文摘
The present paper deals with the joining of 22MnMoB hot-stamping annealed steel carried out by the spot welding process. Microstructural characterization, microhardness testing and tensile-shear testing were conducted. The effects of the welding parameters, including the electrode tip diameter, welding current, welding time and electrode force upon the tensile-shear properties of the welded joints, were investigated. The results showed that a weld size of 9.6 mm was required to ensure pullout failure for the 1.8-mm-thick hot-stamping annealed steel sheet. The welding current had the largest influence upon the tensile-shear properties of the 22MnMoB steel welded joint. The bulk resistance should play an important role in the nugget formation. In pullout failure mode, failure was initiated at the heat-affected zone, where softening occurs owing to the tempering of martensite.