(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院,長沙 410083;
2. 中南大學(xué) 教育部有色金屬材料科學(xué)與工程實驗室,長沙 410083)
摘 要: 采用硬度測試、晶間腐蝕試驗、金相及透射電鏡觀察研究人工時效對6005A鋁合金晶間腐蝕性能的影響。結(jié)果表明:6005A鋁合金在固溶水淬后進行人工時效,晶間腐蝕敏感性隨時效時間的延長而變化;時效初期,合金的晶間腐蝕敏感性很低,隨時效時間的延長,晶間腐蝕敏感性增加;時效12 h時,合金硬度達峰值,同時晶間腐蝕敏感性也達最大,隨后晶間腐蝕敏感性減弱,出現(xiàn)點蝕。6005A鋁合金晶間腐蝕敏感性與晶界有關(guān),點蝕的引入與晶內(nèi)Q′相的析出長大有關(guān)。
關(guān)鍵字: 6005A鋁合金;人工時效;晶間腐蝕
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410083, China)
Abstract:The effect of artificial ageing on the corrosion performance of 6005A Al alloy was investigated by hardness test, intergranular corrosion test, optical microscopy and TEM observation. The results show that the intergranular corrosion susceptibility of 6005A Al alloy is related to the artificial ageing time. The accelerated corrosion test reveals that the intergranular corrosion(IGC) of 6005A Al alloy is low susceptible to in the beginning of the artificial ageing after water quenched. However, IGC susceptibility increases with the increase of aging time, and reaches the peak value after artificial ageing for 12 h, while the hardness is the highest. The overageing reduces the IGC susceptibility, however, the slight pitting is produced. The increased IGC susceptibility is related to the grain boundary. The pitting susceptibility by over ageing is evolved due to coarsening of the Q′-phase particles.
Key words: 6005A Al alloy; artificial ageing; intergranular corrosion


