Abstract The anti-phase boundaries (APBs) in the T (Al20Cu2Mn3) phase and the interfaces of the T phase with an Al matrix were observed. The effects of pre-deformation on the precipitation behavior of T phase and hardening behavior of alloy were investigated by hardness measurement, mechanical tensile test, transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Results show that two kinds of APBs exist in the T phase, i.e. {101}T and {301}T-type APBs. The first is commonly observed, while the latter is newly found and only coexists with the first to form a zig-zag shaped APB. Whatever its orientation relationships (ORs) with Al matrix and cross-section (CS) shape, the T phase always retains its interfaces constituted by {200}T, {101}T and {301}T planes. Pre-deformation increases the APBs in T phase and intensifies the irregularity of the CS shape of a T phase. Besides, it also promotes the nucleation and refines the size of the T phase during precipitation which enhances the mechanical properties of the alloy.

中文翻译：

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T(Al20Cu2Mn3)相中新型反相界及预变形对T相析出的影响

摘要 观察了T (Al20Cu2Mn3) 相中的反相界(APBs) 以及T 相与Al 基体的界面。通过硬度测量、机械拉伸试验、透射电子显微镜（TEM）和高分辨率透射电子显微镜（HRTEM）研究了预变形对T相析出行为和合金硬化行为的影响。结果表明T相中存在两种APBs，即{101}T型和{301}T型APBs。通常观察到第一种，而后者是新发现的，仅与第一种共存形成锯齿形 APB。无论其与 Al 基体的取向关系 (OR) 和横截面 (CS) 形状如何，T 相始终保留其由 {200}T、{101}T 和 {301}T 平面构成的界面。预变形增加了 T 相中的 APB，并加剧了 T 相 CS 形状的不规则性。此外，它还促进了析出过程中T相的形核并细化了T相的尺寸，从而提高了合金的力学性能。