Microstructure and Mechanical Properties of Electrical Resistance Spot Welded Interstitial Free Steel Joints

In this paper, empirical relationships were developed to predict the tensile shear fracture load and cross tensile shear fracture load of the Resistance spot welded Interstitial free steel joints by incorporating process parameters namely, welding time, weld power and electrode force. The experiments were conducted based on a three factor, five level, and central composite rotatable design matrixes. Sensitivity analysis was carried out and compared with the relative impact of three process parameters on tensile shear strength and cross tensile shear strength to verify the measurement errors on the values of the uncertainty in estimated parameters. The results indicate that the weld power has the greatest influence on tensile shear strength and cross tensile shear strength, followed by welding time and electrode force.