Analysis of the problems in spot welding AISI 301 high-strength austenitic stainless steels and galvanized steel plates

Abstract

A study was carried out in order to evaluate the possible problems linked to spot welding of galvanized steel plates and high-strength austenitic stainless steels (AISI 301). Testpieces were made by joining two edges of galvanized plate by an AISI 301 steel plate. These testpieces were loaded at approx. 50% of σ_0.2 of the stainless steel. Two steels of the same type but of different origin and supply were used: the first (steel A) was sensitised and sometimes failed, even after a few days; the second (steel B) was solution-treated and did not fail.

Besides the fracture morphologies, the microstructures of the two stainless steels, the welding defects and the presence in the steels of hydrogen from the galvanized plate during fusion of the spot weld were discussed.