Structural modifications in a Mn54Al43C3 melt-spun alloy induced by mechanical milling and subsequent annealing investigated by atom probe tomography

• Published in: Journal of alloys and compounds Vol. 581; pp. 86 - 90
• Main Authors: Le Breton, J.M., Bran, J., Folcke, E., Lucis, M., Lardé, R., Jean, M., Shield, J.E.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 25-12-2013; Elsevier
• Subjects: Annealing; Applied sciences; Atomic structure; Condensed matter: structure, mechanical and thermal properties; Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder; Cross-disciplinary physics: materials science; rheology; Crystalline state (including molecular motions in solids); Crystallographic aspects of phase transformations; pressure effects; Diffraction; Exact sciences and technology; Heat treatment; Materials science; Mechanical alloying and milling; Mechanical milling; Melt spinning; Metals. Metallurgy; Microalloying; Nanostructure; Nanostructured intermetallics; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Phase transformations; Physics; Powder metallurgy. Composite materials; Production techniques; Structure of solids and liquids; crystallography; Technology; Tomography; Nanostructured intermetallics; Microalloying; Mechanical alloying and milling; Beta phase; Annealing; Phase composition; Tetragonal lattices; Intermetallic compound; Melt spinning; Nanostructure; Alloying element; Mechanical alloying; X ray diffraction; Atom probe; Phase transformation; Tomography; Structure modification; Crystal-phase transformations
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2013.07.002

•A Mn54Al43C3 alloy was studied by atom probe tomography.•Milling the powder for 10h leads to nanostructuration and partial oxidation.•Annealing the milled powder leads to enrichment in Al of the oxidised regions.•Annealing also leads to the formation of a nanostructured β-Mn3Al2 phase.
The structural changes upon milling and subsequent annealing of a Mn54Al43C3 alloy containing the intermetallic tetragonal L10 MnAl phase (τ phase) as the major phase were investigated by X-ray diffraction and atom probe tomography. The analyses show that milling the starting powder for 10h leads to the nanostructuration of the sample. The milled sample is partly oxidised and contains both non oxidised Mn60±5Al40±5 regions and oxidised regions. Annealing the powder for 1h at 500°C leads to enrichment in Al of the oxidised regions, and to the phase transformation of the non-oxidised regions into a nanostructured β-Mn-like phase with a composition close to Mn3Al2.