采用磁控溅射方法在不锈钢表面制备了铜原子分数在0~11.8%的Al-Cu合金薄膜，研究了铜含量对薄膜微观结构、纳米压痕力学性能和强化机制的影响。结果表明：纯铝薄膜呈现面心立方结构，铜原子分数在2.2%~6.5%时Al-Cu合金薄膜均形成过饱和固溶体相，当铜原子分数超过6.5%后，薄膜中生成了AlCu化合物。随铜含量的增加，薄膜的晶粒尺寸减小，硬度和弹性模量增加，当铜原子分数增至11.8%时，晶粒尺寸为34.7 nm，硬度和弹性模量分别比纯铝薄膜提高了212.5%，2.2%；当铜原子分数在0~6.5%时薄膜的强化主要来自于细晶强化和固溶强化，当铜原子分数超过6.5%后，薄膜的强化是细晶强化、固溶强化和第二相强化共同作用的结果。

Al-Cu alloy films with copper atomic fractions of 0-11.8% were prepared on stainless steel by magnetron sputtering method. The effects of copper content on the microstructure, nanoindentation mechanical properties and strengthening mechanism of the films were investigated. The results show that the pure aluminum film had a face-centered cubic structure. When the copper atomic fraction was between 2.2% and 6.5%, supersaturated solid solution phases were formed in Al-Cu alloy films. When the copper atomic fraction exceeded 6.5%, AlCu compounds were formed in films. With the increase of copper content, the grain size of the film decreased, and the hardness and elastic modulus increased. When the copper atomic fraction increased to 11.8%, the grain size was 34.7 nm, and the hardness and elastic modulus increased by 212.5% and 2.2% those of the pure aluminum film, respectively. When the copper atomic fraction was between 0 and 6.5%, the strengthening of films mainly depended on grain refinement strengthening and solid solution strengthening. When the copper atomic fraction exceeded 6.5%, the strengthening of films was determined by the combination of grain refinement strengthening, solid solution strengthening and second phase strengthening.