A study of the Al–Mn–Pt alloy system

• Published in: Journal of alloys and compounds 2019-07, Vol.792, p.1223-1229
• Main Author: Grushko, B.
• Format: Article
• Language: English
• Subjects: Alloy systems; High temperature; Manganese; Phase diagrams; Phase equilibria; Phases; Platinum base alloys; Scanning electron microscopy; Ternary systems; Transition metal alloys and compounds; X ray powder diffraction; X-ray diffraction
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.04.130

Phase equilibria in Al–Mn–Pt were studied at 800–1100 °C below 60 at.% Pt by scanning electron microscopy and powder X-ray diffraction. The high-temperature phases AlPt and MnPt probably form a continuous region β with the CsCl-type structure. The Al2Pt and Al3Pt2 phases were found to propagate up to at least Al20.0Mn52.4Pt27.6 and Al55Mn5Pt40, respectively. Wide ternary regions were found to extend from Mnβ, Mnγ and Mnδ. The AlMnPt phase (P63/mmc, a = 0.4329, c = 0.5499 nm) reported earlier was found to be formed in a compositional region between Al32.3Mn31.5Pt36.2 and Al19.7Mn44.3Pt36.0. The study revealed the formation of two other ternary phases designated χ and X. The χ-phase of the Al28Ir9 type structure (P31c, a = 1.2207, c = 2.7248 nm) was revealed at ∼ Al75.3-76.0Mn3.4-4.8Pt21.3-19.2. The structure of the X-phase existing between Al79.9Mn15Pt5.1 and Al71.8Mn25.5Pt2.7 was not specified. [Display omitted] •Al2Pt propagates up to Al20.0Mn52.4Pt27.6, Al3Pt2 up to Al55Mn5Pt40.•AlMnPt phase was found at Al32.3-19.7Mn31.5-44.3Pt36.2-36.0.•Ternary χ-phase was revealed at Al75.3-76.0Mn3.4-4.8Pt21.3-19.2.•Ternary X-phase was revealed at Al79.9-71.8Mn15.0-25.5Pt5.1-2.7.