Accommodation processes during deformation of nanocrystalline palladium
Accommodation processes during deformation of nanocrystalline palladium
复制标题
DOI：
10.1016/j.actamat.2010.06.026
复制
发表时间：
2010-09
期刊：
影响因子：
9.4
通讯作者：
D. Bachurin;P. Gumbsch
中科院分区：
文献类型：
--
作者：
D. Bachurin;P. Gumbsch
在室温和不同应变速率下对三维纳米晶钯的单轴拉伸和压缩应变进行了原子模拟。详细分析表明，初始塑性变形是由于晶粒内部局部弯曲所适应的晶界滑动和位错胚的形成所致。在拉伸应变的后期发现没有位错活动的晶间裂纹。在压缩应变过程中，样品表现出塑性响应，这主要是由晶间调节过程引起的。发现从晶界发射的扩展部分位错以及变形后期阶段的完全位错和孪晶对总应变的贡献是微不足道的。
Atomistic simulations of uniaxial tensile and compressive straining of three-dimensional nanocrystalline palladium were performed at room temperature and different strain rates. Detailed analysis revealed that initial plastic deformation is due to grain boundary sliding accommodated by localized bending inside the grains and the formation of dislocation embryos. Intergranular cracking in the absence of dislocation activity was found at later stages of tensile straining. During compressive straining the sample shows a plastic response which is brought about mainly by intergranular accommodation processes. The contribution of extended partial dislocations emitted from the grain boundaries as well as full dislocations and twinning at later stages of deformation to the total strain was found to be insignificant.