Effects of Fusion Zone Size on Failure Modes and Mechanical Performance of Dual Phase (DP600) Steel Sheets Spot Welds.

Abstract

This paper examines the effects of fusion zone size on failure modes, quasi tension -shear test and energy absorption of resistance spot welds (RSW) of dual phase (DP600) steels. Optical microscopy was used for microstructure investigation. The results showed that some samples failed in pullout failure mode and other samples failed in interfacial failure mode and the failure was located at the base metal. The conventional weld size guidance of 4t0.5 and 5t0.5is not sufficient to produce nugget pullout failure mode for DP600 resistance spot welds.