(中南大學 有色金屬材料科學與工程教育部重點實驗室，湖南 長沙 410083)
摘 要: 通過顯微硬度測試、拉伸實驗、DSC分析和TEM觀察，研究微量Ag的添加對6022汽車車身板成形性能、模擬烤漆后的力學性能、時效動力學和微觀組織的影響。結果表明：在6022合金中添加0.35%(質(zhì)量分數(shù))Ag，可以顯著提高6022合金175 ℃時效30 min后的強度，提高時效響應速度和峰值硬度，但對T4態(tài)下成形性能的影響較小；Ag的加入對時效過程的影響是通過促進GP區(qū)的形成，進而為β″相的析出提供更多的形核位置，從而促進主要強化相β″相的析出。
關鍵字: 6022鋁合金；汽車車身板；Ag；成形性能；模擬烤漆
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
