摘要
利用分离式Hopkinson拉杆设备对五种航空常用铝合金2A12-CZ,2A12-M,2024-T351,7050-T74,7050-T7451进行了室温动态拉伸力学性能探究,并利用电子万能试验机对这五种材料进行了准静态拉伸力学性能测试,得到了五种铝合金在不同应变率下的拉伸真实应力应变曲线。试验结果显示:7050系列铝合金有较高的屈服强度,2A12M抗拉强度则最低。五种航空铝合金都表现出不同程度的正的应变率敏感效应,其中2A12-CZ敏感性最强,7050T7451敏感性最弱。五种铝合金动态拉伸失效应变明显大于准静态拉伸失效应变。2A12M与2024T351有较高的动态拉伸失效应变。在试验结果的基础上,选择Johnson-Cook本构模型,Cowper-Symonds本构模型来拟合这五种材料的动态本构,模型预测与试验结果吻合较好。
The dynamic as well as quasi-static tensile response of five kinds of commonly used aluminium alloys （i. e. 2A12-CZ,2A12-M,2024-T351,7050-T74 and 7050-T7451 ） were investigated by using split Hopkinson tension test （SHTB） and universal test machine. The results show that the yield stress of 7050 aluminium alloys is higher than the others. 2A12-M alloy has the lowest tensile strength among the five kinds of alloys. All of the five kinds of alloys have positive strain-rate sensitivity. The strain-rate sensitivity of 2A12-CZ is high, while the strain-rate sensitivity of 7050-T7451 is low. The dynamic tensile failure strain is much higher than the quasi-static tensile failure strain for all tested alloys. 2A12-M alloy and 2024-T351 alloy have higher dynamic tensile failure strain than the others. Finally, the Johnson-Cook and Cowper-Symonds models were chosen to characterize aluminium alloys＇ behavior and the parameters were obtained by fitting the experiment data. The models coincide with the experiment results fairly well.
出处
《航空材料学报》
EI
CAS
CSCD
北大核心
2013年第4期71-77,共7页
Journal of Aeronautical Materials
基金
自然科学基金(11102166
10932008)
111计划(B07050)
关键词
铝合金
动态拉伸
应变率敏感性
屈服强度
本构模拟
aluminium alloys
dynamic tension
strain rate sensitivity
yield stress
simulation model
