5A30铝合金板高温拉伸本构关系研究

Constitutive Relationship of 5A30 Aluminum Alloy Sheet at Elevated Temperature

采用拉伸试样在Gleeble-1500材料热模拟试验机上对5A30铝合金进行高温拉伸实验,研究了该合金在变形温度为300～500℃,应变速率在0.01～10 s-1的高温流变变形行为。结果表明:变形温度和应变速率对该合金流变应力的大小有显著影响。流变应力随变形温度的升高而降低,随着应变速率的增加而升高。5A30铝合金的高温流变行为可用Zener-Hollomon参数描述,从流变应力、应变速率和变形温度的相关性,得出了该铝合金板材高温变形的材料常数和本构方程。计算出5A30铝合金板的变形激活能为Q=201.1 kJ.mol-1,材料常数为A=7.44×1013 s-1,n=4.3135,α=0.02 mm2.N-1;计算得到了5A30铝合金Arrhenius方程;利用双曲正弦模型,得到高温拉伸峰值应力和Z参数的解析式。

The elevated temperature flow stress features of 5A30 aluminum alloys sheet were studied by tensile deformation of speci-men at 300 ～ 500 ℃ and high temperature deformation at strain rate of 0.01 ～ 10 s-1 with Gleeble-1500 simulated machine.The re-sults showed that the flow stress was influenced dramatically by strain rate and deformation temperature.The flow stress increased with strain rate increase and decreased with deformation temperature increase.The flow stress of 5A30 aluminum alloy sheet during hig...