
个人信息Personal Information
性别:男
学科:力学. 航空宇航科学与技术. 材料科学与工程. 机械工程. 冶金工程. 先进制造. 航空工程. 材料工程. 冶金工程. 机械工程. 固体力学
多尺度力学,宏微观力学,梯度结构材料,界面力学,固体本构关系,应变梯度理论,晶体塑性有限元,离散位错动力学,分子动力学,高熵合金,大数据与机器学习,材料基因,极端力学,高性能材料,材料的增强与增韧
2019-05-24 课题组合作发表的论文“Revealing the inhibition mechanism of grain size gradient on crack growth in gradient nano-grained materials”在期刊 International Journal of Solids and Structures 上在线发表
发布时间:2019-05-24
Abstract
Gradient nano-grained (GNG) materials, in which grain size changes from nano-scale in the surface to micro-scale in the core, have shown superior fatigue property, good strength and ductility. However, crack growth behaviors of GNG materials are studied hardly. In this work, the effect of grain size gradient on crack growth is investigated to reveal the inhibition mechanism of crack growth in GNG materials. The developed model employs a distributed dislocation method to model the evolution of plastic zone. The influence of grain size gradient on the distribution of dislocations in grains and the local stress intensity factor is analyzed. The results show that the sizes of dislocation zone and dislocation-free zone in grains become larger as the gradient of grain size increases. The number of dislocations emitted from the crack tip increases with the grain size gradient increasing, so the shielding effect of emitted dislocations on the crack growth increases and crack blunting becomes more serious. This means that a sharper grain size gradient inhibits the crack growth more effectively. The results in this paper are important for understanding the fracture behaviors of materials with grain size gradient and are helpful for material design and structural optimization.
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