Abstract The microsegregation of niobium during solidification and the resulting gradient of this element from dendrite cores to the segregated regions were studied by the formation of precipitate phases, i.e. Tag method. The effect of homogenization on the distribution of precipitates and avoiding the formation of the precipitate-free zones were discussed. Accordingly, the formation of γ″ and delta (δ) phases was correlated to the local Nb content and aging temperature in Inconel 718 superalloy in the as-cast structure and rationalized based on the thermodynamics analysis.

中文翻译：

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阐明微观偏析对铸态含铌高温合金中析出现象的影响

摘要 通过析出相的形成，即Tag 方法，研究了铌在凝固过程中的微观偏析以及该元素从枝晶核到偏析区域的梯度。讨论了均质化对沉淀分布和避免无沉淀区形成的影响。因此，γ″和δ(δ)相的形成与铸态Inconel 718高温合金中局部Nb含量和时效温度相关，并基于热力学分析进行合理化。