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Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing
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作者 Pavlo Markovsky Jacek Janiszewski +5 位作者 Dmytro Savvakin Oleksandr Stasyuk Bartosz Fikus Victor Samarov Vianey Ellison Sergey V.Prikhodko 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期1-14,共14页
Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded to... Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP).The laminates were ballistically tested and demonstrated superior performance.The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates.The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate.Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP,which provides an unprecedented increase in the hardness of the layered composites.It is argued that the combination of the used two technologies,BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually. 展开更多
关键词 Metal matrix composites powder metallurgy Titanium hydride powder Master alloy Titanium carbide Titanium boride Hot isostatic pressing Ballistic tests
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Integrated high-performance and accurate shaping technology of low-cost powder metallurgy titanium alloys: A comprehensive review
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作者 Xuemeng Gan Shaofu Li +1 位作者 Shunyuan Xiao Yafeng Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期413-426,共14页
The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O ... The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review. 展开更多
关键词 powder metallurgy titanium sintering densification oxygen scavenging accurate shaping
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Microstructure evolution and strengthening mechanism of high -performance powder metallurgy TA15 titanium alloy by hot rolling
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作者 Ying Gao Ce Zhang +1 位作者 Jiazhen Zhang Xin Lu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1426-1436,共11页
Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying alloys.In this study,Ti–6.5Al–2Zr–Mo–V(TA15)titaniu... Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying alloys.In this study,Ti–6.5Al–2Zr–Mo–V(TA15)titanium alloy plates were prepared by cold press-ing sintering combined with high-temperature hot rolling.The microstructure and mechanical properties under different process paramet-ers were investigated.Optical microscope,electron backscatter diffraction,and others were applied to characterize the microstructure evolution and mechanical properties strengthening mechanism.The results showed that the chemical compositions were uniformly dif-fused without segregation during sintering,and the closing of the matrix craters was accelerated by increasing the sintering temperature.The block was hot rolled at 1200℃ with an 80%reduction under only two passes without annealing.The strength and elongation of the plate at 20–25℃ after solution and aging were 1247 MPa and 14.0%,respectively,which were increased by 24.5%and 40.0%,respect-ively,compared with the as-sintered alloy at 1300℃.The microstructure was significantly refined by continuous dynamic recrystalliza-tion,which was completed by the rotation and dislocation absorption of the substructure surrounded by low-angle grain boundaries.After hot rolling combined with heat treatment,the strength and plasticity of PM-TA15 were significantly improved,which resulted from the dense,uniform,and fine recrystallization structure and the synergistic effect of multiple slip systems. 展开更多
关键词 elemental powder powder metallurgy titanium alloy hot rolling strength and plasticity
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Ceramic particles reinforced copper matrix composites manufactured by advanced powder metallurgy:preparation, performance, and mechanisms 被引量:4
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作者 Yi-Fan Yan Shu-Qing Kou +4 位作者 Hong-Yu Yang Shi-Li Shu Feng Qiu Qi-Chuan Jiang Lai-Chang Zhang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第3期200-234,共35页
Copper matrix composites doped with ceramic particles are known to effectively enhance the mechanical properties,thermal expansion behavior and high-temperature stability of copper while maintaining high thermal and e... Copper matrix composites doped with ceramic particles are known to effectively enhance the mechanical properties,thermal expansion behavior and high-temperature stability of copper while maintaining high thermal and electrical conductivity.This greatly expands the applications of copper as a functional material in thermal and conductive components,including electronic packaging materials and heat sinks,brushes,integrated circuit lead frames.So far,endeavors have been focusing on how to choose suitable ceramic components and fully exert strengthening effect of ceramic particles in the copper matrix.This article reviews and analyzes the effects of preparation techniques and the characteristics of ceramic particles,including ceramic particle content,size,morphology and interfacial bonding,on the diathermancy,electrical conductivity and mechanical behavior of copper matrix composites.The corresponding models and influencing mechanisms are also elaborated in depth.This review contributes to a deep understanding of the strengthening mechanisms and microstructural regulation of ceramic particle reinforced copper matrix composites.By more precise design and manipulation of composite microstructure,the comprehensive properties could be further improved to meet the growing demands of copper matrix composites in a wide range of application fields. 展开更多
关键词 copper matrix composites advanced powder metallurgy model prediction particle characteristics strengthening mechanism
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Deformation behaviors and processing maps of CNTs/Al alloy composite fabricated by flake powder metallurgy 被引量:2
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作者 何维均 李春红 +4 位作者 栾佰峰 邱日盛 王柯 李志强 刘庆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3578-3584,共7页
Deformation behaviors of CNTs/Al alloy composite fabricated by the method of flake powder metallurgy were investigated by hot compression tests, which were performed in the temperature range of 300?550 °C and str... Deformation behaviors of CNTs/Al alloy composite fabricated by the method of flake powder metallurgy were investigated by hot compression tests, which were performed in the temperature range of 300?550 °C and strain rate range of 0.001? 10 s?1 with Gleeble?3500 thermal simulator system. Processing maps of the CNTs/Al alloy at different strains were calculated to study the optimum processing domain. Microstructures before and after hot compressions were characterized by electron backscattered diffraction (EBSD) method. Stress?strain curves indicate that the flow stress increases with the increase of strain rate and the decrease of temperature. The processing maps of the CNTs/Al alloy at different strains show that the optimum processing domain is 500?550 °C, 10 s?1 for hot working. EBSD analysis demonstrates that fully dynamic recrystallization occurs in the optimum processing domain (high strainrate 10 s?1), whereas the main soften mechanism is dynamic recovery at low strain rate (0.001 s?1). 展开更多
关键词 CNTs/Al alloy composite flake powder metallurgy recrystallization processing map flow stress
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Phase transformation and damping behavior of lightweight porous TiNiCu alloys fabricated by powder metallurgy process 被引量:2
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作者 江鸿杰 柯常波 +2 位作者 曹姗姗 马骁 张新平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2029-2036,共8页
Porous TiNiCu ternary shape memory alloys (SMAs) were successfully fabricated by powder metallurgy method. The microstructure, martensitic transformation behavior, damping performance and mechanical properties of th... Porous TiNiCu ternary shape memory alloys (SMAs) were successfully fabricated by powder metallurgy method. The microstructure, martensitic transformation behavior, damping performance and mechanical properties of the fabricated alloys were intensively studied. It is found that the apparent density of alloys decreases with increasing the Cu content, the porous Ti50Ni40Cu10 alloy exhibits wide endothermic and exothermic peaks arisen from the hysteresis of martensitic transformations, while the porous Ti50Ni30Cu20 alloy shows much stronger and narrower endothermic and exothermic peaks owing to the B2-B19 transformation taking place easily. Moreover, the porous Ti50Ni40Cu10 alloy shows a lower shape recovery rate than the porous Ti50Ni50 alloy, while the porous Ti50Ni30Cu20 alloy behaves reversely. In addition, the damping capacity (or internal friction, IF) of the porous TiNiCu alloys increases with increasing the Cu content. The porous Ti50Ni30Cu20 alloy has very high equivalent internal friction, with the maximum equivalent internal friction value five times higher than that of the porous Ti50Ni50 alloy. 展开更多
关键词 porous TiNiCu alloys powder metallurgy martensitic transformation damping behavior
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Hot deformation and processing maps of Al_2O_3/Al composites fabricated by flake powder metallurgy 被引量:1
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作者 栾佰峰 邱日盛 +4 位作者 李春红 杨晓芳 李志强 张荻 刘庆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1056-1063,共8页
The deformation behaviors of Al2O3/Al composites were investigated by compressive tests conducted at temperature of 300-450 °C and strain rates of 0.001-1.0 s-1 with Gleeble-1500 D thermal simulator system. The r... The deformation behaviors of Al2O3/Al composites were investigated by compressive tests conducted at temperature of 300-450 °C and strain rates of 0.001-1.0 s-1 with Gleeble-1500 D thermal simulator system. The results show that the flow stress increases with increasing strain rate and decreasing temperature. The hyperbolic sine constitutive equation can describe the flow stress behavior of Al2O3/Al composites, and the deformation activation energy and constitutive equations were calculated. The processing maps of Al2O3/Al-2 μm and Al2O3/Al-1 μm composites at strain of 0.6 were obtained and the optimum processing domains are in ranges of 300-330 °C, 0.007-0.03 s-1 and 335-360 °C, 0.015-0.06 s-1 for hot working, respectively. The instability zones of flow behavior can also be recognized by the maps. 展开更多
关键词 Al2O3/Al composites flake powder metallurgy flow stress processing map
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Effect of milling time on microstructure of Ti35Nb2.5Sn/10HA biocomposite fabricated by powder metallurgy and sintering 被引量:1
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作者 王晓鹏 徐丽娟 +4 位作者 陈玉勇 禹基道 肖树龙 孔凡涛 刘志光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期608-612,共5页
A new β-Ti based Ti35Nb2.5Sn/10 hydroxyapitite(HA) biocompatible composite was fabricated by mechanical milling and pulsed current activated sintering(PCAS).The microstructures of Ti35Nb2.5Sn/10HA powder particle... A new β-Ti based Ti35Nb2.5Sn/10 hydroxyapitite(HA) biocompatible composite was fabricated by mechanical milling and pulsed current activated sintering(PCAS).The microstructures of Ti35Nb2.5Sn/10HA powder particles and composites sintered from the milled powders were studied.Results indicated that α-Ti phase began to transform into β-Ti phase after the powders were mechanically milled for 8 h.After mechanical milling for 12 h,α-Ti completely transformed into β-Ti phase,and the ultra fine Ti35Nb2.5Sn/10HA composite powders were obtained.And ultra fine grain sized Ti35Nb2.5Sn/10HA sintered composites were obtained by PCAS.The hardness and relative density of the sintered composites both increased with increasing the ball milling time. 展开更多
关键词 Ti35Nb2.5Sn/10HA ultrafine grain powder metallurgy milling time
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Microstructure and mechanical properties of powder metallurgy Ti-Al-Mo-V-Ag alloy
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作者 肖代红 袁铁锤 +1 位作者 欧小琴 贺跃辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1269-1276,共8页
The Ti-Al-Mo-V-Ag α+β alloys were processed by powder metallurgy(PM) using the blended elemental(BE) technique.The effects of Ag addition and sintering temperature on microstructure and properties of the Ti-5Al... The Ti-Al-Mo-V-Ag α+β alloys were processed by powder metallurgy(PM) using the blended elemental(BE) technique.The effects of Ag addition and sintering temperature on microstructure and properties of the Ti-5Al-4Mo-4V alloys were investigated using X-ray diffraction,optical microscope,scanning electron microscope and mechanical properties tests.The results show that adding Ag element increases the relative density and improves the mechanical properties of PM Ti-5Al-4Mo-4V alloy.After sintering at 1 250 ℃ for 4 h,the relative density and compression strength of Ti-5Al-4Mo-4V-5Ag alloy are 96.3% and 1 656 MPa,respectively. 展开更多
关键词 titanium alloys powder metallurgy(PM) AG microstructure mechanical properties
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Effect of glass fibre(GF) addition on microstructure and tensile property of GF/Pb composites fabricated by powder metallurgy
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作者 耿耀宏 王蓬瑚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第10期2672-2678,共7页
GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre (GF). The results show that rel... GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre (GF). The results show that relative densities decrease with increasing GF fraction, and the 50μm-GF reinforced specimens exhibit a better densification than the 300μm-GF reinforced ones. The GF particles distribute quite uniformly inPb matrix, and the composites fabricated at low sintering temperature (〈200℃) possess fine-grain microstructure. The addition of GF significantly improves the strength of the Pb composites, and the ultimate tensile strength of the Pb composite reinforcedwith the addition of 50μm-0.5% GF(mass fraction)is about 30MPa higher than that of GF-free sample. For all composites groups, increasing the reinforcement content from 0.5%to 2%(mass fraction)results in a decrease in both tensile strength and ductility. 展开更多
关键词 GF/Pb composites powder metallurgy sintering microstructure tensile property
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Damping capacity of high strength-damping aluminum alloys prepared by rapid solidification and powder metallurgy process 被引量:6
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作者 李国丛 马岳 +2 位作者 何晓磊 李伟 李沛勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1112-1117,共6页
Two kinds of high strength-damping aluminum alloys (LZ7) were fabricated by rapid solidification and powder metallurgy (RS-PM) process. One material was extruded to profile aluminum directly and the other was extr... Two kinds of high strength-damping aluminum alloys (LZ7) were fabricated by rapid solidification and powder metallurgy (RS-PM) process. One material was extruded to profile aluminum directly and the other was extruded to bar and then rolled to sheet. The damping capacity over a temperature range of 25-300 ℃was studied with damping mechanical thermal analyzer (DMTA) and the microstructures were investigated by optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results show that the damping capacity increases with the test temperature elevating. Internal friction value of rolled sheet aluminum is up to 11.5×10^-2 and that of profile aluminum is as high as 6.0×10^-2 and 7.5×10^-2 at 300 ℃, respectively. Microstructure analysis shows the shape of precipitation phase of rolled alloy is more regular and the distribution is more homogeneous than that of profile alloy. Meanwhile, the interface between particulate and matrix of rolled sheet alloy is looser than that of profile alloy. Maybe the differences at interface can explain why damping capacity of rolled sheet alloy is higher than that of profile alloys at high temperature (above 120 ℃). 展开更多
关键词 damping capacity rapid solidification and powder metallurgy process composite materials damping mechanism
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Fabrication of homogeneously dispersed graphene/Al composites by solution mixing and powder metallurgy 被引量:13
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作者 Xiang Zeng Jie Teng +3 位作者 Jin-gang Yu Ao-shuang Tan Ding-fa Fu Hui Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第1期102-109,共8页
Graphene-reinforced aluminum (AI) matrix composites were successfully prepared via solution mixing and powder metallurgy in this study. The mechanical properties of the composites were studied using microhardness an... Graphene-reinforced aluminum (AI) matrix composites were successfully prepared via solution mixing and powder metallurgy in this study. The mechanical properties of the composites were studied using microhardness and tensile tests. Compared to the pure Al alloy, the graphene/Al composites showed increased strength and hardness. A tensile strength of 255 MPa was achieved for the graphene/Al com- posite with only 0.3wt% graphene, which has a 25% increase over the tensile strength of the pure Al matrix. Raman spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to investigate the morphol- ogies, chemical compositions, and microstructures of the graphene and the graphene/A1 composites. On the basis of fractographic evidence, a relevant fracture mechanism is proposed. 展开更多
关键词 GRAPHENE metal matrix composites solution mixing powder metallurgy mechanical properties
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Age-hardening behavior and microstructure of Cu-15Ni-8Sn-0.3Nb alloy prepared by powder metallurgy and hot extrusion 被引量:10
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作者 Yi OUYANG Xue-ping GAN +4 位作者 Shi-zhong ZHANG Zhou LI Ke-chao ZHOU Ye-xin JIANG Xian-wei ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第9期1947-1955,共9页
Cu-15Ni-8Sn-0.3Nb alloy rods were prepared by means of powder metallurgy followed by hot extrusion.Element maps obtained by electron probe micro analyzer(EPMA)showed that Nb-rich phases were formed and distributed wit... Cu-15Ni-8Sn-0.3Nb alloy rods were prepared by means of powder metallurgy followed by hot extrusion.Element maps obtained by electron probe micro analyzer(EPMA)showed that Nb-rich phases were formed and distributed within grains and at grain boundaries of the Cu-15Ni-8Sn-0.3Nb alloy.Transmission electron microscope(TEM)results indicated that there was no obvious orientation relationship between these phases and the matrix.Spinodal decomposition and ordering transformation appeared at early stages of aging at400°C and caused significant strengthening.Cu-15Ni-8Sn-0.3Nb alloy exhibited both higher strength(ultimate tensile strength>1030MPa)and higher tensile ductility(elongation>9.1%)than Cu-15Ni-8Sn alloy after aging treatment.The improvement was caused by Nb-rich phases at grain boundaries which led o the refinement of grain size and postponed the growth of discontinuous precipitates during aging. 展开更多
关键词 Cu-15Ni-8Sn-0.3Nb alloy powder metallurgy method hot extrusion aging treatment spinodal decomposition MICROSTRUCTURE mechanical properties
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New development of powder metallurgy in automotive industry 被引量:9
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作者 TAN Zhao-qiang ZHANG Qing +3 位作者 GUO Xue-yi ZHAO Wei-jiang ZHOU Cheng-shang LIU Yong 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第6期1611-1623,共13页
The driving force for using powder metallurgy(PM)mostly relies on its near net-shape ability and cost-performance ratio.The automotive application is a main market of PM industry,requiring parts with competitive mecha... The driving force for using powder metallurgy(PM)mostly relies on its near net-shape ability and cost-performance ratio.The automotive application is a main market of PM industry,requiring parts with competitive mechanical or functional performance in a mass production scale.As the automobile technology transforms from traditional internal combustion engine vehicles to new energy vehicles,PM technology is undergoing significant changes in manufacturing and materials development.This review outlines the challenges and opportunities generated by the changes in the automotive technology for PM.Low-cost,high-performance and light-weight are critical aspects for future PM materials development.Therefore,the studies on PM lean-alloyed steel,aluminum alloys,and titanium alloy materials were reviewed.In addition,PM soft magnetic composite applied to new energy vehicles was discussed.Then new opportunities for advanced processing,such as metal injection molding(MIM)and additive manufacturing(AM),in automotive industry were stated.In general,the change in automotive industry raises sufficient development space for PM.While,emerging technologies require more preeminent PM materials.Iron-based parts are still the main PM products due to their mechanical performance and low cost.MIM will occupy the growing market of highly flexible and complex parts.AM opens a door for fast prototyping,great flexibility and customizing at low cost,driving weight and assembling reduction. 展开更多
关键词 AUTOMOTIVE powder metallurgy lean alloy Al alloy Ti alloy metal injection molding additive manufacturing
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Effect of Die Wall Lubrication on Warm Compaction Powder Metallurgy 被引量:13
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作者 LI Yuan-yuan, NGAI Tungwai Leo, ZHANG Da-tong, LONG Yan, XIA Wei (College of Mechanical Engineering, South China University of Technology, Guangzhou 510640, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期45-46,共2页
Die wall lubrication was applied on warm compaction powder metallurgy in hope to reduce the concentration level of the admixed lubricant since lubricant is harmful to the mechanical property of the sintered materials.... Die wall lubrication was applied on warm compaction powder metallurgy in hope to reduce the concentration level of the admixed lubricant since lubricant is harmful to the mechanical property of the sintered materials. Iron-based samples were prepared by die wall lubricated warm compaction at 135 ℃ and 175 ℃, using polytetrafluoroethylene (PTFE) emulsion as die wall lubricant. A compacting pressure of 700 MPa and 550 MPa were used. The admixed lubricant concentration ranging from 0 to 0.6 wt.% was used in this study. Compared with non-die wall lubricated samples, the die wall lubricated samples have higher green densities. Results show that in addition to the decrease in ejection forces, green density of the compacts increased linearly with the decrease in admixed lubricant content. Mechanical property of the sintered compacts increase sharply when the admixed lubricant concentration reduced to 0.125 wt.% or less. Ejection force data indicated that samples with die wall lubrication show lower ejection forces when compared with samples without die wall lubrication. No scoring was observed in all experiments even for samples contain no admixed lubricant. Our results indicated that under experimental condition used in this study, no matter at which compaction pressure, compaction temperature, graphite and lubricant contents in the powder the die wall lubricated warm compaction would give the highest green density and lowest ejection force. It can be concluded that combination of die wall lubrication and warm compaction can provide P/M products with higher density and better quality. It is a feasible way to produce high performance P/M parts if suitable die wall lubrication system was applied. 展开更多
关键词 warm compaction die wall lubrication powder metallurgy
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Comparison of Cu−Al−Ni−Mn−Zr shape memory alloy prepared by selective laser melting and conventional powder metallurgy 被引量:8
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作者 Dennis GERA Jonadabe SANTOS +1 位作者 Cláudio SKIMINAMI Piter GARGARELLA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第12期3322-3332,共11页
This work aimed to investigate and critically analyze the differences in microstructural features and thermal stability of Cu−11.3Al−3.2Ni−3.0Mn−0.5Zr shape memory alloy processed by selective laser melting(SLM)and co... This work aimed to investigate and critically analyze the differences in microstructural features and thermal stability of Cu−11.3Al−3.2Ni−3.0Mn−0.5Zr shape memory alloy processed by selective laser melting(SLM)and conventional powder metallurgy.PM specimens were produced by sintering 106−180μm pre-alloyed powders under an argon atmosphere at 1060°C without secondary operations.SLM specimens were consolidated through melting 32−106μm pre-alloyed powders on a Cu−10Sn substrate.Mechanical properties were measured through Vickers hardness testing.Differential scanning calorimetry was conducted to assess the martensitic transformation temperatures.X-ray diffraction patterns were collected to identify the metallurgical phases.Optical and scanning electron microscopy was used to analyze the microstructural features.b′1 martensite was found,irrespective of the processing route,although coarser martensitic variants were present in PM-specimens.In conventional powder metallurgy samples,intergranular eutectoid constituents and stabilized austenite also formed at room temperature.PM-specimens showed similar average hardness values to the SLM-specimens,albeit with high standard deviation linked to the porosity.The specimens processed by SLM showed reversible martensitic transformation(T0=171°C).PM-processed specimens did not show shape memory effects. 展开更多
关键词 shape memory alloys powder metallurgy additive manufacturing selective laser melting Cu-based alloys
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Effect of inclusion size on the high cycle fatigue strength and failure mode of a high V alloyed powder metallurgy tool steel 被引量:6
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作者 Jun Yao Xuan-hui Qu Xin-bo He Lin Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第7期608-614,共7页
The fatigue strength of a high V alloyed powder metallurgy tool steel with two different inclusion size levels, tempered at different temperatures, was investigated by a series of high cycle fatigue tests. It was show... The fatigue strength of a high V alloyed powder metallurgy tool steel with two different inclusion size levels, tempered at different temperatures, was investigated by a series of high cycle fatigue tests. It was shown that brittle inclusions with large sizes above 30μm prompted the occurrence of subsurface crack initiation and the reduction in fatigue strength. The fracture toughness and the stress amplitude both exerted a significant influence on the fish-eye size. A larger fish-eye area would form in the sample with a higher fracture toughness subjected to a lower stress amplitude. The stress intensity factor of the inclusion was found to lie above a typical value of the threshold stress intensity factor of 4 MPa.m^1/2. The fracture toughness of the sample with a hardness above HRC 56 could be estimated by the mean value of the stress intensity factor of the fish-eye. According to fractographic evaluation, the critical inclusion size can be calculated by linear fracture mechanics. 展开更多
关键词 powder metallurgy tool steel fatigue of materials strength of materials failure modes INCLUSIONS FRACTOGRAPHY
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Effects of foaming parameters on microstructure and compressive properties of aluminum foams produced by powder metallurgy method 被引量:6
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作者 T.GERAMIPOUR H.OVEISI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第7期1569-1579,共11页
Semi open-cell aluminum foams having channels between individual cells were produced using low cost CaCO3foamingagent and applying the powder compact melting process.To this end,the aluminum and CaCO3powder mixtures w... Semi open-cell aluminum foams having channels between individual cells were produced using low cost CaCO3foamingagent and applying the powder compact melting process.To this end,the aluminum and CaCO3powder mixtures were coldcompacted into dense cylindrical precursors for foaming at specific temperatures under air atmosphere.The effects of severalparameters including precursor compaction pressure,foaming agent content as well as temperature and time of the foaming processon the cell microstructure,linear expansion,relative density and compressive properties were investigated.A uniform distribution ofcells with sizes less than100μm,which form semi open-cell structures with relative densities in the range of55.4%-84.4%,wasobtained.The elevation of compaction pressure between127-318MPa and blowing agent up to15%(mass fraction)led to anincrease in the linear expansion,compressive strength and densification strain.By varying the foaming temperature from800to1000°C,all of the investigated parameters increased except compressive strength and relative density.The results indicated theoptimal foaming temperature and time as900°C and10-25min,respectively. 展开更多
关键词 aluminum foam powder metallurgy CACO3 foaming agent semi open-cell microstructure EXPANSION compressive properties
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Microstructural evolution and mechanical properties of an ultrahighstrength Al-Zn-Mg-Cu alloy via powder metallurgy and hot extrusion 被引量:8
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作者 CHEN Cun-guang HAN Wei-hao +5 位作者 QI Miao DONG Shi-peng LI Pei YANG Fang HAO Jun-jie GUO Zhi-meng 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第4期1195-1205,共11页
In this work,a novel ultrahigh-strength Al-10Zn-3.5Mg-1.5Cu alloy was fabricated by powder metallurgy followed by hot extrusion.Investigations on microstructural evolution and mechanical properties of the fabricated s... In this work,a novel ultrahigh-strength Al-10Zn-3.5Mg-1.5Cu alloy was fabricated by powder metallurgy followed by hot extrusion.Investigations on microstructural evolution and mechanical properties of the fabricated samples were carried out.The results show that the grain size of sintered samples matches with the powder particles after ball milling.The relative densities of sintered and hot extruded samples reach 99.1%and 100%,respectively.Owing to the comprehensive mechanism of grain refinement,aging and dispersion strengthening,the ultimate tensile strength,yield strength and elongation of the Al-10Zn-3.5Mg-1.5Cu alloy after hot extrusion and subsequent heat treatment achieve 810 MPa,770 MPa and 8%,respectively. 展开更多
关键词 powder metallurgy Al-Zn-Mg-Cu alloy ultrahigh strength hot extrusion
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Process−microstructure−properties relationship in Al−CNTs−Al2O3 nanocomposites manufactured by hybrid powder metallurgy and microwave sintering process 被引量:6
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作者 Meysam TOOZANDEHJANI Farhad OSTOVAN +3 位作者 Khairur Rijal JAMALUDIN Astuty AMRIN Khamirul Amin MATORI Ehsan SHAFIEI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第9期2339-2354,共16页
Al−2CNTs−xAl2O3 nanocomposites were manufactured by a hybrid powder metallurgy and microwave sintering process.The correlation between process-induced microstructural features and the material properties including phy... Al−2CNTs−xAl2O3 nanocomposites were manufactured by a hybrid powder metallurgy and microwave sintering process.The correlation between process-induced microstructural features and the material properties including physical and mechanical properties as well as ultrasonic parameters was measured.It was found that physical properties including densification and physical dimensional changes were closely associated with the morphology and particle size of nanocomposite powders.The maximum density was obtained by extensive particle refinement at milling time longer than 8 h and Al2O3 content of 10 wt.%.Mechanical properties were controlled by Al2O3 content,dispersion of nano reinforcements and grain size.The optimum hardness and strength properties were achieved through incorporation of 10 wt.%Al2O3 and homogenous dispersion of CNTs and Al2O3 nanoparticles(NPs)at 12 h of milling which resulted in the formation of high density of dislocations and extensive grain size refinement.Also both longitudinal and shear velocities and attenuation increase linearly by increasing Al2O3 content and milling time.The variation of ultrasonic velocity and attenuation was attributed to the degree of dispersion of CNTs and Al2O3 and also less inter-particle spacing in the matrix.The larger Al2O3 content and more homogenous dispersion of CNTs and Al2O3 NPs at longer milling time exerted higher velocity and attenuation of ultrasonic wave. 展开更多
关键词 hybrid composite aluminum composites powder metallurgy microwave sintering MICROSTRUCTURE mechanical properties ultrasonic velocity ultrasonic attenuation
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