MODELING AND IMPROVEMENT OF ANISOTROPIC STRENGTHENING OF ORTHOTROPIC CRYSTALLINE MATERIALS

Abstract

Sheet material subject to stamping, as a rule, has an anisotropy of mechanical properties due to the brand of the material and the technological modes of its production. The anisotropy of the mechanical properties of the workpiece material can have both a positive and a negative effect on the steady course of technological processes of pressure metal processing. In the processes of plastic deformation, the initial anisotropy of the mechanical properties changes and depends on the processing modes. When analyzing the technological processes of processing anisotropic metals by pressure, the initial anisotropy of the mechanical properties is mainly taken into account. Accounting for the influence of the initial anisotropy is carried out within the framework of an ideal plastic or isotropic body that is being strengthened. However, these assumptions do not allow us to estimate the change in anisotropy of mechanical properties during plastic processing. Most of the existing theories of anisotropic strengthening of an initially isotropic and anisotropic body are based on isotropic expansion and movement of the load surface in the stress space and differ from each other in the approaches to describing the movement of the center of the load surface, which can be specified in the form of finite and differential relations. They are designed for small elastoplastic deformations. The article gives the main ratios that must be used in the analysis of cold stamping processes of orthotropic anisotropically strengthening materials and proposes mathematical models of anisotropic strengthening of orthotropic crystalline materials. The deformation intensity value and components of the strain tensor in the main axes of anisotropy are used as strengthening parameters, and the accumulated amount of damage is also taken into account.