Definition - What does Heat Tint mean?
Heat tint is the result of the oxidation that can occur when welding stainless steels. Heat tint can occur in the weld metal and also in the base metal in the area that surrounds the fusion zone. Heat tint can be detrimental to the corrosion resistance of stainless steel.
Corrosionpedia explains Heat Tint
Heat tint occurs when a stainless steel is exposed to oxygen during the welding process. This typically is a result of inadequate shielding or excessive heat during the welding process. When the chromium in stainless steel combines with oxygen, it changes to colors that are not typical of the original stainless steel. This oxidized chromium is pulled from the base metal. The result is an underlying base metal that has a lower amount of chromium, which is more likely to be affected by corrosive environments.
From an aesthetic perspective, heat tint is generally considered undesirable. Heat tint can also have negative ramifications on stainless steel's ability to resist corrosion.