单级时效7056铝合金的显微组织与性能  

Microstructure and Properties of Single-aging 7056 Aluminum Alloy

作　　者：蒋建辉[1] 郑子樵[1] 唐娟[1] 李世晨[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《机械工程材料》2013年第4期69-74,共6页Materials For Mechanical Engineering

摘　　要：通过维氏硬度和电导率测试以及透射电镜观察,研究了7056铝合金在105,120,135,150℃单级时效后的硬度、电导率及显微组织。结果表明:7056铝合金有着极快的时效响应速度,在不同温度下时效1h后,其硬度升至188～206HV,已达到合金峰值硬度的86.9%以上;在4种单级时效温度下,合金峰时效的析出相都是以η′相为主,时效温度的变化并没有引起峰值硬度的明显变化,但会显著加快时效的析出过程;7056铝合金在105℃时效的组织演变为GPⅠ区+η′(少量)→η′+GPⅠ区(少量)→η′;在120℃时为GPⅠ区+η′+GPⅡ区(少量)→η+GPⅡ区(少量)→η′+GPⅡ区(少量);在135℃时为η′+GPⅡ区→η′+GPⅡ区(少量)→η′;在150℃时为η′+GPⅡ区(少量)→η′+GPⅡ区(少量)→η+η′(少量)。The hardness, conductivity and microstructure of 7056 aluminum alloys during single-aging treatments at 105,120,13,150 ℃were investigated by using Vickers, conductivity measurement and transmission electron microscopy （TEM）. The results show that the aging response speed of 7056 aluminum alloys was very rapid, the hardness can rose to 188--206 HV for 1 h aging, which was more than 86. 9% of the peak-aging hardness. Under the four single-aging temperatures, the major precipitates of this alloy in the peak-aging were all η＇ phase. The altering of aging,temperature make no remarkable changes of the peak-aging hardness in the alloy, but can significantly accelerate the aging separation process. The microstructure evolution processes of 7056 aluminum alloy during the four single-aging treatments were described as follows： 105 ℃ aging sequence was GP I zone→η＇（a few）→η＇ ＋GP I zone （a few）→η＇ ; 120 ℃aging sequence was GP I zone→η＇ ＋GP II zone （a few）→η＇ ＋GP II zone （a few）→η＇＋GP]I zone （a few） ; 135 ℃ aging sequence was r/＋GP 1] zone→η＇ ＋GP ]l zone （a few）→η＇; 150 ℃ aging sequence was η＇＋GPll zone （a few）→η＇＋GP]] zone （a few）→η＋η＇（a few）.

关 键 词：7056铝合金 单级时效 维氏硬度 电导率 显微组织 

分 类 号：TG146.21[一般工业技术—材料科学与工程]