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对低Al，高Ti,Nb（合金A）和高AI、低Ti，Nb（合金B）两种成分特征的Fe－Ni－Cr－Co－Nb－Ti－Al合金宏观和微观铸态组织的观察分析表明，合金A凝固速度较快，柱状晶区较大：两青枝晶间及铸态晶界上都分布着较多块（厚片）状富含Nb和Ti的MC和Laves相多晶体；合金B柱状晶区晶界Laves相较多；合金A晶界MC和Laves相附近析出魏氏体状γ’和η相及胞状η相；合金B中γ′的尺寸仅约为合金A的1／10研究了凝固过程中，两者晶界MC和Laves相的形成机制和差异，以及两者等轴晶区和往状晶区晶界附近魏氏体状、胞状组织或尺寸较大的准球形γ′的差异讨论了合金A中魏氏体状和胞状相的形成机制及γ′通过层错向η相的转变机理
The macroscopic and microscopic as-cast microstructures of Fe-Ni-Cr-Co-Nb-Ti-Al alloys with low Al, high Ti and Nb (alloy A) and high AI, low Ti and Nb (alloy B) The observation and analysis show that the solidification rate of alloy A is faster and the columnar crystal area is larger. There are many massive (thick) Nb and Ti-rich MC and Laves phases in the two green dendrites and the as-cast grain boundary Crystal. The Laves phases in the B columnar grain boundary of the alloy B are more than those in the alloy B; the γ ’and η phases and the η phase are precipitated in the vicinity of the grain boundaries MC and Laves, and the size of γ’ 1/10 of the solidification process, the formation of the two grain boundaries MC and Laves phase mechanism and differences, as well as the two equiaxed and forward grain boundaries near the grain boundary Westendo, cellular or larger size The difference of the quasi-spherical γ ’discussed the formation mechanism of the W-shaped and cellular phases in alloy A and the transformation mechanism of γ’ through the layer-to-n-phase