(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) 有色金屬材料科學(xué)與工程教育部重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 采用金相顯微鏡(OM)、透射電鏡(TEM)、慢應(yīng)變速率拉伸(SSRT)、雙懸臂梁實(shí)驗(yàn)(DCB)、晶間腐蝕實(shí)驗(yàn)和剝落腐蝕實(shí)驗(yàn)研究時(shí)效工藝對(duì)1933鋁合金鍛件抗應(yīng)力腐蝕(SCC)、抗晶間腐蝕(IGC)和抗剝落腐蝕(EC)性能的影響。結(jié)果表明：在T6(120 ℃，24 h)時(shí)效狀態(tài)下，1933鋁合金鍛件的應(yīng)力腐蝕敏感性最強(qiáng)，應(yīng)力腐蝕臨界應(yīng)力強(qiáng)度因子KISCC僅為8.95 MPa·m1/2。經(jīng)(110 ℃，6 h)+(160 ℃，8 h)和(110 ℃，12 h)+(170 ℃，8 h)雙級(jí)時(shí)效后，KISCC分別上升至23.84和27.56 MPa·m1/2，鍛件的抗應(yīng)力腐蝕性能顯著提高。而經(jīng)(110 ℃，12 h)+(180 ℃，6 h)時(shí)效后，抗應(yīng)力腐蝕性能的提高伴隨著較大幅度的強(qiáng)度損失和塑性損失。鍛件在各時(shí)效狀態(tài)下，晶間腐蝕形式為點(diǎn)蝕，具有良好的抗晶間腐蝕性能。同時(shí)，鍛件具有良好的抗剝落腐蝕性能。T6時(shí)效時(shí)，鍛件的剝蝕等級(jí)為EC級(jí)；經(jīng)雙級(jí)時(shí)效后，其剝蝕等級(jí)均在EA+級(jí)以上。
關(guān)鍵字: 1933鋁合金，鍛件；抗應(yīng)力腐蝕性能；抗晶間腐蝕性能；抗剝落腐蝕性能
1933 aluminum alloy forging
（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 effects of aging treatment on the stress corrosion cracking resistance, intergranular corrosion (EC) resistance and exfoliation corrosion resistance of 1933 aluminum alloy forging were investigated by means of optimal microscopy (OM), transmission electron microscopy (TEM), slow strain rate testing (SSRT), double-cantilever-beam (DCB) experiment, intergranular corrosion (IGC) and EC experiments. The results show that the 1933 aluminum alloy forging under T6(120 ℃, 24 h) aging treatment reveals the strongest stress corrosion cracking sensitivity and the critical stress intensity factor KISCC is only 8.95 MPa·m1/2. After aging treatment at (110 ℃, 6 h)+(160 ℃, 8 h) and (110 ℃, 12 H)+(170 ℃, 8 h), KISCC is elevated to 23.84 and 27.56 MPa·m1/2, respectively, which indicates higher stress corrosion cracking resistance. Accompanying the improvement of stress corrosion resistance, the strength loss and plasticity loss decrease sharply when the forging is aging-treated at (110 ℃, 12 h)+(180 ℃, 6 h). The forging has excellent intergranular corrosion resistance under all aging treatments and the forms of corrosion are all pit corrosion. Meanwhile, the exfoliation corrosion resistance of the forging is also very good. The level of exfoliation corrosion is EC when the forging is under T6 aging treatment. After duplex aging, the level of exfoliation corrosion for the forging is EA+.
Key words: 1933 aluminum alloy; forging; stress corrosion cracking resistance; intergranular corrosion resistance; exfoliation corrosion resistance
