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Journal articles on the topic 'Semi-finished bars'
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1
Zamozdra, Maxim Yu, Julija S. Karzina, and Anna Perminova. "Mechanical Properties of Bars Produced by Hot Extrusion of Magnesium Shavings." Key Engineering Materials 822 (September 2019): 185–92. http://dx.doi.org/10.4028/www.scientific.net/kem.822.185.
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This article describes the practical application of hot extrusion for compaction of magnesium shavings in semi-finished products and the study of the influence of process parameters on the mechanical properties of the obtained MA5 (AZ80) magnesium alloy bars. Production of bars was carried out at different heating temperatures and plastic deformation degree to find technology provide the best combination of tensile and compressive properties. The resulting bars are somewhat higher in strength characteristics than the strength of deformed cast bars made from MA5 alloy, however, they are significantly lower in ductility.
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Wąsek, Seweryn, Sebastian Mróz, Grzegorz Stradomski, and Konrad Błażej Laber. "The Analysis of Al-Cu Bimetallic Bars Bond Layers Joined by the Explosive Method." Solid State Phenomena 199 (March 2013): 508–13. http://dx.doi.org/10.4028/www.scientific.net/ssp.199.508.
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The paper presents investigation results for obtaining a semi-finished product in the form of round Al-Cu bimetallic bars by the explosion method. The systems and technological parameters of explosion welding were selected in such a manner as to obtain finished bimetallic bars of an outer diameter of approx. 22 mm and a copper area fraction of the bimetal cross-section of approx. 15 and 30%. In this work was made an analysis of microstructure changes and the microhardness distribution on the cross-sections of the stock materials. There were also made tests of layers connections quality by determining the maximum shear stress on the joint boundary. The results show that the explosive cladding method guarantee a permanent connection of copper layers and aluminum core.
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Rubin, Per, Richard Larker, Erik Navara, and Marta Lena Antti. "Novel Cost-Efficient Method of Producing Ausferritic Steels Displaying Excellent Combination of Mechanical Properties." Defect and Diffusion Forum 405 (November 2020): 11–18. http://dx.doi.org/10.4028/www.scientific.net/ddf.405.11.
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Round bars Ø 53 mm were hot-rolled from a 1.4 tonne ingot forged to 165 × 165 mm. The composition of the steel was 0.45 wt. % C and 3.33 wt. % Si plus alloying elements for hardenability. Microstructure after air cooling from 1010 °C on the cooling bed was predominantly ausferritic. Tensile testing of as-rolled bars resulted in yield strength 846 ± 22 MPa, ultimate tensile strength 1169 ± 99 MPa and A5-elongation of 1.7 ± 0.8 % (without prior necking). When as-rolled steel was baked in air at T = {Ms initial -30 K} for six hours, the yield stress raised to 1121 ± 4 MPa, the ultimate tensile stress raised to 1447 ± 5 MPa and the elongation raised to 22.6 ± 1.6 % (with necking > 18 %). For as-rolled bars during continuous cooling, the exposure time within the temperature range 460 – 320 °C was estimated to be about 10 minutes. The microstructure of as-rolled “semi-finished” bars is stable at room temperature. The first baking was done six months after hot-rolling. Optical and scanning electron microscopy showed that remaining areas of austenite, not transformed during continuous cooling but stable at room temperature, transforms to ausferrite when properly baked.
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Bespalov, Vadim, Sergey Sidelnikov, Denis Voroshilov, Yuriy Gorbunov, Igor Konstantinov, Ekaterina Lopatina, Edvard Rudnitskiy, Viktor Berngardt, Olga Yakivyuk, and Alexander Durnopyanov. "Study of the Influence of Conditions of Combined Casting and Rolling-Extruding and Two-Stage Annealing on the Structure and Properties of Semi-Finished Electrical Products from an Al–Zr System Alloy." Key Engineering Materials 805 (June 2019): 19–24. http://dx.doi.org/10.4028/www.scientific.net/kem.805.19.
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This article presents the results of the study of the joint effect of the processing conditions of the new composition of the Al-Zr system alloy by combined casting and rolling-extruding and two-stage annealing on the structure and properties of round bars used in the manufacture of heat-resistant wires. The research show patterns of changes in the properties, the specific electrical resistance of the bars, depending on different conditions of deformation and heat treatment of aluminum alloy with a content of 0.3% zirconium and 0.2% iron. The results of micro-X-ray spectral analysis and the granular structure of the samples before and after two-stage annealing confirming the stability of the structure after heating and preserving the strength of semi-finished products. Presented parameters of combined casting and rolling-extruding and two-stage annealing for the manufacture of rods from the studied alloy make it possible obtaining good combination of mechanical properties and electrical conductivity.
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Ortega, Naiara, Vitaliy Martynenko, Daniela Perez, Daniel Martinez Krahmer, Luis Norberto López de Lacalle, and Eneko Ukar. "Abrasive Disc Performance in Dry-Cutting of Medium-Carbon Steel." Metals 10, no. 4 (April 21, 2020): 538. http://dx.doi.org/10.3390/met10040538.
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Abrasive-cutting processes are widely used to obtain semi-finished products from metal bars, slabs, or tubes. Thus, the abrasive cutting-off process is applied when requiring precision cutting and productivity at a moderate price. Cut-off tools are discs composed of small abrasive particles embedded in a bonding material, called the binder. This work aims to compare the cutting performance of discs with different composition, in dry cutting of steel bars. To do that, disc wear was measured and disc final topography was digitalized in order to determine both disc surface wear patterns and if the abrasive particles bonding into the binder matrix was affected. In addition, X-Ray inspection gave information about the abrasive grit-binder bonding. Therefore, the method here presented allows identifying discs with a superior abrasive-cutting capability, by combining profilometry and tomography to define micrometrical aspects, grit size, and binder matrix structure. Results led to the conclusion that discs with high grit size and protrusion, high grit retention by bond material, and closer mesh of fiberglass matrix binder were the optimal solution.
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Egorova, Yuliia B., Lyudmila V. Davydenko, and Alisa V. Shmyrova. "Predicting Strength of Titanium Alloys Using Aluminum and Molybdenum Equivalents at Operating Temperatures." Defect and Diffusion Forum 410 (August 17, 2021): 15–20. http://dx.doi.org/10.4028/www.scientific.net/ddf.410.15.
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This study contains the results of statistical studies of strength of sheeted products and bars made from α-, near α-, and α+β titanium alloys based on their composition. Based on summarizing the literature data, we have studied the ultimate tensile strength after mill annealing of 30 serial and experimental alloys at testing temperatures between 20 and 600°C. We have also substantiated the possibility to evaluate the tensile strength of semi-finished products using the strength equivalents (such as aluminum and molybdenum) of alloying elements and impurities at various temperatures. We have put forth models that help to predict the ultimate strength of titanium alloys based on their composition and the operating temperature with a confidence level of 0.95 and statistical errors comparable with the regulated spread.
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Mysik, Raisa K., Sergey V. Brusnitsyn, and Andrey V. Sulitsin. "Determination of Thermo-Physical and Physical Properties of Complex Alloyed Brass." Solid State Phenomena 299 (January 2020): 442–46. http://dx.doi.org/10.4028/www.scientific.net/ssp.299.442.
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At present time complex alloyed brasses are widely used for manufacturing of parts worked in fray conditions. The mechanical and service properties of this alloys are provided by presence of different structural constituents in the structure of alloys. The wear resistance is a basic property of complex alloyed brasses. The information on actual problems in the industrial production of cast bars, semi-finished products and [ pfrts]-непонятно] of complex alloyed brasses is presented in the article. In accordance with the increasing requirements of consumers to reliability and service life of parts the complex alloyed brass Cu62Zn31.6Mn3Al2Si0.8Ni0.4Cr0.2 was proposed as a material for production of parts. The development of technology of melting and semi-continuous casting of complex alloyed brass is an important problem. Moreover, for estimation of thermal contition of ingot and simulation of the process of solidification of the ingot, it is necessary to know thermal physic and physical characteristics of an alloy. Therefore, the research on determination of heat conductivity, heat capacity and density of complex alloyed brass, depending on temperature, was carried out. The obtained experimental data can be used to thermos-technical calculation of thermal contition of ingot and simulation of the process of solidification of ingot during semi-continuous casting for the purpose of determination of technological parameters of casting.
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Thiery, D., S. Engineer, H. J. Wieland, and T. Touchard. "“Zero-defect” and ppm strategy for semi-finished steel products, bars and wire rod from the point of view of the steel manufacturers." Revue de Métallurgie 99, no. 1 (January 2002): 55–62. http://dx.doi.org/10.1051/metal:2002106.
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Wang, Quanbin, Deli Jia, Xiaohan Pei, Xuelian Wu, Fan Xu, Huixiong Wang, Minghao Cao, and Haidong Chen. "Investigation of Electromagnetic Pulse Compaction on Conducting Graphene/PEKK Composite Powder." Materials 14, no. 3 (January 30, 2021): 636. http://dx.doi.org/10.3390/ma14030636.
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Polymer-composite materials have the characteristics of light weight, high load, corrosion resistance, heat resistance, and high oil resistance. In particular, graphene composite has better electrical conductivity and mechanical performance. However, the raw materials of graphene composite are processed into semi-finished products, directly affecting their performance and service life. The electromagnetic pulse compaction was initially studied to get the product Graphene/PEKK composite powder. Simultaneously, spark plasma sintering was used to get the bars to determine the electrical conductivity of Graphene/PEKK composite. On the basis of this result, conducting Graphene/PEKK composite powder can be processed by electromagnetic pulse compaction. Finite element numerical analysis was used to obtain process parameters during the electromagnetic pulse compaction. The results show that discharge voltage and discharge capacitance influence on the magnetic force, which is a main moulding factor affecting stress, strain and density distribution on the specimen during electromagnetic pulse compaction in a few microseconds.
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Narayana Murty, S. V. S., and Shiro Torizuka. "Process Design Concepts for the Production of Ultrafine Grained Steels through Multi-Pass Warm Rolling: Bridging Science and Technology." Materials Science Forum 683 (May 2011): 225–31. http://dx.doi.org/10.4028/www.scientific.net/msf.683.225.
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Steel bars having a cross section of 18mm square with uniform distribution of ultrafine ferrite grains were produced through a multi-pass warm caliber rolling process in a 0.15%C-0.3%Si-1.5%Mn steel. The average ferrite grain sizes of 0.43μ m, 0.70μ m and 1.2 μ m were obtained in the isothermal warm caliber rolling processes at 773K, 823K and 873K respectively. Even though caliber rolling results in inhomogeneous strain distribution, multi-pass caliber rolling to large cumulated strains of 2 or 3 can be uniformly introduced in to the bar samples. Strain accumulation due to the multi-pass warm deformations was confirmed by comparing microstructural evolution through the multi-pass deformations with that of single pass deformation. The size of ultrafine grains formed through warm deformation was found to depend on the Zener-Hollomon parameter. The similarity of the microstructural evolution with single pass deformation reveals that the multi-pass warm deformation is an effective method to obtain ultrafine grained ferrite structure in bulk materials. It is proposed that compressive strain-Z parameter plots along with grain size-Z parameter plots help in establishing the processing conditions for obtaining products with a desired microstructure and grain size. Finally, such “processing maps” developed for a variety of materials serve useful purpose in bridging the science and technology of developing bulk ultrafine grained materials in semi-finished / finished products.
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Tamila, V. A. "Design principes of single-stage rolling mills for machine-building industries." Proceedings of the National Academy of Sciences of Belarus, Physical-Technical Series 63, no. 3 (November 1, 2018): 297–306. http://dx.doi.org/10.29235/1561-8358-2018-63-3-297-306.
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The use of variable profiles in engineering is the most effective way to reduce metal consumption and improve performance, increase the lifetime, reliability of machines and mechanisms, and reduce costs for their production, repair and operation. The purpose of the present work is to systematize the blanks of machine-building industries obtained by methods of plastic deformation and to develop general principes of the con cept of creating single-stage rolling mills on the basis of analysis of their design and operation. Three main classes of profiles are distinguished, differing in the type of the initial workpiece: strip, shaped and tube periodic billets. All these types of blanks can be used as semi-finished products for the production of the main parts of suspension and chassis of cars. Strip billets are widely used for the manufacturing of elastic suspension elements, tubular – for manufacturing of hollow body parts with increased requirements for strength and rigidity, in particular, driving axle housing, semi-axles of cars and trailers, jet engine casings. Shaped periodic profiles of various shapes are used as blanks for hot volumetric stamping. Mills and automatic lines for the rolling of blanks of low-spring springs, under-springs, guide bearings of air suspension, rolling of the bars of the front axle beam, manufacturing of protective elements and semi-axes of agricultural machinery developed under the guidance or with the direct participation of the author are presented. General requirements for the deformation equipment of machine-building industries are formulated. Recommendations to use induction heating and high-temperature thermomechanical treatment are justified. It is not recommended to change the direction of movement of the workpiece in the process chain. As a power drive equipment it is better to take electromechani cal, rather than hydraulic systems. It is also advisable to choose separate drives for each working element of the equipment.
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Černý, Michal, Josef Filípek, Pavel Mazal, and Petr Dostál. "Basic mechanical properties of layered steels." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 61, no. 1 (2013): 25–38. http://dx.doi.org/10.11118/actaun201361010025.
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This article deals with identifying attributes of layered steel materials (damask steel) with the help of mechanical tests. Experimentally verify basic mechanical properties of layered steel and subsequently assessed it in comparison with the values obtained for the classic steel materials. In conclusion, there are listed the possibilities of using multilayer steel materials in technical practice, depending on the economics of production.The damask steel was prepared by forge welding from a packet consisting of 17 layers (9 layers of tool steel 19 133 (ČSN) with the thickness of 6 mm and 8 layers 80NiCr11 steel in the form of saw bands with the thickness of 1.2 mm. The packet was cut into 8 parts, folded 3 times and forged together, which provided damask steel with 136 layers. The resulting steel bars were used to make semi-finished products with the approximate dimensions of the test specimens. For evaluation of mechanical properties were applied the following tests: tensile test, Charpy impact test, hardness and microhardness measurementsThe results of tests proved that the properties of damask steel are dependent not only on the direction led impact quality forge weld layers and content iof nhomogeneities in the place of discord, but also on the quenching and tempering temperature, resp. on the choice of quenching bath, which determine the final structure of steel and the resulting hardness, respectively microhardness.
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Kashapov, O. S., T. V. Pavlova, V. S. Kalashnikov, and K. G. Lysov. "Experience in Manufacturing Titanium Alloy Forgins in VIAM Plant Conditions." Herald of the Bauman Moscow State Technical University. Series Mechanical Engineering, no. 1 (136) (March 2021): 133–55. http://dx.doi.org/10.18698/0236-3941-2021-1-133-155.
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The purpose of the study was to reveal the effect of various technological aspects of manufacturing titanium alloy ВТ8 (VT8) forgings under isothermal conditions on a press with a force of 1600 kN. The starting material was OST 1 90266--86 and OST 1 90107--73 VT8 (ВТ8) alloy bars. For the forgings obtained from these rods, the score and background of the macrostructure, the type of microstructure, short-term strength, elongation, contraction and impact toughness at room temperature were determined. For forgings made from an OST 1 90266--86 bar, the effect of thermomechanical treatment on the level of properties was additionally evaluated, namely, half of the forging was recalibrated. The microstructure of the forgings which were made by thermomechanical treatment and aged was additionally investigated using scanning electron microscopy. Findings of research show a direct dependence of the quality of the final semi-finished product on the quality of the original bar. It has been established that lowering the punching temperature to the level of Tpp -- 150 °С leads to insufficient development of the structure of the deformed material over the cross section, and results in the presence of large grains from the initial bar. So, on forgings made from an OST 1 90266--86 bar, the following level of mechanical properties was achieved: σv ≥ 1000 MPa, δ ≥ 11 %, ψ ≥ 20 %, KCU ≥ 40.3 J / cm2
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Mysik, R. K., A. V. Sulitsin, and S. V. Brusnitsyn. "Influence of Intermetallics on Complex Alloyed Brass Hardness." Solid State Phenomena 265 (September 2017): 789–92. http://dx.doi.org/10.4028/www.scientific.net/ssp.265.789.
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The results of the study of phase composition, structure, and properties of multi-component complex alloyed wear-resistant brass are presented. The material contains aluminium, manganese, silicon, nickel, and chromium besides copper and zinc. A review of the influence of these components on the formation of intermetallics with different chemical composition and morphology is made. Based on the analysis it is revealed that the wear resistance of brass is highly dependent on the ratio of α-and β-phases and the volume fraction of the intermetallic particles. Chemical X-ray fluorescence, scanning electron microscopy (SEM) and electron-probe microanalysis (EPMA) are used. Based on the experiments it is established that alloys without chromium contain rod-shaped intermetallics based on Mn-Si compound with a ratio of length to cross sectional dimension 2–4. These intermetallics create the effect of anisotropy in an alloy. The presence of chromium in an alloy leads to the formation of equiaxial intermetallics with the chromium silicide core and manganese silicide coat; in this case the alloy is isotropic. It is established with metallographic study that the density of intermetallic compounds distribution of 50–130 thousand particles per 1 mm3 is required to archive the 291–298 HB hardness of brass. Cast ingots are made following the semi-casting method and then pressed to tube bars; the finished products are made by stamping so, the production technology can improve the mechanical characteristics of alloy.
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Sidelnikov, Sergey, Ruslan Sokolov, Denis Voroshilov, Mikhail Motkov, Vadim Bespalov, Marina Voroshilova, Svetlana Sokolova, Edvard Rudnitskiy, Olga Lebedeva, and Vera Borisyuk. "Modeling the Process of Obtaining Bars from Aluminum Alloy 01417 by Combined Rolling-Extruding Method with Application of the Deform-3D Complex." Key Engineering Materials 861 (September 2020): 540–46. http://dx.doi.org/10.4028/www.scientific.net/kem.861.540.
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The results of computer simulation of the process of combined rolling-extruding of longish deformed semi-finished products from alloy 01417 are presented. A feature of the research is that continuously cast bars with a diameter of 12.5 mm obtained using an electromagnetic mold are used as a workpiece. This makes it possible to increase the manufacturability of processing and to obtain after rolling-extruding billets for drawing with a diameter of 5 mm with a large resource of plastic and strength properties. For this case the technological parameters and temperature and speed conditions of combined processing have not yet been studied, therefore, their analysis was performed using the Deform-3D software package. It has been revealed that the feasibility of the rolling-extruding process is significantly affected by the frequency of rotation of the rolls. Moreover, the process becomes unstable when the value of this parameter is 4 rpm, which can be explained by insufficient degrees of deformation during rolling, and consequently by the small value of the active friction forces acting on the contact surface of the metal with the rolls. As a result of this, the processing temperature conditions also change, which is also demonstrated using the developed computer model. As a result, it was found that for the stable course of the combined rolling-extruding process at the CRE-200 unit of a continuously cast billet with a diameter of 12.5 mm from alloy 01417 at a heating temperature of the billet of 550 °C and a tool of 200 °C, degree of deformation during rolling 44% and drawing ratio during extruding 18.6 the frequency of rotation of the rolls should be at least 8 rpm. The simulation data used during the implementation of the process at the combined processing unit CRE-200, the results of which made it possible to finally obtain electrotechnical wire with a diameter of 0.5 mm from 01417 alloy that meets the requirements of TS 1-809-63-2018.
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Koroleva, Tatiana A., Lyubov A. Milovidova, and Andrey A. Dryakhlitsyn. "Production of High-Yield Hardwood Pulp by Bisulfite Minimizing the Chlorine Content Cooking." Lesnoy Zhurnal (Forestry Journal), no. 3 (May 20, 2021): 161–69. http://dx.doi.org/10.37482/0536-1036-2021-3-161-169.
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The article presents the results of the development of a technological mode for obtaining bisulfite hardwood pulp of high yield on a magnesium base for the production of various types of containerboard. The reliable and effective chemical and heat recovery technology implemented in the bisulfite method allows to use it in independent sulfite process. The effect of the duration of stay at the final temperature on the pulp yield and kappa number was studied when developing the technological mode of cooking. It was found that the increase in the duration of stay at the final temperature of 160 °C more than 40 min leads to violations of the selectivity of the cooking process. Increasing the duration of stay at the final temperature up to 70 min is accompanied by a decrease in pulp yield by 6 % at a constant value of the kappa number of the semi-finished product. Technological cooking mode: hydromodule 5, SO2 consumption 15.0 %, cooking solution pH 4.3–4.5, impregnation time at 120 °C – 35 min, cooking duration at 160 °C – 40 min. The mode allows to get a semi-finished product with a high yield of 60–65 % with a kappa number of 58–60 units without a hot grinding stage. An assessment of the mechanical strength characteristics of the laboratory samples of bisulfite pulp was carried out in accordance with the standards of the Russian Federation. The obtained values of bursting strength, resistance to flat compression, breaking strength, and breaking stress were comparable with the values of the industrial sample of hardwood neutral sulfite semi-chemical pulp with a semi-finished product yield of 75–78 %. It is shown that the presence of bark in the technological chips in the amount of 7.5 % is accompanied by a decrease in the yield of bisulfite hardwood pulp by 4.5 % and mechanical strength by 7.8 %. For citation: Koroleva T.A., Milovidova L.A., Dryakhlitsyn A.A. Production of High-Yield Hardwood Pulp by Bisulfite Cooking. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 3, pp. 161–169. DOI: 10.37482/0536-1036-2021-3-161-169
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Chugunova, O. V., D. V. Graschenkov, and A. V. Vyatkin. "Application of fruit and berry raw materials in hot drink recipes." Processes and Food Production Equipment 10, no. 4 (December 15, 2020): 39–52. http://dx.doi.org/10.17586/2310-1164-2020-10-4-39-52.
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The article presents research on the development of organoleptically compatible recipes and technologies for hot drinks of the pronounced antioxidant properties based on fruits and berries of varieties growing in the Sverdlovsk region with the addition of English Breakfast black tea, Earl Gray black tea, Tie Guan Yin green tea, Milk Oolong green tea, and Sencha green tea, as well as various brands of tea blends and tea-bags. In addition, we used dried medicinal and technical raw materials and spices. It was found that the values of the antioxidant activity (AOA) of tea bags and tea drinks are in the range from 0.274 to 12.809 mmol-eq/dm3; in the pekoe teas they are in the range from 9.375 to 14.531 mmol-eq/dm3; in the raw materials of plant origin growing in the Sverdlovsk region they are from 0.513 to 8.227 mmol-eq/dm3. The greatest total antioxidant activity has been observed in: Prevoshodnaya sea buckthorn cultivar– 2.204 mmol-eq/dm3; Vladimirskaya cherry variety – 4.971 mmol-eq/dm3; Chernoplodnaya aronia variety – 8.026 mmol-eq/dm3; Globus black currant variety– 8.227 mmol-eq/dm3. According to the research results, the total AOA value for developed hot drinks prepared from fresh fruits and berries was from 13.641 to 20.815 mmol-eq/dm3, and for hot drinks prepared on the basis of Frozen semi-finished product from fruits and berries – from 13.576 to 20.772 mmol-eq/dm3, which is 42-65% of the recommended daily consumption rate in terms of ascorbic acid (ascorbic acid AOA values – 32.024 ± 0.350 mmol – eq/dm3). The developed hot drinks have high values of antioxidant activity, which means that they can increase the amount of antioxidants in the diet of consumers and thereby reduce the negative impact of oxidative stress. The proposed technique of hot drinks manufacturing with the use of frozen semi-finished product allows to increase the rate of technological process significantly.
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Mojzes, Ákos, Barnabás Tóth, and Péter Csavajda. "Investigation of an Electrostatic Discharge Protective Biodegradable Packaging Foam in the Logistic Chain." Logistics & sustainable transport 5, no. 1 (November 1, 2014): 25–33. http://dx.doi.org/10.1515/jlst-2015-0004.
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Abstract Since the beginning of the 20th century, logistics has undergone a huge technological development, which has, however, resulted in many negative effects as well. The industry, particularly in the packaging industry has been a massive waste producer, although recently it has forced the use of new materials and it started to focus on environmentally friendly technologies. During the transportation of finished and semi-finished Electrostatic Discharge (ESD) sensitive products, the product packaging system has a vital role. These kind of packaging materials must be suitable to both logistic (protection against mechanical and environmental stresses) and special ESD protection requirements. During the transportation of printed-circuit electronic products, ESD defense is then of primary significance. However there is a huge disadvantage for the use of various shield bags. Namely, this kind of associated packaging is particularly pollutant, it causes a lot of inconvenience in the form of waste. In order to rule out these materials from the packaging system, new innovative solutions have to be found. The investigated TPS (thermoplastic starch biodegradable foam) is subjected to a validation, a long process to certify that this material unites properties of two types of packaging materials at the same time. On the one hand, this packaging foam has to meet the requirements product defense. On the other hand, the material must be anti-static under the logistic stress effects. In case it is found suitable, it can be an alternative of the conventional materials. In this article, we investigate the ESD characteristic of TPS foam. As this material sensitive for environmental parameters during transportation, we make the relevant Surface Resistance (Rs) tests on different temperature and humidity conditions. Based on result, the decision of the application can be done, as an ESD packaging material.
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Bader, Fabian, Lukas Bathelt, Eugen Djakow, Werner Homberg, Christian Henke, and Ansgar Trächtler. "Innovative Measurement Of Stress Superposed Steel Strip For Straightening Machines." ESAFORM 2021, March 29, 2021. http://dx.doi.org/10.25518/esaform21.2382.
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Higher quality requirements by customers demand higher precision and accuracy from manufacturing processes. Application oriented preparation of semi-finished materials is key for subsequent forming operations, therefore, straightening machines are employed. Straightening strengthens the material by increasing plastic deformation by means of strain hardening, resulting in undesirable reduction in formability when processing high strength materials, in particular. Conventional roll-type straightening machines process either bars or strips. This is achieved upon passing material between rolls arranged in two staggered rows. However, conventional straightening processes do not adapt to the local varying distortion of coiled strips. Innovative, self-correcting process control techniques, which adapt to the initial geometric characteristics of the strip, present a promising approach to fix this issue through optimization of the leveling process. Here, an innovative strategy to improve straightening of high strength steel materials (1.4310) is presented. This implements optimized leveling, adding minimal plastic deformation and, thus, strain hardening. To operate an intelligent straightening machine, a reliable online measurement of the surface defects is fundamentally essential. The MagnaTest, which is developed for material testing, is made feasible for such purposes after calibrating for curvature measurement. Preliminary results are promising in regards to measuring the curvature online, so that the following straightening process can be close loop controlled. The bending measurement is linked to open/closed loop control, therefore providing an optimal straightening result in regards to formability, leveling, and reduced strain hardening.