Al–Ce alloys possess desirable elevated-temperature performance due to the high stability of Al₁₁Ce₃ phases. The morphology and size of the Al₁₁Ce₃ phases play a significant role in determining the strengthening effect in Al–Ce alloys. In this paper, the effect of Sc/Zr addition on the microstructure, mechanical properties, and thermal stability of a hypereutectic cast Al–Ce alloy was investigated. The results demonstrated that Sc and Zr atoms could adsorb on the Al₁₁Ce₃ phase surfaces and control the growth process in the 0.13 wt % Sc-0.06 wt % Zr addition alloy, along with the size of primary Al₁₁Ce₃ phases was refined from ∼79 μm to ∼56 μm. As the total Sc/Zr content increased, the formation of primary Al₃(Sc, Zr) phases could significantly refine the primary Al₁₁Ce₃ phases by acting as heterogeneous nucleation sites. Therefore, in 0.23 wt % Sc-0.16 wt % Zr and 0.49 wt % Sc-0.23 wt % Zr alloys, the modification effect on primary Al₁₁Ce₃ phases was based upon the interaction of adsorption effect and heterogeneous nucleation. The sizes of primary Al₁₁Ce₃ phases were refined to ∼37 μm and ∼32 μm, leading to a significant improvement in ultimate tensile strength (from ∼117 MPa to ∼182 MPa), yield strength (from ∼75 MPa to ∼145 MPa) and elongation (from ∼1.4% to ∼3.4%) in the 0.49 wt % Sc-0.23 wt % Zr alloy compared to the unmodified alloy. The Sc and Zr atoms that were dissolved in the matrix as a decomposed solid solution precipitated the L1₂-Al₃(Sc, Zr) phases after thermal exposure, which maintained full coherency with the Al matrix, leading to a hardness increase, rather than a decrease, after 300 °C and 400 °C thermal exposure. Therefore, Al–15Ce-(Sc–Zr) alloys open a new alloy system for engineering materials useable in high-temperature applications.

由于 Al ₁₁ Ce ₃相的高稳定性，Al-Ce 合金具有理想的高温性能。Al ₁₁ Ce ₃相的形貌和尺寸在决定 Al-Ce 合金的强化效果方面起着重要作用。本文研究了添加 Sc/Zr 对过共晶铸造 Al-Ce 合金的显微组织、力学性能和热稳定性的影响。结果表明，Sc和Zr原子可以吸附在Al ₁₁ Ce ₃相表面并控制0.13 wt % Sc-0.06 wt % Zr添加合金的生长过程，以及初生Al ₁₁ Ce ₃的尺寸。相从~79μm细化到~56μm。随着总Sc/Zr含量的增加，初生Al ₃ (Sc, Zr)相的形成可以作为异质形核位点显着细化初生Al ₁₁ Ce ₃相。因此，在0.23 wt % Sc-0.16 wt % Zr和0.49 wt % Sc-0.23 wt % Zr合金中，对初生Al ₁₁ Ce ₃相的改性作用是基于吸附作用和异相形核作用的相互作用。初生Al ₁₁ Ce ₃的尺寸相被细化到~37 μm和~32 μm，导致极限抗拉强度（从~117 MPa到~182 MPa）、屈服强度（从~75 MPa到~145 MPa）和伸长率（从~1.4与未改性合金相比，在 0.49 wt % Sc-0.23 wt % Zr 合金中的 % 至 ∼3.4%)。Sc 和 Zr 原子以分解固溶体的形式溶解在基体中，在热暴露后沉淀出 L1 ₂ -Al ₃ (Sc, Zr) 相，与 Al 基体保持完全共聚，导致硬度增加，而不是在 300 °C 和 400 °C 热暴露后下降。因此，Al-15Ce-(Sc-Zr) 合金为可用于高温应用的工程材料开辟了一种新的合金体系。