将304不锈钢在620℃的Al-12Si-xCu(x分别为0，5，10，15，质量分数/%)合金熔体中腐蚀120h，研究了铜含量对不锈钢腐蚀行为的影响及其机理.结果表明:随铜含量的增加，304不锈钢的腐蚀速率和腐蚀层厚度减小；表面腐蚀层可分为内腐蚀层和外腐蚀层，外腐蚀层的显微硬度随铜含量的增加而增大，而内腐蚀层的硬度则降低；腐蚀反应主要在不锈钢中的铁、铬原子和合金熔体中的铝、硅原子之间进行，铜原子没有参与腐蚀反应，但铜的添加降低了腐蚀产物生长常数，从而降低了合金熔体的腐蚀能力.

304 stainless steel was corroded in Al-12Si-xCu (x=0, 5, 10, 15, mass fraction/%) alloy melts at 620℃ for 120 h. The effect and mechanism of Cu content on corrosion behavior of the stainless steel were studied. The results show that the corrosion rate and the corrosion layer thickness of 304 stainless steel decreased with the increase of Cu content. The surface corrosion layer was composed of inner corrosion layer and outer corrosion layer. The microhardness of outer corrosion layer increased and that of inner corrosion layer decreased with the increase of Cu content. The corrosion reaction mainly occurred between Fe, Cr atoms in the stainless steel and Al, Si atoms in the alloy melt. Cu atom was not involved in the corrosion reaction. However, the addition of Cu reduced the diffusion activation energy of corrosion reaction, resulting in the decrease of corrosion ability of the alloy melt.