时效工艺对2297铝锂合金组织与力学性能的影响  

Effect of aging process on microstructure and mechanical properties of 2297 Al-Li alloy

作　　者：范雪松[1] 郑子樵[1] 陈向荣[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《粉末冶金材料科学与工程》2017年第2期184-189,共6页Materials Science and Engineering of Powder Metallurgy

基　　金：国家高技术研究发展计划(863计划)资助项目(2013AA032401)

摘　　要：对热轧态2297铝锂合金进行530℃/1 h固溶处理后立即水淬,然后在不同温度(150~180℃)和时间(0~160h)条件下进行时效热处理,利用透射电镜观察合金的微观组织,并测定合金的抗拉强度(σb)、屈服强度(σ0.2)和伸长率(δ),研究时效温度与时间对2297铝锂合金组织与性能的影响。结果表明:合金的强度随时效时间延长而升高,达到峰值后趋于稳定。随时效温度升高,合金强度达到峰值的时间逐渐缩短,峰值强度先升高后降低,塑性则随时效时间延长或时效温度升高而逐渐下降。时效温度为160℃时,时效初期合金的主要析出相为δ′相,峰时效态合金是T_1相、θ′相和δ′相共同强化,过时效态合金的主要析出相为T_1相。时效温度为180℃时,合金的主要析出相为T_1相,θ′相和δ′相的数量非常少。The hot rolled 2297 A1-Li alloy was aged at different temperature （150-180 ℃） and time （0-160 h） after solid solution treatment for 530 ℃/1 h. The microstructure of the alloy was observed by TEM, and the tensile strength （ab）, yield strength （a0.2） and elongation （d） of the alloy were measured by the tensile test. The effects of aging temperature and time on the microstructure and tensile properties of 2297 A1-Li alloy were investigated. The results show that the tensile strength increases and can reach the peak value with increasing aging time, but doesn＇t decrease at over-aged condition. The higher the aging temperature is, the shorter the time for reaching the peak value. With increasing aging temperature, the peak value of aged alloy increases first and then decreases. The tensile elongation decreases with increasing aging temperature or time. The main precipitates detected in trader-aged alloy is phase when aging at 160 ℃, and the microstructure of peak-aged alloy consists of Tl, 0＇ and phases, while the main precipitate of over-aged alloy is TI phase. The alloy aged at 180 ℃ mainly contains T1 phase, while the precipitation of 0＇ and 6＇ phases is limited.

关 键 词：2297合金 时效 温度 力学性能 微观组织 

分 类 号：TG146.21[一般工业技术—材料科学与工程]