【摘要】 采用金相显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)和电化学萃取相分析等手段,研究了Ⅴ元素对GH4061合金晶粒度、碳化物和γ’/γ"强化相等影响,测试了不同Ⅴ含量试样的室温和750℃拉伸性能以及750℃/460 MPa持久性能,分析了Ⅴ元素对合金显微组织和力学性能的影响。结果表明:GH4061合金中添加Ⅴ元素促进了MC型碳化物和γ’/γ"相析出,使晶粒尺寸小幅减小;Ⅴ元素通过增大γ基体的晶格常数,降低γ基体与γ’相的错配度,抑制了γ’/γ"相在750℃的快速粗化;Ⅴ元素添加对室温拉伸性能影响不大,但可显著提升750℃拉伸强度和持久寿命;当Ⅴ含量为0.4%(质量分数)时,GH4061合金具有最佳的750℃持久性能。更多还原

【Abstract】 The effect of vanadium(V) addition on the tensile-and stress rupture-property at room temperature and 750℃, and the microstructure evolution of GH4061 alloy, including grain size, carbide and γ ′/γ’ phase etc. were investigated by means of tensile-and stress rupture-testing, OM, SEM, TEM and electrochemical extraction and phase analysis of precipitates. The results show that V addition can promote the precipitation of MC-type carbide and γ ′/γ’’ phase, and refine the grain size slightly. With the increase of Ⅴ content, the lattice constant of γ matrix increases, the mismatch between γ matrix and γ ′phase decreases, and the coarsening of γ ′/γ’’ phase at 750℃ is restrained. The addition of Ⅴ does not have significant influence on room temperature tensile property, but apparently benefits the tensile strength and rupture life at 750℃. Furthermore, the GH4061 alloy with 0.4%(mass fraction) Ⅴ addition shows the best stress rupture property at 750℃.更多还原