WeldForming: a new inline process combination to improve weld seam properties

The high heat input during fusion welding leads to transformations of the microstructure in the area subjected to welding, mostly resulting in a heterogene crystalline structure and an overall deterioration of the mechanical properties. To reduce the detrimental effect, posttreatment processes which are typically separated from the actual welding process are state of the art. The present work shows the new methodology, WeldForming, which intends to eliminate subsequent treatment processes. The new in-line process combination harnesses the synergies of a welding and a rolling process to ultimately prevent the typical zone formation of the heat affected zone. Experimental investigations combined with a detailed numerical simulation of the coupled welding and forming process indicate the functional proof of the new methodology. The validation of the numerical model is carried out with the aid of temperature profiles, cross sections, and microstructure analysis as well as flow curves determined by upsetting tests on thermomechanical simulation systems.