Weld seam testing
Local determination of strength
Examinations at SLV Halle
Weld seam testing - determination of local strengths
Investigation of the local strength values in a resistance spot weld joint
The indentation method according to DIN SPEC 4864 was successfully applied in the context of research work on the topic of “resistance spot welding”. In the classical way, the hardness was determined beforehand by means of hardness testing and conclusions were drawn about the strength. However, the limits of the meaningfulness of the hardness value were quickly reached. It was hardly possible to make reliable statements about the yield point or the hardening behaviour. Even the conversion of hardness into tensile strength was, for example, only possible with a high fault tolerance in the case of austenitic materials or aluminium alloys.
The indentation process now provides the desired properties for the strength (yield strength Rp0.2 and tensile strength Rm) of the welded joint.