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论凯尔森纯粹法理论之宪法效力观 被引量:2
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作者 张云铎 《成都理工大学学报(社会科学版)》 2016年第4期1-6,共6页
我国《宪法》具有最高法律效力,其特征体现在普适性、程序严格、不得相抵触三个方面,据此可引出三个问题,即宪法为何应被遵守?为什么宪法的制定和修改程序较普通法律更为严格?法律抵触宪法无效?凭借独创的"纯粹法理论"在宪法... 我国《宪法》具有最高法律效力,其特征体现在普适性、程序严格、不得相抵触三个方面,据此可引出三个问题,即宪法为何应被遵守?为什么宪法的制定和修改程序较普通法律更为严格?法律抵触宪法无效?凭借独创的"纯粹法理论"在宪法学领域作出不可湮磨贡献的凯尔森,他对上述问题的回答是:宪法应当被遵守是因为其效力来源于"基础规范";程序更严格是对"实质宪法"的形式化的要求;"法律抵触宪法无效"是一个没有意义的陈述。以上解答便代表了凯尔森对宪法效力问题的核心观点,即其纯粹法理论下的宪法效力观,希望籍此能将纯粹法理论的合理内核融入当今宪法学理论研究之中,使"规范性"得到更多的重视。 展开更多
关键词 最高效力 凯尔森 纯粹法理论 宪法效力观 规范性
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简析奥斯丁的法律效力观
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作者 冯立坡 刘晶 《法制与经济》 2009年第16期75-76,78,共3页
奥斯丁将独立政治社会中至高无上的主权者作为法律效力的来源,认为法律之所以对其指向的对象产生约束力,或者说法律指向的对象之所以遵守法律,是因为"主权"、"命令"和"制裁"中所直接或间接所说明的强制... 奥斯丁将独立政治社会中至高无上的主权者作为法律效力的来源,认为法律之所以对其指向的对象产生约束力,或者说法律指向的对象之所以遵守法律,是因为"主权"、"命令"和"制裁"中所直接或间接所说明的强制力的缘故。这种被称之为"恶法亦法"的法律效力观,从产生之日起,人们就对其褒贬不一。 展开更多
关键词 奥斯丁 法律 效力观
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法律效力的经验证成 被引量:2
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作者 刘婵秀 《法律科学》 CSSCI 北大核心 2001年第1期57-64,共8页
从法律效力的直接对象———理性人出发 ,在将法律效力与法律实效进行区别的基础上重新对其进行审视 :法律效力应是一个过程 ,它并不仅仅基于立法而止 ,良好的法律实效因为得到了人们的认可也可以成为法律效力的一个来源。同法律效力的... 从法律效力的直接对象———理性人出发 ,在将法律效力与法律实效进行区别的基础上重新对其进行审视 :法律效力应是一个过程 ,它并不仅仅基于立法而止 ,良好的法律实效因为得到了人们的认可也可以成为法律效力的一个来源。同法律效力的逻辑探寻不同 ,这种效力力源的发现乃是一种经验求证 ,而在现代社会 ,它才是真正的法治软件。 展开更多
关键词 法律效力 法律实效 经验效力 经验力 事实效力观
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Characteristic and optimization of ferrite-rich sulfoaluminate-based composite cement suitable for cold region tunnels
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作者 PENG You LI Li +5 位作者 TAN Xian-jun QIU Xin ZHENG Pei-chao XIE Jun CHEN Wei-zhong REZIWANGULI Sha-ta-er 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2794-2809,共16页
To develop suitable grouting materials for water conveyance tunnels in cold regions,firstly,this study investigated the performance evolution of ferrite-rich sulfoaluminate-based composite cement(FSAC grouting materia... To develop suitable grouting materials for water conveyance tunnels in cold regions,firstly,this study investigated the performance evolution of ferrite-rich sulfoaluminate-based composite cement(FSAC grouting material)at 20 and 3℃.The results show that low temperature only delays the strength development of FSAC grouting material within the first 3 d.Then,the effect of four typical early strength synergists on the early properties of FSAC grouting material was evaluated to optimize the early(£1 d)strength at 3℃.The most effective synergist,Ca(HCOO)_(2),which enhances the low-temperature early strength without compromising fluidity was selected based on strength and fluidity tests.Its micro-mechanism was analyzed by XRD,TG,and SEM methods.The results reveal that the most suitable dosage range is 0.3 wt%−0.5 wt%.Proper addition of Ca(HCOO)_(2)changed the crystal morphology of the hydration products,decreased the pore size and formed more compact hydration products by interlocking and overlapping.However,excessive addition of Ca(HCOO)_(2)inhibited the hydration reaction,resulting in a simple and loose structure of the hydration products.The research results have reference value for controlling surrounding rock deformation and preventing water and mud inrushes during the excavation in cold region tunnels. 展开更多
关键词 ferrite-rich sulfoaluminate cement cold zone early strength synergist mechanical property MICRO-STRUCTURE pumped storage power
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Influence of aging on microstructure and mechanical properties of AZ80 and ZK60 magnesium alloys 被引量:13
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作者 李艳 张治民 薛勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期739-744,共6页
The effect of aging on the microstructure and mechanical properties of AZ80 and ZK60 wrought magnesium alloys was studied with optical microscope and mechanical testers. The results demonstrate that both the tensile s... The effect of aging on the microstructure and mechanical properties of AZ80 and ZK60 wrought magnesium alloys was studied with optical microscope and mechanical testers. The results demonstrate that both the tensile strength and elongation of AZ80 alloy increase firstly and then decrease as the aging temperature rises, the peak values appear when the aging temperature is 170 ℃ The hardness of ZK60 alloy increases firstly and then decreases as the aging temperature rises, and the hardness reaches its peak value at 170 ℃. However, the toughness of the alloy is just the opposite. Moreover, ZK60 alloy has good performances in both impact toughness and other mechanical properties at the aging temperature from 140 ℃ to 200 ℃. 展开更多
关键词 AZ80 magnesium alloy ZK60 magnesium alloy AGING MICROSTRUCTURE mechanical properties
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Effects of process parameters on mechanical properties and microstructures of creep aged 2124 aluminum alloy 被引量:7
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作者 湛利华 李炎光 黄明辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2232-2238,共7页
A series of tests were carried microstructures of 2124 aluminum alloy in increase of aging time, temperature and low-to-peak-to-low manner. No significant out to investigate the effects of process parameters on mechan... A series of tests were carried microstructures of 2124 aluminum alloy in increase of aging time, temperature and low-to-peak-to-low manner. No significant out to investigate the effects of process parameters on mechanical properties and creep aging process. The results show that creep strain and creep rate increase with the applied stress. The hardness of specimen varies with aging time and stress in a effect of temperature on hardness of material is seen in the range of 185-195 ℃. The optimum mechanical properties are obtained at the conditions of (200 MPa, 185 ℃, 8 h) as the result of the coexistence of strengthening S" and S' phases in the matrix by transmission electron microscopy (TEM). TEM observation shows that applied stress promotes the formation and growth of precioitates and no obvious stress orientation effect is observed in the matrix. 展开更多
关键词 aluminum alloy creep aging behavior age hardening mechanical property MICROSTRUCTURE process parameter
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Microstructure and mechanical properties of extruded Mg-8.5Gd-2.3Y-1.8Ag-0.4Zr alloy 被引量:1
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作者 周浩 王渠东 +2 位作者 陈杰 叶兵 郭炜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第8期1891-1895,共5页
The microstructure, age hardening behavior and mechanical properties of an Mg-8.5Gd-2.3Y-1.8Ag-0.4Zr alloy prepared by casting and hot extrusion techniques were investigated. The solution-treated (T4 temper) alloys ... The microstructure, age hardening behavior and mechanical properties of an Mg-8.5Gd-2.3Y-1.8Ag-0.4Zr alloy prepared by casting and hot extrusion techniques were investigated. The solution-treated (T4 temper) alloys were extruded at 400, 450 and 500 °C with an extrusion ratio of 10:1, respectively. Optimized mechanical properties were obtained by extrusion at 400 °C followed by T5 treatment under the combined effects of grain refinement and precipitation strengthening. The alloy exhibits a grain size of about 5.0 μm, initial and peak microhardness of HV 109 and HV 129, respectively. The tensile yield strength, ultimate tensile strength and elongation at room temperature are 391 MPa, 430 MPa and 5.2%, respectively. 展开更多
关键词 Mg-Gd-Y-Ag-Zr alloy EXTRUSION age hardening microstructure mechanical property
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Effective Moduli of Two-Layered Spherical Inclusions Reinforced Composites
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作者 胡更开 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期59-66,共8页
A model is proposed to evaluate the,effective modufi of a composite reinforced by two-layered spherical inclusions.This model is based on the localisation problem of a two- layered spherical inclusion embedded in an i... A model is proposed to evaluate the,effective modufi of a composite reinforced by two-layered spherical inclusions.This model is based on the localisation problem of a two- layered spherical inclusion embedded in an infinite matrix.The interations of the reinforced phases are taken into account by using the average matrix stress concept.When the external layer vanishes,the proposed model reduces to the classical Mori-Tanaka's model for spherical inclusions.Theoretical results for the composite of polyester matrix filled by hollow glass spheres and voids show excellent agreement with experimental results. 展开更多
关键词 two-layered spherical inclusion effective moduli COMPOSITE MICROMECHANICS
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Influence of temperature on creep behavior,mechanical properties and microstructural evolution of an Al-Cu-Li alloy during creep age forming 被引量:2
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作者 ZHOU Chang ZHAN Li-hua +2 位作者 LI He ZHAO Xing HUANG Ming-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第8期2285-2294,共10页
The effect of temperature in range of 155-175 ℃ on the creep behavior, microstructural evolution, and precipitation of an Al-Cu-Li alloy was experimentally investigated during creep ageing deformation under 180 MPa f... The effect of temperature in range of 155-175 ℃ on the creep behavior, microstructural evolution, and precipitation of an Al-Cu-Li alloy was experimentally investigated during creep ageing deformation under 180 MPa for 20 h. Increasing temperature resulted in a noteworthy change in creep ageing behaviour, including a variation in creep curves, an improvement in creep rate during early creep ageing, and an increased creep strain. Tensile tests indicate that the specimen aged at higher temperature reached peak strength within a shorter time. Transmission electron microscopy(TEM) was employed to explore the effect of temperature on the microstructural evolution of the AA2198 during creep ageing deformation. Many larger dislocations and even tangled dislocation structures were observed in the sample aged at higher temperature. The number of T1 precipitates increased at higher ageing temperature at the same ageing time. Based on the analysed results, a new mechanism, considering the combined effects of the formation of larger dislocation structures induced by higher temperature and diffusion of solute atoms towards these larger or tangled dislocations, was proposed to explain the effect of temperature on microstructural evolution and creep behaviour. 展开更多
关键词 Al-Cu-Li alloys creep age forming mechanical properties MICROSTRUCTURE PRECIPITATION
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Effect of Li addition on mechanical properties and ageing precipitation behavior of extruded Al-3.0 Mg-0.5 Si alloy 被引量:3
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作者 YANG Xiao-kun XIONG Bai-qing +6 位作者 LI Xi-wu YAN Li-zhen LI Zhi-hui ZHANG Yong-an LI Ya-nan WEN Kai LIU Hong-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第9期2636-2646,共11页
The effect of Li(2.0 wt%)addition on mechanical properties and ageing precipitation behavior of Al-3.0 Mg 0.5 Si was investigated by tensile test,dynamic elasticity modulus test,scanning electron microscopy(SEM),trans... The effect of Li(2.0 wt%)addition on mechanical properties and ageing precipitation behavior of Al-3.0 Mg 0.5 Si was investigated by tensile test,dynamic elasticity modulus test,scanning electron microscopy(SEM),transmission electron microscopy(TEM)and high-resolution transmission electron microscopy(HRTEM)images.The results show that the tensile strength of the Li-containing alloy can be significantly improved;however,the ductility is sharply decreased and the fracture mechanism changes from ductile fracture to intergranular fracture.The elasticity modulus of the Li-containing alloy increases by 11.6%compared with the base alloy.The microstructure observation shows that the Li addition can absolutely change the precipitation behavior of the base alloy,andδ′-Al_(3)Li phase becomes the main precipitates.Besides,β′′-Mg_(2)Si andδ′-Al_(3)Li dual phases precipitation can be visibly observed at 170℃ ageing for 100 h,although the quantity ofδ′-Al_(3)Li phase is more thanβ′′-Mg_(2)Si phase.The width of the precipitate-free zone(PFZ)of the Li-containing alloy is much wider at the over-ageing state than the base alloy,which has a negative impact on the ductile and results in the decrease of elongation. 展开更多
关键词 Al-3.0 Mg-0.5 Si alloy Li addition microstructure ageing behavior mechanical properties dynamic elasticity modulus
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Effects of interrupted ageing and asymmetric rolling on microstructures, mechanical properties, and intergranular corrosion behavior of Al-Mg-Si-Zn alloy 被引量:2
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作者 TIAN Ai-qin XU Xue-hong +1 位作者 SUN Lin DENG Yun-lai 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第3期821-835,共15页
Effects of interrupted ageing(T6I6) and asymmetric rolling on microstructures, mechanical properties, and intergranular corrosion(IGC) behaviors of Al-Mg-Si-Zn alloy were investigated. Results showed that the T6 alloy... Effects of interrupted ageing(T6I6) and asymmetric rolling on microstructures, mechanical properties, and intergranular corrosion(IGC) behaviors of Al-Mg-Si-Zn alloy were investigated. Results showed that the T6 alloy has the lowest strength and the worst IGC resistance, while the T6I6 alloy has higher strength and better IGC resistance.What’ s more, the alloy treated by pre-rolling deformation has higher strength and better IGC resistance;and the alloy treated by the pre-asymmetry rolling achieves the highest strength, the best IGC resistance and lower elongation. The mechanical properties depend on microstructures such as the grain size, texture, dislocation density and precipitation, the grain boundary misorientation and grain boundary microstructure are responsible for the IGC resistance. 展开更多
关键词 Al-Mg-Si-Zn alloy interrupted ageing asymmetric rolling microstructure mechanical property intergranular corrosion property
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Observe the efficacy of the air wave pressure therapeutic equipment in treatment of oxaliplatin nerve toxicity
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作者 Weihua Qian Yingying Pan Yimin Yang 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第10期602-604,共3页
Objective: The aim of this study was to observe the efficacy of air wave pressure therapeutic equipment in pre- vention of oxaliplatin-inducted neurotoxicity. Methods: Forty-five patients with colorectal cancer were... Objective: The aim of this study was to observe the efficacy of air wave pressure therapeutic equipment in pre- vention of oxaliplatin-inducted neurotoxicity. Methods: Forty-five patients with colorectal cancer were randomly divided into treatment group and control group, treatment group were given the treatment of air wave pressure therapeutic equipment during chemotherapy with oxaliplatin, the control group were given preventive treatment, the oxaliplatin-inducted neurotoxicity was evaluated after each cycle of chemotherapy. Evaluate the chemotherapy efficacy after the third cycle and sixth cycle of chemotherapy. Results: The treatment group have lower incidence of peripheral nerve toxicity than the control group, the difference was statistically significant (X2= 13.93; P 〈 0.01). Chemotherapy effect between the 2 groups was no significant difference (P 〉 0.05). Conclusion: Treatment with air wave pressure therapeutic equipment can reduce the incidence of peripheral nerve toxicity during oxaliplatin chemotherapy. 展开更多
关键词 CHEMOTHERAPY OXALIPLATIN NEUROTOXICITY colorectal cancer
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Application Study on Correction Method for Lag of Water Level Response to Earth Tide and Atmospheric Pressure
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作者 Geng Jie You Benyue Zhang Zhaodong 《Earthquake Research in China》 2006年第2期225-231,共7页
The water level in a deep well instantly responds to the earth’s tide and atmospheric pressure, and varies accordingly, not only in terms of amplitude but also in the phase lag. Therefore, phase lag correction is use... The water level in a deep well instantly responds to the earth’s tide and atmospheric pressure, and varies accordingly, not only in terms of amplitude but also in the phase lag. Therefore, phase lag correction is used in analyzing digital groundwater observation data in eastern China. Calculation results presented by the authors in this paper show that the correction method is effective in the identification of anomalous changes for short-term seismic precursors. The correction method can also be applied to the processing of observed deformation and tilt data. 展开更多
关键词 Earth tide Atmospheric pressure Lag effect Short-term anomaly METHOD
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Sustaining the Gains of Change: Lessons for Organizational Leadership 被引量:1
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作者 Xolani Ngonini Ola Busari 《Management Studies》 2017年第6期606-620,共15页
With the aim of drawing valuable lessons for the management and planning of similar business transformation initiatives, this paper critically evaluates a change project at an organization in South Africa, from three ... With the aim of drawing valuable lessons for the management and planning of similar business transformation initiatives, this paper critically evaluates a change project at an organization in South Africa, from three inter-woven dimensions: creating the climate for change, engaging and enabling the organization, and sustaining change. Firstly, a key achievement demonstrates that attempts to create a conducive climate for change should recognize that the unit of change in any organization is, ultimately, the individual. Levers for such initiatives should navigate the macro-organizational change narrative and translate change generalities into specific individual actions and behaviors. Secondly, learning from an implementation gap, similar efforts would gain better traction in engagement and empowerment by leveraging on an influential cross-functional team made up of enthusiastic supporters of the required change, to foster ownership and to embrace change across the organization. Key characteristics that should be represented on the team include leadership skills, expertise, credibility, effective communication, and a sense of urgency. Thirdly, in terms of sustaining change, twin lessons surge to the fore. On a positive note, by progressing its values-set into an annual staff award, there is a pointer to the potential of innovatively encouraging and rewarding employees to live the value qualities. And, on the flip side, a need is underscore of the critical role of seamless executive leadership, providing ongoing co-creating windows for instilling positive attitudes and creating synergies among related strategic initiatives. 展开更多
关键词 organizational leadership South Africa sustaining change TCTA
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Investigation on Fuzzy in English Literature Teaching
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作者 Li Jian Yao Kunming 《International Journal of Technology Management》 2013年第3期62-65,共4页
This thesis studies the concept and research background of filzziness and fuzzy theory, then committing further enumeration and analysis of the application of fuzzy theory in the fields of linguistics and literature. ... This thesis studies the concept and research background of filzziness and fuzzy theory, then committing further enumeration and analysis of the application of fuzzy theory in the fields of linguistics and literature. On this basis, the effectiveness and rationalization of the fuzzy theory's application in the English literature teaching were confirmed from many aspects. Among them, it is mainly investigated and analyzed from the objective factors and subjective factors. Subjective aspects mainly contain students' different cognitive ability, and the diversity existed in teachers' teaching and guiding methods. Objective aspects mainly include that the literature language and literature thoughts itself have the unique ambiguity. Finally, in summing up the investigation results the author put forward the essence of English literature teaching activity and put forward the methods to improve English literature teaching. 展开更多
关键词 English literature teaching fuzzy theory low carbon education
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Thickness effects on magnetoelectric coupling for Metglas/PZT/Metglas laminates 被引量:3
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作者 FANG Fei ZHAO ChangPeng YANG Wei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第4期581-585,共5页
Thickness effects on the ME coefficient αME and electromechanical resonance frequency of Metglas/PZT/Metglas tri-layered laminates are investigated. The thickness of the magnetic plate is changed by assembling differ... Thickness effects on the ME coefficient αME and electromechanical resonance frequency of Metglas/PZT/Metglas tri-layered laminates are investigated. The thickness of the magnetic plate is changed by assembling different numbers of the Metglas thin sheets (30μm for each layer) while the PZT plate is maintained at constant thickness (0.5 mm). At 1 kHz of the applied alter- nating magnetic field, only one peak presents in the ME coefficient (OCME) versus static magnetic field (Hs) curve. As the thickness ratio n increases, the peak value of αME first increases and reaches a maximum at approximately n = 0.519, and then decreases afterward. The peak position (Hoptim) moves steadily toward a higher value as n increases. It is suggested that the re- laxation factor k of the magnetic phase is reduced as n increases, causing the decrease of the piezomagnetic coefficient d11,m and the increase of Hoptim. By employing the micromechanics model and considering the degradation of dll,m with n, an opti- mized thickness ratio of 0.5 is predicted, which is in agreement with the experimental observations. The resonance frequency of the laminate increases with n, which is consistent with the calculation using a straightforward mixture law. 展开更多
关键词 magnetoelectric behavior layered composite PZT Metgals multiferroic materials
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Molecular dynamics study on the nano-void growth and coalescence at grain boundary 被引量:5
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作者 LIN EnQiang NIU LiSha +1 位作者 SHI HuiJi DUAN Zheng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第1期86-93,共8页
Molecular dynamics simulations using embedded atom method (EAM) potential were performed to study nano-void growth and coalescence at grain boundary in face-centered cubic bicrystal copper. Thin-plate specimens subjec... Molecular dynamics simulations using embedded atom method (EAM) potential were performed to study nano-void growth and coalescence at grain boundary in face-centered cubic bicrystal copper. Thin-plate specimens subjected to uniaxial tension strain with one-void and two-void at the centered grain boundary were employed to analyze the effect of specimen size, temperature and applied strain rate on the stress-strain response, incipient yield strength and macroscopic effective Young's modulus. The evolutions of dislocations, twin bands and void shapes under different specimen sizes were also presented. The obtained results show that, regardless of the void numbers, the specimen sizes, temperature, the applied strain rate had significant influence on the void shape evolution, stress-strain curve and incipient yield strength, while negligible effects on the macroscopic effective Young's modulus except for the temperature. Moreover, the voids growth rate along the grain boundary was also found to be associated with the specimen sizes. 展开更多
关键词 BICRYSTAL void growth void coalescence grain boundary molecular dynamics simulations embedded atom method
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