Plasticity Performance Of OCr15Ni5WMoVNb Martensite Precipitation Hardening Stainless Steel

0Cr15Ni5WMoVNb is a kind of Martensite Precipitation Hardening Stainless Steel which had good strength and toughness. Firstly, we studied the effect of aging temperature on mechanical property through a series of aging treatments. The experiment results suggested that the aging peak appeared at 450℃after solution treatment. And the strength tried to go down and the toughness to rise with the improvement of aging temperature. It also revealed that at 510℃, the steel could be obtained the favorite toughness with the combined strength, so we suggested it should be used after being aged at 510℃for its stability. Secondly, we discussed the effect of retained austenite on the plasticity of 0Cr15Ni5WmoVNb Martensite Precipitation Hardening Stainless Steel. It was found that the amount of retained austenite raised with the improvement of aging temperature and reached the maximum at 630℃, and then the amount of retained austenite reduced with the further increase of the aging temperature. This might be due to the austenite having maximum stability at 630℃, and with the improvement of aging temperature the stability of austenite decreased, so at room temperature the amount of austenite reduced again. This can also explain when aging at or above 630℃, the amount of austenite was lower than that of just through solution treatment. The retained austenite could improve the plasticity of steel just because its shape and distribution in the one side and transformation induced improvement of plasticity of the deforming process in the other side. Thirdly, we studied the cold-forming property of steel through cold rolling tests. At the basis of past aging treatment experiment which we choosing the most suitable aging temperature, we obtained an optimum solution temperature, which about 1000℃, through a series of solution treatment. Cold deformation steel occurred recrystallization at this temperature and the grain size was quite fine, the strength and the plastic deformation of the steel could be gotten the maximum with the favorite plasticity. Finally, we can get several result from above statement, 0Cr15Ni5WmoVNb Martensite Precipitation Hardening Stainless Steel had good mechanical property after solution in 1000℃and aging in 510℃. Steel had good plasticity and favorite cold-forming after 1000℃solution and 620℃aging treatment.