(1. 西南大学 材料与能源学院，重庆 400715；
2. 重庆大学 国家镁合金材料工程与技术研究中心，重庆 40044)
摘 要: 镁是密排六方结构金属，滑移系较少，其基面滑移阻力比柱面和锥面滑移阻力低很多，基面滑移启动后其他滑移系很难启动，导致镁合金室温和低温的塑性变形能力较差。重庆大学等单位研究发现某些特定原子固溶在镁中既能阻碍基面位错滑移提高强度，又能通过缩小基面与非基面滑移阻力差距促进非基面滑移开启而改善塑性，达到同时提高镁合金强度和塑性的目的。重庆大学镁合金科研团队把这一结果发展为“镁合金固溶强化增塑”合金设计理论(Solid solution strengthening and ductilizing, SSSD)。这一合金设计理论在过去十几年中已成为解决镁合金强度和塑性平衡优化的一条新途径。重庆大学应用该理论开发了多种新型高性能镁合金，其中10多个新合金已批准为国家标准牌号合金和国际标准牌号合金。
关键字: 镁合金；强度；塑性；固溶强化增塑
（1. School of Materials and Energy, Southwest University, Chongqing 400715, China;
2. National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, China）
Abstract:Mg has a HCP structure with few slip systems, and the slip resistance for basal slip is much lower than that of prismatic and pyramidal slip. It is generally difficult to activate non-basal slip at room and low temperature, resulting in a poor ductility and formability of magnesium alloys. Chongqing University and other institutions have found that the solution of certain elements in Mg can not only improve the strength by hindering the basal slip, but also improve the ductility by reducing the gap of slip resistance between basal slip and non-basal slip. According to these results, Chongqing University has proposed a theory of alloy design —— solid solution strengthening and ductilizing (SSSD) for magnesium alloy, which has become a new way to optimize the strength-ductility balance of magnesium alloys in the past decade. Using SSSD theory, Chongqing University has developed many new high performance magnesium alloys, among which over 10 alloys have been included in GB/T national standard and ISO international standard.
Key words: magnesium alloys; strength; ductility; solid solution strengthening and ductilizing
