时效温度对00Cr12Ni10MoTi马氏体时效不锈钢组织与性能的影响

Effect of Aging Temperature on Microstructure and Properties of 00Cr12Ni10MoTi Maraging Stainless Steel

使用X射线衍射(XRD)、扫描电镜(SEM)、电子背散射衍射(EBSD)、透射电镜(TEM)和拉伸和冲击实验等手段,研究了时效温度对00Cr12Ni10MoTi马氏体时效不锈钢的组织和力学性能的影响。结果表明:随着时效温度的升高,实验钢的强度逐渐提高,析出强化效应明显增强。在500℃时效后基体中析出大量棒状Ni3Ti,实验钢的强度达到峰值。随着时效温度的升高,实验钢的室温和低温冲击韧性衰减,在400℃时效后低温(-196℃)冲击功出现最低值51 J。时效温度升高到500℃后,实验钢的冲击韧性回升,因为马氏体基体中生成的逆转变奥氏体抑制了裂纹萌生并缓解其扩展。在500℃时效产生了Ni3Ti析出强化效应和逆变奥氏体韧化效应,使实验钢具有良好的强韧性匹配。

The effect of aging temperature on the microstructure and mechanical properties of00 Cr12 Ni10 MoTi maraging stainless steel was investigated by means of X-ray diffractometer(XRD),scanning electron microscopy(SEM), electron backscatter diffraction(EBSD), transmission electron microscopy(TEM), tensile tester and impact tester. The results show that the strength increases gradually with the increase of aging temperature, through the enhanced precipitation strengthening. A large amount of rod-like Ni3 Ti precipitated on the matrix when aged at 500℃, which leads the strength of the steel to the peak value. The impact toughness at room temperature and low temperature decreases with the increase of aging temperature, and the lowest impact energy at low temperature(-196℃) is 51 J for the steel aged at 400℃, while the impact toughness of the steel increases again when aging temperature continues rising to 500℃, which is related to the formation of reversed austenite in martensite matrix. The existence of austenite phase can effectively inhibit crack initiation and relieve its propagation. Aging at500℃ can effectively exert the precipitation strengthening effect of Ni3 Ti and the toughening effect of reversed austenite, achieving better matching of strength and toughness.