Mg-Sr-Al-Y合金的微观组织结构与高温压缩变形行为

为改善镁合金耐热性能,以Mg-Sr-Y三元合金为基础,采用"熔-浸"还原法,制备Mg-Sr-Al-Y合金。借助XRD、OM、SEM、TEM和带有加热装置的万能拉伸试验机等手段,研究分析了Mg-Sr-Al-Y合金的显微组织、力学性能和高温压缩变形机制。结果表明:Mg-Sr-Al-Y合金由α-Mg、Mg17Sr2和Al2Y相组成;Mg-Sr-Al-Y合金的流变应力随压缩温度升高而降低,随应变速率增大而提高;应变速率较低时,Mg-Sr-Al-Y合金再结晶较为明显。该研究通过添加金属Al,明显改善了Mg-Sr-Y合金的显微组织,提高了Mg-Sr-Al-Y合金的高温压缩性能。

Microstructures and high-temperature compressive deformation of Mg-Sr-Al-Y alloys

Aimed at improving the heat resistance performance of magnesium alloys,this paper introduces the successful fabrication of Mg-Sr-Al-Y alloys,based on the Mg-Sr-Y alloy and using melting-leaching reduction method,and the analysis of the microstructures and mechanical properties and compressive behaviors by means of OM and SEM and XRD and tensile machine attached to a heating furnace.The results show that Mg-Sr-Al-Y alloy composed of α-Mg and Mg17Sr2 and Al2Y,has a decreasing flow stress with increasing temperature and a increasing flow stresses with increasing strain rate.A lower strain rate triggers the obvious recrystallization of Mg-Sr-Al-Y alloys.The results also prove that the addition of Al and Y elements could produce a significant improvement in microstructures and heat resistance performance of Mg-Sr-Al-Y alloys.