The structure of the aluminium-abundant γ-brass-type Al8.6Mn4.4

Qifa Hu; Bin Wen; Changzeng Fan

doi:10.1107/S2414314621009883

The structure of the aluminium-abundant γ-brass-type Al_8.6Mn_4.4

IUCrdata. 2021 Sep 24;6(Pt 9):x210988. doi: 10.1107/S2414314621009883. eCollection 2021 Sep.

Authors

Qifa Hu¹, Bin Wen¹, Changzeng Fan¹

Affiliation

¹ State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, People's Republic of China.

Abstract

An aluminium-abundant Al₈Mn₅/γ-brass-type inter-metallic with formula Al_8.6Mn_4.4, which is isotypic with γ-Al₈Cr₅ and γ-Al₈V₅, was discovered by high-temperature sinter-ing of an Al/Mn mixture with initial composition Al₂Mn. Structure analysis revealed that one special position (Wyckoff site 18h in space group R m) is shared by Al and Mn, with refined site occupancy factors of 0.7 and 0.3, respectively. The present low-temperature Al₈Mn₅-type phase crystallizes in the centrosymmetric space group R m (No. 166), rather than R3m (No. 160) as previously reported for the same inter-metallic characterized by TEM measurements [Zeng et al. (2018 ▸). Acta Mater. 153, 364-376].

Keywords: Al–Mn; crystal structure; intermetallic; γ-brass phase.

Grants and funding

Funding for this research was provided by: Research Foundation of Education Bureau of Hebei Province (grant No. ZD2018069); The National Natural Science Foundation of China (grant No. 51771165).