Residual stress measurements and model validation of single and double pulse resistance spot welded advanced high strength steel

Advanced high strength steels (AHSS) are increasingly used in automotive industry; thousands of resistance spot welds are applied to car body-in-white. High alloying levels of AHSS result in lower weldability. Residual stresses play an essential role on the formation of defects and the mechanical performance of the weld. An electrical-thermal...

Study of solidification cracking in advanced high strength automotive steels

Advanced high-strength steels (AHSS), which are increasingly used in the automotive industry, meet many functional requirements such as high strength and crash resistance. Some of these steels contain high amounts of alloying elements, which are required to achieve the necessary mechanical properties, but render these steels susceptible to weld...

Investigation on hot cracking during laser welding by means of experimental and numerical methods

Hot cracking during laser welding of Transformation Induce Plasticity (TRIP) steel at the edges of steel flanges can be a problem. In this study, modified hot cracking tests were performed by welding on a single-side clamped specimen at various distances from the free edge, while the heat input and external constraints remained constant. In situ...

Revealing internal flow behaviour in arc welding and additive manufacturing of metals

Internal flow behaviour during melt-pool-based metal manufacturing remains unclear and hinders progression to process optimisation. In this contribution, we present direct time-resolved imaging of melt pool flow dynamics from a high-energy synchrotron radiation experiment. We track internal flow streams during arc welding of steel and measure...

Study of solidification cracking in a transformation-induced plasticity-aided steel

In situ high-temperature laser scanning confocal microscopy is applied to study solidification cracking in a TRIP steel. Solidification cracking was observed in the interdendritic region during the last stage of solidification. Atom probe tomography revealed notable enrichment of phosphorus in the last remaining liquid. Phase field...