(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083； 2. 云南冶金集團(tuán)服份有限公司，昆明 650502； 3. 中南大學(xué) 輕合金研究院，長(zhǎng)沙 410083； 4. 中南大學(xué) 高性能復(fù)雜制造國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 基于實(shí)驗(yàn)室自制蛇形軋制裝置，采用室溫拉伸、Kahn撕裂、電子背散射衍射(EBSD)等測(cè)試方法對(duì)比研究蛇形軋制非對(duì)稱工藝參數(shù)對(duì)Al-Cu-Mg合金軋制板材的室溫強(qiáng)度、斷裂韌性和顯微組織的影響。結(jié)果表明：合理的蛇形軋制工藝在能夠使Al-Cu-Mg合金板材保持強(qiáng)度性能的同時(shí)，顯著提升其斷裂韌性。當(dāng)偏移量相同時(shí)，蛇形軋制板材的強(qiáng)度性能隨著異速比增加而提高，但伸長(zhǎng)率和斷裂韌性降低；當(dāng)異速比相同時(shí)，隨著偏移量增加，蛇形軋制板材強(qiáng)度降低，伸長(zhǎng)率和斷裂韌性明顯升高。在偏移量10mm且異速比為1.1的條件下，蛇形軋制試樣裂紋單位形核能提升高14%~36%。這是由于蛇形軋制能夠增強(qiáng)Al-Cu-Mg合金板材Cube織構(gòu)并減弱Brass織構(gòu)，形成具有更高裂紋擴(kuò)展阻力的織構(gòu)組態(tài)所致。
關(guān)鍵字: Al-Cu-Mg合金；蛇形軋制；力學(xué)性能；織構(gòu)；裂紋擴(kuò)展
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China; 2. Yunnan Metallurgical Group Co., Ltd, Kunming 650502, China; 3. Light Alloy Research Institute, Central South University, Changsha 410083, China; 4. State Key Laboratory of High Performance and Complex Manufacturing, Central South University, Changsha 410083, China）
Abstract:Based on the lab-made snake rolling mill, the effect of asymmetric boundary conditions on the mechanical properties and the microstructure of Al-Cu-Mg alloy rolled plates were investigated by room-temperature tensile, Kahn tear and electron back scattering diffraction (EBSD) tests. The results indicate that choosing a proper boundary condition can significantly improve the fracture toughness while maintaining the strength property. With increasing the differential peripheral speed ratio, the strength of the snake rolled plates rises, but the elongation and the fracture toughness decreases at the same offset distance. And with increasing the offset distance, the strength decreases with the dramatically elongation and fracture toughness increases at the same speed ratio. Under the condition of the offset distance of 10 mm and the speed ratio of 1.1, the crack unit initiation energy (UIE) of the snake rolled plates increase by 14%~36%. It is due to the enhanced Cube texture and the weakened Brass texture of the Al-Cu-Mg alloy plates rolled by snake rolling compared with the conventional rolling, which means the better texture components with higher crack propagation resistance.
Key words: Al-Cu-Mg alloy; snake rolling; mechanical property; texture; crack propagation
