Influence of surface treatment on corrosion resistance of Cr-Ni steel

Corrosion resistance of Cr-Ni steels is provided by the self-healing layer of Cr2O that forms spontaneously on the surface of steel. During the process of welding, heat input leads to the destruction of the oxide layer, chemical surface oxidation and formation of thermal oxides of different chemical composition and thickness from the original oxide layer, which impairs corrosion resistance of stainless steels. This paper presents test results of the resistance towards pitting corrosion of AISI 304L stainless steel, after buildup TIG welding and subsequent chemical and electrochemical surface treatment, whereat efficiency of "classical" and "environmentally- friendly" heat-tint removal agents was studied.