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Effect of hot extrusion and heat treatment on microstructure of nickel-base superalloy 被引量:17
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作者 刘琛仄 刘锋 +1 位作者 黄岚 江亮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2544-2553,共10页
Effects of hot extrusion (HEX) and heat treatment on prior particle boundary (PPB), MC carbides,γ′precipitates and grain size of nickel-base FGH96 superalloy were studied. The results show that PPB consists of larg... Effects of hot extrusion (HEX) and heat treatment on prior particle boundary (PPB), MC carbides,γ′precipitates and grain size of nickel-base FGH96 superalloy were studied. The results show that PPB consists of largeγ′, MC carbides enriched with Ti, Nb and a modicum of oxides. Thereafter, it can efficaciously tune γ′ precipitate size from micrometer down to nanometer region and simultaneously results in the annihilation of PPB by HEX process. The activation energy for grain growth of as-HEXed FGH96 superalloy was measured to be 402.6 kJ/mol, indicating that γ′ precipitate serves the critical role in inhibiting grain growth under sub-solvus heat treatment. Moreover, the results reveal that grain growth is primarily restrained by MC carbide in the case of super-solvus temperature. 展开更多
关键词 nickel-base superalloy CARBIDE prior particle boundary hot extrusion heat treatment
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Microstructure and mechanical properties of Al-6Zn-2.5Mg-1.8Cu alloy prepared by squeeze casting and solid hot extrusion 被引量:3
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作者 方虹泽 李润霞 +4 位作者 陈瑞润 于宝义 曲迎东 荀诗文 李荣德 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2130-2136,共7页
Al-6Zn-2.5Mg-1.8Cu alloy ingots were prepared by squeeze casting under different specific pressures,and the fresh ingot with best mechanical properties was solid hot extruded.With the increase of the specific pressure... Al-6Zn-2.5Mg-1.8Cu alloy ingots were prepared by squeeze casting under different specific pressures,and the fresh ingot with best mechanical properties was solid hot extruded.With the increase of the specific pressure from 0 to 250 MPa,the dendrites became round and small.Because the applied pressure increased the solid solubility of alloying elements,the number of MgZn2 phases decreased.When the specific pressure increased from 250 MPa to 350 MPa,the grain size increased.After solid hot extrusion,the a(Al) grains were refined obviously and the MgZn2 phases were uniformly dispersed in the microstructure.After solid hot extrusion,the ultimate tensile strength was 605.67 MPa and the elongation was 8.1%,which were improved about 32.22%and15.71%,respectively,compared with those of the metal mold casting alloy.The fracture modes of the billet prepared by the metal mold casting and by squeeze casting were intergranular and quasi-cleavage fractures,respectively,whereas,that of the solid hot extrusion was mainly dimple fracture.The refined crystalline strengthening was the main reason to improve the strength and elongation of alloy. 展开更多
关键词 AlZn alloy squeeze casting solid hot extrusion dynamic recrystallization microstructure 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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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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Microstructure and corrosion behavior of as-cast ADC12 alloy with rare earth Yb addition and hot extrusion 被引量:5
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作者 HE Jia-jia YAN Hong +2 位作者 ZOU Yong-cheng YU Bao-biao HU Zhi 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第6期1654-1665,共12页
The effects of rare earth ytterbium(Yb)addition and hot extrusion on the microstructure and corrosion behavior of as-cast ADC12 were studied by optical microscopy(OM),scanning electron microscopy(SEM),energy dispersiv... The effects of rare earth ytterbium(Yb)addition and hot extrusion on the microstructure and corrosion behavior of as-cast ADC12 were studied by optical microscopy(OM),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS)and X-ray diffraction(XRD).The experimental results demonstrate that both the Si phase andβ-Al5FeSi phase in the alloy with 0.9 wt%Yb have been remarkably refined,and the Al3Yb intermetallic compound has also been obtained.The Si,β-Al5FeSi,and rare earth phases are further refined in the alloy at 0.9 wt%Yb and hot extrusion.The results of the immersion corrosion tests and electrochemical experiments show that the corrosion current density(8.56μA/cm2)of the alloy with 0.9 wt%Yb addition and hot extrusion is 50.6%lower than the untreated alloy(17.33μA/cm2),and the polarization resistance(9252Ω·cm2)was 71.3%higher than the untreated alloy(2654Ω·cm2).The corrosion in the cathode phase in the micro-battery was refined to varying degrees attributable to the addition of Yb and hot extrusion,where the cathode reaction in the corrosion process caused a decrease of the corrosion rate. 展开更多
关键词 ADC12 alloy rare earth Yb addition hot extrusion MICROSTRUCTURE corrosion resistance
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Effects of hot extrusion on microstructure and mechanical properties of Mg matrix composite reinforced with deformable TC4 particles 被引量:8
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作者 Xiaojun Wang Xiaoming Wang +1 位作者 Xiaoshi Hu Kun Wu 《Journal of Magnesium and Alloys》 SCIE 2020年第2期421-430,共10页
Mg matrix composites were often reinforced by non-deformable ceramic particles.In this paper,a novel Mg matrix composite reinforced with deformable TC4(Ti-6Al-4 V)particles was fabricated and then extruded.The evoluti... Mg matrix composites were often reinforced by non-deformable ceramic particles.In this paper,a novel Mg matrix composite reinforced with deformable TC4(Ti-6Al-4 V)particles was fabricated and then extruded.The evolutions of microstructure and mechanical properties of the composite during hot extrusion were investigated.Hoi extrusion refined giains and eliminated the segregation of TC4 particles.TC4 particles,as deformable particles,stimulated the nucleation of dynamic recrystallization during extrusion.However,since the deformation of TC4 particles partly released the stress concentrations around them,the recrystallized grains are just slightly smaller around TC4 particles than that away from them,which is evidently different from the case in Mg matrix composites reinforced by non-deformable ceramic particles.Compared with AZ91 matrix composites reinforced by SiC particles,the present composite possesses the superior comprehensive mechanical properties,which are attributed to not only the strong interfacial bonds between TC4p and matrix but also the deformability of TC4 particles. 展开更多
关键词 Mg matrix composites Ti particles hot extrusion Mechanical properties
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Effect of hot extrusion on microstructure and tribological behavior of Al_(2)O_(3p) reinforced 7075 aluminum-matrix composites 被引量:4
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作者 LEI Yu-shun YAN Hong +4 位作者 WEI Zhi-fan XIONG Jun-jie ZHANG Peng-xiang WAN Jian-ping WANG Zhi-lu 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第8期2269-2284,共16页
The effects of hot extrusion and addition of Al_(2)O_(3p) on both microstructure and tribological behavior of 7075 composites were investigated via optical microscopy(OM),scanning electron microscopy(SEM),energy dispe... The effects of hot extrusion and addition of Al_(2)O_(3p) on both microstructure and tribological behavior of 7075 composites were investigated via optical microscopy(OM),scanning electron microscopy(SEM),energy dispersive spectrometry(EDS),and transmission electron microscopy(TEM).The experimental consequences reveal that the optimal addition of Al_(2)O_(3p) was 2 wt%.After hot extrusion,the Mg(Zn,Cu,Al)2 phases partially dissolve into the matrix and generate many uniformly distributed aging precipitation particles,the Al_(7)Cu_(2)Fe phases are squeezed and broken,and the Al_(2)O_(3p) become uniform distribution.The microhardness of as-extruded 2 wt%Al_(2)O_(3p)/7075 composites reaches HV 170.34,increased by 41.5%than as-cast composites.The wear rate of as-extruded 2 wt%Al_(2)O_(3p)/7075 composites is further lower than that of as-cast composites under the same condition.SEM-EDS analyses reveal that the reinforced wear resistance of composites can put down to the protective effect of the Al_(2)O_(3p) reinforced transition layer.After hot extrusion,the transition layer becomes stable,which determines the reinforced wear resistance of the as-extruded composites. 展开更多
关键词 7075 alloy AL2O3P COMPOSITES hot extrusion MICROSTRUCTURE tribological behavior
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Mechanical properties of Mg-Gd-Zr alloy by Nd addition combined with hot extrusion 被引量:3
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作者 Liu-wei ZHENG Yong-peng ZHUANG +6 位作者 Jun-jian LI Hong-xia WANG Hang LI Hua HOU Li-fei WANG Xiao-ping LUO Kwang Seon SHIN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第6期1866-1880,共15页
The effect of Nd addition on the microstructure and mechanical properties of as-extruded Mg-9Gd-0.5Zr(wt.%) alloy was investigated. The Mg-9Gd-0.5Zr and Mg-9Gd-2Nd-0.5Zr alloys were extruded at 673 K. The elongated no... The effect of Nd addition on the microstructure and mechanical properties of as-extruded Mg-9Gd-0.5Zr(wt.%) alloy was investigated. The Mg-9Gd-0.5Zr and Mg-9Gd-2Nd-0.5Zr alloys were extruded at 673 K. The elongated non-dynamic recrystallized(un-DRXed) grains disappear after adding Nd, and uniformly distributed dynamic recrystallized grains with a grain size of 1.68 μm were obtained in the alloy. In addition, numerous nano-Mg5(Gd,Nd)particles were found to precipitate dynamically in the Mg-9Gd-2Nd-0.5Zr alloy, which gave rise to the dynamic recrystallization process via providing nucleation energy through hindering the release of deformation energy and promoting an increase in the strength through the Orowan strengthening mechanism. Moreover, the dynamically recrystallized(DRXed) grains have a weak texture, which plays a significant role in improving the ductility. Therefore,the Nd addition favors the improvement of strength and elongation for the as-extruded Mg-9Gd-0.5Zr alloy,simultaneously. 展开更多
关键词 Mg-Gd based alloy hot extrusion DRX behavior TEXTURE mechanical properties
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Effect of hot extrusion process on microstructure and mechanical properties of hypereutectic Al-Si alloys 被引量:3
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作者 Li Runxia Yu Fuxiao Zuo Liang 《China Foundry》 SCIE CAS 2011年第1期145-149,共5页
The hypereutectic Al-Si alloy was fabricated by hot extrusion process after solidified under electromagnetic stirring,and the microstructure and mechanical properties of the alloy were studied.The results show that th... The hypereutectic Al-Si alloy was fabricated by hot extrusion process after solidified under electromagnetic stirring,and the microstructure and mechanical properties of the alloy were studied.The results show that the ultimate tensile strength and elongation of the alloy reached 229.5 MPa and 4.6%,respectively with the extrusion ratio of 10,and 263.2 MPa and 5.4%,respectively with extrusion ratio of 20.This indicates that the mechanical properties of the alloy are obviously improved with the increase of extrusion ratio.After hot extruded,the primary Si,eutectic Si,Mg2Si,AlNi,Al7Cu4Ni and Al-Si-Mn-Fe-Cr-Mo phases are refined to different extent,and the efficiency of refinement is obvious more and more with the increase of extrusion ratio.After T6 heat treatment,the sharp corners of these phases become passivated and roundish,and the mechanical properties are improved.The ultimate tensile strength of the extruded alloy after T6 heat treatment reaches 335.3 MPa with extrusion ratio of 10 and 353.6 MPa with extrusion ratio of 20. 展开更多
关键词 hypereutectic Al-Si alloy electromagnetic stirring hot extrusion process primary Si phase
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Effects of Heating and Hot Extrusion Process on Microstructure and Properties of Inconel 625 Alloy 被引量:5
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作者 刘德学 CHENG Xiaowei +1 位作者 ZHANG Xiao DING Yutian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第6期1368-1376,共9页
The effects of the heating process and hot extrusion on the microstructure and properties of inconel 625 alloy were studied. The experimental results showed that the properties of Inconel 625 alloy could be improved t... The effects of the heating process and hot extrusion on the microstructure and properties of inconel 625 alloy were studied. The experimental results showed that the properties of Inconel 625 alloy could be improved through the heating process and hot extrusion concomitant with a reduced corrosion rate. The M23C6 carbide, generated in the heating process, was retained and distributed at the grain boundary during the process of hot extrusion, which had an important influence on both elongation and corrosion resistance. The improvement of the comprehensive properties of the material, as measured by a tensile test at room temperature, was correlated with the dissolution of segregation Nb. A typical ductile fracture changed to a cleavage fracture where secondary cracks could be clearly seen. With the increase of the extrusion ratio, the real extrusion temperature was higher, which led to more dissolution of the M23C6 carbide, decreased the number of secondary cracks, enhanced the effect of solid solution strengthening, and reduced the intergranular corrosion rate. Under the condition of a high extrusion ratio and a high extrusion speed, the less extrusion time made it possible to obtain organization with a smaller average grain size. Moreover, in this case, the M23C6 carbide and segregated Nb did not have enough time to diffuse. Thus all samples exhibited medium strengths and corrosion rates after extrusion. 展开更多
关键词 Inconel 625 alloy hot extrusion mechanical property microstructure evolution
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Effects of the deep rolling process on the surface roughness and properties of an Al-3vol%SiC nanoparticle nanocomposite fabricated by mechanical milling and hot extrusion 被引量:3
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作者 Sajjad Sattari Amir Atrian 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第7期814-825,共12页
Deep rolling is one of the most widely used surface mechanical treatments among several methods used to generate compressive residual stress. This process is usually used for axisymmetric components and can lead to im... Deep rolling is one of the most widely used surface mechanical treatments among several methods used to generate compressive residual stress. This process is usually used for axisymmetric components and can lead to improvements of the surface quality, dimensional accuracy, and mechanical properties. In this study, we deduced the appropriate deep rolling parameters for Al-3vol%Si C nanocomposite samples using roughness and microhardness measurements. The nanocomposite samples were fabricated using a combination of mechanical milling, cold pressing, and hot extrusion techniques. Density measurements indicated acceptable densification of the samples, with no porosity. The results of tensile tests showed that the samples are sufficiently strong for the deep rolling process and also indicated near 50% improvement of tensile strength after incorporating Si C nanoparticle reinforcements. The effects of some important rolling parameters, including the penetration depth, rotation speed, feed rate, and the number of passes, on the surface quality and microhardness were also investigated. The results demonstrated that decreasing the feed rate and increasing the number of passes can lead to greater surface hardness and lower surface roughness. 展开更多
关键词 deep rolling nanocomposite mechanical milling hot extrusion roughness hardness
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Mathematical modeling of induction heating of discard substitution block for billet hot extrusion process 被引量:1
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作者 ZHU Hongda LEI Zuosheng +3 位作者 GUO Jiahong ZHOU Yueming JIN Xiaoli GAO Qi 《Baosteel Technical Research》 CAS 2016年第1期28-32,共5页
A magnetic and temperature field-coupled mathematical model is proposed to calculate the induction heating process of a discard substitution block for billet hot extrusion process. The mathematical model is validated ... A magnetic and temperature field-coupled mathematical model is proposed to calculate the induction heating process of a discard substitution block for billet hot extrusion process. The mathematical model is validated by comparing simulation results with temperature measurements recorded during physical modeling. Based on systematical analysis of calculation results, a quantitative sawtooth induction power curve was proposed to realize the aim of achieving the best distributed temperature field in the block within the shortest induction time. 展开更多
关键词 induction heating discard substitution hot extrusion mathematical modeling
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Forward hot extrusion forming process of 4-lobe aluminum alloy helical surface rotor
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作者 XIA Feng LI Hui +4 位作者 LIU Hou-gen ZHAO Bei-bei ZHANG Zhao-qiang LU Di-hua CHEN Jian-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第9期2307-2317,共11页
The 4-lobe aluminum alloy helical surface rotors are widely applied in industry,such as superchargers.Generally,the conventional manufacturing processes of aluminum alloy helical surface are time consuming and costly.... The 4-lobe aluminum alloy helical surface rotors are widely applied in industry,such as superchargers.Generally,the conventional manufacturing processes of aluminum alloy helical surface are time consuming and costly.To make the manufacturing processes more flexible and economical,the forward hot extrusion process is proposed to form the 4-lobe aluminum alloy helical surface rotors.In this work,we implement both simulations and experiments to the forming process of the helical surface,of which the material is 6063 aluminum alloy.The forward hot extrusion process is simulated with finite element method in DEFORM-3D.Based on the simulation method,the influences of different extrusion parameters,such as extrusion temperature,extrusion speed and extrusion ratio,on the extrusion process are studied.According to the numerical simulation results,the optimal case is chosen to carry out the experiment.Furthermore,the experimental results show that the surface is smooth;the toothed fill is full;the twist angle in the length direction is evenly distributed;the value of twist angle is roughly in line with the design angle,which is mainly due to the modified die structure,having a positive and significant effect on the increment of twist angle.Therefore,the twist angle has an increase of about 76%,which verifies the modified die structure. 展开更多
关键词 6063 aluminum alloy helical surface forward hot extrusion twist angle die structure
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Fabrication of phosphor bronze/Al two-phase material by recycling phosphor bronze chips using hot extrusion process and investigation of their microstructural and mechanical properties
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作者 Majid Hosseini Mohammad Hossein Paydar 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第6期809-817,共9页
Despite the existence of conventional methods for recycling chips,solid-state techniques have become popular,whereby waste metals are directly recycled into consolidated products with the desired shapes and designs.We... Despite the existence of conventional methods for recycling chips,solid-state techniques have become popular,whereby waste metals are directly recycled into consolidated products with the desired shapes and designs.We investigated the feasibility of recycling phosphor bronze chips through a hot extrusion process using aluminum powder as a metal binder for the fabrication of a metal-fiber-reinforced aluminum matrix composite.To do so,mixtures containing 20 vol%–50 vol%of chips were prepared,cold-compacted,and extruded.The quality of the consolidated samples was evaluated by determining the density of the fabricated composites and studying their microstructures.In addition,we performed tensile and hardness tests to evaluate the mechanical properties of the fabricated composites.We also analyzed the fracture surfaces of the samples to study the fracture mechanism as a function of the volume fraction of phosphor bronze chips in the fabricated composite.The results indicated that the most effective consolidation occurred in the sample containing 20 vol%of chips extruded at 465℃in which the chips serve as ideal fibers for improving the mechanical properties,especially the ultimate tensile strength,in comparison with those of Al matrixes that contain no chips but are produced under the same conditions. 展开更多
关键词 RECYCLING hot extrusion metal–metal composite phosphor bronze chips aluminum powder
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Polycrystal modeling of hot extrusion texture of AZ80 magnesium alloy 被引量:4
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作者 邵一川 汤韬 +3 位作者 李大永 周国伟 张少睿 彭颖红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1063-1072,共10页
The visco-plastic self-consistent (VPSC) model is extended to take the dynamical recrystallization (DRX) into account so that the hot extrusion texture of AZ80 magnesium alloy can be properly modeled. The effects of e... The visco-plastic self-consistent (VPSC) model is extended to take the dynamical recrystallization (DRX) into account so that the hot extrusion texture of AZ80 magnesium alloy can be properly modeled. The effects of extrusion temperatures and imposed boundary conditions on the resulting textures were investigated, and good agreement can be found between the simulated and the measured extrusion textures. The simulated results show that the DRX grains are responsible for the formation of the {2110} fiber component since the {1010} poles of the DRX grains are tilted away from those of the unrecrystallized grains during the formation of their high angle boundaries (HABs). Furthermore, the basal poles of the grains are favorably oriented to the transversal direction (TD) where the imposed deformation is larger due to lower slip resistance of the basal slip. The elevated temperature enhances the activity of pyramidal ?c+a? slip modes and gives rise to a larger recrystallized volume fraction, resulting in a weakened extrusion texture. 展开更多
关键词 AZ80 magnesium alloy polycrystal plasticity TEXTURE hot forward extrusion dynamic recrystallization
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Accelerating matrix/boundary precipitations to explore high-strength and high-ductile Co_(34)Cr_(32)Ni_(27)Al_(3.5)Ti_(3.5) multicomponent alloys through hot extrusion and annealing
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作者 Xiaoming Liu Zongde Kou +10 位作者 Ruitao Qu Weidong Song Yijia Gu Changshan Zhou Qingwei Gao Jiyao Zhang Chongde Cao Kaikai Song Vladislav Zadorozhnyy Zequn Zhang Jürgen Eckert 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第12期62-83,共22页
Annealing-regulated precipitation strengthening combined with cold-working is one of the most efficient strategies for resolving the conflict between strength and ductility in metals and alloys.However,precipitation c... Annealing-regulated precipitation strengthening combined with cold-working is one of the most efficient strategies for resolving the conflict between strength and ductility in metals and alloys.However,precipitation control and grain refinement are mutually contradictory due to the excellent phase stability of multicomponent alloys.This work utilizes the high-temperature extrusion and annealing to optimize the microstructures and mechanical properties of the Co_(34)Cr_(32)Ni_(27)Al_(3.5)Ti_(3.5) multicomponent alloy.Hot extrusion effectively reduces grain sizes and simultaneously accelerates the precipitation of coherent L12 nanoparticles inside the face-centered cubic(FCC)matrix and grain boundary precipitations(i.e.,submicron Cr-rich particles and L12-Ni 3(Ti,Al)precipitates),resulting in strongly reciprocal interaction between dislocation slip and hierarchical-scale precipitates.Subsequent annealing regulates grain sizes,dislocations,twins,and precipitates,further allowing to tailor mechanical properties.The high yield strength is attributed to the coupled precipitation strengthening effects from nanoscale coherent L12 particles inside grains and submicron grain boundary precipitates under the support of pre-existing dislocations.The excellent ductility results from the synergistic activation of dislocations,stacking faults,and twins during plastic deformation.The present study provides a promising approach for regulat-ing microstructures,especially defects,and enhancing the mechanical properties of multicomponent alloys. 展开更多
关键词 Multicomponent alloys hot extrusion Microstructure Mechanical properties Precipitation strengthening
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Effect of Hot Extrusion on Interfacial Microstructure and Tensile Properties of SiC_p/2009Al Composites Fabricated at Different Hot Pressing Temperatures 被引量:13
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作者 Peng Jin Bolu Xiao Quanzhao Wang Zongyi Ma Yue Liu Shu Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第6期518-524,共7页
The effects of hot extrusion on the interfacial microstructures and tensile properties of 15 vol.SiCp/2009Al composites fabricated at different hot pressing temperatures were investigated.After hot extrusion,the relat... The effects of hot extrusion on the interfacial microstructures and tensile properties of 15 vol.SiCp/2009Al composites fabricated at different hot pressing temperatures were investigated.After hot extrusion,the relative density of the composites increased,the SiC particle distribution became more uniform,and the SiC particles tended to align along the extrusion direction.Furthermore,the interface bonding was improved after hot extrusion;however,the extrusion exerted no obvious effect on the interfacial reaction products formed during sintering process.Tensile tests indicated that the mechanical properties of the composites were improved significantly after extrusion.Fractography revealed that the fracture mechanism of the extruded composites fabricated at the hot pressing temperatures below 540℃ was mainly the interfacial debonding.For the extruded composites fabricated at 560-600℃,the fracture was the matrix ductile fracture and the SiC particle fracture.When the composites were hot pressed at or above 620℃,after extrusion,the fracture mechanism of the composites was the matrix ductile fracture,the interface cracking and the SiC particle fracture. 展开更多
关键词 Aluminum matrix composite hot extrusion MICROSTRUCTURE Mechanical properties
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Hot Extrusion Process Effect on Mechanical Behavior of Stir Cast Al Based Composites Reinforced with Mechanically Milled B_4C Nanoparticles 被引量:5
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作者 A. Alizadeh E. Taheri-Nassaj M. Hajizamani 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第12期1113-1119,共7页
In this study, aluminum alloy (Al-2 wt% Cu) matrix composites reinforced with I, 2 and 4 wt% boron carbide nanoparticles fabricated through mechanical milling with average size of 100 nm were fabricated via stir cas... In this study, aluminum alloy (Al-2 wt% Cu) matrix composites reinforced with I, 2 and 4 wt% boron carbide nanoparticles fabricated through mechanical milling with average size of 100 nm were fabricated via stir casting method at 850℃. Cast ingots of the matrix alloy and the composites were extruded at 500℃ at an extrusion ratio of 10:1 to investigate the effects of hot extrusion on the mechanical properties of the composites. The microstructures of the as-cast and the extruded composites were investigated by scanning electron microscopy (SEM). Density measurement, hardness and tensile tests were carried out to identify the mechanical properties of the composites. The extruded samples revealed a more uniform distribution of B4C nanoparticles. Also, the extruded samples had strength and ductility values superior to those of the as-cast counterparts. In the as-cast and the extruded samples, with increasing amount of B4C nanoparticles, yield strength and tensile strength increased but e^ongation to fracture decreased. 展开更多
关键词 Stir casting hot extrusion Al matrix composite B4C nanoparticles Mechanicalmilling
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Effect of Si Content on Dynamic Recrystallization of Al-Si-Mg Alloys During Hot Extrusion 被引量:4
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作者 Yuna Wu Hengcheng Liao +1 位作者 Jian Yang Kexin Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2014年第12期1271-1277,共7页
By using electron backscatter diffraction(EBSD) and transmission electron microscopy(TEM), the effect of Si content on microstructure characteristics of three as-extruded Ale SieM g alloys was investigated. Result... By using electron backscatter diffraction(EBSD) and transmission electron microscopy(TEM), the effect of Si content on microstructure characteristics of three as-extruded Ale SieM g alloys was investigated. Results showed that the density of coarse Si particles played a critical role in dynamic recrystallization. Dynamic recrystallization rarely occurred in S1 alloy with less Si content; however, it happened in the Si-rich zones in S2 alloy with a medium Si content. And a mature recrystallization was observed in S3 alloy with high Si content. Although deformation was carried out at high temperature, particle-stimulated dynamic recrystallization occurred in Si-rich zones. 展开更多
关键词 Al-Si-Mg alloys Electron backscatter diffraction(EBSD) Transmission electron microscopy(TEM) Dynamic recrystallization hot extrusion
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Microstructural evolution of spray-formed Al-11.5Zn-2.0Mg-1.6Cu alloy during hot-extrusion and heat-treatment 被引量:3
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作者 GUO Shu NING Zhi-liang +1 位作者 CAO Fu-yang SUN Jian-fei 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2009年第S02期343-348,共6页
Al-11.5Zn-2.0Mg-1.6Cu alloy was synthesized by spray forming(SF)technique followed by hot extrusion and heat-treatment.Its microstructural evolution was investigated by scanning electron microscopy(SEM),transmission e... Al-11.5Zn-2.0Mg-1.6Cu alloy was synthesized by spray forming(SF)technique followed by hot extrusion and heat-treatment.Its microstructural evolution was investigated by scanning electron microscopy(SEM),transmission electron microscopy(TEM)with energy dispersive spectroscopy(EDS)and X-ray diffraction(XRD)in the whole process.The curve of hardness as a function of aging time was obtained at 120℃.Test results indicate that the grain morphology is equiaxed and uniform in the central region of the spray-formed billet,but fine and irregular in the bottom and top regions.Both the grain boundary and the intragranular phases are identified as MgZn_(2) intermetallics.Hot extrusion promotes the refinement of the microstructure.Grain boundary phase disappears,meanwhile,η-phase(MgZn_(2))and Al_(3)Zr particles precipitate from the matrix after extrusion.The alloy reaches its maximum hardness after being aged at 120℃for 14 h,associated with a massive precipitation of intermediateη′-phase (MgZn)in the matrix. 展开更多
关键词 Al-Zn-Mg-Cu alloy spray forming microstructure hot extrusion aging
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