采用Thermo-Calc热力学计算软件,对T122铁素体耐热钢钒含量变化对平衡析出相及A3、A4点的影响进行了研究.结果表明,T122钢的主要平衡析出相为M23C6、MX和Laves相.当钒质量分数在0.15%以下时,将析出极少量的Z相,且其随着钒含量的增加析出量呈直线下降;当钒质量分数在0.28%以上时,将析出两种不同的MX相,随着钒含量的增加MN相的比例下降,而M(C,N)相的比例增加.钒含量的变化对M23C6和Laves相的影响甚小.钒作为封闭奥氏体元素,增加钒含量,铁素体与奥氏体的转变区域将变小. The thermodynamic calculation software of Thermo-Calc was used to study the effect of vanadium content in T122 ferritic heat-resistant steel on the equilibrium precipitates and A3, A4 spots.The results show that the main equilibrium precipitates of T122 steel are M23C6, MX and Laves When the mass fraction of vanadium is below 0.15%, a very small amount of Z phase will be precipitated, and the amount of precipitation will decrease linearly with the increase of vanadium content. When the mass fraction of vanadium is above 0.28%, two different MX phase, with the increase of vanadium content, the proportion of MN phase decreased and the proportion of M (C, N) phase increased.The variation of vanadium content had little effect on M23C6 and Laves phase.Vanadium as a closed austenite element increased Vanadium content, ferrite and austenite transformation area will become smaller.