Hardness prediction of weldment in friction stir welding of AA6061 based on numerical approach

The purpose of study is to predict hardness of weldment in friction stir welding(FSW) process of AA6061 based on numerical approach. FE-simulation was performed to describe material behaviour in FSW process. In this study, bonding criteria, used in porthole die extrusion of aluminium alloy, was applied for FE-simulation of FSW. Mechanical properties of weldment were also predicted by quench factor analysis(QFA) considering volume fraction for untransformed during quenching. Experiment of FSW was preformed to verify prediction method by FE-simulation with bonding criteria and QFA. As a result, hardness of weldment in FSW process of AA6061 can be precisely predicted by the suggested method.