7075铝合金高温热变形性能的研究  

Study on Thermal Deformation Performance of 7075 Alloy

作　　者：徐庆军[1] 张治民[2] 杨勇彪[1] 

机构地区：[1]中北大学材料科学与工程学院,山西太原030051 [2]山西省集成精密成形工程中心,山西太原030051

出　　处：《热加工工艺》2012年第7期33-35,共3页Hot Working Technology

摘　　要：采用Gleeble-3800热模拟机,沿与原材料轴线呈0°、45°、90°方向切割试样,在320、400和480℃,变形速率0.01、0.1和1/s时对7075铝合金进行试验。研究了温度、应变速率对7075铝合金热变形过程中力学性能及显微组织的影响。结果表明:在同一应变速率下,7075铝合金的流变应力和进入稳态流动时所需的应变随温度的升高而降低;在低温成形时,晶粒的形状连续而均匀;随着变形温度升高,晶粒逐渐变得粗大;在较高温度变形时,大晶粒周围有细小的等轴晶出现,发生了动态再结晶。在同一变形温度下,7075铝合金的流变应力随应变速率的增大而提高;应变速率越大,越易出现动态再结晶。Using Gleeble-3800 hot machine, along with raw materials axis 0°、45°、90° direction, samples was cut into style. At temperature 320 ℃, 400 ℃ and 480 ℃, with deformation rate 0.01 / s, 0.1 / s and 1 / s of 7075, the influence of temperature, strain rate on the thermal deformation of 7075 aluminum alloy in the process of mechanical properties and microstructure were tested. The results show that： at the same strain rate of 7075 aluminum alloy, the required deformation of flow stress and steady-state flow increase with temperature strain reduce; in the low temperature, the shape of the grain size of the forming is continuous and even; along with the deformation temperature increasing, grains gradually become bulky; at high temperature, large deformation grains around the tiny equiaxial crystal appear, and there is dynamic recrystallization. At the same temperature, the deformation of 7075 aluminum alloy rheological stress improves with the increase of strain rate; the greater the strain rate, the more probability that dynamic recrystallization forms.

关 键 词：7075铝合金 变形温度 变形速率 流变应力 

分 类 号：TG146[一般工业技术—材料科学与工程]