(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083；
2. 有色金屬材料科學(xué)與工程教育部重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410012)
摘 要:
關(guān)鍵字: 7050鋁合金；末端淬火；淬火敏感性
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Materials Science and Engineering, Ministry of Education, Changsha 410012, China）
Abstract:The quenching sensitivity of 7050 aluminium alloy hot-rolled plate was studied by using end quenching test and optical microscopy (OM) and transmission electron microscopy (TEM). It is showed that, the distance from the quenching end where hardness decreases by 10% is about 60 mm. The reducing of mechanical properties is mainly caused by precipitation of equilibrium η phase. The critical average quenching cooling rate for precipitation of η phase is about 40 ℃/s, at which the volume fraction of η phase is about 2.1%. When the critical average quenching cooling rate is lower than 40 ℃/s, three processes of formation and growth of η phase—recrystallization—formation of incoherent Al3Zr dispersoid happen.
Key words: 7050 aluminium alloy; end quenching; quenching sensitivity
