Liu Huafeng, Zuo Jing, Nakata Taiki, Xu Chao, Wang Guisong, Shi Hailong, Tang Guangze, Wang Xiaojun, Kamado Shigeharu, Geng Lin
School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Department of Mechanical Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka 940-2188, Japan.
Materials (Basel). 2022 Jan 29;15(3):1078. doi: 10.3390/ma15031078.
The effects of La addition on the microstructure, thermal conductivity and mechanical properties of as-cast and as-extruded Mg-3Al-xLa-0.3Mn (x = 1, 3 and 5 wt.%) alloys were studied. The results showed that the thermal conductivity of the alloys increased with the addition of La element, which was due to the formation of the AlLa phases by consuming the solute Al and the added La element. The yield strength of the as-cast Mg-3Al-xLa-0.3Mn alloys increased with the increase in La concentration. The thermal conductivity of the as-extruded alloys was lower than that of as-cast counterparts owing to lots of defects generated in the process of hot extrusion deformation, particularly the grain boundaries. The anisotropy of thermal conductivity was discovered in the as-extruded alloys on account of the formation of texture. As the La content increases, the tensile strength and yield strength of the as-extruded alloys decreased gradually. In contrast, the elongation first increased and then decreased, resulting from the combined effect of the texture strengthening and second phase strengthening.
研究了添加镧（La）对铸态和挤压态Mg-3Al-xLa-0.3Mn（x = 1、3和5 wt.%）合金的微观结构、热导率和力学性能的影响。结果表明，合金的热导率随着La元素的添加而增加，这是由于溶质Al和添加的La元素形成了AlLa相。铸态Mg-3Al-xLa-0.3Mn合金的屈服强度随着La浓度的增加而提高。挤压态合金的热导率低于铸态合金，这是由于在热挤压变形过程中产生了大量缺陷，特别是晶界。由于织构的形成，在挤压态合金中发现了热导率的各向异性。随着La含量的增加，挤压态合金的抗拉强度和屈服强度逐渐降低。相比之下，伸长率先增加后降低，这是织构强化和第二相强化共同作用的结果。
