With the increase of chromium in stainless steel, not only in the oxidation acid medium corrosion resistance increases, and to improve the stainless steel in chloride solution (including Cl- in the atmosphere and water medium) resistance to stress corrosion, pitting corrosion, crevices corrosion and other local corrosion ability also plays an important role.

The results show that the crevice corrosion resistance of the steel increases with the increase of chromium content, and the crevice corrosion resistance of the steel can reach the best value when the chromium content reaches the normal (20%~22%) range (20.5%) of Al-6XN super austenitic stainless steel.

In stainless steels with high chromium content, especially in ferrite and duplex stainless steels, under the influence of thermal history, intermetallic compounds such as α' and σ (χ) are easily formed in the steels. The plasticity, toughness and corrosion resistance are decreased, and the cold formability and weldability are also deteriorated.

Although the corrosion resistance of steel is reduced and the intergranular corrosion is caused by the formation of carbides between chromium and carbon in stainless steel, the susceptibility to intergranular corrosion decreases with the increase of chromium in steel when the amount of carbon is constant.

In Fe-Cr-C martensitic stainless steel, chromium can improve the hardenability of steel, and increase the strength and hardness of steel. But some other stainless steel, with the increase of chromium, steel strength is also improved, but steel plastic, toughness, cold forming, etc., will be reduced.

Chromium can significantly improve the high temperature oxidation resistance, vulcanization resistance and high temperature strength of stainless steel.