Welding of heat-resistant steel for automobile applications

Because of the configuration diversity and the ever greater possibilities in cast steel technology and, in particular, in precision casting technology in the wake of technological development, high-alloyed semi-finished cast products are playing an increasing role for component suppliers in the automobile industry. Ever more significance is being attached to the fabrication technologies utilised for the further processing of high-alloyed cast steel and thus to welding as well. During the joining of heat-resistant steel materials (e.g. for turbocharger components), the primary problem is a high susceptibility to cracking.

The aim of a research project carried out at SLV Halle was to develop new technologies for joining cast steel materials susceptible to cracking in a reliable process in order to be able to offer the user economically viable possibilities of manufacturing high-quality welded joints appropriate for the requirements. The investigations focused on using the newest arc and laser technologies which permit the minimisation of the heat input into the components. The fundamental possibilities of the pressure welding processes for the joining of engine components were investigated as an alternative to the fusion welding processes. A weld manufactured by means of plasma-arc powder joining welding on a material for utilisation in an internal combustion engine is portrayed on the figure as an example of the elaborated results.