While solidification behavior has been investigated in several nickel-based superalloys, few investigations have focused on the meticulous study of solidification behavior in such a highly alloyed and high γ′ volume fraction-containing alloy as GH4151. In this study, several material characterization techniques were employed to identify phase types, illustrate the morphology of precipitates, and detect composition characteristics. In addition, differential scanning calorimeter and isothermal solidification quenching experiments were used to explain the solidification sequence. It has been confirmed that (Nb,Ti)C carbides, η phase, eutectic (γ + γ′), Laves, Ni 5 Ce, and γ′ phase were found in the as-cast GH4151. The solidification sequence was determined as follows: L → L + γ → L + MC → L + η → L + (γ + γ′) → L + Laves → L+Ni 5 Ce, and γ → γ′. Combined with electron probe micro-analysis, the results show that Nb, Ti, Mo, and V are significantly enriched in the interdendritic region, which has elemental degrees of segregation such that Nb > Ti > Mo > V, while Al, Co, Cr, W, and Ni are enriched within the dendritic arms, whose degree of segregation is W > Al > Ni > Co > Cr.

中文翻译：

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一种新型高合金镍基高温合金凝固行为的研究

虽然对几种镍基高温合金的凝固行为进行了研究，但很少有研究集中在对 GH4151 等高合金化和高 γ' 体积分数合金的凝固行为进行细致研究。在本研究中，采用了多种材料表征技术来识别相类型、说明沉淀物的形态并检测成分特征。此外，利用差示扫描量热仪和等温凝固淬火实验来解释凝固顺序。已经证实在铸态 GH4151 中发现了 (Nb,Ti)C 碳化物、η 相、共晶 (γ + γ')、Laves、Ni 5 Ce 和 γ' 相。凝固顺序确定如下：L → L + γ → L + MC → L + η → L + (γ + γ′) → L + Laves → L+Ni 5 Ce，和γ → γ′。