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以２０２４Ａｌ合金为对象，采用连续加载法，详细研究了在各种热处理状态下该材料的微屈服行为。研究结果表明，在其连续拉伸过程中存在弹性、微屈服及宏观屈服３个阶段；微屈服阶段的硬化率远高于初期宏观屈服阶段的硬化率，表明微屈服与宏观屈服的位错运动机制有差异。其微屈服阶段的σ—ε１／２ｐ曲线有两种不同类型：（ａ）直线型及（ｂ）转折型，其中（ａ）型符合经典的ＢｒｏｗｎＬｕｋｅｎｓ关系；而（ｂ）型则不符合ＢＬ关系，这与热处理造成的不同微结构有关。热处理对该材料的微屈服强度有很大影响，固溶强化、时效第二相沉淀强化及多次热循环的位错亚结构多边化均能明显提高该合金的微屈服强度。
Taking 2024Al alloy as an example, the micro-yield behavior of the material under various heat treatment conditions was studied in detail by continuous loading method. The results show that there are three stages of elasticity, micro-yielding and macro-yielding during the continuous drawing process. The micro-yielding hardening rate is much higher than that of the initial macro-yielding stage, indicating that the micro-yielding and macro-yielding dislocation motions Mechanism is different. There are two different types of sigma-ε1 / 2p curves in the micro-yield stage: (a) linear and (b) transitional types, where (a) corresponds to the classical Brown-Lukens relationship; B L relationship, which is caused by the heat treatment of different microstructures. Heat treatment has a great influence on the micro-yield strength of the material. The solid solution strengthening, the precipitation strengthening of the second phase and the multilateral dislocation sub-structure of multiple thermal cycles can significantly improve the micro-yield strength of the alloy.