(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083；2. 東北輕合金有限責(zé)任公司，哈爾濱 150060)
摘 要: 采用高溫瞬時拉伸試驗(yàn)和電子顯微鏡研究Al-Mg-Sc合金在高溫下的塑性變形特征。結(jié)果表明，隨試驗(yàn)溫度升高，合金高溫瞬時拉伸強(qiáng)度下降，而塑性增加，350~400 ℃實(shí)驗(yàn)溫度下合金的變形抗力相對較低，熱塑性較好。大生產(chǎn)條件下的熱加工工藝驗(yàn)證試驗(yàn)也表明，350~470 ℃實(shí)驗(yàn)溫度范圍內(nèi)鑄錠熱加工溫度越高，軋制開裂的幾率越大，Al-Mg-Sc合金適宜的熱軋溫度為350~420 ℃。另外，大生產(chǎn)條件下還應(yīng)嚴(yán)格控制熱加工道次和道次變形量，開始軋制時道次壓下量和軋制速度不宜過大，軋制變形量超過25%后，應(yīng)逐漸加大道次壓下量和提高軋制速度，使變形深透到整個軋件厚度。
關(guān)鍵字: Al-Mg-Sc合金；熱塑性；熱軋工藝；顯微組織
（1. School of Materials Science and Technology, Central South University, Changsha 410083,China;2. Northeast Light Alloy Co. Ltd., Harbin 150060, China）
Abstract:Abstract: The flow behavior of Al-Mg-Sc alloy during high temperature plastic deformation was studied by high temperature tensile test and electronic microstructure analysis. The results show that the strength decreases and the plasticity increases with the increase of tensile testing temperature. The strength is lower and the hot plasticity is better when the test temperature is 350−400 ℃. The heat rolling processing at industrial production condition also shows that the rolling crack is easily formed when the heat processing temperature is higher. The best rolling temperature of Al-Mg-Sc alloy is 350−420 ℃. In addition, at the industrial production condition the heat processing pass and pass deformation ratio should be controlled. The pass deformation amount and rolling velocity should not be large at beginning. When deformation ratio is beyond 25%, the pass deformation ratio and rolling velocity should be gradually enhanced.
Key words: Al-Mg-Sc aluminum alloy; thermo-plasticity; hot rolling; microstructure
