Study On Plastic Finite Element Simulation And Forging Anisotropy Of Precision Forging

Radial forging of barrel is a kind of advanced barrel manufacturing method which is widely used in the world. In the process of machining, the metallic materials have been deformed severely by the forging of the hammer. Texture which is formed by the preferred orientation of the grain after deforming has a great influence on the aeolotropism of forged barrel radial, so it is a new approach researching the properties of forged barrel radial. This article is based on cross-scale finite element method (FEM) and crystal plasticity finite element method (CPFEM), building a research method which connects microscopic texture and macroscopical forging process together. Then, using the texture component acquired by simulation to study the forged barrel radial’s aeolotropism of modulus of elasticity and yield strength.This article discusses the establish method of cross-scale CPFEM model in ABAQUS. Firstly, As for the establishment of the crystal plasticity finite element model, it is achieved by User-defined Material Mechanical Behavior (UMAT) with the theory foundation of crystal constitutive relation and Peirce hardening model. Secondly, plastic finite element model is built to simulate the tensile test in order to fitting the stress-strain curve of tensile test so that we can acquire the parameters of constitutive model. Once more, we combine the interpolation theory, displacement continuum theory and finite element displacement function to derive the transport formula from macroscopic model’s boundary conditions to cross-scale microscopic model’s boundary conditions. Finally, based on Vornoi graph theory and the previous process we illustrated, the CPFEM model can be built by INP file and Python.Using that modeling method, we establish barrel radial forging axisymmetric macroscopic finite element model and microscopic crystal plastic finite element model. The grain orientations can be extracted to draw pole figures and orientation distribution function (ODF) figures by Matlab in order to make a qualitative analysis of texture component by the ODF figures. So we can compare the analysis results with XRD experiment of previous scholar to validate the accuracy of the model.On the basis of texture component, we study the forged barrel radial’s aeolotropism, such as using generalized Hooke law to analyze the effects of texture on barrel material’s modulus of elasticity aeolotropism and monocrystal/bicrystal Schmid factor approximation method to analyze the effects of main texture component on barrel material’s yield strength aeolotropism. Then, we compare the results with vertical and lateral direction experiment respectively. The result demonstrates that the texture component of forged barrel material 30SiMn2MoVA has no effect on modulus of elasticity aeolotropism, but the yield strength has been effected that reducing gradually from rolling direction to lateral direction.