In situ XRD studies on Al–Ni and Al–Ni–Sr alloys prepared by rapid solidification

• Published in: Journal of alloys and compounds Vol. 464; no. 1; pp. 95 - 100
• Main Authors: Saksl, K., Vojtěch, D., Ďurišin, J.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 22.09.2008; Elsevier
• Subjects: Alloys; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystal structure; Exact sciences and technology; Intermetallics; Materials science; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Quenching; Rapid solidification; Solidification; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; X-ray diffraction; Intermetallics; X-ray diffraction; Rapid solidification; Quenching; Crystal structure; Annealing; Nickel alloys; Structure stability; Intermetallic compounds; Ternary alloys; XRD; Multiphase system; Binary alloys; Strontium alloys; Aluminium alloys; Solid solutions; Pair distribution function
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2007.10.022

In this paper the structure and stability of Al–17 wt.%Ni(Al–17Ni) and Al–17 wt.%Ni–2 wt.%Sr alloys prepared by rapid solidification was investigated by means of XRD techniques. Our work demonstrates that both alloys are crystalline and composed of fcc (Al–Ni) solid solution and orthorhombic Al 3Ni phases. The ternary alloy shows in addition the presence of small amount of tetragonal Al 4Sr phase. In situ XRD experiment demonstrates the stability of the solute solution up to 650 °C, Al 3Ni above 750 °C while Al 4Sr overcomes melting of the major phases at 800 °C. High-temperature structure analysis proved strong bindings between Al and Ni atoms in Al 3Ni phase, corroborating its covalent nature, linear and faster increase of the fcc volume with annealing temperature. The linear correlation between constituting atoms decreases with increase of the temperature. The work also documents the applicability of pair distribution function (PDF) analysis to the study of multiphase crystalline systems.