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对ＬＹ１２ＣＺ铝合金板件单向拉伸状态下表面塑性损伤的细观演变过程进行了定量、定性对比观测，并选用和定义了表面损伤变量ＤＡ、Ｄ（Ｌ）和Ｄ（Ｒａ），以及整体损伤变量Ｄ（Ｅ），对材料表面的损伤演变规律进行了描述，并与材料整体的损伤进行了比较。结果表明：表面塑性损伤的细观机理与材料内部的基本一致，是微空穴的形核、长大与汇合为宏观裂纹的过程，汇合方向只与外载的方向有关；三表面损伤变量中，Ｄ（Ａ） 、Ｄ（Ｒａ）随ε的增大呈幂函数增大，Ｄ（Ｌ）则是先平稳变化，最后迅速增大；三变量间互相关，且Ｄ（Ｌ）较Ｄ（Ａ）对材料损伤变化更为敏感；表面损伤较整体损伤的变化稍有滞后。
The microscopic evolution process of plastic damage of the surface of LY12CZ aluminum alloy sheet under uniaxial tension was quantitatively and qualitatively compared. The surface damage variables DA, D (L) and D (Ra ), As well as the overall damage variable D (E), the damage evolution of the material surface was described and compared with the overall damage of the material. The results show that the mesoscopic mechanism of surface plastic damage is basically the same as that of the material, which is the process of nucleation, growth and confluence of microcavities. The confluence direction is only related to the direction of external load. Among the three surface damage variables , D (A) and D (Ra) increased with the increase of ε as a power function, while D (L) first changed smoothly and finally rapidly increased. The three variables were cross-correlated and D ) is more sensitive to changes of material damage than D (A); the damage of the surface is slightly delayed than that of the whole injury.