SURFACE TREATED STAINLESS STEEL HAVING EXCELLENT RUST RESISTANCE, STAINLESS STEEL HAVING EXCELLENT COATING FILM ADHESION TO FLUORORESIN AND METHOD FOR MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a stainless steel having an excellent adhesion property to a fluororesin having excellent weatherability. SOLUTION: The stainless steel having the excellent coating film adhesion property to the fluororesin characterized in that a nonmetallic inclusion containing Mg exists at an area ratio of >=0.01% within a thickness range of a surface layer of at least 100μm. The method for manufacturing the same consists in adding 0.0005 to 0.05 mass % Mg into molten stainless steel to deposit Mg oxide or Mg sulfide and subjecting the stainless steel to ordinary hot rolling-descaling-cold rolling-annealing-descaling, then grinding by mechanical polishing to prescribed surface roughness to scalp the Mg in the inclusions and applying a fluororesin coating thereon. The high adhesion property is obtained by the adsorption of the Mg into the inclusion of the fluorine in the coating film.