Finite element analysis of thixoforming process with arbitrary shape die

Numerical simulations for industrial net shape forming application by the finite element method are based on the integral form of the mechanical equations governing the physical process. However, current commercial packages cannot analyze the die filling and solidification for materials in the semi-solid state because they lack material models for liquid and solid materials and do not address segregation of the liquid and solid phases. Thus, this work presents an overview of the development of a new finite element program entitled SEMI-FORM S/W to predict the solid-phase deformation of semi-solid materials (SSM), filling defects and liquid segregation. The automatic mesh generation scheme by the modified looping algorithm using quadrilateral elements is proposed in this present study by a new loop splitting method and a local finite element control. An automatic quadrilateral mesh generator with automatic mesh refinement is developed in order to meet special demands found in the thixoforming process analysis with arbitrary shaped dies by the node renumbering and modifications of the nodal position. The remeshing due to B-spline form is carried out by applying the remeshing criterion. The SEMI-FORM S/W developed in this present study would be recognized as efficient and economical tool for designing and optimizing thixoformed products with arbitrary shaped dies.