基于Malas准则的7050铝合金3D热加工图研究

Study on 3D Hot Processing Map of 7050 Aluminum Alloy Based on Malas Criterion

在Gleeble-3500热模拟试验机上进行了7050铝合金变形温度573~723 K、应变速率0.001~1 s^(-1)的等温热压缩试验,并对合金的热变形行为进行了研究。从流动应力曲线可以发现,流动应力随变形温度的增加而降低,且随应变速率的增加而增加,存在明显的高温软化和应变速率强化现象。在流动应力曲线基础上,基于Malas准则建立了7050铝合金的3D热加工图,确定出合适的热加工区域为变形温度700~723 K、应变速率0.001~0.006 s^(-1)。

Isothermal compression tests of 7050 aluminum alloy were carried out on Gleeble-3500 thermal simulator at the deformation temperature of 573-723 K and the strain rate of 0.001-1 s-1. And the hot deformation behavior of the alloy was studied. From the flow stress curve, it can be found that the flow stress decreases with the increase of deformation temperature, and increases with the increase of strain rate. There are the obvious phenomena of high temperature softening and strain rate strengthening. On the basis of the flow stress curves, the 3D hot processing map of 7050 aluminum alloy was established based on Malas criterion. The suitable hot processing zone is determined as the deformation temperature of 700- 723 K and the strain rate of 0.001-0.006 s-1.