Characterization of residual stresses in dissimilar metal rotary friction welds with and without an interlayer

Dissimilar metal welding (DMW) has been commonly adopted in a wide range of industrial applications. However, traditional arc welding for joining high-strength low alloy (HSLA) steel to heat-treatable ferritic or austenite stainless steel can be problematic as it is time consuming, prone to cracking and introduces significant residual stresses to a structure. Given these challenges, rotary friction welding (RFW), which is a solid-state joining process, seems appealing for such manufacturing conditions. In this work, we focus on the first stage of our research on RFW for dissimilar metal welds, in which we investigate the potential benefits of introducing a dissimilar metal interlayer. Simple solid cylinders of S355 low carbon steel (not heat treatable) and ASTM A182 F22 low alloy steel (heat treatable) have been used in this work to investigate the residual stresses and their distributions with in the samples at different states (F22 sides with/without a dissimilar interlayer, full welds with/without a dissimilar interlayer and/or post weld heat treatment). The total beam time request is 3 days for measurements in 74 locations and two orientations, to capture the development of residual stresses at each manufacturing stage. The results of this work will be published at the earliest opportunity.