研究了不同Nb含量的LF9合金经固溶+二次时效处理后的力学性能。结果表明，随Nb含量增加，合金的室温和高温强度提高，塑性及韧性下降。经960 ℃固溶+二次时效后，合金中的主要强化相为η相，随着Nb含量增加，η相数量增多，形态由短片状变为长片层状。经1 020 ℃固溶+二次时效后，合金中的主要强化相为(γ′+γ″)，随着Nb含量增加，η相形态从微量的颗粒状变为大量的短片状，对提高合金强度起到了重要作用。经(960~1 020 ℃)固溶+二次时效后，合金中(γ′+γ″)相的尺寸主要为10~100 nm。

The mechannical properties of the LF9 alloy with different Nb content after the solid solution+double aging treatment were studied. The result indicated that with increasing the Nb content the alloy′s room and high temperature strength increased, but plasticity and ductility decreased. After 960 ℃ solid solution+double aging treatment, the alloy′s major strengthening phase was η phase, with increasing the Nb content, the amount of η phase increased and the shape of η phase was changed from short pieces into long pieces. After 1 020 ℃ solid solution+double aging treatment, the alloy′s major strengthening phase was (γ′+γ″), with increasing the amount of Nb, the shape of η phase was changed from minute quantity of particles into a large quantity of short pieces, which is very important for improving strength. After (960-1 020 ℃) solid solution+double aging, the size of most γ′ was 10 to 100 nm.