The prediction of low cycle fatigue for die casting with FEM

The objective of this thesis is using the finite element method to estimate the life of the die casting dies, i.e., the number of thermal cycles before the die surface between die and casting reaches the failure level. To get accurate results, 20-node brick element was used. Also refined meshing with 8 and 20 node brick elements were used in order to increase the accuracy of the solution.; Material model and material properties play an important role in the results of FEM. In this project temperature dependent material properties were developed in the material library for H13 steel and Aluminum 380.; A high resolution FEM thermo-visco-elastic stress analysis was performed for a 1-D simple die casting model and a more complex 3-D dumbbell die casting structure. The effective plastic strain increment was evaluated at die elements. The maximum effective plastic strain increment is always at the die surface between die and casting in this project. The point with the maximum effective plastic strain increment was assumed to be the most likely failure point in a die. The Coffin-Manson equation was used to estimate the life of the die.