标题：Revealing the roles of Al4C3and Al8Mn5during α-Mg nucleation in Mg-Al based alloys
作者：Han M.; Zhu X.; Gao T.; Liu X.
作者机构：[Han, M] Key Laboratory of Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, 17923 Jingshi Ro 更多
通讯作者地址：[Liu, X] Key Laboratory of Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, 17923 Jingshi Ro 更多
来源：Journal of Alloys and Compounds
关键词：Al4C3; Grain refinement; Metals and alloys; Microstructure; Mn
摘要：Debate on the accurate heterogeneous nucleus of α-Mg in carbon-inoculated Mg-Al based alloys has lasted for decades, due to the difficulty of phase identification since aluminum carbide readily hydrolyzes. In this paper, a novel Al-3C master alloy was used as the refiner and to reveal the α-Mg nucleating substrate. To avoid hydrolysis, focused Ion Beam (FIB) was used to prepare samples, and Electron Back-Scattered Diffraction (EBSD) phase structure analysis was carried out to identify the phase type of the α-Mg nucleus. The experimental results indicate that a cluster of Al4C3particles rather than an individual particle acts as the α-Mg nucleus. The attachment of Al8Mn5particles to Al4C3particles restricts the nucleation efficiency. Nevertheless, Al4C3particles which have not been surrounded by Al8Mn5can still effectively refine α-Mg. Therefore, it is proposed that the addition of Al-3C master alloy can overcome the negative effect of Mn. Moreover, the excellent stability of Al4C3in Mg-Al based melts contributes to its remarkable refining and fade-resistant abilities. ï¿½ 2017 Elsevier B.V.