利用物理—化学相分析和差热分析法研究了硅对Ni-Cr-Co-W-Al-Ti-Nb-Hf-C系合金结晶时的相成份变化及相变过程的影响,合金中硅含量由0.05％增加至0.4％,引起不等轴共晶γ-γ′析出分量的增加,并从熔融合金中补充析出以HfC为基的Me_C和MeC型碳化物。在高温等温持久及蠕变条件下,硅引起碳化物转变,加剧了γ′-相的凝聚,这样就降低了合金的寿命和瞬时塑性。 The influence of silicon on the phase composition and phase transformation during the crystallization of Ni-Cr-Co-W-Al-Ti-Nb-Hf-C alloy was studied by means of physical-chemical analysis and differential thermal analysis. The content increased from 0.05% to 0.4%, which led to the increase of precipitation fraction of γ-γ inequivalent eutectic, and the precipitation of HfC-based Me_C and MeC carbides from the molten alloy. Under isothermal and long-lasting creep conditions at high temperature, silicon causes carbide transformation, aggravating the γ’-phase coalescence, thus reducing the alloy’s lifetime and transient ductility.