铝镁硅合金自然时效的析出强化组织及性能  

Effect of Precipitation Strengthening during Natural Aging in Al-Mg-Si Alloy

作　　者：钟沐春 姜锋[1] 黄宏锋[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《航空材料学报》2015年第5期39-45,共7页Journal of Aeronautical Materials

摘　　要：通过力学性能、硬度、电导率和X-Ray测试,结合透射电子显微镜以及高分辨透射电镜观察,系统研究了AlMg-Si合金中,NA(NA)及NA对后续200℃/2h AA(AA)产生的组织与性能的影响。结果表明:NA脱溶组织在后续热处理中对合金强度、硬度提高存在有利影响。NA(8h)+AA比固溶淬火后直接进行AA态析出的强化相数量更多、尺寸更小、弥散度更高;NA(0h)+AA在固溶淬火后溶质原子充足、原子扩散的驱动力强,析出相尺寸更大;而NA(8h)能析出弥散的原子团簇,有效地成为AA析出相形核中心,生成更多强化效果最佳的β″相。合金最适宜的工艺为NA(8h)+AA(200℃/2h)。In order to investigate the effect of natural aging（ for different storage time） and subsequent artificial aging in 200℃ /2h on microstructure and property of Al-Mg-Si alloys,TEM,HRTEM,X-Ray analysis and tensile strength,hardness,electrical conductivity measurements were taken. It reveals that natural aging does a favor to alloy strength and hardness for the sake of precipitation influences. Moreover,natural aging（ 8h） ＋ artificial aging is better than traditional artificial aging,as the former method could groduce smaller size,more separated precipitations. Without natural aging,the α（ Al） matrix has sufficient Mg,Si solute atoms,so it could precipitate larger precipitation particles. While during 8h natural aging,some atom clusters precipitate from the α（ Al） matrix,which could be the center of precipitation and finally generate more strengthening precipitation β″ phase. As a result,the best heat treatment is natural aging（ 8h） ＋ artificial aging（ 200℃ /2h）.

关 键 词：AL-MG-SI合金 NA 析出相 强化 

分 类 号：TG146.21[一般工业技术—材料科学与工程]