2519铝合金时效过程的组织特征  

Microstructure Characteristics of Aged 2519 Aluminum Alloy

作　　者：李慧中[1] 张新明[1] 陈明安[1] 周卓平[1] 龚敏如[1] 

机构地区：[1]中南大学

出　　处：《特种铸造及有色合金》2005年第5期273-275,共3页Special Casting & Nonferrous Alloys

基　　金：国家"973"重点基础研究发展规划项目 (G1 9990 6490 8)

摘　　要：采用金相、透射电镜、扫描电镜、硬度测试等手段,研究了2 5 1 9铝合金在1 80℃时效组织与性能的变化。结果表明,2 5 1 9铝合金在1 80℃时效时具有3阶段时效特征:①时效5h ,合金沿晶界析出少量不连续的θ(或θ′)相,晶内未见明显的析出物;②峰值时效,合金晶内普遍析出强化相θ″相,晶界析出θ(或θ′)相呈链状连续分布;③时效2 0h ,晶界析出θ(或θ′)相粗化、球化并且呈离散分布,晶内析出θ′相变粗。随着时效时间的延长,合金的伸长率逐渐降低。Microstructure and properties of 2519 alloy during aging process at 180 ℃ were researched by means of optical microscopy (OM),transmission electron microscopy(TEM),scanning electron microscopy (SEM) and hardness test.The results showed that three aged stages are observed during the aging process of 2519 aluminum alloy at 180 ℃.The peak-aged time is 12 h.As the alloy for 5 h aging,a little amounts of discrete θ(or θ′) phase were precipitated from the grain boundaries,while no obvious precipitated phase in grain is found.Continuous chain-like θ(or θ′) phase precipitates were found on the grain boundaries and θ″ strength phase was commonly precipitated from the grain at peak-aged state.θ(or θ′) phase precipitates on the grain boundaries become coarse and spheroidization in a discrete state at aging for 20h,meanwhile the θ′ phase precipitated from the grain become coarse too.The elongation of the alloy was decreased with the increase of the aged time.

关 键 词：2519铝合金 时效 显微组织 力学性能 

分 类 号：TG156.9[金属学及工艺—热处理]