Mechanical properties of a dissimilar aluminum alloy joint welded by hybrid laser-MIG welding

摘要

Two dissimilar Al alloys, 5083-H111 and 6005A-T6, were joined by hybrid laser-MIG welding method. Mechanical properties of the welded joint were investigated and compared. The results show that the tensile strength of the dissimilar joint is 219.8 MPa, 11.7% higher than that of 6005A-T5 joint. After statistical analysis of the fatigue data, the P-S-N curves of the dissimilar joint were obtained. The mean fatigue strength at N-f = 10(7) of the dissimilar joint is 112.5 MPa. The fatigue strength at N-f = 10(7) of the dissimilar joint for a given 10% probability of failure, at a confidence level of 95%, is 101.4 MPa. The fatigue strength at N-f = 10(7) of the dissimilar joint is almost same as that of the 6005A-T6 joint. In welded structure designing, different P-S-N curves should be chosen according to the different service conditions and reliability requirements.