Author : Joel Mascarenhas 1
Date of Publication :7th June 2016
Abstract: Thermal fatigue stress cracking is one of the major modes of failure in high pressure die casting dies. The aim of this work was to predict the life of the die using fracture mechanics concept and optimize the design to improve its life. In this work, first the crack length was measured at the critical location. Then a transient thermal analysis and thermo- mechanical coupled analysis was performed in ANSYS Workbench on the actual die to obtain maximum stress occurring in the die. The stress value and the crack length measured were substituted in Paris law to obtain theoretical life. The theoretical life was compared with the actual life and an error of less than 5% was obtained. With the successful life estimation, two new designs using an optimized cooling circuit was proposed and same was analyzed using ANSYS. The die providing less thermal stress was chosen as an optimized design.
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