铝合金挤压型材的拉伸失效行为研究

Research on tensile failure behavior of aluminum alloy extruded profiles

为了研究挤压速度、预热温度、挤压角度等对铝合金性能的影响,通过熔炼、差压铸造、挤压制备出铝合金型材,用万能试验机完成双向拉伸试验,用扫描电子显微镜观察显微组织,分析差压铸造铝合金经挤压后的拉伸失效行为。结果表明:双向拉伸后,铝合金型材出现较严重的变形,挤压角度为90°时,铝合金挤压型材不易拉断;挤压速度为1.5 mm/s时拉伸损伤概率更低;预热温度为250℃时拉伸后韧窝更密集,不易脆性断裂。

In order to study the influence of extrusion speed,preheating temperature and extrusion angle on the properties of aluminum alloy,aluminum alloy profiles were prepared by melting,differential pressure casting and extrusion.The bidirectional tensile test was completed by universal testing machine,and the microstructure was observed by scanning electron microscope to analyze the tensile failure behavior of differential pressure casting aluminum alloy after extrusion.The results show that the aluminum alloy profiles have serious deformation after bidirectional stretching.When the extrusion angle is 90°,the aluminum alloy profiles are not easy to break.The probability of tensile damage is lower when the extrusion speed is 1.5 mm/s.When the preheating temperature is 250℃,the dimple is more dense after stretching,and it is not easy to brittle fracture.