Effect of Ce on microstructure and thermal conductivity of as-cast Mg-6Zn alloy
DAI Xiao-teng1, MA Ming-long1, ZHANG Kui1, LI Yong-jun1, YUAN Jia-wei1, LIU Xiao-dao2, WANG Sheng-qing2
1. State Key Laboratory of Nonferrous Metals and Processes, GRIMAT Engineering Institute Co., Ltd., Beijing 101499, China;
2. Nanjing Yunhai Special Metals Co., Ltd., Nanjing 211224, China
Abstract:The microstructure of as-cast Mg-6Zn-xCe alloy was investigated by optical microscope (OM), X-ray diffraction (XRD), scanning election microscopy (SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM)and the changing rule of thermal conductivity with the content of Ce was investigated using the flash method. The results show that Mg-6Zn alloy is mainly composed of α-Mg and Mg7Zn3 phases. The ternary phase Ce5 (Mg,Zn)41 which is mainly distributed between grain boundaries and dendrites appears in the alloy after the addition of the rare earth element Ce, and the appearance of ternary phase has an inhibitory effect on Mg7Zn3 phase. The content of eutectic structure is increased by the addition of Ce, and the distribution continuity is improved with the increase of Ce content. The thermal conductivity of the alloy is decreased with the increase of Ce content, which may be caused by the increase of volume fraction, more continuous distribution of eutectic structure in the alloy, the enhanced electron scattering, the extended electron conduction paths and the increased thermal resistance, ultimately the thermal conductivity of the alloy is reduced.
代晓腾, 马鸣龙, 张奎, 李永军, 袁家伟, 刘小稻, 王胜青. Ce对铸态Mg-6Zn合金组织与导热性能的影响[J]. 材料工程, 2020, 48(1): 92-97.
DAI Xiao-teng, MA Ming-long, ZHANG Kui, LI Yong-jun, YUAN Jia-wei, LIU Xiao-dao, WANG Sheng-qing. Effect of Ce on microstructure and thermal conductivity of as-cast Mg-6Zn alloy. Journal of Materials Engineering, 2020, 48(1): 92-97.
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