Journal articles: 'Sinter (Metallurgy) Powder metallurgy'

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Donaldson, I. W. "High Thermal Conductivity Aluminum Powder Metallurgy Materials." Materials Science Forum 783-786 (May 2014): 120–25. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.120.

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High thermal conductivity aluminum has special advantages for electronic packaging and thermal management applications because of the combination of excellent thermal conductivity and relatively low density. Recent development of new press-and-sinter aluminum materials with low levels of alloying that sinters to a high density yielding a high thermal conductivity approaching the theoretical value for pure aluminum. The sintered materials possess thermal conductivity (TC) exceeding 200 w/m-oK (typically 215 – 230 w/m-oK), which makes it unique, since cast and wrought aluminum materials typically fall below 175 w/m-oK. This allows the benefits of powdered metal for low cost manufacturing at high volumes of parts to be realized. This unique combination of low cost and high TC makes these materials an attractive alternative to higher TC materials such as copper. In addition, a metal matrix composites (MMCs) press and sinter approach to tailoring the coefficient of thermal expansion (CTE) can also be used.

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Hwang, K. S., M. W. Wu, and Chia Cheng Tsai. "High Strength Sinter-Hardening Powder Metallurgy Alloys." Advanced Materials Research 51 (June 2008): 3–9. http://dx.doi.org/10.4028/www.scientific.net/amr.51.3.

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High strength and high hardness can be readily attained after sintering when sinter-hardening grade powder metallurgy alloys are used. However, fast cooling rates greater than 60°C/min are usually required. This increases the cost of the sintering equipment and maintenance. To lower the required minimum cooling rate, the homogeneity of the alloying elements in the matrix and the hardenability of the material must be improved. Among the various popular alloying elements, nickel and carbon are the two most non-uniformly distributed elements due to their repelling effect. It is found that to improve their homogenization, the addition of Cr and Mo can alleviate the repelling effect between Ni and C. As a result, weak Ni-rich/C-lean ferrite and austenite are eliminated and replaced by hard bainite and martensite. A tensile strength of 1323 MPa and a hardness of 39 HRC are attained in sinter-hardened Fe-3Cr-0.5Mo-4Ni-0.5C compacts without any quenching treatment.

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Zhang, Han Liang, Hui Ping Tang, Zeng Feng Li, and Chang Shu Xiang. "Preparation of Tin - Titanium Alloy in Powder Metallurgy Method." Advanced Materials Research 490-495 (March 2012): 3376–81. http://dx.doi.org/10.4028/www.scientific.net/amr.490-495.3376.

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Tin - Titanium alloy has been prepared by powder metallurgy method. By the way of preparing pre-alloyed metal and fully fine to ultra fine powder, optimizing sintering techniques, the Problem of enrichment of titanium from the alloy has been solved, the Tin - Titanium alloy with its homogeneous distribution elements has been made. Then the Tin-titanium strap has been processed successfully. In this paper, the key process to make Ti -Titanium alloy by Powder Metallurgy Method is introduced. The factors which affect the uniform components of the alloy have been mainly analyzed, such as ultra fine powder of pre-alloyed metal, diffusing sinter at lower temperature .etc. The results indicate that powder metallurgy with ultra fine powder additive and diffusing sinter at lower temperature is the efficient method to solve titanium element in the alloy segregate.

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Wang, Yan Jun, and Zuo Min Liu. "Micro-Pore Structure and Mechanical Properties of High Temperature Self-Lubricating Biomimetic TiC/FeCrWMoV Cermets." Materials Science Forum 546-549 (May 2007): 2273–78. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.2273.

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A new cermet sinter with sweat-gland micro-pore structure has been developed by powder metallurgy technology in vacuum. The effects of the pore-forming materials on micro-pore structure and Y2O3 additions as well mechanical properties of TiC/FeCrWMoV cermets were investigated. Some typical sweat-gland micro-pores were formed while compound additives TiH2 and CaCO3 adding into the sinter matrix. The porosity of the cermet sinters changes from 20% to 28% with the compound additives from 6% to 8%, and the micro-pores of sinters exist a regularized and interpenetrated network structure just like human’s sweat-gland one and obeying to Rayleigh Distribution. As such the sinters could be easily infiltrated with high-temperature solid lubricant. For improving the property of the ceramet sinter, the elements Y2O3 of 0.6～0.8% (vol. fraction ) was also added into the sinter matrix and its effect on the sinter has been also discussed .

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Jiang, Z., C. Lucien Falticeanu, and I. T. H. Chang. "Warm Compression of Al Alloy PM Blends." Materials Science Forum 534-536 (January 2007): 333–36. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.333.

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With the onging trend of reducing the weight of automotive parts, there is also an increasing trend in the use of light alloys. Recently, aluminum powder metallurgy has been the subject of great attention due to the combination of the lightweight characteristics of aluminium and the efficient material utilisation of the powder metallurgical process, which offer attractive benefits to potential end-users. Conventional press and sinter route of non-ferrous P/M products are based compaction at room temperature prior to the sintering cycle. However, warm compaction process has successfully provided increased density in ferrous powder metallurgy parts, which contributes to better mechanical properties and consequently overall performance of those parts. This study is aimed at exploring the use of warm compaction process to aluminium powder metallurgy. This paper presents a detailed study of the effect of warm compression and sintering conditions on the resultant microstructures and mechanical properties of Al-Cu-Mg-Si PM blend.

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Petroni, S. L. G., E. T. Galvani, Carlos Alberto Alves Cairo, C. C. Girotto, and V. A. R. Henriques. "Evaluation of Press-and-Sinter Processing Parameters in Titanium Hydride Powder Metallurgy." Key Engineering Materials 704 (August 2016): 94–103. http://dx.doi.org/10.4028/www.scientific.net/kem.704.94.

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The use of hydrogenated titanium powders combined with traditional PM techniques may lead to a significant reduction in the manufacturing costs of titanium components. In this work, the advantages and limitations of the use of TiH2 powder consolidated through the conventional press-and-sinter method were investigated. Processing parameters related to the compaction and sintering were studied for a TiH2 powder in the particle sizes <355 μm, <150 μm and <45 μm. Optimized compaction conditions were achieved by using admixed lubricant and compaction pressure of 800 MPa. The mechanisms involved in the compaction of powders were detailed through the fit of compressibility data to a theoretical model originally developed for titanium powders. Densification of samples was favored by the reduction in particle size and increase in sintering temperature up to 1300 °C. The positive effects of hydrogen release during dehydrogenation were verified through the results of sintered densities and the reduction of oxygen levels. Limitations were observed mainly regarding the flowability of powders and the difficulty to achieve full densification.

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Kandavel, TK, R. Sravanesh, and P. Karthikeyan. "Optimization of working parameters on wear behaviour of the sinter-forged plain carbon steel." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 231, no. 8 (October 24, 2015): 1379–88. http://dx.doi.org/10.1177/0954405415592200.

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Powder metallurgy plain carbon steel (Fe–0.5% C) replaces gradually the conventional C45 steel in all industrial sectors due to its comparable strength and better metallurgical properties. This research investigates the influence of density/porosity of powder metallurgy plain carbon steel on wear characteristics and optimizes the wear working parameters to establish minimum wear loss and coefficient of friction during wear using Taguchi-grey relational optimization analysis. The sintered steel preforms were subjected to uni-axial compressive load (cold upset) to obtain various percentage theoretical densities. The wear test specimens made out of various densities of the sinter-forged plain carbon steel were used to conduct wear tests as per the test plan generated by the Design Expert software. The optical and scanning electron microscope images taken from the worn test specimens were used for the investigations of wear mechanisms of the alloy steel. It is observed from the wear test results that the porosity in the powder metallurgy plain carbon steel has a vital role in wear properties of the steel. It has also been found that the optimized working parameters such as speed and load are found as same irrespective of the densities of the plain carbon steel.

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Ahamed, Riaz, Reza Ghomashchi, Zonghan Xie, and Lei Chen. "Powder Metallurgy Synthesis of Heusler Alloys: Effects of Process Parameters." Materials 12, no. 10 (May 15, 2019): 1596. http://dx.doi.org/10.3390/ma12101596.

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Ni45Co5Mn40Sn10 Heusler alloy was fabricated with elemental powders, using a powder processing route of press and sinter, in place of vacuum induction melting or arc melting route. The effects of process parameters, such as compaction load, sintering time, and temperature, on the transformation characteristics and microstructures of the alloy were investigated. While the effect of compaction pressure was not significant, those of sintering time and temperature are important in causing or annulling martensitic transformation, which is characteristic of Heusler alloys. The processing condition of 1050 °C/24 h was identified to be favorable in producing ferromagnetic Heusler alloy. Longer durations of sintering resulted in an increased γ-phase fraction, which acts as an impediment to the structural transformation.

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Bao, Chong Xi, Zhou Qiang Shen, and Zheng Ping Shu. "The Application of P/M Advanced Techniques to Sintered Gears." Materials Science Forum 534-536 (January 2007): 321–24. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.321.

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The processes of P/M affect the properties of sintered gears. The different techniques of P/M lead to the different properties of sintered gears. This paper summarizes new progress in powder metallurgy for sintered gears. These progresses include warm compaction, high velocity compaction, sinter hardening, high temperature sintering, infiltration, CNC powder press and surface densification etc.

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Danninger, Herbert. "Perspectives of Powder Metallurgy in the 2020s." Advanced Engineering Forum 34 (October 2019): 18–27. http://dx.doi.org/10.4028/www.scientific.net/aef.34.18.

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In the automotive industry there is a clear trend towards alternative drivetrain systems, away from the classical internal combustion – gasoline or diesel - engines. This poses a challenge to the traditional markets of powder metallurgy, the ferrous precision parts for automotive engines and transmissions which form the major tonnage of today’s powder metallurgy [1, 2], but also the hardmetal tools for machining automotive components from stock material or for finishing [3]. To counter these trends, powder metallurgy can rely on its high flexibility regarding materials, geometries, processing and properties and finally applications, which enables PM to adapt itself to changing requirements in a changing industrial environment [4]. In the present article, examples are given both for PM precision parts and hardmetals but also functional materials such as soft magnetic composites. It is shown that the potential of ferrous PM parts regarding mechanical performance is still higher than currently used, high and graded density being attractive ways [5]. Also the use of advanced alloying systems offers economical and technical advantages and should enable PM to enter non-automotive markets for precision parts. In the hardmetal branch, non-automotive applications, e.g. in construction and mining, should be considered while from the material viewpoint replacing tungsten and in particular Co as binder metal are intensely studied. PM functional materials such as Fe-Ni, Fe-Co and in particular soft magnetic composites will find markets in electrical drive systems [6], enabling new designs for electric motors. On the other end of the spectrum, superhard rare earth magnets are regularly produced by the powder route. Finally, the multitude of additive manufacturing techniques offers chances for powder metallurgy since most of these processes start from metal powders [7]. In addition to the well known laser and electron beam based “direct” AM systems, also indirect, binder-based, variants are attractive, avoiding many problems encountered with the direct systems and enabling transfer of knowhow accumulated in metal injection moulding. In general, future will show how many other technologies and products has to offer in addition to the classical press-and-sinter routes which however will remain for their specific product groups. when designing your figures and tables, etc

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MacAskill, I. A., I. W. Donaldson, and D. P. Bishop. "On development of press and sinter Al–Ni–Mg powder metallurgy alloys." Powder Metallurgy 49, no. 4 (December 2006): 314–22. http://dx.doi.org/10.1179/174329006x128377.

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Rhomar, Zeflianto, Ardian Putra, and Astuti Astuti. "Sintesis Aluminium Matrix Composites (AMC) Berpenguat Sinter Silika dengan Metode Powder Metallurgy." Jurnal Fisika Unand 6, no. 2 (April 4, 2017): 101–6. http://dx.doi.org/10.25077/jfu.6.2.101-106.2017.

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Aluminium Matrix Composites (AMC) telah disintesis dari aluminium serbuk sebagai matriks dan sinter silika (berbentuk serbuk) sebagai pengisi yang berasal dari mata air panas Sentral, Solok Selatan, Sumatera Barat dengan menggunakan metode powder metallurgy. Sintesis dilakukan dengan cara mencampur aluminium dengan sinter silika, dilakukan 4 variasi massa, yaitu 80 g : 5 g ; 80 g 10 g ; 80 g : 15 g dan 80 g : 20 g dengan menggunakan media pelarut, yaitu metil alkohol. Campuran diaduk selama 210 menit dengan menggunakan hot plate magnetic stirrer, kemudian endapan yang tersisa dikeringkan dengan oven selama 60 menit dengan temperatur 100oC. Endapan yang telah dikeringkan kemudian digerus sebanyak 0,5 g untuk masing-masing sampel dikompaksi sehingga berbentuk pelet. Pelet disintering dengan furnace selama 180 menit dengan temperatur 600oC. Pelet yang telah disintering diukur massa kering, diameter, tinggi dan massa basahnya setelah dicelupkan ke dalam air selama 12 menit kemudian dapat dihitung nilai densitas dan porositas setelah sintering dan porositasnya. Dari hasil perhitungan, densitas komposit setelah sintering cenderung memiliki nilai yang lebih kecil dibandingkan densitas komposit sebelum sintering. Berdasarkan perhitungan dan pengujian didapatkan persentase porositas dan kuat tekan, yaitu 40,72% dan 0,078 MPa untuk sampel 1, 39,12% dan 0,098 MPa untuk sampel 2, 39,51% dan 0,088 MPa untuk sampel 3 dan 44,45% dan 0,069 MPa untuk sampel 4. Berdasarkan hubungan kuat tekan dan porositas didapatkan hubungan σ = 0,8721e-5,757P dimana 0,8721 MPa menyatakan kuat tekan komposit tanpa pori. Kata kunci: AMC, densitas, pelet, porositas, powder metallurgy, sintering

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Peter, William H., Wei Chen, Yukinori Yamamoto, R. Dehoff, T. Muth, Stephen D. Nunn, Jim O. Kiggans, et al. "Current Status of Ti PM: Progress, Opportunities and Challenges." Key Engineering Materials 520 (August 2012): 1–7. http://dx.doi.org/10.4028/www.scientific.net/kem.520.1.

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Utilization of titanium components made by powder metallurgy methods has had limited acceptance largely due to the high cost of titanium (Ti) powder. There has been renewed interest in lower cost economical powders and several Ti reduction methods that produce a particulate product show promise. This talk summarizes work done at Oak Ridge National Laboratory to consolidate these economical powders into mill products. Press and sinter consolidation, hot isostatic pressing (HIP) and direct roll consolidation to make sheet have been explored. The characteristics of the consolidated products will be described as a function of the consolidation parameters.

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Straffelini, G., M. Benedetti, and V. Fontanari. "Damage evolution in sinter-hardening powder-metallurgy steels during tensile and fatigue loading." Materials & Design 61 (September 2014): 101–8. http://dx.doi.org/10.1016/j.matdes.2014.04.027.

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Robert-Perron, E., C. Blais, and S. Pelletier. "Tensile properties of sinter hardened powder metallurgy components machined in their green state." Powder Metallurgy 52, no. 1 (March 2009): 80–83. http://dx.doi.org/10.1179/174329007x205055.

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Moghaddam, Sheikhi, H. Farhangi, M. Ghambari, and N. Solimanjad. "Effect of sinter hardening on mechanical properties of Astaloy CrM powder metallurgy steel." Micro & Nano Letters 7, no. 9 (September 1, 2012): 955–58. http://dx.doi.org/10.1049/mnl.2012.0641.

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Kulkarni, Vinay R., Jagannath Nayak, and Vikram V. Dabhade. "Effect of chromium addition on properties of sinter-forged Fe–Cu–C alloy steel." International Journal of Modern Physics B 32, no. 19 (July 18, 2018): 1840040. http://dx.doi.org/10.1142/s0217979218400404.

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The present work deals with sinter-forged powder metallurgical (P/M) steels alloyed with chromium by addition of ferrochrome powder, which allows a close control over the chromium contents of alloy steels. Chromium contents can be varied by adjusting appropriately weighed ferrochrome powder in the P/M mixtures. Fe–Cu (2%) and C (0.7%) is the base composition for this P/M alloy steel. Study with the addition of 0.5% and 3% chromium by weight in the form of ferrochrome powder is carried out. The P/M alloy steel of base composition with no chromium content is also prepared for comparative study. The paper deals with these three alloy steels formed by the sinter-forging technique of powder metallurgy. The results of hardness and wear in hardened and tempered condition are reported in the present work.

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Gobber, Federico Simone, Jana Bidulská, Alessandro Fais, Róbert Bidulský, and Marco Actis Grande. "Innovative Densification Process of a Fe-Cr-C Powder Metallurgy Steel." Metals 11, no. 4 (April 19, 2021): 665. http://dx.doi.org/10.3390/met11040665.

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In this study, the efficacy of an innovative ultra-fast sintering technique called electro-sinter-forging (ESF) was evaluated in the densification of Fe-Cr-C steel. Although ESF proved to be effective in densifying several different metallic materials and composites, it has not yet been applied to powder metallurgy Fe-Cr-C steels. Pre-alloyed Astaloy CrM powders have been ad-mixed with either graphite or graphene and then processed by ESF. By properly tuning the process parameters, final densities higher than 99% were obtained. Mechanical properties such as hardness and transverse rupture strength (TRS) were tested on samples produced by employing different process parameters and then submitted to different post-treatments (machining, heat treatment). A final transverse rupture strength up to 1340 ± 147 MPa was achieved after heat treatment, corresponding to a hardness of 852 ± 41 HV. The experimental characterization highlighted that porosity is the main factor affecting the samples’ mechanical resistance, correlating linearly with the transverse rupture strength. Conversely, it is not possible to establish a similar interdependency between hardness and mechanical resistance, since porosity has a higher effect on the final properties.

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Geroldinger, Stefan, Raquel de Oro Calderon, Christian Gierl-Mayer, and Herbert Danninger. "Applying the Masteralloy Concept for Manufacturing of Sinter Hardening PM Steel Grades." Advanced Engineering Forum 42 (September 7, 2021): 17–23. http://dx.doi.org/10.4028/www.scientific.net/aef.42.17.

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Sinter hardening is a powder metallurgy processing route that combines the sintering and the heat treating processes in one step by gas quenching the components immediately after they have left the high temperature zone of the furnace. It is both economically attractive and ecologically beneficial since it renders deoiling processes unnecessary. The slower cooling rates associated with gas compared to oil quenching however requires special alloy concepts different to those known from wrought steels. In the present study it is shown that by admixing atomized masteralloy powders consisting of suitable combinations of Mn, Cr, Si, Fe and C to base iron or pre-alloyed steel powders, sinter hardening PM steel grades can be produced that transform to martensitic microstructure at cooling rates of 2-3 K/s as typical for industrial sinter hardening. This is confirmed by CCT diagrams and hardness measurements. However, metallographic investigations are also necessary because in sintered steels, the cores of the largest base powder particles are alloyed very slowly during sintering and therefore tend to result in soft spots in the sinter hardened microstructure which are mostly not discernible in the CCT diagrams. Here, even slight pre-alloying of the base powder with Mo and/or Cr is helpful, both increasing the hardenability of the steels compared to base plain iron and avoiding soft spots in the microstructure.

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Blaine, Deborah C., Hendrik L. Bosman, and Heleon H. Laubscher. "Process Models for Press-and-Sinter Titanium." Advanced Materials Research 1019 (October 2014): 231–40. http://dx.doi.org/10.4028/www.scientific.net/amr.1019.231.

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Two commercially pure (CP) titanium powders, with mean particle sizes of 78 and 32 μm, respectively, were used to manufacture titanium samples via the press-and-sinter powder metallurgy process. Compaction pressures ranging from 300 to 500 MPa were used to compact the powders into cylindrical and rectangular forms. The green samples were sintered for 2 hours under high vacuum, 10-6 mbar, at 1100, 1200 and 1300 °C, respectively. Green density and green strength data were collected from the compacted samples, and sintered density, sintered strength and microstructure images were collected from the sintered samples. These data were used to characterise process models for the compressibility of the powders, and for the sinter densification, using the Master Sintering Curve (MSC) model. The results show that particle size influences the processing at both the compaction and sintering step. In modelling these two processes, separate MSC models must be characterised and each used individually to predict each one’s final sintered density. It is shown that if the densification parameter is used to characterise the sintering model, a unified Master Densification Curve (MDC) is found. The modified MDC model can be used to predict the final sintered density regardless of the initial green density or mean particle size of the powder.

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Nicolicescu, Claudiu, Victor Horia Nicoară, and Costel Silviu Bălulescu. "Synthesis of Cu/Cr and Cu/Cr/W Materials by Powder Metallurgy Techniques." Applied Mechanics and Materials 880 (March 2018): 241–47. http://dx.doi.org/10.4028/www.scientific.net/amm.880.241.

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Alloys based on Cu/Cr and Cu/Cr/W attract the attention due to their presence in different applications that require higher electrical properties which are combined with good mechanical properties. In order to synthesis the material based on Cu/Cr and Cu/Cr/W, mechanical alloying technique was used. Four mixtures, X1 (99%CuCr), X2 (97%CuCr), X3 (94%Cu1%CrW), X4 (92%Cu3%CrW – weight percent), were prepared using a vario planetary ball mill Pulverisette 4 made by Fritsch. The mixtures obtained after 10 hours were analyzed by scanning electron microscopy (SEM). It was found that the presence of chromium and tungsten influence the morphology and the particles tend to be flat. Sinter ability and microhardness are influenced by the chemical composition of the samples.

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Harding, Matthew, Ian Donaldson, Rich Hexemer Junior, and Donald Bishop. "Effects of Post-Sinter Processing on an Al–Zn–Mg–Cu Powder Metallurgy Alloy." Metals 7, no. 9 (September 13, 2017): 370. http://dx.doi.org/10.3390/met7090370.

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Martin, F., C. García, Y. Blanco, and G. Herranz. "Influence of sinter-cooling rate on intergranular corrosion of powder metallurgy superaustenitic stainless steel." Corrosion Engineering, Science and Technology 49, no. 7 (March 26, 2014): 614–23. http://dx.doi.org/10.1179/1743278214y.0000000165.

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Qiu, Hui, Yong Gang Zhu, and Li Zhang. "Thermal Stress Analysis of Powder Metallurgy Sintering Process Based on ANSYS." Key Engineering Materials 667 (October 2015): 244–49. http://dx.doi.org/10.4028/www.scientific.net/kem.667.244.

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Powder metallurgy is a technology process that the powder is pressed and sintered to get the metal and composite products. The sintering temperature is one of the main technology parameters of pressing sintering. In significant measure, the sintering temperature determines the organization and geometry size of the material, which directly affects the performance of the material. This paper takes magnesium powder metallurgy sintering material as the research object, studying the transient thermal analysis with the ANSYS finite element software, systematic researching the sinter temperature field and thermal stress field of sintered body in the sintering process, and observing in the corresponding distribution of stress field and deformation under different sintering temperature distribution graph. Temperature field and thermal stress field are the main factors affecting the quality of the sintered body in sintering process. Uneven temperature distribution will cause larger thermal stress. When the thermal stress exceeds a certain limit, the sample will be deformed. With the temperature increases, the sintering temperature difference increases, the stress distribution in the constantly changes. The stress and deformation is not entirely visible for sintered body, the deformation and cracking will be side by side in the sintering process. Therefore, theory of temperature field and thermal stress distribution are studied and discussed in certain sintering processing, the sintering process optimization can be designed to provide quantitative basis of the theoretical analysis.

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Garcia-Cabezon, C., F. Martin-Pedrosa, Y. Blanco-Val, and M. L. Rodriguez-Mendez. "Corrosion Properties of a Low-Nickel Austenitic Porous Stainless Steel in Simulated Body Fluids." Corrosion 74, no. 6 (January 29, 2018): 683–93. http://dx.doi.org/10.5006/2720.

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Nickel can cause severe allergic reactions. Therefore, efforts are made to reduce the content of nickel in austenitic stainless steels (SS). Powder metallurgy (PM) techniques can produce this steel in a highly affordable way. A novel low-nickel high-nitrogen austenitic powder metallurgy PM stainless steel is investigated in terms of corrosion behavior. Nitrogen, because of its gammagenic effect, is the applied sintering atmosphere. Two sintering processes are applied by controlling the sinter-cooling rate (furnace- and water-cooling). This material shows an austenitic microstructure free of precipitates only after the water-cooling process. The electrochemical behavior in two simulated body fluids—phosphate buffered saline (PBS) solution and Ringer solution—are studied. Corrosion behavior is evaluated by means of anodic polarization measurements and cyclic polarization curves. In addition, Electrochemical Impedance Spectroscopy is used to evaluate the corrosion resistance of this steel in PBS at open circuit potential and at 100 mV above corrosion potential. The water-cooling process promotes better corrosion behavior in simulated body fluids for high nitrogen and low nickel than a conventional (high nickel) austenitic PM SS 316LN type.

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Geroldinger, S., R. de Oro Calderon, C. Gierl-Mayer, and H. Danninger. "Sinter Hardening PM Steels Prepared through Hybrid Alloying." HTM Journal of Heat Treatment and Materials 76, no. 2 (April 1, 2021): 105–19. http://dx.doi.org/10.1515/htm-2020-0007.

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Abstract In powder metallurgy (PM), there are several ways of introducing alloying elements into a PM material in order to adjust a certain alloying element content. Each alloying route has its advantages and disadvantages. Master alloys (MA), powders with a high content of typically several alloying elements, can be added in small amounts to a base powder, especially to introduce oxygen sensitive elements such as Cr, Mn, and Si. In addition, the master alloy can be designed in such a way that a liquid phase is formed intermediately during the sintering process to improve the distribution of alloying elements in the material and to accelerate homogenization. In this study, such master alloys were combined with pre-alloyed base powders to form hybrid alloyed mixtures with the aim of improving the material‘s sinter hardenability. The hybrid alloys were compared with mixtures of master alloy and plain Fe as reference material. The sinter hardenability of all materials was determined by generating CCT diagrams recorded with 13 different cooling rates. These were verified by metallographic cross-sections of specimens treated at common cooling rates of 3 and 1.5 K/s and subsequent hardness measurements of the microhardness (HV 0.1) of the microstructural constituents and the apparent hardness (HV 30). ◼

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Goh, F. C. W., M. A. Hodgson, and P. Cao. "A New Multifunctional β Ti Alloy Produced via Powder Metallurgy for Biomedical Applications." International Journal of Modern Physics: Conference Series 06 (January 2012): 688–93. http://dx.doi.org/10.1142/s2010194512003984.

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Recent studies have revealed remarkable properties in β- Ti alloys, including low elastic modulus, high strength and superelasticity. The unique properties and potentials in engineering and biomedical applications have invoked many physicists, material scientists and metallurgists to study its phenomenon. The requirements of these alloys in biomedical applications restrict the usage of toxic or allergic elements in the alloy design. Only a few alloying elements are suitable for developing non-toxic β titanium alloys such as Nb , Ta and Zr . In this study a press-and-sinter process was used to consolidate the elemental powder mixture of Ti - Nb - Ta - Zr . Solid state sintering studies were established to investigate the effect of various green densities, sintering temperatures (i.e. 1650 °C – 1700 °C) and sintering atmosphere (i.e. Argon and Vacuum). PM near net shape process of showed a pathway to obtained a near dense part at sintered density of ~97 % with compaction pressure of 707 MPa at 1700°C. Majority of the sintered Ti -23 Nb -0.7 Ta -2 Zr (at.%) alloy's structure is β- austenite (bcc).

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Mansourirad, Nima, Mohammad Ardestani, and Reza Afshar. "Synthesis and characterization of Ag-8 %wt Cr2O3 composites prepared by different densification processes." Science of Sintering 50, no. 3 (2018): 323–35. http://dx.doi.org/10.2298/sos1803323m.

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A novel Ag-8 %wt Cr2O3 composite prepared via powder metallurgy route. Silver and chromium oxides were used as starting powders. The powder mixtures were mechanically milled by a SPEX high energy mill for 5 h. Based on the thermogravimetric analysis (TGA) and X-Ray Diffraction (XRD) results, the milled powders were calcined in an argon atmosphere at 550?C. During calcination, the silver oxide decomposed into silver. The results showed that the Heckel equation was the preferred one for description the cold compressibility of the powders. The calcined powders were consolidated by Press-Sinter-Repress (PSR), Press-Sinter-Repress-Anneal (PSRA) and Spark Plasma Sintering (SPS) processes. The Field Emission Scanning Electron Microscope (FESEM) investigations showed a nearly dense microstructure of the sintered samples. However, the hardness of the pressed-sintered-repressed samples was 81 Vickers which was the highest among the processed specimen. Furthermore, the flexural strength of the PSR and SPS processed samples were 231 and 255 MPa, respectively which were too higher than that of the annealed specimens. The results confirmed the effect of microstructural parameters such as Cr2O3 particle size and processing route on the mechanical properties of the sintered composites.

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Shanmugasundaram, D., and R. Chandramouli. "Tensile and impact behaviour of sinter-forged Cr, Ni and Mo alloyed powder metallurgy steels." Materials & Design 30, no. 9 (October 2009): 3444–49. http://dx.doi.org/10.1016/j.matdes.2009.03.020.

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Chaurasia, Jitender, Muthuchamy Ayyapan, Paridh Patel, and Annamalai Raja. "Activated sintering of Tungsten heavy alloy." Science of Sintering 49, no. 4 (2017): 445–53. http://dx.doi.org/10.2298/sos1704445c.

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In the present work, characterization of sintering behavior of Tungsten heavy alloy has been done through powder metallurgy route using Spark plasma sintering (SPS). Fine powder of Tungsten (<30 ?m) was separately mixed with Ni, Co, Fe, Mo and Cu each with 1 weight%. Spark Plasma Sintering (SPS) technique (1200?C, 20 MPa pressure with 1 min holding time) was used to sinter the mixed powders. The maximum density was observed in W-Ni followed by Co, Fe, Cu, Mo and with least in pure tungsten sample. Optical microscopy as well SEM was done to determine the microstructure and grain coarsening. Due to the short heating time very less grain coarsening was observed. Vickers hardness test was conducted which resulted in maximum hardness in case if W-1Fe SPS sample.

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Metrima Firmansyah, Khoiril, Albertus Septyantoko, Mochammad Ghulam Isaq Khan, Paiman Jhony, Rosena Mardliah, and Widyastuti. "Effect of Fabrication Method by Powder Metallurgy on Frangibility Green Bullet Cu-10%Sn as Eco-Friendly Bullet." Advanced Materials Research 1112 (July 2015): 533–37. http://dx.doi.org/10.4028/www.scientific.net/amr.1112.533.

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The bullet is used for immobilize object. However it can harm the shooter because it can be ricochet. Thus it, we develop frangible bullet which can be broken when hit the hard target. Conventional bullets are made of lead base material which poison. Therefore frangible bullet does not use lead as base material, so it is classified as green bullet. Green bullet is made by powder metallurgy method. Powder metallurgy process are measuring copper and tin powder, dry mixing, and compacting 600 Mpa in pressure for 10 minutes in holding time, and sintering at 300, 500, 700°C for 0,5; 1; and 1,5 hours in holding time. Then, measure the sinter density and analyze the sample by XRD and SEM-EDX. Based on experiment, we found that the bullet Cu-10%wt which sintering 500 °C in temperature for 1 hour has the best frangibility. The highest theoretical density , compression strength, and hardness are 8.8 gr/cm3, 280.45 MPa, 60.67 HRF. The observer result by scanning electron microscope showed that the phase homogeneity at sintering temperature 500°C for 1 hour in holding times was better than the other variable. By observing phase formed, in XRD pattern show that identified new phase Cu10Sn3caused the material properties fragile.

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de Araújo Filho, Oscar Olimpio, Cezar Henrique Gonzalez, Severino Leopoldino Urtiga Filho, C. A. N. Oliveira, Noelle D’emery Gomes Silva, and F. Ambrozio Filho. "Secondary Hardening of an AISI M3:2 High Speed Steel Sinter 23 Hot Isostatic Pressed." Materials Science Forum 899 (July 2017): 361–65. http://dx.doi.org/10.4028/www.scientific.net/msf.899.361.

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The main aim of this work was to study the behavior of the secondary hardening of AISI M3:2 high speed steel named Sinter 23® produced by powder metallurgy process of hot isostatic pressing (HIP). The M3:2 high speed steel Sinter 23® was submitted to heat treatment of hardening with austenitizing temperatures of 1140 oC, 1160 oC, 1180 oC and 1200 oC and tempering at 540 oC, 560 oC and finally 580 oC. The effectiveness and response of the heat treatment was determined using hardness tests (Vickers and Rockwell C hardness) and had its property of secondary hardness evaluated. The results showed that the secondary hardening peak of Sinter 23® high speed steel (tempering temperature at which maximum hardness is attained) is at 540 °C for the lower austenitization temperatures of 1140 °C and 1160 °C, and it is at 560 °C for the higher austenitizing/quenching temperatures of 1180 °C and 1200°C.

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Abed Zaid, Hayder Muneam, Abdul Rahman N. Abed, and Hala Salman Hasan. "Effect of Alumina (Al2O3) Particles on The Mechanical Properties of Magnesium (Mg)." Al-Nahrain Journal for Engineering Sciences 22, no. 2 (July 21, 2019): 124–30. http://dx.doi.org/10.29194/njes.22020124.

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In the present study, magnesium-based composites reinforced with different volume fractions (3, 5, 10, and 15) vol.% of micro sized Al2O3 particulates were fabricated by powder metallurgy technique which involves mixed, compacted and sintered. Powders were mixed by ball milling (without balls) for 6 hours at rotation speed 60 rpm. Then powder was compacted at 550 MPa and sintered at 530˚C for 2 hours. Microstructures of sintered composites have been investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) energy dispersive. SEM image of sinter samples exhibit good bonding between the magnesium matrix and the alumina. The microhardness and wear resistance of micro composites has been improved significantly compared to that of pure magnesium. Highest value of microhardness is 97 HV at the volume fraction of 10 vol.% Al2O3.

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Choy, Man Tik, and Chak Yin Tang. "Effect of Porosity on Compressive Yield Strength of Microwave Sintered Titanium Components." Key Engineering Materials 626 (August 2014): 97–102. http://dx.doi.org/10.4028/www.scientific.net/kem.626.97.

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Titanium is widely used in biomedical implants because of its excellent mechanical properties, good biocompatibility and high resistance to corrosion. However, the fabrication of titanium components often involves high cost due to the long processing time and difficulty in metalworking. Powder metallurgy is a near-net-shape processing method which has the advantage of high production rate with low unit cost. In this study, a technique comprising microwave sintering with powder metallurgy has been developed to fabricate titanium components. Commercially pure titanium powdered compacts, prepared by three initial particle size groups of 10±2 μm, 30±2 μm, and 50±2 μm, were sintered in a 1.4 kW, 2.45 GHz microwave multi-mode furnace for 2 minutes using silicon carbide particles as the microwave susceptor to assist the heating. The room temperature deformation behavior of titanium components was investigated. Metallographic studies of the porosity and pore size were undertaken by optical microscopy. The results of this study indicate that irregular shaped pores were uniformly distributed within the sintered specimens. Furthermore, the pore size and porosity of the sintered specimens decrease with decreasing initial particle size. The compressive yield strength showed a linear relationship with the porosity, and was found to follow the Hall-Petch relationship with the initial particle size. This study demonstrated that it is feasible to microwave sinter titanium components having various compressive yield strengths by controlling the initial powder size of the titanium.

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Sońta, Grzegorz, Agata Dudek, Jacek Selejdak, and Robert Ulewicz. "Analysis of Structure of Elements for Automotive Industry." Applied Mechanics and Materials 712 (January 2015): 81–86. http://dx.doi.org/10.4028/www.scientific.net/amm.712.81.

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The paper presents the results of the structure and chemical composition of materials used to manufacture of gear wheel for the automotive industry. Analyzed gear wheel that is a part of one of the mechanical systems of an automotive vehicle was made of sinter Sint-D 32 in the technology of powder metallurgy and alloy structural steel for quenching and tempering 42CrMo4. The cause of the analysis was to research for an alternative material for sinter Sint-D 32 after identified low static strength according to the requirements applicable in the automotive industry. For the analysis were used standard test methods applicable in materials science. Based on microstructure and mechanical properties analysis performed according to requirements applicable in the automotive industry, the research found that steel 42CrMo4 is relevant material to be used in serial production for this particular gear wheel.

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Nogueira, Rejane A., Oscar O. Araújo Filho, Leonardo F. M. Souza, João Franklin Liberati, Lucio Salgado, and Francisco Ambrozio Filho. "Grain Size of Commercial High Speed Steel." Materials Science Forum 530-531 (November 2006): 16–21. http://dx.doi.org/10.4028/www.scientific.net/msf.530-531.16.

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The heat treatment of high speed steel tools consists of austenitizing, quenching and tempering. The size of austenite grains formed during the hardening treatment is an important factor in the final microstructure of the steel, and it also affects properties such as wear resistance and toughness. This paper presents the austenite grain size, matrix composition and hardness of commercial AISI M2, AISI T15, VWM3C and Sinter 23 high speed steels that were austenitized and quenched from five distinct temperatures. This study shows that increase in quenching temperature results in grain growth of steels such as AISI M2 and VWM3C, obtained by the conventional method (cast to ingot and worked). The P/M Sinter 23 high speed steel showed a slight grain growth (about 10%). This effect was not observed in AISI T15 obtained by the powder metallurgy process.

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Dunstan, Matt, Z. Zak Fang, Mark Koopman, and James Paramore. "Powder Metallurgy Ti-6Al-4V Alloy with Wrought-Like Microstructure and Mechanical Properties by Hydrogen Sintering." Key Engineering Materials 704 (August 2016): 3–14. http://dx.doi.org/10.4028/www.scientific.net/kem.704.3.

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Hydrogen sintering phase transformation (HSPT) is a low-cost, blended elemental, press and sinter powder metallurgy process. During HSPT, compacts of TiH2 powder are sintered in dynamically controlled partial pressures of hydrogen followed by a vacuum anneal (dehydrogenation). The use of hydrogen in the sintering atmosphere allows phase transformations in the Ti – H system to create an ultra-fine lamellar microstructure in the as-sintered state with mechanical properties that exceed ASTM standards. Additionally, the fine lamellar structure allows for secondary heat treatments to produce wrought-like microstructures. The removal of hydrogen in the dehydrogenation step is critical to prevent hydrogen embrittlement. The kinetics of dehydrogenation are discussed, in which a model for the concentration profile and an empirical equation for maximum hydrogen concentration as a function of time and size are developed.

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Falih, Doaa A., Fadhil A. Hashim, and Sabah Kh Hussein. "Investigation of Sinter Braze Ferrous Powder Metallurgy to Wrought Substrates by Ancorbraze 72 Filler Metal Alloy." IOP Conference Series: Materials Science and Engineering 518 (June 5, 2019): 032022. http://dx.doi.org/10.1088/1757-899x/518/3/032022.

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Chinnaiyan, S., S. Karuppazhagi, A. Veeramani, and S. Shanmugam. "Synthesis and forming behaviour of AA7075-TiC powder-metallurgy composites." Materiali in tehnologije 52, no. 6 (December 17, 2018): 809–12. http://dx.doi.org/10.17222/mit.2017.189.

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Fontanari, Vigilio, Alberto Molinari, Michelangelo Marini, Wolfgang Pahl, and Matteo Benedetti. "Tooth Root Bending Fatigue Strength of High-Density Sintered Small-Module Spur Gears: The Effect of Porosity and Microstructure." Metals 9, no. 5 (May 24, 2019): 599. http://dx.doi.org/10.3390/met9050599.

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The present paper is aimed at investigating the effect of porosity and microstructure on tooth root bending fatigue of small-module spur gears produced by powder metallurgy (P/M). Specifically, three steel variants differing in powder composition and alloying route were subjected either to case-hardening or sinter-hardening. The obtained results were interpreted in light of microstructural and fractographic inspections. On the basis of the Murakami a r e a method, it was found that fatigue strength is mainly dictated by the largest near-surface defect and by the hardness of the softest microstructural constituent. Owing to the very complicated shape of the critical pore, it was found that its maximum Feret diameter is the geometrical parameter that best captures the detrimental effect on fatigue.

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Llah, Noorazimah Ab, Shamsul Baharin Jamaludin, and Zuraidawani Che Daud. "The Effect of Sintering Temperature on the Sintered Mg/3wt.%Zn-Bioglass (45S5) Composites." Materials Science Forum 819 (June 2015): 325–30. http://dx.doi.org/10.4028/www.scientific.net/msf.819.325.

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Magnesium and bioglass are a good combination to create biocompatible and bioactive materials. Magnesium-bioglass composites can be manufactured by casting or sintering. This work was aimed to manufacture the composite Mg-3wt.%Zn filled with 5, 10, 15, 20, 25 and 30wt.% bioglass (45S5) by powder metallurgy. Two sintering temperatures of 450 °C and 550 °C were used to sinter the samples. The sintered samples were characterized using optical micrograph and X-Ray diffraction (XRD). Optical micrograph shows that increasing of bioglass content lead to smaller grain size. XRD analysis shows no new crystalline compound detected on XRD pattern for Mg-3wt%Zn sintered at 450 °C ad 550 °C.

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Hassan, S. F., and M. Gupta. "Development and Characterization of Ductile Mg∕Y2O3 Nanocomposites." Journal of Engineering Materials and Technology 129, no. 3 (January 11, 2007): 462–67. http://dx.doi.org/10.1115/1.2744418.

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Nano-Y2O3 particulates containing ductile magnesium nanocomposites were synthesized using blend-press-sinter powder metallurgy technique followed by hot extrusion. Microstructural characterization of the nanocomposite samples showed fairly uniform reinforcement distribution, good reinforcement-matrix interfacial integrity, significant grain refinement of magnesium matrix with increasing presence of reinforcement, and the presence of minimal porosity. Mechanical properties characterization revealed that the presence of nano-Y2O3 reinforcement leads to marginal increases in hardness, 0.2% yield strength and ultimate tensile strength, but a significant increase in ductility and work of fracture of magnesium. The fracture mode was changed from brittle for pure Mg to mix ductile and intergranular in the case of nanocomposites.

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Jiao, Ming Hua, Bing Chao Wan, Bai Wan Su, Shao Bo Ma, and Yan Guo Yin. "Study on Properties of Cupriferous and Boracic Iron Based Sintered Composites." Advanced Materials Research 756-759 (September 2013): 80–84. http://dx.doi.org/10.4028/www.scientific.net/amr.756-759.80.

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Pre-configured powders were mixed uniformly through bonding granulation method. The boracic iron based self-lubricating composites with copper of different mass were prepared by the powder metallurgy press-sinter process. The tribological properties under different conditions of load were investigated on HDM20 end-face tribometer. The composite structure, the wear mechanism which copper affect the friction and wear behaviors of boracic iron based composites were analyzed by using X-ray diffraction, EDS and metallographic microscope. The results show that elementary copper which forming alloy phase could strengthen the combination of each phase in composites, playing the role of binder, improve the tribological properties. The synergistic effect between the phases combination, hardness and strength of Cu-20w composite were observably, which lead to the excellent tribological properties synthetically.

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Yu, Jing Yuan, and Qiang Li. "Study on Effect of Sintering Temperature on Microstructure and Compressive Property of Porous NiTi Alloys." Advanced Materials Research 299-300 (July 2011): 480–83. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.480.

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Porous NiTi alloys were prepared by powder metallurgy method using NH4HCO3as space-holder. The effect of sintering temperature on pore characteristic, phase composition and compressive property of porous NiTi alloys was studied by XRD, SEM, EDS and a universal testing machine. The results show with the increase of sintering temperature the porosity of porous NiTi alloys first increases and then decreases, but the content of NiTi phase, compressive strength and modulous of sintered products continuously increase. When sintered at 980°C for 2h, the porous NiTi alloys have higher porosity of 53.6%, better compressive strength of 173.7MPa and elastic modulous of 4.2GPa. The phases of sinter products are mainly composed by TiNi, Ti2Ni, and TiNi3phases.

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Majchrowska, Magdalena, Konrad Lasek, Maja Nowak, Paweł Pałka, and Bartosz Sułkowski. "CHARACTERISTICS OF Al-Fe SINTERS MADE BY THE POWDER METALLURGY ROUTE." Metallurgy and Foundry Engineering 44, no. 4 (2018): 195. http://dx.doi.org/10.7494/mafe.2018.44.4.195.

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MAJEWSKI, Tomasz, Marcin SARZYŃSKI, Judyta SIENKIEWICZ, Jerzy SZAWŁOWSKI, Tomasz BABUL, and Sylwester JOŃCZYK. "Copper-Graphene Composite Materials: Manufacturing Technology and Properties." Problems of Mechatronics Armament Aviation Safety Engineering 10, no. 4 (December 30, 2019): 37–54. http://dx.doi.org/10.5604/01.3001.0013.6485.

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The article presents the results of preliminary research into the feasibility of copper-graphene composite application in the production of shaped charge liners in HEAT ammunition from graphene-coated copper grain powders by powder metallurgy techniques. Copper powder grains were coated with graphene with a machine and process developed at the Institute of Precision Mechanics in Warsaw (Poland). The characteristics of the applied powdered materials (including particle size distribution) were determined in this work. The paper discloses the result of graphene identification by Raman spectroscopy. The presence of graphene was confirmed in the processed copper powder. The paper discusses the preparation of copper powder by grinding (refinement) and reduction for consolidation. Powder mixtures of pure copper and graphene powder were applied at different component ratios. P/M compacts and sinters (agglomerates) for the test specimens were made from the proposed mixtures by die pressing and sintering in dissociated ammonia gas. Examples of microstructures and selected test results of material properties are shown for the produced sinters. The paper shows a selection of test results for the copper-graphene composites produced by PPS (Pulse Plasma Sintering) from 100% graphene-coated copper powder. The properties of the produced composite materials were determined, including their density, porosity, and a selection of mechanical properties identified by DSI (Depth Sensing Indentation). It was found that the copper-graphene composite met the primary design criteria applied to shaped charged liners for HEAT munitions. In “traditional” powder metallurgy processes, high-density products can be produced if the composite material features a low content of graphene-coated copper powder; PPS, however, makes the production viable with 100% graphene-coated copper powder.

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Tun, Khin Sandar, Akshay Padnuru Sripathy, Sravya Tekumalla, and Manoj Gupta. "Development of Novel Lightweight Metastable Metal–(Metal + Ceramic) Composites Using a New Powder Metallurgy Approach." Materials 13, no. 15 (July 23, 2020): 3283. http://dx.doi.org/10.3390/ma13153283.

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In the current study, metal–(metal + ceramic) composites composed of biocompatible elements, magnesium (Mg), zinc (Zn), calcium (Ca) and manganese (Mn) were synthesized using a sinter-less powder metallurgy method. The composite has a composition of Mg49Zn49Ca1Mn1 (wt.%) in which the compositional ratio between Mg and Zn was chosen to be near eutectic Mg-Zn composition. The synthesis method was designed to avoid/minimize intermetallic formation by using processing temperatures lower than the Mg-Zn binary eutectic temperature (~ 340 °C). The synthesis process involved extrusion of green compacts at two different temperatures, 150 °C and 200 °C, without sintering. Extrusion was performed directly on the green compacts as well as on the compacts soaked at temperatures of 150 °C and 200 °C, respectively. Microstructure and mechanical properties of the materials synthesized under various processing conditions were investigated. Effect of extrusion temperature as well as soaking temperature on the materials’ properties were also evaluated in details and different properties showed an optimum under different conditions. All the synthesized materials showed no evidence of intermetallic formation which was confirmed by SEM/EDS, XRD, and Differential Scanning Calorimetry (DSC) techniques. The study establishes development of unconventional metal–(metal + ceramic) eco-friendly composites and provides important insight into realizing certain properties without using sintering step thus to minimize the energy consumption of the process. The study also highlights the use of magnesium turnings (recyclability) to develop advanced materials.

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Gierl-Mayer, Christian, and Herbert Danninger. "Dilatometry Coupled with Mass Spectrometry as Instrument for Process Control in Sintering of Powder Metallurgy Steels." Materials Science Forum 835 (January 2016): 106–15. http://dx.doi.org/10.4028/www.scientific.net/msf.835.106.

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The production of ferrous powder metallurgical parts by the press-and-sinter route becomes more and more attractive. Today, parts are produced for loading requirements that until now only could be fulfilled by conventional produced steel components. The high mechanical properties that must be attained require the use of alloying elements so far not common in powder metallurgy because of their high affinity for oxygen. The sintering of chromium containing steels is a challenge for the whole production process, because the reduction of the surface oxides is critical for successful sintering.Dilatometry can be a useful instrument to control the sintering behaviour of the materials, especially the combination with mass spectrometry allows analysing the very complex sintering process and simultaneously monitoring the solid-gas reactions. This work shows that the sintering atmosphere plays a major role in the entire process. Degassing and deoxidation processes during sintering are demonstrated for different alloying systems (Fe, Fe-C, Fe-Mo-C, Fe-Cr-Mo-C). Dilatometry coupled with MS is shown to be a very good instrument for process control of the sintering process. The generated analytical data can be related to the mechanical properties of the sintered steels if the size of the specimen is large enough.

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Desbiens, Jean, Etienne Robert-Perron, Carl Blais, and François Chagnon. "Effect of green machining on the tensile properties and fatigue strength of powder metallurgy sinter-hardenable steel components." Materials Science and Engineering: A 546 (June 2012): 218–22. http://dx.doi.org/10.1016/j.msea.2012.03.054.

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Lakshmipathy, J., Subburaj Rajesh Kannan, K. Manisekar, and S. Vinoth Kumar. "Effect of Reinforcement and Tribological Behaviour of AA 7068 Hybrid Composites Manufactured through Powder Metallurgy Techniques." Applied Mechanics and Materials 867 (July 2017): 19–28. http://dx.doi.org/10.4028/www.scientific.net/amm.867.19.

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In this article, an attempt was made to study the mechanical behaviour of AA7068 - 6 vol. % of MoS2 - X vol. % of WC (X = 0, 5, 10 and 15) hybrid aluminium composites produced by blend–press–sinter methodology. Compacted Powders (700MPa) were sintered at different temperatures (450 0c, 500 0c and 550 0c ) in order to find the influence of sintering temperature on mechanical properties and tribological behavior of AA7068 hybrid composites.The sintered samples have been characterized by x-ray diffraction (XRD) method for identification of phases and also to investigate the phase changes. The change in density, hardness and porosity values of composites were reported. The composite with 15 vol. % of tungsten carbide and 6 vol. % of MoS2 showed the highest hardness and density at the sintering temperature range of 550 0c. Pin-on-disc type apparatus was used for determining the wear loss occurring at different conditions. The hybridization of the two reinforcements enhanced the wear resistance of the composites, especially under high applied load, sliding distance and sliding speeds. Due to this, the hybrid aluminium composites can be considered as an outstanding material where high strength and wear-resistant components are of major importance, predominantly in the aerospace and automotive engineering sectors. The morphology of the wear debris and the worn out surfaces were analyzed to understand the wear mechanisms.

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Journal articles on the topic 'Sinter (Metallurgy) Powder metallurgy'

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