Effect of Titanium Carbosulfide on Weldability of a Soft-Magnetic Stainless Steel

Soft-magnetic stainless steels have been used for high precision equipment. Their good machinability is rendered by Pb and/or MnS dispersed in them. From the viewpoint of health, Pb is an undesirable element. And MnS deteriorates the corrosion resistance and cold formability. A titanium carbosulfide, Ti4C2S2, is thermodynamically more stable than MnS and it is considered to replace MnS. Effect of titanium carbosulfide on weldability of a soft-magnetic stainless steel has been investigated. Regarding a laser-welded joint of this steel plate and Type304 stainless steel plate, weld bead appearance and shape of penetration were equivalent to those of conventional stainless steel. There were no welding cracks in the weld bead, and there were few microporosities in the case of lower heat input than 0.225kJ/cm. Furthermore, welded joint was ruptured in base metal or HAZ of Type304 stainless steel plate in tensile test, so the mechanical property of welded joint was excellent.