Ultimate Strength of Resistance Spot Welds Subjected to Combined Tension and Shear

Abstract

A new test setup and data concerning the ultimate strength behavior of resistance spot welds in a mild strength steel subjected to combined tension and shear loads are presented. A test plan based on a design of experiments (DOE) with three design factors (coupon width, coupon length, and nugget diameter) was conducted to investigate the influence of the factors on the ultimate strength of the resistance spot welds under different loading angles. In this program, test loads were monotonically applied to the resistance spot weld at a specific angle until the load carrying capacity of the resistance spot weld was exceeded. It was found that the nugget diameter contributes the most (more than 70%) to the total variation of the recorded ultimate strength and that the coupon length has little effect. A deterministic ultimate strength model was proposed to take into account the interaction of in-plane shear and 90° out-of-plane tensile loading in the resistance spot weld. A reliability model was also demonstrated to evaluate the ultimate strength of a single resistance spot weld.

Effect of joint design on the failure behaviour of three-stack-up austenitic stainless steel resistance spot welds

“…Different three-stack-up forms will fracture at distinct initiation angles. Lee et al 25 found that an increase in the rotation angle (α) between the sample interface and the tensile-shear direction reduces the peak load. Different restrictive effects on the weld rotation of the four joint designs were found in the present work.…”