利用透射电子显微术研究了7075铝合金在T6,CgS3和T73状态的微观组织,并讨论了组织结构与强度和应力腐蚀抗力(SCR)的关系.结果表明,影响合金性能的主要因素是基体析出相(MPt)的密度、尺寸和类型,在CgS3状态,MPt主要为η′过渡相,其密度约5×10~(16)/cm~3,尺寸5—7nm,合金的强度和SCR综合性能较佳.作者认为这应归因于位错绕过η′粒子的几率增大. The microstructure of 7075 aluminum alloy in T6, CgS3 and T73 states was investigated by transmission electron microscopy, and the relationship between microstructure and strength and stress corrosion resistance (SCR) was discussed.The results show that the main factors affecting the performance of the alloy are matrix The density, size and type of precipitated phase (MPt) are mainly η ’transition phase in CgS3 state. The density of MPt is about 5 × 10-16 / cm 3 and the size is 5-7 nm. The authors believe this should be attributed to the increased chance of dislocations bypassing η ’particles.