1Cr12Ni2WMoVNb(GX—8)钢的回火转变研究

Study on Tempering Transformation of 1Cr12Ni2WMoVNb(GX-8) Steel

本文叙述了1Cr12Ni2WMoVNb(GX—8)钢的回火转变机制的研究结果。该钢经300℃回火析出Fe_3C型碳化物,400～500℃回火析出M_7C_3与M_2X,500～600℃回火析出M_2X和M_(23)C_6,600℃以上回火析出M_(23)C_6。由于在不同温度下回火,析出的碳化物类型、形态、数量和分布的不同,因而使钢具有不同的物理、力学和化学性能。

The tempering transformation of ICr12Ni2WMoVNb(GX-8) steel has been investigated. It is found that after the tempering at 300℃, the decomposition of martensite and M3C precipitation is observed. After the tempering within the temperature range of 400~ 500℃ , the quantity of carbides in the steel is reduced since the M3C is dissolved into the matrix, and then carbide M7C3is precipitated. After the tempering of 500~ 600℃, Carbide M7C3is transformed into M2X. The amount of carbides in the steel is incresed rapidly with the increasing tempering temperature. As the tempering temperature is higher than 600℃, carbide M23C6is precipitated and grown up.