631 Stainless Steel Sheet
Product Introduction
631, equivalent to China's 0Cr17Ni7Al, is a semi-austenitic precipitation-hardening stainless steel. It is an austenitic-stabilized stainless steel. In the solid solution state, it is an austenitic structure at room temperature. After cold working, cold treatment, or heating to around 750 degrees for adjustment, the austenite can transform into martensite. Further aging treatment can precipitate the second phase on the martensite matrix, thereby strengthening the steel. The role of Al is to form precipitation-hardening phases like (Ni3Al) with other elements. During the aging process, cooling must not be rapid, as it would be difficult to achieve the desired strengthening effect.
Heat Treatment
Solution treatment, quenched at 1000-1100℃;
565°C aging treatment, followed by solution heat treatment at 760±15°C for 90 minutes, then cooled to below 15°C within 1 hour and held for 30 minutes, further heated to 565±10°C for 90 minutes, then air cooled.
510°C aging treatment, followed by solution heat treatment at 955±10°C for 10 minutes, air-cooled to room temperature within 24 hours, then cooled to -73±6°C within 24 hours, held for 8 hours, and finally reheated to 510±10°C for 60 minutes, then air-cooled.
