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Chinese Physics B 2021年第5期30卷 520-525页

作者： Qi-Xin Xiao Zhao-Yang Hou Chang Li Yuan Niu School of Science Chang'an UniversityXi'an 710064China

The mechanical property and deformation mechanism of twinned gold nanowire with non-uniform distribution of twinned boundaries(TBs)are studied by the molecular dynamics(MD)*** is found that the twin boundary spacing(TBS)has a great effect on the strength and plasticity of the nanowires with uniform distribution of *** the strength enhances with the decrease of TBS,while its plasticity *** the nanowires with non-uniform distribution of TBs,the differences in distribution among different TBSs have little effect on the Young's modulus or strength,and the compromise in strength *** the differences have a remarkable effect on the plasticity of twinned gold *** twinned gold nanowire with higher local symmetry ratio has better *** initial dislocations always form in the largest TBS and the fracture always appears at or near the twin boundaries adjacent to the smallest *** simulation results are consistent with the experimental results.

关键词： twin nanowire gold non-uniform distribution mechanical property molecular dynamics simulation

mechanical property and cellular structure of an additive manufactured FeCoNiCrMo_(0.2) high-entropy alloy at high-velocity deformation

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Journal of Materials Science & Technology 2023年第8期139卷 156-166页

作者： Wenshu Li YiYu Huang ZhongHao Xie Haoyu Chen Weihua Li Bin Liu Bingfeng Wang State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China

The microstructural modification for cellular structures can achieve the improvement of dynamic me-chanical properties of a selective laser melted FeCoNiCrMo_(0.2)high-entropy alloy(SLM-FeCoNiCrMo_(0.2)HEA)and can expand its promising applications in the field of high-velocity *** this work,FeCoNiCrMo_(0.2)HEAs with cellular structures in different sizes were produced by selective laser melt-ing(SLM)with different process *** dynamic mechanical properties and microstructure of the SLM-FeCoNiCrMo_(0.2)HEA were *** dynamic mechanical properties of the SLM-FeCoNiCrMo_(0.2)HEA increased with decrease of average size of cellular structures,and the values of them were sensitive to strain *** energy absorption,compressive strength and yield strength of the SLM-FeCoNiCrMo_(0.2)HEAs reached 315.6 MJ/m^(3),2.2 GPa and 775.6 MPa,respectively at a strain rate of 2,420 s^(−1),under the process parameters of laser power and scanning speed of 330 W and 800 mm/s,respectively,where the corresponding average size of cellular structures in the HEAs was 483.6 *** value of strain-hardening rate of the SLM-FeCoNiCrMo_(0.2)HEA was about 5.1 GPa at a strain level of 0.1,which was much higher than that of the powder-metallurgy FeCoNiCrMo_(0.2)*** cellular structure was formed inside the molten pool with segregation of Mo on the *** localization appeared in the cellular structures,forming several deformation bands after high strain-rate *** elemental segre-gation strengthening and dislocation strengthening are considered to be the main strengthening mecha-nisms in SLM-FeCoNiCrMo_(0.2)HEA.

关键词： FeNiCr-based HEA Additive manufacturing mechanical property Cellular structure Strengthening mechanisms

mechanical property and Microstructure of Cement Mortar with Carbonated Recycled Powder

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 689-697页

作者：丁亚红张美香 YANG Xiaolin XU Ping SUN Bo GUO Shuqi Department of Civil Engineering Henan Polytechnic UniversityJiaozuo 454150China College of Architectural Engineering Xinyu UniversityXinyu 336500China

Carbonated recycled powder as cementitious auxiliary material can reduce carbon emissions and realize high-quality recycling of recycled *** this paper,microscopic property of recycled powder with three carbonation methods was tested through XRD and SEM,the mechanical property and microstructure of recycled powder mortar with three replacement rates were studied by ISO method and SEM,and the strengthening mechanism was *** results showed that the mechanical property of recycled powder mortar decreased with the increasing of replacement *** is suggested that the replacement rate of recycled powder should not exceed 20%.The strength index and activity index of carbonated recycled powder mortar were improved,in which the flexural strength was increased by 27.85%and compressive strength was increased by 20%at the *** powder can be quickly and completely carbonated,and the improvement effect of CH pre-soaking carbonation was the *** activity index of carbonated recycled powder can meet the requirements of Grade II technical standard for recycled *** results revealed the activation mechanism of carbonated recycled powder such as surplus calcium source effect,alkaline polycondensation effect and carbonation enhancement effect.

关键词： recycled powder carbonation activation compound carbonation activity index mechanical property microstructure

mechanical property and Microstructural Characterization of C-Mn-Al-Si Hot Dip Galvanizing TRIP Steel

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Journal of Iron and Steel Research International 2012年第8期19卷 29-36页

作者： JIANG Hai-tao1, DING Wei1,2, TANG Di1, HUANG Wei1 (1. National Engineering Research Center for Advanced Rolling Technology, University of Science and Technology Beijing, Beijing 100083, China 2. School of Material and Metallurgy, Inner Mongolia University of Science and Technology, Baotou 014010, Inner Mongolia, China) [a] National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China [b] School of Material and Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 Inner Mongolia China

mechanical properties and microstructure in high strength hot dip galvanizing TRIP steel were investigated by optical microscope (OM), transmission electron microscope (TEM), X-ray diffraction (XRD), dilatometry and mechanical testing. On the heat treatment process of different intercritical annealing (IA) temperatures, isothermal bainitic transformation (IBT) temperatures and IBT time, this steel shows excellent mechanical properties with tensile strength over 780 MPa and elongation more than 22%. IBT time is a crucial factor in determining the mechanical properties as it confirms the bainite transformation process, as well as the microstructure of the steel. The microstructure of the hot dip galvanizing TRIP steel consisted of ferrite, bainite, retained austenite and martensite during the short IBT time. The contents of ferrite, bainite, retained austenite and martensite with different IBT time were calculated. The results showed that when IBT time increased from 20 to 60 s, the volume of bainite increased from 14.31% to 16.95% and the volume of retained austenite increased from 13.64% to 16.28%; meanwhile, the volume of martensite decreased from 7.18% to 1.89%. Both the transformation induced plasticity of retained austenite and the hardening of martensite are effective, especially, the latter plays a dominant role in the steel containing 7.18% martensite which shows similar strength characteristics as dual-phase steel, but a better elongation. When martensite volume decreases to 1.89%, the steel shows typical mechanical properties of TRIP, as so small amount of martensite has no obvious effect on the mechanical properties.

关键词： TRIP steel isothermal bainitic transformation martensite mechanical property

mechanical property and irradiation damage of China Low Activation Martensitic(CLAM) steel

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Science China(Physics,Mechanics & Astronomy) 2012年第11期55卷 2057-2061页

作者： ZHU YanYong WAN FaRong GAO Jin HAN WenTuo HUANG YiNa JIANG ShaoNing QIAO JianSheng ZHAO Fei YANG ShanWu OHNUKI Somei HASHIMOTO Naoyuki Department of Materials Physics and Chemistry University of Science and Technology BeijingBeijing 100083China Central Iron and Steel Research Institute Beijing 100081China Department of Engineering Physics University of WisconsinWI53706USA China Institute of Atomic Energy Beijing 102413China Department of Material Physics Guizhou UniversityGuiyang 550025China Faculty of Engineering Hokkaido UniversitySapporo 060JapanDepartment of Material PhysicsGuizhou UniversityGuiyang 550025China

China Low Activation Martensitic （CLAM） steel is being studied to develop the structural materials for a fusion reactor, which has been designed based on the well-known 9Crl.5WVTa steel. The effect of tempering temperature on hardness and micro- structure of CLAM steel was studied. The strength of CLAM steel increased by adding silicon, and the ductility remained con- stant. Conversely, while CLAM steel maintained good ductility with the addition of yttrium, its tensile strengths were greatly degraded. Behaviors under electron irradiation of CLAM steel were examined using the high voltage electron microscope. Electron irradiation at 450℃ formed many voids in CLAM steel with basic composition, whereas CLAM with silicon steel did not change the microstructure significantly.

关键词： low activation ferritic/martensitic steel mechanical property electron irradiation irradiation damage silicon yttrium

mechanical property of Low Chromium Semi-Steel Grinding Ball Prepared by Cross Rolling

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Journal of Iron and Steel Research International 2004年第5期11卷 50-54页

作者： CHANGLi-min MENGDe-liang NIEPu-lin LIUJian-hua JilinNormalUniversity Siping136000China YanshanUniversity Qinhuangdao066004China

The preparing method,rolling technology and mechanical properties of low chromium semi-steel grinding ball by cross rolling were *** results show that when the low chromium semi-steel bar is forged from55mm to50mm,cross-rolled into grinding ball at 1 000-1 050℃,air cooled and tempered at 550℃for 2h,the best mechanical properties,especially the abrasive resistance under the action of hard abrasive,can be obtained.

关键词： low chromium semi-steel grinding ball cross rolling mechanical property

mechanical property and permeability of raw coal containing methane under unloading confining pressure

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International Journal of Mining Science and Technology 2013年第6期23卷 789-793页

作者： Yin Guangzhi Li Wenpu Jiang Changbao Li Minghui Li Xing Liu Hairu Zhang Qiangui State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University College of Resources and Environmental Sciences Chongqing University State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam School of Petroleum Engineering Southwest Petroleum University

Based on domestic-developed triaxial servo-controlled seepage equipment for thermal-hydrologicalmechanical coupling of coal containing methane,an experimental study was carried out to investigate mechanical property and gas permeability of raw coal,under the situation of conventional triaxial compression and unloading confining pressure tests in different gas pressure *** unloading confining pressure process was reducing confining pressure while increasing axial *** research results show that,compared with the peak intensity of conventional triaxial loading,the ultimate strength of coal samples of triaxial unloading confining pressure was lower,deformation under loading was far less than unloading,dilation caused by unloading was more obvious than *** change trend of volumetric strain would embody change of gas permeability of coal,the permeability first reduced along with volumetric strain increase,and then raised with volume strain decrease,furthermore,the change trends of permeability of coal before and after destruction were different in the stage of decreasing volume strain due to the effect of gas *** gas pressure was greater,the effective confining pressure was smaller,and the radial deformation produced by unloading was *** the unloading failed confining pressure difference was smaller,coal would be easier to get unstable failure.

关键词： Mining engineering Unloading confining pressure Coal containing methane mechanical property Permeability

Microstructure and mechanical property of NbTaTiV refractory high-entropy alloy with different Y_(2)O_(3) contents

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Rare Metals 2022年第10期41卷 3504-3514页

作者： Tao Liao Yuan-Kui Cao Wen-Min Guo Qi-Hong Fang Jia Li Bin Liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha410082China

In this study,NbTaTiV refractory high-entropy alloys(RHEAs) reinforced with dispersed oxides were successfully designed and fabricated by mechanical alloying and subsequent spark plasma sintering(SPS).The effects of Y_(2)O_(3) content on the microstructure and mechanical properties have been systematically *** results show that the oxide dispersion strengthening(ODS) RHEAs are mainly composed of body centered cubic(BCC) matrix and multiscale oxides,including submicron Ti-(N,O) particles,nano-sized Y-Ti-O particles and nano-sized Y_(2)O_(3) *** ODS-RHEAs have excellent mechanical properties due to the multisc ale *** the content of Y_(2)O_(3) increasing from 1 wt% to 3 wt% Y_(2)O_(3),the compressive yield strength of the ODSRHEAs significantly increases from 1528 to 1866 MPa,while the fracture strain slightly reduces from 22% to 16%.The enhancement of the mechanical property is mainly attributed to the increased amount of multisc ale oxide particles and the refined grain structure.

关键词： Refractory high-entropy alloy Oxide dispersion strengthening Spark plasma sintering(SPS) mechanical property Strengthening mechanism

Effect of HEA/Al composite interlayer on microstructure and mechanical property of Ti/Mg bimetal composite by solid-liquid compound casting

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China Foundry 2023年第1期20卷 1-11页

作者： Jin Cheng Jian-hua Zhao Chun Wang Jing-jing Shangguan Cheng Gu Ya-jun Wang College of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China Beijing Power Machinery Research Institute Beijing 100074China

In this study,HEA/AI composite interlayer was used to fabricate Ti/Mg bimetal composites by solidliquid compound casting *** Al layer was prepared on the surface of TC4 alloy by hot dipping,and the FeCoNiCr HEA layer was prepared by magnetron sputtering onto the Al *** influence of the HEA layer thickness and pouring temperature on interface evolution was investigated based on SEM observation and thermodynamic *** indicate that the sluggish diffusion effect of HEA can effectively inhibit the interfacial diffusion between Al and Mg,which is conducive to the formation of solid solution,especially when the thickness of HEA is 800 *** the increase of casting temperature from 720 ℃ to 730 ℃,740℃,and 750 ℃,α-Al(Mg),α-Al(Mg)+Al3Mg2,Al3Mg2+Al12Mg17,and Al12Mg17+δ-Mg are formed at the interface of Ti/Mg bimetal,*** the thickness of the HEA layer is 800 nm and the pouring temperature is 720 ℃,the bonding strength of the Ti/Mg bimetal can reach the maximum of 93.6 MPa.

关键词： Ti/Mg bimetal composite microstructure solid-liquid compound casting HEA/Al composite interlayer mechanical property

Corrosion behavior and mechanical property of Mg-4Li-1Ca alloys under micro-compressive stress

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Journal of Materials Science & Technology 2024年第8期175卷 170-184页

作者： Yuanyuan Wang Chengbao Liu Zuojun Jiao Lei Cai Cong Sun Deming Wang Lanyue Cui Cuie Wen Rong-Chang Zeng Corrosion Laboratory for Light Metals School of Materials Science and EngineeringShandong University of Science and TechnologyQingdao 266590China School of Engineering RMIT UniversityMelbourneVIC 3001Australia

Biomedical materials may suffer from stress-induced corrosion when performing as implant materials at load-bearing sites, bringing about variations in the microstructure, corrosion resistance, and mechanical properties. In this study, the corrosion behavior and mechanical properties of an extruded Mg-4Li-1Ca alloy were investigated under different micro-compressive stresses (0-6 MPa) using a novel homemade loading device. Under 0-3 MPa of micro-compressive stress, the strong basal texture of extruded Mg-4Li1Ca alloys was weakened and the internal stress gradient stimulated grain boundary migration to induce grain growth. Meanwhile, increased stress resulted in the precipitation of second-phase particles and the accumulation of residual stress, accelerating the corrosion rate due to preferential corrosion. However, with increasing stress, the volume fraction of the second phase increased, becoming the dominant factor controlling the corrosion rate, and residual stress was released for samples under 4.5-6 MPa of microcompressive stress. Hence, surface corrosion product films rapidly formed and served as effective physical barriers, weakening the microstructural effect on the corrosion behavior. The yield strength of Mg-4Li-1Ca alloy reached 95.48 MPa under 3 MPa of micro-compressive stress owing to the dual effects of precipitation strengthening and shear-band strengthening. The relationships between microstructure, corrosion behavior, and mechanical property provide a theoretical foundation for understanding the degradation characteristics of the Mg-4Li-1Ca alloy under physiological loading and practical application.

关键词： Magnesium alloy Biomaterial Compressive stress Texture Corrosion mechanical property