STUDY ABOUT THE INFLUENCE OF ANISOTROPIC PLASTIC MATERIAL BEHAVIOR ONTECHNICAL FORMING PROCESSES

Because of the process of manufacturing sheets used in technical formi ng processes show usually a microstructure in which the grains of the polycrystalline material own the same orientation. The consequence is anisotropic material properties depending on the direction. The influe nce of that anisotropy on the plastic deformation of metals is investi gated by Finite Element (FE) simulations. At first a model describing the plastic anisotropy by different yield stresses in different direct ions is proposed. The different plastic behaviour for tensile and comp ressive stress is also taken into account as well as plastic volume ch ange. A simple example of application is a sheet under a biaxial balan ced load. In FE simulations the beginning of plastification is shown b y the curves of plastsic strains for different directions. At the end the study concerning plastic anisotropy is completed by the simulation of the sheet bending in V-forging die. The computations here are conc entrated on the punch force at the beginning of plastification.