【摘要】 研究了时效工艺对Al-Zn-Mg-Cu挤压棒材组织和性能的影响。结果表明，合金经双级+再时效、回归再时效和非等温时效处理后，均获得了优于T73时效处理的抗晶间腐蚀性能，最大腐蚀深度由70μm分别降至19、48和30μm。合金经过双级+再时效处理后，获得了与回归再时效和非等温时效处理样品相近的抗拉强度和屈服强度，而抗晶间腐蚀性能明显优于回归再时效和非等温时效。合金经T73、双级+再时效、回归再时效和非等温时效处理后，晶界析出相平均尺寸分别为27.7、39.2、31.6和25.5 nm,基体沉淀相平均尺寸分别为8.1、10.2、10.9和11.0 nm。更多还原

【Abstract】 The effects of aging treatment on the microstructure and properties of Al-Zn-Mg-Cu extruded bars were investigated. The results show that the alloys treated by two-stage aging and re-aging(TSR), retroregression and re-aging(RRA), and non-isothermal aging(NIA), compared to the treatment with T73, all present better intergranular corrosion(IGC) resistance, with the maximum corrosion depth down from 70 μm to 19, 48, and 30 μm, respectively. Compared to those treated by RRA and NIA, the TSR-treated alloy has the similar tensile strength and yield strength, but obviously superior IGC. After the treatment of T73, TSR, RRA, and NIA, the alloy has its grain boundary precipitates with average size of 27.7, 39.2, 31.6, and 25.5 nm, respectively, and matrix precipitates with average size of 8.1, 10.2, 10.9, and 11.0 nm, respectively.更多还原