摘要
为了开发高性能生物镁合金,采用模铸+半固态等温热处理+半固态挤压加工的工艺制备了4种ZM30-1Gd-1Nd镁合金,利用光学显微镜、扫描电镜、X射线衍射及电子探针等分析了合金微观组织,并使用万能拉伸机及电化学工作站测试了合金的力学性能及腐蚀速率。结果表明,4种合金组织主要由α-Mg、Mg7Zn3和W相(Mg3RE2Zn3)组成。等温热处理后ZM30-1Gd-1Nd层片状共晶结构逐渐溶解、棱角消失,转变成为细小颗粒。经过半固态热挤压加工后,组织发生了动态再结晶,层片状、网状分布的第二相破碎成为微米级细小颗粒。挤压比为64∶1的试样综合性能较优,平均抗拉强度和屈服强度分别达到272 MPa和191 MPa,在Hank's溶液中腐蚀速率最低,为1.21 mm/a,说明热挤压加工可改善ZM30-1Gd-1Nd镁合金的综合性能。
In order to obtain biological magnesium alloys with high performance,different kinds of ZM30-1Gd-1Nd magnesium alloys were prepared by mold casting+semi-solid isothermal treatment+semi-solid hot extrusion process.The microstructure of alloys was analyzed by optical microscope,scanning electron microscope,X-ray diffraction and electron probe,and mechanical properties and corrosion rate of alloys were tested by universal tensile testing machine and electrochemical workstation.The results reveal that the structures are composed of α-Mg,Mg_(7)Zn_(3) and W phase(Mg_(3)RE_(2)Zn_(3)).After isothermal heat treatment,the lamellar eutectic structure in ZM30-1Gd-1Nd is gradually dis⁃solved,and the edges and corners disappear,which is transformed into fine particles.After semi-solid hot extrusion,recrystallization occurs in the microstructure,and the second phase with lamellar and reticular distribution is broken into micron-sized fine particles.The specimen with extrusion ratio of 64∶1 exhibits desirable comprehensive properties.The average tensile strength and yield strength reach 272 MPa and 191 MPa,respectively,and the corrosion rate in Hank's solution is the lowest,which is 1.21 mm/a,indicating that hot extrusion can improve the comprehensive prop⁃erties of ZM30-1Gd-1Nd magnesium alloy.
作者
杨小涵
杨淼
郭恩宇
曹志强
YANG Xiaohan;YANG Miao;GUO Enyu;CAO Zhiqiang(School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024;Engineering Training Center,Beihua University,Jilin 132013;Ningbo Research Institute of Dalian University of Technology,Ningbo 315016)
出处
《特种铸造及有色合金》
北大核心
2025年第5期766-775,共10页
Special Casting & Nonferrous Alloys
基金
国家自然科学基金资助项目(52271024,52101036)
吉林省自然科学基金资助项目(YDZJ202101ZYTS172)。
关键词
稀土
医用镁合金
合金化
热挤压
组织性能演变
Rare Earth
Medical Mg Alloy
Alloying
Hot Extrusion
Evolution of Microstructure and Properties
