Abstract The microstructure, element segregation and γ/γ′ interface characters of polycrystalline Ni3Al-based superalloys under conventionally solidified (~10 K/s) and rapidly solidified (~103 K/s) conditions were investigated. Cr and Fe are primarily partitioned into the γ phase while Al and Ni are into γ′ phase. However, rapid solidification rate of spray casting alloy improves the solubility of Cr and Fe elements at the expense of Al in γ′ phase, which decreases the lattice parameters of γ and γ′ phases. Moreover, it further increases the absolute value of γ/γ′ lattice misfit and contributes to the formation of (100) plane misfit dislocations in γ/γ′ interface. As a result, spray casting specimen possesses higher hardness (6.5 ± 1.0 GPa) and elastic moduli (166.4 ± 15.9 GPa) than that in as-cast alloy with lower solidification rate.

中文翻译：

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多晶Ni3Al基高温合金中γ'析出物和γ/γ'界面的表征

摘要 研究了多晶 Ni3Al 基高温合金在常规凝固 (~10 K/s) 和快速凝固 (~103 K/s) 条件下的显微组织、元素偏析和 γ/γ' 界面特征。Cr 和 Fe 主要分配到 γ 相，而 Al 和 Ni 分配到 γ' 相。然而，喷铸合金的快速凝固速度提高了 Cr 和 Fe 元素在 γ' 相中的溶解度，而牺牲了 Al，从而降低了 γ 和 γ' 相的晶格参数。此外，它进一步增加了γ/γ'晶格失配的绝对值，有助于在γ/γ'界面形成（100）面失配位错。因此，与凝固速率较低的铸态合金相比，喷铸试样具有更高的硬度（6.5 ± 1.0 GPa）和弹性模量（166.4 ± 15.9 GPa）。