铌含量对LF9合金性能的影响

Effect of Nb Content on Properties of LF9 Alloy

研究了不同Nb含量的LF9合金经固溶十二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目相，随着Nb含量增加，叩相数量增多，形态由短片状变为长片层状。经1020℃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，呀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（960-1020℃）固溶＋二次时效后；合金中（γ′ ＋γ″）相的尺寸主要为10～100nm。

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 ηphase, with increasing the Nb content, the amount of η phase increased and the shape of ηphase 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 ηphase 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.