Study of Al–Cu–Fe–Ti–Cr–Si powders for thermal spraying produced by mechanochemical synthesis and subsequent annealing

• Published in: Powder metallurgy and metal ceramics 2009-09, Vol.48 (9-10), p.514-521
• Main Authors: Borisova, A. L., Adeeva, L. I., Tunik, A. Yu, Karpets, M. V., Rupchev, V. L., Burlachenko, A. N.
• Format: Article
• Language: English
• Subjects: Alloys; Aluminum; Annealing; Approximants; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Chromium base alloys; Composites; Diffraction; Glass; Materials Science; Metallic Materials; Metallurgy; Natural Materials; Powder metallurgy; Synthesis; Titanium base alloys
• ISSN: 1068-1302; 1573-9066
• DOI: 10.1007/s11106-010-9161-4

The paper examines the phase transformations of composite powders based on Al 63 Cu 25 Fe 12 that contain alloying elements (Ti, Cr, Si in the ratio AlCuFe : TiCrSi = 75 : 25). The powders are produced by mechanochemical synthesis and subsequent thermal treatment. Amorphous and crystalline powder mixtures form during synthesis; their annealing results in multiphase structures consisting of α, β 1 , and β 2 phases. High-temperature x-ray diffraction has revealed an α-phase between 700 and 900°C. The new α-phase should be regarded as a 1/1 approximant of the nonequilibrium quasicrystalline phase. The maximum content of the approximant phase (68 wt.%) is observed after five-hour synthesis and subsequent annealing (T = 700°C, τ = 2 h) of pressed powders, microhardness of the particles reaching 8900 MPa.