Revisiting transport phenomena and their role in intermixing during dissimilar laser beam welding

A study was conducted in order to understand the intermixing during welding dissimilar steel materials in overlap condition. Based of a manganese steel, different combinations were investigated considering convective transport processes, local alloy constitution and mechanical properties, and the underlying metallurgical effects. The analysis reveal an uneven distribution of alloying elements where the ferritic and martensitic phases are largely suppressed. Micro hardness measurements show hard spots but leading to a ductile character of the weld metal. The investigation show the strong effects of the processing parameters on the degree of intermixing and the inhomogeneity of the weld metal.