Abstract
Dissimilar joint of steel and aluminum alloy was produced by YAG laser welding. Maximum tensile shear strength was about 86 % of tensile strength of aluminum alloy. About 10 μm thickness intermetallic layer was observed at the interface of the joint. Temperature distribution was calculated by BEM (Boundary Element Method) analysis combined with the results of temperature measuring test. According to BEM analysis, maximum temperature at the interface was between melting point of aluminum and steel. Diffusion occurred during laser welding between solid state steel and liquid state aluminum to produce thin intermetallic layer
