Abstract
Fatigue strength of lapped weld joint in use of fatigue improvement welding process (MX-MIG process) which can improve the weld toe shape and decrease the residual tensile stress was investigated. As a result, fatigue limit at the weld toe of MX-MIG process could improve to 1.6-1.8 times compared with conventional welding process. Moreover, fatigue strength at the start point of lapped weld joint which has the possibility of crack initiation site in actual automobile components was improved with the combination of MX-MIG process and the extension bead. The light-weighting of chassis parts will be possible by application of MX-MIG process.
