In order to study the effect of aging treatment on microstructure, mechanical properties and corrosion properties of Al-7.8Zn-1.6Mg-1.8Cu-0.12Zr aluminum alloy plate, which was rolled with ultrasonic casting ingot,the T6,T73,RRA aging treatment were adopted,and compared with the plate rolled with normal casting ingot. The results show that compared with T6 aging treatment the alloy under T73 aging treatment gets excellent corrosion resistance at the expense of strength. Under the condition of RRA aging treatment the alloy gets excellent corrosion resistance ability and still keep the strength as strong as under T6 aging treatment for the Al-7.8Zn-1.6Mg-1.8Cu- 0.12Zr aluminum alloy casting with ultrasonic introduced. Compared with the alloy without melt ultrasonic treatment,both the solid solubility of alloying elements in the ingot and vacancy density of the matrix of the alloy casting with ultrasonic treatment increase due to the cavitation, acoustic streaming and vibration effects brought by ultrasonic. The precipitates distributed uniformly and the part of them coarsened. The uniform distribution of tiny precipitates has a positive impact on the strength of the alloy, the coarsened precipitates do a negative effect on the strength, but it can improve the corrosion resistance of the alloys under the same aging treatment.%分别采用T6、T73和RRA 3种时效制度对超声铸造Al-7.8Zn-1.6Mg-1.8Cu-0.12Zr铝合金热轧板进行时效处理，研究时效制度对材料的组织、力学性能与耐腐蚀性能的影响，并与未经超声熔体处理的合金热轧板进行对比。结果表明：对于超声铸造Al-7.8Zn-1.6Mg-1.8Cu-0.12Zr铝合金的热轧板，与T6时效态合金相比，T73时效态合金的抗腐蚀性能较好，但强度显著降低，RRA状态的合金强度与T6态合金相当，抗腐蚀性能显著提高；相对于未经超声熔体处理的合金，在超声波的空化、声流和机械振动效应的作用下，铸态合金的合金元素固溶度以及基体空位浓度都增加，在其组织遗传效应的影响下，采用相同时效工艺处理后合金中析出相的分布更加均匀但出现部分粗化现象，均匀分布的细小析出相对合金的强度有积极影响，粗化的析出相对合金的强度不利，但能提高合金的耐腐蚀性能。
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