Introduction of 0.3% Cr into Al–Cu–Er–Zr alloy leads to significant modification of the grain structure and almost complete elimination of a dendritic structure. The average grain size of 40 μm corresponds to the size of a dendritic cell. The good modifying capacity is explained by formation of intermetallic compounds of the phase first identified of approximate composition Al_75–80Cu_10–12Er_3–4Cr₇, which is a substrate for nucleation of primary aluminum. After quenching and aging, slight hardening in the alloy is achieved due to L1₂ –Al₃(Zr,Er) dispersoids with an average diameter of 40 nm and q’(Al₂Cu) precipitates with a diameter up to 100 nm and a thickness up to 5 nm. No particles containing chromium are found within the matrix. According to thermodynamic calculations, hot rolling of AlCuErZrCr alloy at a temperature of 440°C should proceed in the ((Al)+Al₃Zr+Al₇Cr) phase region. However, analysis of the fine structure in an annealed condition after rolling showed presence of only L1₂ –Al₃(Zr,Er) dispersoids. Differences in alloy hardness on annealing up to 300°C may be explained either by the influence of dissolved chromium atoms or by formation of chromium-containing particle clusters, which could not be detected.

在 Al-Cu-Er-Zr 合金中引入 0.3% Cr 可显着改变晶粒结构，几乎完全消除枝晶结构。40μm的平均晶粒尺寸对应于树突状细胞的尺寸。_{良好的改性能力是通过首先确定的近似成分 Al 75–80} Cu _10–12 Er _3–4 Cr ₇的相的金属间化合物的形成来解释的，该相是原铝成核的基质。淬火和时效后，由于平均直径为 40 nm 的L1 ₂ –Al ₃ (Zr,Er) 弥散体和直径高达 100 nm 的q'(Al ₂ Cu) 析出物，合金实现了轻微硬化。厚度可达5纳米。基体中未发现含有铬的颗粒。根据热力学计算，AlCuErZrCr合金在440℃的温度下热轧应在((Al)+Al ₃ Zr+Al ₇ Cr)相区进行。然而，轧制后退火条件下的精细结构分析表明仅存在 L1 ₂ –Al ₃ (Zr,Er) 弥散体。退火至 300°C 时合金硬度的差异可能是由于溶解的铬原子的影响或由于无法检测到的含铬颗粒簇的形成而造成的。