(中南大学 材料科学与工程学院，湖南 长沙，410083)
摘 要: 制备3种挤压比分别为7.0，9.6，19.6的Mg-1.5Gd-0.2Ni(质量分数，%)合金，研究挤压比对合金微观组织、力学性能及腐蚀性能的影响。研究结果表明：随着挤压比从7.0增加至19.6，Mg基体再结晶越充分，其组织更加细小、均匀，因而提高了合金的综合力学性能。当挤压比为19.6时，合金的抗拉强度为228 MPa，屈服强度为167 MPa，断后伸长率为22.5%。挤压态合金在质量分数为3%KCl中的腐蚀速率比铸态合金的低。
关键词: 镁合金；挤压比；力学性能；腐蚀性能
（School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The Mg-1.5 Gd-0.2 Ni (mass fraction, %) alloys with three kinds of extrusion ratio (7.0, 9.6, 19.6) were prepared. The effects of extrusion ratio on microstructure, mechanical properties and corrosion properties of Mg-1.5 Gd-0.2 Ni alloy were investigated. The results show that as the extrusion ratio increases from 7.0 to 19.6, α-Mg grains are more sufficiently dynamic recrystallized, achieving the finer and more uniform microstructure as well as the improved comprehensive properties. The alloy with extrusion ratio of 19.6 exhibits the ultimate tensile strength of 228 MPa, tensile yield strength of 167 MPa, and elongation of 22.5%. The corrosion rate of the as-extruded alloys in 3% (mass fraction) KCl is much lower than that of the as-cast alloy.
Key words: magnesium alloys; extrusion ratio; mechanical properties; corrosion performance
