Technical University Clausthal-Zellerfeld, Institute of Welding and Cutting (Clausthal, Germany):

Veit J., Mag. Eng., Scientifi c Researcher, e-mail: j.veit@sz.szmf.de
Wesling V., Prof., Dr. Eng., Institute Director
Schram A., Dr. Eng., Scientifi c Director

Salzgitter Mannesmann Forschung GmbH (Salzgitter, Germany):

Flügge W., Dr. Eng., Head of Assembling Technology Division
Fritzsche Ch., Dr. Eng., Expert on Pressure Welding

High-manganese TWIP-steels off er a high potential for lightweight design due to their outstanding mechanical properties. In order to fulfill these expectations, a simple processability is essential. This includes good resistance spot weldability, especially for the automotive industry. Investigations on XSD600 sheet steel (1.5 mm thick) have been conducted and displayedthat this material can be successfully subjected to contact point welding without forming hot cracks, unlike its high cracking ability. The point welding unit should provide in this case minimal force on electrodes equal to 12 kN. Negative effect on service life and depth of replaceable electrode end stamp for electrodes with force 14 kN was not revealed. In order to use the chosen combination of parameters in serial production and based on requirements on obtaining of welding points without hot cracks, it is necessary to examine additionally the effect of deviations, e.g. for sheet cracking. Due to gap between the pieces, a part of force on electrodes is consumed for their reduction and, respectively, doesn’t use effectively in welding process, so its effect on hot cracking have to be estimated in each practical case.

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