摘要
采用热模拟试验对一种含银Al-Cu-Mg耐热铝合金进行热压缩试验,研究了合金在热压缩变形温度和应变速率分别为340-500℃,0.001-10s^-1的条件下的流变应力行为和变形组织。结果表明：合金的流变应力随应变速率的增大而增大,随变形温度的升高而减小。该合金热压缩变形的流变应力行为可用双曲正弦形式的本构方程来描述,也可用Zener-Hollomon参数来描述,其变形激活能为196.27kJ/mol。在较低的变形温度或较高的应变速率下,合金组织中主要存在沿垂直于压缩方向拉长了的晶粒。随着变形温度的升高或应变速率的降低,拉长的晶粒发生粗化,并且合金中出现了再结晶晶粒,说明合金中的主要软化机制逐步由动态回复转变为动态再结晶。该合金较适宜的热轧温度为380-460℃,应变速率为0.1-10s^-1。
The behavior of the flow stress of Ag-contained Al-Cu-Mg beat-resistant aluminum alloy during hot compression deformation was studied by thermal simulation test. The temperature and the strain rate during hot compression were 340 - 500℃ , 0. 001 - 10s^ -1 , respectively. The results show that the flow stress increases with increasing the strain rate, and decreases with increasing the deforming temperature. The flow stress of the alloy during hot compression deformation can be described by constitutive equation in hyperbolic sine function with the hot deformation activation energy 196.27 kJ/mol, and can also be described by a Zener-Hollomon parameter. Only elongated grains vertical to compression direction were observed in the alloys deformed at low temperature or high strain rate. With increasing deformation temperature or decreasing strain rate, the elongated grains eoarsed and reerystallization grains were also observed, indicating that the main soften mechanism of the alloy transformed from dynamic recovery to dynamic recrystallization. The suitable hot rolling temperature is 380 -460℃ and the strain rate is 0. 1 - 10s^-1.
出处
《航空材料学报》
EI
CAS
CSCD
北大核心
2009年第3期27-32,共6页
Journal of Aeronautical Materials
基金
国防科工委军品配套研制项目(JPPT-115-2-948)
关键词
耐热铝合金
含银Al-Cu-Mg合金
流变应力
变形组织
heat-resistant aluminum alloy
Ag-contained Al-Cu-Mg alloy
flow stress
deformed mierostrueture
