alloying of ferrite with molybdenum and vanadium, which is fallen out along the boundaries of graphite inclusions. Alloying of ferrite with molybdenum and vanadium increases the level of its microhardness by 1.4 times in comparison with the α-phase of SCh35 serial cast iron. The results of tribotechnical tests of the designed materials are presented. Conclusions. It is established that the wear of specimens made of SChKM-45 cast iron is approximately 20-30% lower compared to cast iron SCh35 cast iron and 10-15% lower compared to ChMN-35M cast iron. Fractographic studies show that complex alloying with molybdenum, vanadium and nickel, contributing to the refining of pearlite colonies, leads to a decrease of the size of the cleavage facets.
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Slynko, G., and V. Slynko. "Structure forming and managing of properties of phosphorous cast irons for parts of internal combustion engine." Innovative Materials and Technologies in Metallurgy and Mechanical Engineering, no. 2 (March 18, 2021): 6–12. http://dx.doi.org/10.15588/1607-6885-2020-2-1.
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Purpose. Improving the mechanical and operational properties of details of internal combustion engines by managing the structure formation of phosphorous cast irons.
 Research methods. Graphitized and bleached phosphorous cast irons with lamellar and globular graphite of laboratory and industrial melts, melted in electric induction furnaces with alloying modification and fractional casting into dry sand molds were investigated. Chemical composition, microstructure, physical and mechanical properties were determined using standard methods. Non-destructive quality control of engine parts, statistical analysis of experimental data and deterministic factor analysis of the influence of structural components on the properties of the cast irons were carried out according to the methods developed with the participation of the authors. Bench and road motor tests of optimal composition cast irons details were carried out in engines according to standard and factory methods in accordance with state standards.
 Obtained results. The general laws and principles of the formation of the microstructure of cast irons with lamellar and nodular graphite are determined depending on the degree of their alloying with phosphorus and the influence of the scale factor. It has been established that phosphide eutectic in an amount of up to 5.8 % is a strengthening structural component and increases strength, hardness, wear resistance, heat resistance, and machin-ability of phosphorous cast irons with blade tools. The negative effect of phosphide eutectic on plastic properties and cyclic fracture toughness is less significant than the effect of increasing amounts of ferrite, its grain size and graphite. Optimal chemical compositions and microstructures of phosphorous cast irons for internal combustion engines details are recommended.
 Scientific novelty. For the first time, a comprehensive system for managing the properties of phosphorous cast irons has been developed, including the analytical determination of the required characteristics of structural components and the technology for their production.
 Practical value. Methods and technologies for melting, alloying, modifying, heat treatment and surface hardening of phosphorous cast irons have been developed. They make it possible to provide the required level of mechanical and operational properties of internal combustion engines details.
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Hiratsuka, S., and D. M. Stefanescu. "Measurement of Permeability on the Mushy Zone of Lamellar Graphite Cast Iron." Advanced Materials Research 4-5 (October 1997): 327–34. http://dx.doi.org/10.4028/www.scientific.net/amr.4-5.327.
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Mampaey, Frans. "Quantification of the solidification morphology of lamellar and spheroidal graphite cast iron." International Journal of Cast Metals Research 11, no. 5 (1999): 307–12. http://dx.doi.org/10.1080/13640461.1999.11819291.
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