SULFUR TREATMENT OF MAGNESIUM-CONTAMINATED FE-CR-AL ALLOY FOR IMPROVED WHISKER GROWTH

摘要

A method for producing aluminum-containing ferritic stainless steel from a magnesium-contaminated melt such that the steel is suitable for growing oxide whiskers to cover the surface thereof is disclosed. The method comprises adding sulfur to the contaminated melt in an amount sufficient to increase the sulfur content not less than 1.3 times the magnesium content, whereupon the sulfur reacts with the magnesium to render the magnesium inert to whisker growth. The method also preferably comprises an addition of titanium, zirconium or hafnium in amounts sufficient to react with residual sulfur in excess of the amount required for magnesium reaction, thereby mitigating the adverse affect of sulfur on oxide adhesion.