超声铸造对AZ31镁合金铸锭及热轧板材组织与性能的影响  

Effects of ultrasonic vibration on microstructure and properties of as-cast and hot rolled AZ31 magnesium alloy

作　　者：余琨[1] 薛新颖[1] 毛大恒[2] 李建平[2] 胡亚男[1] 李少君[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]中南大学机电工程学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2011年第7期1918-1922,共5页Journal of Central South University:Science and Technology

基　　金：国家重点基础研究发展计划("973"计划)(2007CB613706)

摘　　要：采用超声铸造方法制备AZ31镁合金铸锭,并对其组织性能进行研究。研究结果表明：超声铸造后AZ31合金铸锭晶粒尺寸平均值为140μm,比常规铸造的铸锭晶粒尺寸350μm更细小,同时合金中第二相分布更加均匀弥散,这使合金铸锭的综合力学性能提高并有利于后续铸锭的热轧开坯。经过超声铸造的AZ31镁合金热轧后板材的晶粒尺寸（5~30μm）也比常规铸造锭坯热轧板材晶粒尺寸（40~60μm）要细小,这使超声铸造AZ31镁合金热轧后板材的典型力学性能比常规铸造后热轧的合金板材的好,抗拉强度提高约18%,伸长率相当;超声铸造有利于细化AZ31镁合金晶粒,改善第二相在枝晶间的分布,提高合金的力学性能和加工变形能力。The ultrasonic vibration was introduced into the solidification of the AZ31 magnesium alloy.The results show that the average grain size of the experimental alloy ingots is about 140 μm,which is smaller of AZ31 alloy with ordinary casting process.Meanwhile,the intermetallics of experimental alloy distribute more uniform and disperse.Such structure is attribute to enhancing ingot＇s mechanical properties and benefit to the sequential hot rolling.The grain size（5？30 μm） of hot rolled plate is produced by casting with ultrasonic vibration and sequential hot rolling is smaller than that（40？60 μm） of plate prepared by ordinary casting process.The mechanical properties of AZ31 magnesium alloy plate produced by ultrasonic vibration casting and sequential hot rolling are greatly improved due to the microstructure modification.The tensile strength increases by 18%,and the elongation is maintained.Ultrasonic vibration casting process enhances the mechanical properties and refines microstructure of AZ31 magnesium alloy and improves its deformability.

关 键 词：超声铸造 AZ31镁合金 显微组织 力学性能 

分 类 号：TG146[一般工业技术—材料科学与工程]