Based on Taguchi orthogonal test,the multi-objective optimization problem of dissimilar thickness DP1180/DP590 resistance spot welding was studied using grey relation analysis.The optimum parameters were derived by considering the responses such as nugget diameter,indentation rate and lower peak load by difference analysis.Analysis of variance(ANOVA)was used to analyze the effects of different parameters on the responses.Based on the results,welding current 9.5 kA,welding time 22 cycles and electrode force ...