(中南大学 有色金属材料科学与工程教育部重点实验室，湖南 长沙 410083)
摘 要: 通过显微硬度测试、拉伸实验、DSC分析和TEM观察，研究微量Ag的添加对6022汽车车身板成形性能、模拟烤漆后的力学性能、时效动力学和微观组织的影响。结果表明：在6022合金中添加0.35%(质量分数)Ag，可以显著提高6022合金175 ℃时效30 min后的强度，提高时效响应速度和峰值硬度，但对T4态下成形性能的影响较小；Ag的加入对时效过程的影响是通过促进GP区的形成，进而为β″相的析出提供更多的形核位置，从而促进主要强化相β″相的析出。
关键字: 6022铝合金；汽车车身板；Ag；成形性能；模拟烤漆
6022 aluminum alloy for automotive body sheets
（Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410083,China）
Abstract:The effect of Ag on the formability, paint-bake tensile properties, aging dynamics and microstructures of 6022 aluminum alloy for automotive body sheets were studied by hardness tests, tensile tests, differential scanning calorimetry(DSC) and transmission electron microscopy(TEM). The results show that the formability of 6022 alloy containing 0.35% (mass fraction) Ag in T4 condition is declined a little, and after 30 min paint-bake aging at 175 ℃, higher strength can be obtained. Ag addition can also improve the aging response and hardness, and promote the precipitation of the β″ phase which should prefer to nucleate on the position of GP zones.
Key words: 6022 aluminum alloy; automotive body sheets; Ag; formability; paint-bake aging
