文献类型：期刊文献

英文题名：Experimental and numerical studies of nonlinear ultrasonic responses on plastic deformation in weld joints

作者：Xiang, Yan-Xun[1]; Zhu, Wu-Jun[1]; Deng, Ming-Xi[2]; Xuan, Fu-Zhen[1]

机构：[1] Key Laboratory of Pressure Systems and Safety, Ministry of Education, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China; [2] Department of Physics, Logistics Engineering University, Chongqing, 400016, China

年份：2015

卷号：25

期号：2

外文期刊名：Chinese Physics B

收录：EI(收录号：20160701930310)

语种：英文

外文关键词：Microstructure - Stress-strain curves - Chromium alloys - Vanadium alloys - Finite element method - Molybdenum alloys - Heat affected zone

摘要：The experimental measurements and numerical simulations are performed to study ultrasonic nonlinear responses from the plastic deformation in weld joints. The ultrasonic nonlinear signals are measured in the plastic deformed 30Cr2Ni4MoV specimens, and the results show that the nonlinear parameter monotonically increases with the plastic strain, and that the variation of nonlinear parameter in the weld region is maximal compared with those in the heat-affected zone and base regions. Microscopic images relating to the microstructure evolution of the weld region are studied to reveal that the change of nonlinear parameter is mainly attributed to dislocation evolutions in the process of plastic deformation loading. Meanwhile, the finite element model is developed to investigate nonlinear behaviors of ultrasonic waves propagating in a plastic deformed material based on the nonlinear stress-strain constitutive relationship in a medium. Moreover, a pinned string model is adopted to simulate dislocation evolution during plastic damages. The simulation and experimental results show that they are in good consistency with each other, and reveal a rising acoustic nonlinearity due to the variations of dislocation length and density and the resulting stress concentration. ? 2016 Chinese Physical Society and IOP Publishing Ltd.