FEM simulation of quenching process in A357 aluminum alloy cylindrical bars and reduction of quench residual stress through cold stretching process

The quenching process of A357 aluminum alloy cylindrical bars with 80 mm diameter and with heights of 40, 80, 120, 160, 200 and 240 mm were investigated by using finite element method (FEM) simulation. Heat transfer coefficient was accurately calculated by using a traditional method of inverse heat transfer. Residual stresses caused by quenching of A357 alloy cylindrical bars are inevitable. Residual stresses reduction through cold stretching process was studied by using FEM simulation. Three numerical examples were used to illustrate the accuracy and efficiency of our method. The results show that this quenching model is able to predict the residual stress with high precision. The influence of some factors (quenching water temperature, aspect ratio of cylindrical bar, pre-stretching ratio and stretching rate) on the residual stress of quenched cylindrical bars after cold stretching was investigated.