Abstract
Keywords:
Spot weld, Cold working, Aluminum, Fatigue, Residual Stress, Microhardness
Abstract
Aluminum Resistance Spot Weld (Al RSW) is an enabling technology for body assembly of low mass fraction vehicles. Due to the unreliable durability of weld-bonded joints, applications of Al RSW are limited. This study presents experimental investigation on the use of a post-weld cold working process to improve the fatigue strength of Al RSW. The post-weld cold working process includes special shaped indenters that are pressed or driven into the structure to induce compressive residual stresses. The mechanical properties of the post-weld cold worked Al RSW were investigated, including the experimental results of fatigue and micro-hardness tests. The effect of the post-weld cold working process on the fatigue strength of the Al RSW was investigated. Comparisons of the mechanical properties and qualitative results between the as-welded RSW specimens and the post-weld cold worked RSW specimens are discussed.