Mn对Mg-Zn-Ca-Mn合金显微组织和力学性能的影响  

Effect of Mn on Microstructure and Mechanical Properties of Mg-Zn-Ca-Mn Alloys

作　　者：庄园[1] 于彦东[1] 裴腾[1] 

机构地区：[1]哈尔滨理工大学材料科学与工程学院,黑龙江哈尔滨150040

出　　处：《哈尔滨理工大学学报》2013年第1期55-60,共6页Journal of Harbin University of Science and Technology

基　　金：黑龙江省自然科学基金重点项目(ZD201202)

摘　　要：为了研究不同Mn含量对Mg-2Zn-0.5Ca-xMn新型医用镁合金显微组织和力学性能的影响,利用光学显微镜、X射线衍射仪、扫描电镜和电子万能试验机分析Mg-2Zn-0.5Ca-xMn镁合金析出相、热挤压显微组织及力学性能.结果表明:铸态Mg-2Zn-0.5Ca-xMn合金组织主要由α-Mg基体组成,热处理前后第二相成分均为Mg0.97Zn0.03、MgZn2、Mg2Ca及Mn颗粒;Mn以单质形式弥散分布于基体内,细化铸态Mg-2Zn-0.5Ca-xMn合金晶粒,并且阻碍热挤压过程中动态再结晶晶粒长大,使晶粒尺寸随着Mn含量的增加而减小;随着Mn含量的增加,挤压态Mg-2Zn-0.5Ca-xMn合金强度逐渐增加,塑性有所降低.Mn质量分数为1.5%的合金抗拉强度最大,达245MPa;Mn质量分数为0.5%的合金断面收缩率和断后伸长率较大,分别为31%和12.5%.In order to investigate the effect of Mn concentration on microstructure and mechanical properties of Mg-2Zn-0. 5Ca-xMn alloys for new biomedical application, the precipitated phases, microstructure and mechanical properties of extruded Mg-2Zn-0. 5Ca-xMn alloys were analyzed by means of optical microscope, X-ray diffraction, scanning electron microscopy and electronic universal testing machine. The results indicate that the microstructure of as-cast Mg-2Zn-0. 5Ca-xMn alloys is mainly composed of a-Mg matrix and the second phase components are Mg0.97Zno.03, MgZn2, Mg2Ca and Mn particles; Mn disperses in the matrix in the form of a simple substance, re- fines the grains of as-cast Mg-2Zn-0. 5Ca-xMn alloys and hinders dynamic reerystallization grain growth in the process of hot extrusion, which makes the grain size decrease with Mn addition; As the Mn content increases, the strength of extruded Mg-2Zn-0. 5Ca-xMn alloys gradually ascends, but the plastic shows a declining trend, wherein the tensile strength of alloys with Mn content of 1.5% （mass fraction） is maximum, up to 245MPa, and section shrinkage and elongation rate of 0. 5% Mn content alloys reach the highest point at 31% and 12.5% respectively.

关 键 词：可降解镁合金 显微组织 热挤压 动态再结晶 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]