Experimental Study on Effect of Nugget Diameter on Residual Stresses in the AISI 1008 Spot Weldments

Manufacturing and production methods such as welding with non uniform deformation cause significant residual stresses. In automotive industry, resistance spot welding process was used to joint chassis and body parts widely. In present research, with utilization of the hole drilling method and using the resistance strain gage, effects of nugget diameter variation on residual stresses in AISI 1008 spot weldments were investigated. The distributions of radial and hoop residual stresses in edge of the nugget and longitudinal and transverse residual stresses in the nugget center of eight standard specimens with the different nugget diameters were determined and illustrated. The results show that by increasing the nugget diameter, the radial and hoop residual stresses were decreased.