Modeling and 2-D discrete simulation of dislocation dynamics for plastic deformation of metal
Two methods are employed in this paper to investigate the dislocation evolution during plastic deformation of metal.One method is dislocation dynamic simulation of two-dimensional discrete dislocation dynamics (2D-DDD),and the other is dislocation dynamics modeling by means of nonlinear analysis.As screw dislocation is prone to disappear by cross-slip,only edge dislocation is taken into account in simulation.First,an approach of 2D-DDD is used to graphically simulate and exhibit the collective motion of a large number of discrete dislocations.In the beginning,initial grains are generated in the simulation cells according to the mechanism of grain growth and the initial dislocation is randomly distributed in grains and relaxed under the internal stress.During the simulation process,the externally imposed stress,the long range stress contribution of all dislocations and the short range stress caused by the grain boundaries are calculated.Under the action of these forces,dislocations begin to glide,climb,multiply,annihilate and react with each other.Besides,thermal activation process is included.Through the simulation,the distribution of dislocation and the stress-strain curves can be obtained.On the other hand,based on the classic dislocation theory,the variation of the dislocation density with time is described by nonlinear differential equations.Finite difference method (FDM) is used to solve the built differential equations.The dislocation evolution at a constant strain rate is taken as an example to verify the rationality of the model.
Dislocation Dynamics Modeling and Simulation Plastic Deformation
Juan Liu Zhenshan Cui Hengan Ou Liqun Ruan
National Die & Mold CAD Eng.Research Center,Shanghai Jiao Tong University,Shanghai,China;Department National Die & Mold CAD Eng.Research Center,Shanghai Jiao Tong University,Shanghai,China Department of Mechanical,Materials and Manufacturing Engineering,Nottingham University,Nottingham,UK Department of mechanical engineering,Kumamoto University,Kumamoto,Japan
国际会议
沈阳
英文
345-353
2013-07-06（万方平台首次上网日期，不代表论文的发表时间）