【摘要】 对工业纯铝L2进行了不同应变率下(O.001、0.02、200、500和1300 s-1)拉伸力学性能的试验,得到各应变率下完整的应力-应变曲线.试验结果表明:在应变率很低时,其屈服应力(σs)、拉伸强度(σb)和失稳应变(εb)随着应变率的增加变化不大;当应变率很高时,σe和σh随着应变率对数的增加而增大,而εb随着应变率的增加而减小;弹性模量则对应变率不敏感.采用修正的幂次强化模型及其简化模型来描述L2的应变率敏感行为,并采用Ramberg-Osgood模型拟合各个应变率下的应力应变曲线,结果表明,此两种模型能够很好地描述L2应变率相关的力学行为.更多还原

【Abstract】 Tensile experiments of aluminium L2 under different strain-rates (0. 001 s-1,0.02s-1、200 s-1, 500 s-1and 1 300 s-1) were carried out and the complete stress strain curves were obtained. The results show that the yield strength σs, the ultimate strength σb and the failure strain εb vary slightly under low strain-rates (ε< 0.02 s-1),σb and σs increase with the strain-rate but εb decreases with the strain - rate under high strain-rates(ε > 200 s-1) and the modulus E is insensitive to strain-rate. The strain-rate sensitivity is assumed to be consistent with the modified power-law of strain-rate hardening law and its simplified model, the Ramberg-Osgood model is adopted to simulate the stress-strain curves of L2 under different strain-rates. The simulated curves show good agreement with the experiment results.更多还原