The Effect Of Carbon On The Performance Of Stainless Steel

Carbon is an important alloying element in the traditional martensitic stainless steel, steel chromium, carbon two elements of a reasonable ratio, the emergence of high, medium and low carbon three types of Fe-Cr-C martensitic stainless steel. The role of carbon is to expand the γ region and improve the hardenability of steel. However, with the increase in the amount of carbon in steel and martensitic stainless steel strength, hardness increase at the same time, the steel plastic, toughness, corrosion resistance, cold forming and weldability to reduce.

The role of carbon in stainless steel, in addition to the martensitic stainless steel has an important impact on the austenitic stainless steel and ferritic stainless steel, as well as duplex stainless steel, generally believe that its disadvantages far outweigh the benefits.

Carbon can improve the strength of stainless steel, but significantly reduce the plasticity and toughness of steel.

Carbon and steel chromium combination, the formation of chromium-rich carbide Cr23C6 at the grain boundary, resulting in chromium depletion caused by intergranular corrosion and a decline in corrosion resistance. For this reason, austenitic, ferritic and duplex steel stainless steel and super martensitic stainless steel in the carbon content is increasingly reduced, for example, austenitic and duplex stainless steel generally require carbon 0.02% to 0.03%; modern ferritic stainless steel and super martensitic stainless steel some grades of carbon is required to be less than 0.01%.