(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083；
2. 中南大學(xué) 教育部有色金屬材料科學(xué)與工程實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 采用透射電鏡觀察、硬度和電導(dǎo)率測(cè)試等手段研究雙級(jí)時(shí)效對(duì)1973高強(qiáng)高韌鋁合金組織和性能的影響。結(jié)果表明：一級(jí)時(shí)效溫度對(duì)合金最終組織和性能的影響不大，二級(jí)時(shí)效溫度和時(shí)間對(duì)1973鋁合金硬度和電導(dǎo)率的影響明顯；1973鋁合金適宜的雙級(jí)時(shí)效工藝為(120 ℃, 6 h)＋(160 ℃, 16 h)，在此條件下，合金的硬度和電導(dǎo)率分別為191HV和38.0%(IACS)，其顯微組織特點(diǎn)為晶內(nèi)沉淀相呈細(xì)小彌散狀分布，而合金的晶界沉淀相粗大、呈斷續(xù)狀分布，并且有較明顯的無沉淀析出帶。合金中主要沉淀相為η'相和η相，此外還有少量的GPⅡ區(qū)。
關(guān)鍵字: 1973鋁合金；雙級(jí)時(shí)效；電導(dǎo)率；沉淀析出
properties of 1973 aluminum alloy
（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 two-stage ageing on the microstructures and properties of 1973 aluminum alloy were studied by means of transmission electron microscopy (TEM), hardness and conductivity measurements. The results show that the temperature and time of the second-stage ageing have a key effect on the properties of the alloy, while the temperature of the first-stage ageing has little effect on them. The best two-stage ageing process for this alloy is: (120 ℃, 6 h)＋(160 ℃, 16 h). Under this condition, the hardness and electrical conductivity of this alloy are 191HV and 38.0%(IACS), respectively. The microstructure of this alloy is that the nano scale precipitates disperse inside the grain, and the coarse-discontinuous precipitates occur along the grain boundaries. The precipitated-free zones (PFZ) appear on the grain boundaries. The main precipitates are η and η' phases, and with minous GPⅡ zone.
Key words: 1973 aluminum alloy; two-stage ageing; conductivity; precipitation
