Numerical Analysis of Phenomena During Progressive Hardening of Tool Steel Elements for Cold Work

Abstract

The the paper was presented numerical analysis of progressive hardening tool steel for cold work. Numerical algorithm of thermal phenomena based on the finite element method solution, the formulation Petrov-Galerkin, heat conduction equation In the modeling of phase transformations in the solid state are used graphs of continuous heating and continuous cooling (CHT and CCT). In the model of mechanical phenomena the equilibrium equations and constitutive relations adopted in the rate form. It was assumed that the hardened material has an isotropic or kinematic strengthening. Apart from thermal strains, plastic and structural also taken into account transformation plasticity. Thermophysical size occurring in the constitutive relationship, such as Young's modulus, tangential modulus and yield point depend on temperature and phase composition of the material. To determine the transformation plasticity was used a modified of Lalond model. The model of mechanical phenomena was supplemented by modified plane strain state algorithm, favorable to the mechanical modeling of slender objects. The problem of thermo-elasto-plasticity was solved on the finite element method, the formulation Petrov-Galerkin,. In the numerical example of temperature fields, the phase fractions, stresses and strains was performed, ie. phenomena of progressive hardening slender elements made of tool steel for cold work.