Elimination of Composition Segregation in 33Al–45Cu–22Fe (at.%) Powder by Two-Stage High-Energy Mechanical Alloying

Abstract

In the present work, complex powder alloys containing spinel as a minor phase were produced by mechanical alloying in a high-energy planetary ball mill from a 33Al–45Cu–22Fe (at.%) powder blend. These alloys show characteristics suitable for the synthesis of promising catalysts. The alloying was conducted in two stages: at the first stage, a Cu+Fe powder mixture was ball-milled for 90 min; at the second stage, Al was added, and the milling process was continued for another 24 min. The main products of mechanical alloying formed at each stage were studied using X-ray diffraction phase analysis, Mössbauer spectroscopy, transmission electron microscopy, and energy-dispersive spectroscopy. At the end of the first stage, crystalline iron was not found. The main product of the first stage was a metastable Cu(Fe) solid solution with a face-centered cubic structure. At the second stage, the Cu(Fe) solid solution transformed to Cu(Al), several Fe-containing amorphous phases, and a spinel phase. The products of the two-stage process were different from those of the single-stage mechanical alloying of the ternary elemental powder mixture; the formation of undesirable intermediate phases was avoided, which ensured excellent composition uniformity. A sequence of solid-state reactions occurring during mechanical alloying was proposed. Mesopores and a spinel phase were the features of the two-stage milled material (both are desirable for the target catalyst).

Rational Design of Hierarchical Alloy-Containing Z-Scheme Catalytic Materials toward Effective Conversion of Nitric Oxide Toxic Species under Mild Conditions

“…65-2023) of (0 0 6), (1 0 2), (1 0 4), (1 0 8), (1 1 0), (1 1 6), and (2 0 0). The Cu–Fe alloy was prepared in full accordance with the methods mentioned in the literature . The peaks of 44.7 and 65.0° were associated with (1 1 0) and (2 0 0) crystallographic planes of Fe (JCPDS no.…”

Powder Metallurgy: Materials and Processing

“…The SI consists of 16 papers (published between 2022 and 2023): a review article [ 1 ], a viewpoint paper [ 2 ], a communication [ 3 ], and thirteen research articles [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. The papers reflect the current trends in the field: the search for new compositions (not investigated previously) of materials and the development of new processing approaches enabling better control and flexibility of the materials’ microstructures, shapes, and architectures.…”

“…The research papers report recent findings in metallic [ 4 , 5 , 6 , 7 , 8 , 9 ], ceramic [ 10 , 11 , 12 ], polymer [ 3 ], and composite materials [ 3 , 13 , 14 , 15 , 16 ].…”

“…The preparation of powders of metallic alloys has been addressed by Petrov et al [ 7 ] and Tikhov et al [ 9 ]. The fabrication of high-entropy alloys via powder metallurgy methods has been presented by Moser et al [ 5 ] and Batraev et al [ 6 ].…”