PROPERTY OF FRICTION STIR WELDED 2024-T3 ALUMINUM ALLOY

Fatigue crack propagation tests on friction stir welded aluminum alloy sheets were carried out to investigate the effect of residual stress on the crack propagation rate. In these tests, the effect of the inclination angle of the weld line on the direction of crack propagation was also investigated. The test results show that crack propagation rate is accelerated by high tensile residual stress around the weld line. The angle of the weld line does not affect the crack propagation rate and direction. This behavior of crack propagation cannot be explained by the consideration of residual stress value alone. The estimation of effective stress range from the crack opening stress is required to satisfactorily evaluate the crack propagation rate of friction stir welded specimens.