Effects of La and Ce on the microstructure,thermal conductivity and strength synergy of the as-extruded Mg-Mn-RE alloys  

作　　者：Huafeng Liu Taiki Nakata Chao Xu Guangze Tang Danyang Li Xiaojun Wang Guisong Wang Shigeharu Kamado Lin Geng 

机构地区：[1]State Key Laboratory of Precision Welding&Joining of Materials and Structures,Harbin Institute of Technology,Harbin,150001,PR China [2]School of Materials Science and Engineering,Harbin Institute of Technology,Harbin,150001,PR China [3]Department of Mechanical Engineering,Nagaoka University of Technology,Nagaoka,940-2188,Japan [4]Laboratory for Space Environment and Physical Sciences,Harbin Institute of Technology,Harbin,150001,PR China [5]School of Physics,Harbin Institute of Technology,Harbin,150001,PR China

出　　处：《Journal of Magnesium and Alloys》2025年第2期654-667,共14页镁合金学报(英文)

基　　金：supported by National Key Research&Development Program of China(Grant Nos.2021YFB3703300,2021YFE010016 and 2020YFA0405900);National Natural Science Foundation(Grant Nos.52220105003 and 51971075);the Fundamental Research Funds for the Central Universities(Grant No.FRFCU5710000918);Natural Science Foundation of Heilongjiang Province-Outstanding Youth Fund(Grant No.YQ2020E006);JSPS KAKENHI(Grant No.JP21H01669).

摘　　要：High thermal conductivity and high strength Mg-1.5Mn-2.5Ce alloy with a tensile yield strength of 387.0 MPa,ultimate tensile strength of 395.8 MPa,and thermal conductivity of 142.1 W/(m·K)was successfully fabricated via hot extrusion.The effects of La and Ce additions on the microstructure,thermal conductivity,and mechanical properties of the Mg-1.5Mn alloy were investigated.The results indicated that both the as-extruded Mg-1.5Mn-2.5La and Mg-1.5Mn-2.5Ce alloys exhibited a bimodal grain structure,with dynamically precipitated nano-scaleα-Mn phases.In comparison with La,the addition of Ce enhanced the dynamic precipitation more effectively during hot extrusion,while its influence on promoting the dynamic recrystallization was relatively weaker.The high tensile strength obtained in the as-extruded Mg-1.5Mn-2.5RE alloys can be attributed to the combined influence of the bimodal grain structure(with fine dynamic recrystallized(DRXed)grain size and high proportion of un-dynamic recrystallized(unDRXed)grains),dense nano-scale precipitates,and broken Mg12RE phases,while the remarkable thermal conductivity was due to the precipitation of Mn-rich phases from the Mg matrix.

关 键 词：Mg-Mn-RE alloys Thermal conductivity Mechanical properties Dynamic precipitation 

分 类 号：TG146.2[一般工业技术—材料科学与工程]