The Simulation On Deformation Texture And Damage Of Face-centered Cubic Metals By Crystal Plasticity

Understanding the anisotropy of metals has always been an important topic,because this anisotropy is closely related to mechanical properties of materials.Especially in engineering,it will be a great deviation if you don't consider the organization and structure within the material when evaluating the performance and life of parts.Although the researchers developed various plastic mechanical models to describe and predict the mechanical properities of metal materials,they have their own focus.For example,some researchers focused on showing the final texture and analyzed less of the evolutionary process;Some researchers focused on verifying the rationality of the simulation but had less explanation for the mathematical calculation;Some researchers focused on the damage but didn't consider the initial texture,etc.In this paper,we try to study the texture and damage in the framework of crystal plasticity theory.The goal is to develop a feasible texture simulation algorithm and show the evolution of texture.At the same time,the relationship between damage evolution and initial texture will be discussed.It is hoped that the research results will lay a foundation for revealing the texture and damage evolution of metal materials in plastic deformation process,and it's also hoped that the theory of crystal plastic mechanics can be used to provide some reference for various damage prediction of engineering materials and structures.The main research contents are as follows.1.Based on the theory of crystal plastic mechanics and texture theory,the texture simulation and analysis of unidirectional stretching and compression and plane strain compression are carried out.It is found that the crystal plane in uniaxial tension and unidirectional compression is rotating about the strain-loa.ding axis,and in plane strain compression the crystal planes' rotation type is translation.These provide a new perspective for the judgment of texture type,that is,the texture type can be predicted by measuring the rotation rules of the crystal plane.2.Under the framework of theory of crystal plastic mechanics and damage mechanics,a ductility damage model based on the theory of crystal plastic mechanics is derived.3.Based on the ductile damage model under the theory of crystal plastic mechanics,the relationship between damage and lattice rotation and initial orientation is discussed under unidirectional tension and plane strain tension.The results show that in the initial random orientation,the extending direction of damage and stretch direction are 45 degrees.Under non-random orientation,the damage bands are basically either parallel or vertically extended,but the extending directions and damage values are both different.