This paper presents the influence of aging temperature and time on microstructure and mechanical properties of 7003 aluminum alloy by hardness tester,transmission electron microscope and tensile testing machine. The results show that the GP zone、η′(metastable phase MgZn2) and η(stable equilibrium phase MgZn2) are precipitated gradually from the 7003 aluminium alloy with the extension of aging time. Both of GP zone and η′phase can hinder the movement of dislocations, they played a significant role in strengthening the alloy. With the number of GP area is growing to the maximum,the strength is reached the first peak. The strength is reached the second peak after the GP zone generated to η′. When the η′ is generated to η, the strength are decreased. With the increase of aging temperature,both the time of the two peaks and the interval between them are shortened evidently. When the aging temperature is 120℃, he intensity of the second peak is higher than that of the first peak,while the intensity of the second peak is lower than the first peak at the temperature of above 120℃.%采用透射电镜、维氏硬度仪和拉伸试验机,研究了时效温度和时间对7003铝合金显微组织与力学性能的影响.结果表明,随着时效时间的延长,铝合金基体中依次沉淀析出GP区、η′相(亚稳定相MgZn2)和η相(MgZn2),其中GP区和η′相都能阻碍位错运动,对铝合金起到很好的强化作用.当GP区数量最多时,铝合金的强度达到第一个峰值;当GP区转变为过渡相η′时,铝合金的强度达到第二峰值;当η′转变为η相时,铝合金的强度开始下降.随着时效温度的提高,铝合金强度达到峰值的时间缩短,并且两个峰值之间的时间间隔也缩短.时效温度为120℃时,铝合金的第二峰值强度高于第一峰值强度;时效温度高于120℃时,铝合金的第一峰值强度高于第二峰值强度.
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