文献类型：会议论文

英文题名：Assessment of Gurson-Tveergard-Needleman model under high stress triaxiality

作者：Zhong, Jiru[1]; Xu, Tong[2]; Guan, Kaishu[1]

机构：[1] School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China; [2] China Special Equipment Inspection and Research Institute, Beijing, 100013, China

会议论文集：ASME 2016 Pressure Vessels and Piping Conference, PVP 2016

会议日期：July 17, 2016 - July 21, 2016

会议地点：Vancouver, BC, Canada

语种：英文

外文关键词：Volume fraction - Pressure vessels - Finite element method - Forecasting - Particle swarm optimization (PSO) - Shear stress - Void fraction - Tensile testing

摘要：The Gurson-Tveergard-Needleman (GTN) model has been widely used to describe ductile fracture. In this paper, a series of tensile tests were carried out on notched specimens to assess the GTN model. The GTN model parameters were calibrated from a smooth tensile specimen by a hybrid particle swarm optimization, and the reliability of the calibrated parameters was verified by the profile of the smooth tensile specimen. The calibrated parameters were used to predict the ductile fracture of notched specimens. A comparison of fracture initiation sites between simulations and experiments indicates that the GTN model has a good performance on predicting fracture initiation site but fails at predicting fracture moment. The assessment of the transformability of the GTN model parameters was performed by comparing the load-displacement curves between simulations and experiments. It is observed that the GTN model parameters are material constant, except the critical void volume fraction fc. The influence of stress triaxiality on the critical void volume fraction fc is also discussed. Copyright ? 2016 by ASME.