(河海大學(xué) 力學(xué)與材料學(xué)院， 南京 210098)
摘 要: 采用全浸泡腐蝕和電化學(xué)腐蝕研究等徑角擠壓制備的超細(xì)晶鋁銅合金塊材在氯化鈉溶液中的腐蝕行為。結(jié)果表明：超細(xì)晶鋁銅合金中基體相α(Al)晶粒細(xì)小(為200~300 nm)；鑄態(tài)組織中網(wǎng)狀θ相(Al2Cu)破碎、細(xì)化成10 μm左右的顆粒并均勻分布于形變?chǔ)?Al)基體上；形變細(xì)化提高鋁銅合金在氯化鈉介質(zhì)中的耐蝕性能，表現(xiàn)出全浸泡腐蝕中更輕的腐蝕程度、電化學(xué)測試中更大的極化電阻、更正的自腐蝕電位和點(diǎn)蝕電位、更小的腐蝕電流密度。
關(guān)鍵字: Al-Cu合金；等徑角擠壓；超細(xì)晶；腐蝕行為
fabricated by equal-channel angular pressing
（College of Mechanics and Materials, Hohai University, Nanjing 210098, China）
Abstract:The effect of strain-induced grain refinement on the corrosion behavior of ultra-fine grain bulk Al-5%Cu alloy fabricated by equal-channel angular pressing (ECAP) was investigated by constant immersion tests and electrochemical corrosion in NaCl solution. The results show that the ECAP Al-Cu alloy obtains a finer grain size (200−300 nm) of α(Al) matrix, and the original net-like coarse θ phase is also broken into uniformly distributed fine particles with grain size of about 10 μm. The corrosion resistance of ultra-fine grain (UFG) Al-Cu alloy is obviously improved with alleviated corrosion damaged morphologies in constant immersion test, and the alloy has more positive open circuit potential (φ0), higher fitted Rt values, more positive self corrosion potential (φp) and lower corrosion current (Jc) values in electrochemical measurements.
Key words: Al-Cu alloy; equal-channel angular pressing; ultra-fine grain; corrosion behavior
