2A12硬铝合金热拉伸流变行为及本构建模  

Hot tensile flow behavior and constitutive model of aluminum alloy 2A12

作　　者：李先梦 湛利华[1] 申儒林[1] 郭亮[1] Li Xianmeng Zhan Lihua Shen Rulin Guo Liang(College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China)

机构地区：[1]中南大学机电工程学院,湖南长沙410083

出　　处：《锻压技术》2017年第4期159-164,193,共7页Forging & Stamping Technology

基　　金：国家自然科学基金资助项目(51235010);湖南省自然科学基金资助项目(13JJ2009);中南大学"创新驱动计划"项目(2015CX002);高等学校博士学科点专项科研基金(20120162110003)

摘　　要：在变形温度350~500℃、应变速率0.01~1 s^(-1)条件下,利用Gleeble-3500热模拟实验机对2A12硬铝合金板进行热拉伸实验。结果表明:峰值应力随温度升高而减小,随应变速率提高而增大;随着应变速率减小,断裂总伸长率升高,而均匀伸长率降低;应变速率较低时,其断裂总伸长率在350~450℃时较高,升高到500℃时迅速降低,均匀伸长率则对温度变化不敏感;应变速率较高时,试样断裂总伸长率对温度变化不敏感,均匀伸长率随温度升高而降低。根据实验结果,采用Z参数建立的流变应力本构模型,能较好地描述2A12铝合金板材热拉伸变形下的流变行为。Under the condition of deformation temperature of 350 -500℃ and strain rate of 0. 01 - 1 s -1, the hot tensile test of 2A12 aluminum alloy sheet was carried out by Gleeble -3500 thermal simulation machine. The results show that the peak stress decreases with the increase of deformation temperature and increases with the increase of strain rate. However, with the decrease of strain rate, the total elongation of fracture increases, but the uniform elongation decreases. Furthermore, when the strain rate is low, the total elongation of fracture is higher at 350 - 500 ~C, then declines rapidly at 500℃ but the uniform elongation of fracture is not sensitive to temperature change. When the strain rate is high, the total elongation of fracture is not sensitive to temperature change, and the uniform elongation decreases with the increase of temperature. According to the experimental results, a flow stress constitutive model using Z parameter is established, and the flow behavior of 2A12 aluminum alloy sheet under hot tensile deformation can be better represented.

关 键 词：2A12硬铝合金 峰值应力 断裂总伸长率 均匀伸长率 本构模型 

分 类 号：TG146.21[一般工业技术—材料科学与工程]