铸造Mg-RE合金晶粒细化行为研究现状与展望  

Grain Refinement of As-Cast Mg-RE Alloys: Research Progress and Future Prospect

作　　者：吴国华[1,2] 童鑫 蒋锐 丁文江[1,2] WU Guohua;TONG Xin;JIANG Rui;DING Wenjiang(National Engineering Research Center of Light Alloys Net Forming,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;State Key Laboratory of Metal Matrix Composite,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学材料科学与工程学院轻合金精密成型国家工程研究中心,上海200240 [2]上海交通大学材料科学与工程学院金属基复合材料国家重点实验室,上海200240

出　　处：《金属学报》2022年第4期385-399,共15页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目Nos.U2037601、51821001和51775334;上海航天先进技术联合研究基金项目No.USCAST-2020-31。

摘　　要：轻质高强耐热的镁稀土(Mg-RE)合金大型复杂铸件在航空航天、国防军工装备轻量化等方面展现出独特的优势。对铸造Mg-RE合金进行晶粒细化处理能够显著改善合金的强度、塑韧性以及铸造工艺性能,对拓宽其应用领域意义重大。本文首先基于成分过冷和异质形核,探讨了稀土元素及外加颗粒对镁合金晶粒细化的影响。归纳了适用于铸造Mg-RE合金的化学、物理细化方法及其作用机制,并系统论述了晶粒细化对铸造Mg-RE合金铸造工艺性能、力学性能及腐蚀性能的影响。最后面向Mg-RE合金的实际应用需求,对其细化处理方面存在的不足和发展趋势进行了探讨。Magnesium rare-earth(Mg-RE) alloy castings with a large size and complex structure exhibit versatile prospects in critical aircraft, aerospace, and defense fields owing to their ultralow density,excellent specific strength, and high-temperature resistance. The grain refinement of cast Mg-RE alloys can significantly improve their strength, plasticity, toughness, and casting performance, which are critical for expanding their applications. In this work, the grain refinement mechanism of Mg alloys by introducing RE elements and heterogeneous particles is first discussed based on the classical theory of constitutional supercooling and heterogeneous nucleation. Various grain refinement technologies for Mg-RE alloy casting using chemical and physical methods are comprehensively summarized. Further, the influence of grain refinement on the casting performance, mechanical properties, and corrosion properties of Mg-RE cast alloys is thoroughly discussed. Finally, the deficiencies and development trends of the current grain refinement of Mg-RE alloys are discussed from the point of actual application requirements.

关 键 词：Mg-RE合金 晶粒细化 理论模型 凝固组织 性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]