DESENSITIZATION OF SENSITIZED 304 STAINLESS-STEEL BY LASER SURFACE MELTING

Laser surface melting was used to desensitize the surface layer of sensitized 304 stainless steel. The degree of sensitization was determined quantitatively for sensitized and sensitized then laser surface melted samples from the modified ASTM-262 practice E test to be 45% and 0%, respectively, Grain-boundary melting which occurs in the heat-affected zone is believed to contribute the desensitization in the solid. X-ray diffraction results did not show any phase transformation in the melted layer or in the heat-affected zone. The results of the tensile tests indicate that sensitized stainless steel regains its corrosion resistance properties and, in addition, its mechanical properties seem to be enhanced by the laser surface melting.