高强超声对Mg—Zn—Er合金显微组织和性能的影响.pdfVIP

学兔兔 NOV．2009 铸 造 VOI．58 N0．11 FOUNDRY ·11O1· 高强超声对Mg—Zn—Er合金显微组织和性能的影响 周天承 ，杜文博 ，王朝辉 ，李淑波 ，赵宇昕： (1．芜湖职业技术学院，安徽芜湖241006；2．北京工业大学材料科学与工程学院，北京100022) 摘要：采用高强超声熔体处理法制备Mg．Zn．Er合金，研究了超声处理时间和超声输出功率对镁合金铸态显微组织和性 能的影响。研究结果表明，随超声处理时间的延长或超声输出功率的增大，合金的铸态显微组织由粗大的枝晶转变为 细小均匀圆整的晶粒，当处理时间或输出功率达到一定值后再延长处理时间或增大输出功率，组织有粗化的趋势。合 金凝固组织中产生了沿晶界不连续分布的析出相和大量均匀弥散分布于合金基体中的析出相微粒。当熔体温度、超声 处理时间和超声输出功率分别为718℃、100 s和600W时，制得的Mg一5Zn一2Er合金晶粒细小均匀圆整，其室温抗拉强度 和伸长率分别为199．6MPa和l1．6％。 关键词：高强超声；镁合金；显微组织；性能；超声空化 中图分类号：TG146．T2 文献标识码：A 文章编号：lO01—4977(2009)11—1 101—04 Effect of High—Intensity Ultrasonic on Microstructure and Properties of Mg--Zn--Er Alloy ZHOU Tian-cheng’，DU Wen—bo ，WANG Zhao-hui ，LI Shu-bo ，ZHAO Yu-xin (1．Wuhu Institute of Technology，Wuhu 241 006，Anhui，China；2．College of Material Science and Engineering，Beijing University of Technology，Beijing 1 00022，China) Abstract：Mg—Zn—Er alloy was prepared by high—intensity ultrasonic melt treatment．The effects of the ultrasonic treatment time and ultrasonic output power on microstructure and properties of Ma．Zn．Er alloy were investigated．The results show that with increase in the ultrasonic treatment time or ultrasonic output power．the microstructure of the as-cast Mg-Zn—Er alloy transforms fr0m bulky dentrite into smalI uniformitv rotundity grain．Further prolonging time or output power rising will cause the microstructure to become coarse when the ultrasonic treatment time or ultrasonic output power reaches a fixed value．It was found that the separated discOn nu0us phases existed along grain boundaries and a mass of particulates uniformlV dispersed in the matrix of the alloy．When the melt temperature，ultrasonic trea