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Effect of the capsule on deformation and densification behavior of nickel-based superalloy compact during hot isostatic pressing 被引量:3
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作者 Lebiao Yang Xiaona Ren +4 位作者 Chao Cai Pengju Xue MIrfan Hussain Yusheng Shi Changchun Ge 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第1期122-130,共9页
The Shima yield criterion used in finite element analysis for nickel-based superalloy powder compact during hot isostatic pressing(HIP) was modified through uniaxial compression experiments. The influence of cylindric... The Shima yield criterion used in finite element analysis for nickel-based superalloy powder compact during hot isostatic pressing(HIP) was modified through uniaxial compression experiments. The influence of cylindrical capsule characteristics on FGH4096M superalloy powder compact deformation and densification behavior during HIP was investigated through simulations and experiments. Results revealed the simulation shrinkage prediction fitted well with the experimental shrinkage including a maximum shrinkage error of 1.5%. It was shown that the axial shrinkage was 1.7% higher than radial shrinkage for a cylindrical capsule with the size of ∮50 mm × 100 mm due to the force arm difference along the axial and radial direction of the capsule. The stress deviated from the isostatic state in the capsule led to the uneven shrinkage and non-uniform densification of the powder compact. The ratio of the maximum radial displacement to axial displacement increased from0.47 to 0.75 with the capsule thickness increasing from 2 to 4 mm. The pressure transmission is related to the capsule thickness, the capsule material performance, and physical parameters in the HIP process. 展开更多
关键词 hot isostatic pressing nickel-based superalloy compact CAPSULE DENSIFICATION deformATION
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Pressure generation under deformation in a large-volume press
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作者 Saisai Wang Xinyu Zhao +8 位作者 Kuo Hu Bingtao Feng Xuyuan Hou Yiming Zhang Shucheng Liu Yuchen Shang Zhaodong Liu Mingguang Yao Bingbing Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期622-626,共5页
Deformation can change the transition pathway of materials under high pressure,thus significantly affects physical and chemical properties of matters.However,accurate pressure calibration under deformation is challeng... Deformation can change the transition pathway of materials under high pressure,thus significantly affects physical and chemical properties of matters.However,accurate pressure calibration under deformation is challenging and thereby causes relatively large pressure uncertainties in deformation experiments,resulting in the synthesis of complex multiphase materials.Here,pressure generations of three types of deformation assemblies were well calibrated in a Walker-type largevolume press(LVP)by electrical resistance measurements combined with finite element simulations(FESs).Hard Al_(2)O_(3) or diamond pistons in shear and uniaxial deformation assemblies significantly increase the efficiency of pressure generation compared with the conventional quasi-hydrostatic assembly.The uniaxial deformation assembly using flat diamond pistons possesses the highest efficiency in these deformation assemblies.This finding is further confirmed by stress distribution analysis based on FESs.With this deformation assembly,we found shear can effectively promote the transformation of C60 into diamond under high pressure and realized the synthesis of phase-pure diamond at relatively moderate pressure and temperature conditions.The present developed techniques will help improve pressure efficiencies in LVP and explore the new physical and chemical properties of materials under deformation in both science and technology. 展开更多
关键词 shear/uniaxial deformation pressure calibration finite element simulations large-volume press high pressure
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Simple shear extrusion versus equal channel angular pressing:A comparative study on the microstructure and mechanical properties of an Mg alloy 被引量:2
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作者 A.Rezaei R.Mahmudi +1 位作者 C.Cayron R.E.Logé 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第5期1769-1790,共22页
Two severe plastic deformation(SPD)techniques of simple shear extrusion(SSE)and equal channel angular pressing(ECAP)were employed to process an extruded Mg-6Gd-3Y-1.5Ag(wt%)alloy at 553 K for 1,2,4 and 6 passes.The mi... Two severe plastic deformation(SPD)techniques of simple shear extrusion(SSE)and equal channel angular pressing(ECAP)were employed to process an extruded Mg-6Gd-3Y-1.5Ag(wt%)alloy at 553 K for 1,2,4 and 6 passes.The microstructural evolutions were studied by electron back scattered diffraction(EBSD)analysis and transmission electron microscopy(TEM).The initial grain size of 7.5μm in the extruded alloy was reduced to about 1.3μm after 6 SPD passes.Discontinuous dynamic recrystallization was suggested to be operative in both SSE and ECAP,with also a potential contribution of continuous dynamic recrystallization at the early stages of deformation.The difference in the shear strain paths of the two SPD techniques caused different progression rate of dynamic recrystallization(DRX),so that the alloys processed by ECAP exhibited higher fractions of recrystallization and high angle grain boundaries(HAGBs).It was revealed that crystallographic texture was also significantly influenced by the difference in the strain paths of the two SPD methods,where dissimilar basal plane texture components were obtained.The compression tests,performed along extrusion direction(ED),indicated that the compressive yield stress(CYS)and ultimate compressive strength(UCS)of the alloys after both SEE and ECAP augmented continuously by increasing the number of passes.ECAP-processed alloys had lower values of CYS and UCS compared to their counterparts processed by SSE.This difference in the mechanical responses was attributed to the different configurations of basal planes with respect to the loading direction(ED)of each SPD technique. 展开更多
关键词 Mg-Gd-Y alloys Severe plastic deformation Simple shear extrusion Equal channel angular pressing Dynamic recrystallization Mechanical properties
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Influence of hot isostatic pressing on microstructure,properties and deformability of selective laser melting TC4 alloy 被引量:3
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作者 Tai-qi Yan Bing-qing Chen +1 位作者 Xia Ji Shao-qing Guo 《China Foundry》 SCIE CAS 2021年第4期389-396,共8页
The influence of different hot isostatic pressing regimes on microstructure,phase constitution,microhardness,tensile properties and deformability of TC4 alloy fabricated by selective laser melting(SLM)technology was s... The influence of different hot isostatic pressing regimes on microstructure,phase constitution,microhardness,tensile properties and deformability of TC4 alloy fabricated by selective laser melting(SLM)technology was studied.The results show that the microstructure of SLM TC4 alloy is composed of acicular martensiteα’phase,and the sample exhibits high microhardness and strength,but low plasticity.After hot isostatic pressing,acicular martensiteα’phase transforms intoα+βphase,and with the increase of hot isostatic pressing temperature and duration,αphase with coarse lath is gradually refined,and the proportion ofαphase is gradually reduced.Because of the change of phase constitution in SLM TC4 alloy after hot isostatic pressing,the grain refinement strengthening is weakened,the density of dislocation is reduced,so that both microhardness and tensile strength are decreased by around 20%,the elongation is increased by more than about 70%,even over 100%,compared with as-deposited TC4 alloy.When the hot isostatic pressing regime is 940°C/3 h/150 MPa,the tensile strength and the elongation achieve optimal match,which are about890 MPa and around 14.0%in both directions.The fracture mechanism of alloy after 940 oC/3 h/150 MPa HIP is dultile fracture.Hot isostatic pressing causes concave deformation of SLM TC4 alloy thin-walled frames,and the deformation degree increases with the increase of temperature. 展开更多
关键词 selective laser melting TC4 alloy hot isostatic pressing MICROSTRUCTURE mechanical properties deformABILITY
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Deformed texture of copper processed by equal channel angular pressing via different angle routes 被引量:2
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作者 武保林 黄震威 +2 位作者 张宇东 宝磊 C. ESLING 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第3期479-485,共7页
The commercially pure copper with dimension of 80 mm×20 mm×4 mm was used for equal channel angular pressing (ECAP), of which their outward appearance coordinate is corresponded with that of rolling deformati... The commercially pure copper with dimension of 80 mm×20 mm×4 mm was used for equal channel angular pressing (ECAP), of which their outward appearance coordinate is corresponded with that of rolling deformation modes. Cold-deformed texture was investigated. The results show that the texture character in pure copper processed by ECAP is related with intersection angle (Φ) of the die channel. When Φ is 90° and the sample is extruded for one pass, its texture consists of α and β orientation lines including mainly C, B, S and Goss components, moreover a little rotated cube is found. When Φ is 135°, as extrusion pass increases, the weak texture forms on the scope of deviation from rotated cube (ψ=0°, θ=0°,φ=450°±150°) and develops to the ψ=45° fiber mainly including rotated cube. When Φ is 120°, the texture is ψ=45° fiber mainly including rotated cube that is maintained constant as extrusion pass increases. 展开更多
关键词 压制方法 组织结构 变形性能
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Deformation mechanism at impact test of Al-11% Si alloy processed by equal-channel angular pressing with rotary die 被引量:2
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作者 马爱斌 Y. NISHIDA +3 位作者 江静华 N. SAITO I. SHIGEMATSU A. WATAZU 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第1期104-109,共6页
Al-11%Si(mass fraction)alloy was transformed into a ductile material by equal-channel angular pressing(ECAP)with a rotary die.Two mechanisms at impact test,slip deformation by dislocation motion and grain boundary sli... Al-11%Si(mass fraction)alloy was transformed into a ductile material by equal-channel angular pressing(ECAP)with a rotary die.Two mechanisms at impact test,slip deformation by dislocation motion and grain boundary sliding,were discussed.The ultrafine grains with modified grain boundaries and the high content of fine particles(<1μm)were necessary for attaining high absorbed energy.The results contradict the condition of slip deformation by dislocation motion and coincide with that of grain boundary sliding.Many fine zigzag lines like a mosaic were observed on the side surface of the tested specimens.These observed lines may show grain boundaries appeared by the sliding of grains. 展开更多
关键词 铝合金 变形行为 微观结构 晶界滑动
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HOT PRESSING AND ITS DEFORMATION MECHANISM OF Ag-SHEATHED DPSCCO SUPERCONDUCTING TAPES
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作者 Ma, Yanwei Wang, Xianjin Wang, Zutang 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第1期89-92,共4页
HOTPRESSINGANDITSDEFORMATIONMECHANISMOFAgSHEATHEDDPSCCOSUPERCONDUCTINGTAPES①MaYanwei,WangXianjinandWangZuta... HOTPRESSINGANDITSDEFORMATIONMECHANISMOFAgSHEATHEDDPSCCOSUPERCONDUCTINGTAPES①MaYanwei,WangXianjinandWangZutangDepartmentofMe... 展开更多
关键词 Ag-sheathed SUPERCONDUCTING TAPES HOT pressing deformation mechanismcritical current density
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OBSERVATION OF DISLOCATION CONFIGURATIONS IN AGED & DEFORMED NiAl ALLOY AFTER HOT ISOSTATIC PRESSING (HIP)
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作者 Cui Yuexian Dong Shangli +3 位作者 Liu Bo Li Daoming Yang Dezhuang(Schwa of Materials Sccience and Engineering, Harbin instituteOf Technology, Harbin, China, 150001 )Bi Geping Wang Qin(Central iron and Steel Research institute, Beijing China, 100081 ) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第4期278-283,共6页
Observation of dislocation configurations was conducted for aged and compressive deformed (Ni64A136) FeMoB alloy after hot isostatic pressing (HIP). It isshown that short and straight parallel dislocations are present... Observation of dislocation configurations was conducted for aged and compressive deformed (Ni64A136) FeMoB alloy after hot isostatic pressing (HIP). It isshown that short and straight parallel dislocations are present in the matrix of NiAI alloy.Long and tortuous dislocations and superdislocations appear in the 1%-deformed specimen. As the compressive strain increases to 2. 6%, high-densities dislocations appear inand between the deformation bands. The dislocations become tangled up in the specimencompressed to a strain of 6. 2 %. 展开更多
关键词 NIAL hot isostatic press compressive deformation dislocations(materials) aging (metallurgy)
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Deformation Behavior and Microstructure Evolution during Equal Channel Angular Pressing of Pure Aluminum
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作者 XU Shubo WANG Hanlin +2 位作者 LIU Peng JING Cainian REN Guocheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第1期130-135,共6页
The deformation behavior of equal channel angular pressing(ECAP)was discussed by using plasticity method.The node mapping method is employed to realize the analysis of multi-pass ECAP by using three-dimensional FEM me... The deformation behavior of equal channel angular pressing(ECAP)was discussed by using plasticity method.The node mapping method is employed to realize the analysis of multi-pass ECAP by using three-dimensional FEM methods for pure aluminum.The single-pass ECAP is a non-uniform shear deformation process in the cross-section of the workpiece.The uniform deformation processing routes are obtained during multi-pass ECAP process.In addition,the density of dislocations and defects of crystal lattice are also largely changed for different processing routes.The grain microstructure is gradually refined with the increase of the pressing passes.The grains and their distribution obtained by route Bc are more useful for producing the material with high angle grain boundaries.The grain microstructure of the cross section of the pressed material decreases with the increase of strain,and some grains exhibit transformed grain boundary(PTB)fringes.The dislocation density in the grain decreases,and the grain boundary presents equiaxed distribution. 展开更多
关键词 severe plastic deformation equal channel angular pressing/extrusion finite element analysis pure aluminum MICROSTRUCTURE
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Strain rate-dependent high temperature compressive deformation characteristics of ultrafine-grained pure aluminum produced by ECAP 被引量:1
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作者 颜莹 齐跃 +1 位作者 陈立佳 李小武 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期966-973,共8页
To explore the effect of strain rate ε on the high temperature deformation characteristics of ultrafine-grained materials, the deformation and damage features as well as microstructures of ECAP-treated pure Al at dif... To explore the effect of strain rate ε on the high temperature deformation characteristics of ultrafine-grained materials, the deformation and damage features as well as microstructures of ECAP-treated pure Al at different temperatures T and strain ratesε were systematically studied through compression tests and microscopic observations. The increase in ε eliminates strain softening at T≤473 K, and largely enhances the yield strength and flow stress at 473?573 K. The shear deformation dominates the plastic deformation of ECAP-treated Al. Many cracks along shear bands (SBs) are formed at T≥473 K and secondary SBs basically disappear at 1×10?3 s?1; however, at 1×10?2 s?1, cracks are only observed at temperature below 473 K, and secondary SBs become clearer at T≥473 K. The microstructures of ECAP-treated Al mainly consist of sub-grains (SGs). The increase in ε inhibits the SG growth, thus leading to the increases both in yield strength and flow stress at high temperatures. 展开更多
关键词 equal channel angular pressing(ECAP) pure Al strain rate high temperature compression deformATION damage microstructure
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Microstructure evolution of a recycled Al-Fe-Si-Cu alloy processed by tube channel pressing 被引量:3
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作者 M.H.Farshidi M.Rifai H.Miyamoto 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第10期1166-1172,共7页
Although excellent recyclability is one of the advantages of Al alloys, a recycling process can reduce different properties of these alloys by adding coarse AlFeSi particles into the alloys' microstructures. One o... Although excellent recyclability is one of the advantages of Al alloys, a recycling process can reduce different properties of these alloys by adding coarse AlFeSi particles into the alloys' microstructures. One of the well-known methods for modifying the microstructure of metallic materials is the imposition of severe plastic deformation(SPD). Nevertheless, the microstructure evolutions of recycled Al alloys containing extraordinary fractions of AlFeSi particles during SPD processing have seldom been considered. The aim of the present work is to study the microstructure evolution of a recycled Al–Fe–Si–Cu alloy during SPD processing. For this purpose, tubular specimens of the mentioned alloy were subjected to different numbers of passes of a recently developed SPD process called tube channel pressing(TCP); their microstructures were then studied using different techniques. The results show that coarse AlFeSi particles are fragmented into finer particles after processing by TCP. However, decomposition and dissolution of AlFeSi particles through TCP processing are negligible. In addition, TCP processing results in an increase in hardness of the alloy, which is attributed to the refinement of grains, to an increase of the dislocation density, and to the fragmentation of AlFeSi particles. 展开更多
关键词 AlFeSi INTERMETALLIC particle severe plastic deformation microstructure TUBE CHANNEL pressing
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Deformation behavior and microstructural evolution during hot compression of an a+b Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy 被引量:1
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作者 Gao-feng Liu Shang-zhou Zhang +1 位作者 Li-qing Chen Jian-xun Qiu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第3期344-351,共8页
The effect of processing parameters on the flow response and microstructural evolution of the a+b titanium alloy Ti-6.5Al-3.5Mo-1.5Zr-0.3Si has been studied by conducting isothermal hot compressive tests at a strain ... The effect of processing parameters on the flow response and microstructural evolution of the a+b titanium alloy Ti-6.5Al-3.5Mo-1.5Zr-0.3Si has been studied by conducting isothermal hot compressive tests at a strain rate of 0.01-10 s-1 at 860-1100°C. The true stress-true strain curves of the sample hot-compressed in the a+b phase region exhibit a peak stress followed by continuous flow softening, whereas in the b region, the flow stress attains a steady-state regime. At a strain rate of 10 s-1, the alloy exhibits plastic flow insta-bilities. According to the kinetic rate equation, the apparent activation energies are estimated to be about 674-705 kJ/mol in the a+b region and 308-335 kJ/mol in the b region, respectively. When deformed in the a+b region, the globularization process of the a colony structure occurs, and a dynamic recrystallized microstructures are observed to show bimodal. Dynamic recrystallization can take place in the b region irrespective of starting deformed structures. 展开更多
关键词 titanium alloys hot pressing deformation microstructural evolution activation energy
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The precipitation behavior of MgZn_(2) and Mg_(4)Zn_(7) phase in Mg-6Zn(wt.%)alloy during equal-channel angular pressing 被引量:4
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作者 Kai Yan Jing Bai +1 位作者 Huan Liu Zhao-Yang Jin 《Journal of Magnesium and Alloys》 SCIE EI CAS 2017年第3期336-339,共4页
As-extruded Mg-6Zn(wt.%)Alloy was subjected to severe plastic deformation(SPD)by the equal-channel angular pressing(ECAP)at 160 ℃.The results of tensile tests at room temperature showed that two passes ECAP resulted ... As-extruded Mg-6Zn(wt.%)Alloy was subjected to severe plastic deformation(SPD)by the equal-channel angular pressing(ECAP)at 160 ℃.The results of tensile tests at room temperature showed that two passes ECAP resulted in a remarkable improvement of strength,yield strength from 200 to 265 MPa and ultimate tensile strength from 260 to 340 MPa.However,with the deformation increasing,the samples processed by ECAP for four or six passes had insignificant difference than that processed by two-pass ECAP.Massive precipitates were observed in all the Mg-6Zn alloys specimens processed by ECAP.Transmission electron microscope and X-ray diffraction results indicated that ECAP treatment induced the precipitation of laves MgZn_(2) phase and transition Mg_(4)Zn_(7) phase.The spherical MgZn_(2) particles and irregular shape Mg_(4)Zn_(7) particles coexist in the microstructure of Mg-6Zn alloy after six pass ECAP. 展开更多
关键词 Mg-Zn alloy Equal-channel angular pressing(ECAP) MgZn_(2) Mg_(4)Zn_(7) deformation induced precipitation
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Finite Element Analysis of the Groove Pressing of Aluminum Alloy
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作者 Mehdi Shaban Ghazani Akbar Vajd 《Modeling and Numerical Simulation of Material Science》 2014年第1期32-36,共5页
In this paper, the finite element method was applied to analyze the deformation behavior of Al-1%Mg alloy during constrained groove pressing (CGP). Deformation inhomogeneity was studied in term of plastic strain distr... In this paper, the finite element method was applied to analyze the deformation behavior of Al-1%Mg alloy during constrained groove pressing (CGP). Deformation inhomogeneity was studied in term of plastic strain distribution during deformation. It was found that after first pressing and flattening steps, the plastic strain is inhomogeneous but second pressing and flattening improve deformation distribution considerably. Also the regions between flat and inclined parts of sample receive less shear strain and consequently after four passes the deformation distribution is still inhomogeneous and doesn’t improve remarkably with more deformation steps. 展开更多
关键词 FINITE Element Simulation CONSTRAINED GROOVE pressing deformation INHOMOGENEITY
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Equal-Channel Angular Pressing as a New Processing to Control the Microstructure and Texture of Metallic Sheets
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作者 Tong Xiao Hiroyuki Miyamoto Toshiyuki Uenoya 《Materials Sciences and Applications》 2012年第9期600-605,共6页
The extended band structures of as-cold-rolled high Cr steel sheets are recrystallisation-resistant, and tend to become aggregates of the so-called grain colonies as a partially recovered state after final annealing. ... The extended band structures of as-cold-rolled high Cr steel sheets are recrystallisation-resistant, and tend to become aggregates of the so-called grain colonies as a partially recovered state after final annealing. Such band structures diminish formability and become origin of the so-called ridging. A novel processing will be shown here, which involves strain-path change by introducing one-pass ECAP prior to cold-rolling, and facilitates recrystallisation. Indeed, the recrystallisation temperature was reduced by 100℃, compared with cold-rolling alone imposing an equivalent strain. Grain- scale microshear bands introduced during one-pass ECAP perturbed the banded structures in post-ECAP cold-rolling and enhanced the recrystallisation at the final annealing. 展开更多
关键词 SEVERE Plastic deformation Equal-Channel ANGULAR pressing (ECAP) RECRYSTALLISATION Texture Ferritic STAINLESS Steel Strain Path
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AZ31镁合金和7050铝合金ECAP过程的数值模拟研究
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作者 刘毅 薛凤梅 +1 位作者 墨馨遥 王廖子 《热加工工艺》 北大核心 2024年第9期73-79,83,共8页
利用Abaqus有限元软件分别对AZ31镁合金和7050铝合金进行等通道转角挤压(ECAP)数值模拟研究。利用有限元(FE)模拟得到应力场、应变场及载荷-位移曲线,分析了在不同挤压温度、挤压速度、摩擦条件和不同截面下等通道转角挤压的变形规律。... 利用Abaqus有限元软件分别对AZ31镁合金和7050铝合金进行等通道转角挤压(ECAP)数值模拟研究。利用有限元(FE)模拟得到应力场、应变场及载荷-位移曲线,分析了在不同挤压温度、挤压速度、摩擦条件和不同截面下等通道转角挤压的变形规律。结果表明,挤压温度升高可以降低挤压载荷,这有利于AZ31镁合金挤压,在摩擦较小情况下进行变形有利于降低挤压载荷,提高变形均匀性;在不考虑变形过程中温升效应的情况下,挤压速度对挤压载荷影响较小,当挤压速度提高时,最大等效应变值有所提高;圆形截面比方形截面更适合进行等通道转角挤压。 展开更多
关键词 等通道转角挤压(ECAP) 大塑性变形(SPD) 数值模拟 AZ31镁合金 7050铝合金
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重型锻造液压机理论设计与实际变形对比研究分析
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作者 杨莎 王鹏 王鑫 《锻压装备与制造技术》 2024年第2期18-25,共8页
重型锻造液压机的精度是保证制件精度的一个重要指标,而设备机架的刚度指标是横梁设备整个精度保持性的一个标准。本文利用ANSYS有限元分析软件对重型锻造液压机的框架变形情况进行了分析,并与现场实际测量的变形值进行了对比研究。通... 重型锻造液压机的精度是保证制件精度的一个重要指标,而设备机架的刚度指标是横梁设备整个精度保持性的一个标准。本文利用ANSYS有限元分析软件对重型锻造液压机的框架变形情况进行了分析,并与现场实际测量的变形值进行了对比研究。通过对比,得出数据差值,为后续同类型设备的刚度设计提供相应的设计依据。 展开更多
关键词 重型锻造液压机 刚度 有限元分析 变形
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高阶变性Pascal蜗线齿轮生成机制分析 被引量:1
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作者 陶德华 李凝 +2 位作者 宣仲义 王笑 郑丽娟 《西华大学学报(自然科学版)》 CAS 2024年第3期45-53,共9页
为满足多样性变速传动的设计要求,文章在研究Pascal蜗线非圆节曲线的基础上,通过引入高阶和变性原理,建立了高阶变性Pascal蜗线型非圆齿轮节曲线数学模型及其凹凸性判别公式。为分析高阶变性Pascal蜗线型非圆齿轮传动特性,利用MATLAB编... 为满足多样性变速传动的设计要求,文章在研究Pascal蜗线非圆节曲线的基础上,通过引入高阶和变性原理,建立了高阶变性Pascal蜗线型非圆齿轮节曲线数学模型及其凹凸性判别公式。为分析高阶变性Pascal蜗线型非圆齿轮传动特性,利用MATLAB编写可视化设计分析平台,对影响高阶变性Pascal蜗线型非圆齿轮形状和传动特性的因素进行分析,为后续高阶变性Pascal蜗线型非圆齿轮的设计及应用提供了便捷的设计参考;将Pascal蜗线非圆齿轮驱动的曲柄滑块式压力机与对心曲柄滑块式压力机进行对比分析,验证了Pascal蜗线型非圆齿轮的优势和在实际应用中的可行性。 展开更多
关键词 Pascal蜗线齿轮 高阶齿轮 变性齿轮 传动比 压力机
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Aging behavior and mechanical properties of 6013 aluminum alloy processed by severe plastic deformation 被引量:8
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作者 刘满平 蒋婷慧 +5 位作者 王俊 刘强 吴振杰 Ying-da YU Pl C.SKARET Hans J.ROVEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3858-3865,共8页
Structural features, aging behavior, precipitation kinetics and mechanical properties of a 6013 Al–Mg–Si aluminum alloy subjected to equal channel angular pressing (ECAP) at different temperatures were comparative... Structural features, aging behavior, precipitation kinetics and mechanical properties of a 6013 Al–Mg–Si aluminum alloy subjected to equal channel angular pressing (ECAP) at different temperatures were comparatively investigated with that in conventional static aging by quantitative X-ray diffraction (XRD) measurements, differential scanning calorimetry (DSC) and tensile tests. Average grain sizes measured by XRD are in the range of 66-112 nm while the average dislocation density is in the range of 1.20×10^14-1.70×10^14 m^-2 in the deformed alloy. The DSC analysis reveals that the precipitation kinetics in the deformed alloy is much faster as compared with the peak-aged sample due to the smaller grains and higher dislocation density developed after ECAP. Both the yield strength (YS) and ultimate tensile strength (UTS) are dramatically increased in all the ECAP samples as compared with the undeformed counterparts. The maximum strength appears in the samples ECAP treated at room temperature and the maximum YS is about 1.6 times that of the statically peak-aged sample. The very high strength in the ECAP alloy is suggested to be related to the grain size strengthening and dislocation strengthening, as well as the precipitation strengthening contributing from the dynamic precipitation during ECAP. 展开更多
关键词 Al-Mg-Si aluminum alloy severe plastic deformation equal-channel angular pressing aging behavior precipitation kinetics mechanical properties strengthening mechanisms
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压合衬套二次冷挤压强化数值仿真与实验研究
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作者 刘儒军 黄翔 +3 位作者 黄海鸿 陶梅生 殷超超 班许可岭 《机械科学与技术》 CSCD 北大核心 2024年第7期1142-1150,共9页
采用压合衬套二次冷挤压工艺对7050铝合金耳片孔进行挤压强化;通过X射线衍射仪、三坐标测量机和粗糙度仪,研究二次冷挤压对耳片孔内表面的残余应力、塑性变形以及粗糙度的影响,并通过有限元仿真进行验证。实验结果表明:相较于一次冷挤压... 采用压合衬套二次冷挤压工艺对7050铝合金耳片孔进行挤压强化;通过X射线衍射仪、三坐标测量机和粗糙度仪,研究二次冷挤压对耳片孔内表面的残余应力、塑性变形以及粗糙度的影响,并通过有限元仿真进行验证。实验结果表明:相较于一次冷挤压,压合衬套二次冷挤压可有效改善试样两端残余应力的不均匀性。随着二次冷挤压相对挤压量增大,残余压应力峰值和应力层深度都进一步增大,塑性变形程度也更大,同时降低了孔壁表面粗糙度。在相对挤压量为2.5%时,最大残余压应力可达-400.3 MPa,并形成了约14 mm的残余压应力层;试样端面A与端面B内径分别增大了0.56 mm和0.54 mm;孔壁表面粗糙度降低幅度达到71.0%。相较于一次冷挤压,二次冷挤压强化后孔壁沿径向形成了更深的残余压应力层和塑性变形层,显著提高了耳片孔的整体服役性能。 展开更多
关键词 二次冷挤压 压合衬套 相对挤压量 残余应力 塑性变形
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