( 1. 重慶大學(xué) 材料科學(xué)與工程學(xué)院, 重慶 400044；
2. 西南鋁業(yè)(集團(tuán))有限責(zé)任公司, 重慶 401326)
摘 要: 在Gleeble-1500D熱模擬儀上進(jìn)行熱壓縮實(shí)驗(yàn)， 研究了變形溫度為573~773 K、 應(yīng)變速率為0.01~10 s-1時(shí)2618鋁合金的熱變形行為。 熱變形過程中的穩(wěn)態(tài)流變應(yīng)力可用雙曲正弦本構(gòu)關(guān)系式來描述， 平均激活能為181 kJ/mol， 大于其自擴(kuò)散激活能。 根據(jù)材料動(dòng)態(tài)模型， 計(jì)算并分析了2618鋁合金的加工圖。 利用加工圖確定了熱變形的流變失穩(wěn)區(qū)， 并且獲得了試驗(yàn)參數(shù)范圍內(nèi)的熱變形過程的最佳工藝參數(shù)， 其熱加工溫度為623~723 K， 應(yīng)變速率為0.01 s-1， 溫加工溫度為573 K左右， 應(yīng)變速率為0.01 s-1。
關(guān)鍵字: 2618鋁合金; 流變應(yīng)力; 加工圖; 熱變形
2618 aluminum alloy
HUANG Guang-jie1, ZHANG Suo-quan1
（ 1. College of Materials Science and Engineering,
Chongqing University, Chongqing 400044, China;
2. Southwest Aluminium Group Co., Ltd.,
Chongqing 401326, China）
Abstract: The deformation behaviour of 2618 aluminum alloy was investigated by compression tests with Gleeble-1500D thermal simulator system. The tests were performed in the temperature range between 573 and 773 K and strain rates between 0.01 and 10 s-1. The flow behaviour is described by the hyperbolic sine constitutive equation， and an activation energy of 181 kJ/mol greater than the activation energy for self-diffusion in Al is calculated. The processing maps were calculated and analyzed according to the dynamic materials model. The process of hot deformation in the temperature range and different strain rate can be attained by the maps, which hot deformation temperature is 623-723 K and strain rate is around 0.01 s-1. The warm deformation temperature is approximately 573 K and strain rate is also about 0.01 s-1. The instability zones of flow behaviour can also be recognized by the maps.
Key words: 2618 aluminum alloy; flow stress; processing maps; hot deformation
