Chemical synthesis of nanostructured magnetic hardened alloy of the Nd-Fe-B system

Hard magnetic nanopowders of the Nd15Fe78B7 alloy were synthesized from mixtures of Nd, Fe and Fe-B oxides with CaH2 in a hydrogen atmosphere at 800 °C by a reduction-diffusion process. Nd, Fe, Fe-B oxides were synthesized by chemical deposition. The resulting particles had a granular shape with an average size: Nd2O3 — 50 nm, Fe2O3 — 95 nm, Fe3BO6 — 57 nm. The particle size of the Nd15Fe78B7 alloy was 45–140 nm. It is shown that the proposed method is suitable for obtaining nanopowders of hard magnetic alloys of the Nd-Fe-B system.

Study of the influence of quick-hardened alloy on the properties of metal polymers

The article explores the effect of quick-hardened alloy PR-N65X25S3R3 based on nickel, (chemical composition – Ni64,6Cr25C1,2Si2,7B2,5Mn0,2Fe3,8) on the physical and mechanical properties of metal-containing polymers. Carried out tests and results have shown that the use of quick-hardened alloys, which are characterized by a set of unique properties, is appropriate. The developed metal-containing polymers that contain aromatic polyamide phenylone and 5 - 20 wt.% of self-fluxing amorphous alloys PR-N65X25S3R3 are characterized by 2 times greater abrasive wear resistance and better adhesive strength between the components. Due to the use of quick-hardened alloy it was possible to increase theeffective filler content from 15 wt.% to 20 wt.% that will increase the electromagnetic properties of metal-containing polymers.

Characteristics of Powders from Different Aluminum Alloys for Additive Technologies Obtained by Gas Atomization

Selective laser melting (SLM) is one of the additive manufacturing technologies that allows us to produce complex shape metallic objects from powder feedstock. Al-alloys are very promising materials in selective laser melting. In this paper, atomized metal powders of various aluminum alloys are investigated: 1) deformable alloys АК4, АК6; 2) cast alloys АК9ph, АК12; 3) deformable hardened alloy D16. As a part of the work, the particle shape, particle size distribution and technical characteristics of the powders were investigated, and also the compliance of materials with the requirements of additive technologies (SLM) was determined.

Intensification of the recovery of hydraulic equipment parts by iron in the electrolyte flow

The technology of bath-free ironing of parts in an electrolyte flow with simultaneous hydrome-chanical activation of the growing surface is proposed. Its advantages over the traditional type of coating are introduced. The structure, some physicomechanical and operational properties of iron coatings were studied depending on the electrolysis regimes and the composition of electrolytes. The possibility of high-speed electrodeposition of iron with a wide range of physical and mechanical properties is shown. There were shown the electrolysis modes, which make it possible to obtain high-quality strong-adhered pure-iron coatings with a wear resistance several times higher than hardened alloy steels and a precipitation growth rate tens of times higher than with traditional iron-ing. A typical technological process of parts ironing was developed. It was tested on the example of restoration of hydraulic valve spools of agricultural machinery. The design of an installation and an electrochemical cell for ironing the valve hydraulic distributors, providing optimal hydrodynamic conditions when applying coatings to worn surfaces, was proposed. Recommendations for the post-electrolysis treatment of restored parts by iron are given. Bench and field tests of hydraulic valves with remanufactured valves were carried out. They confirmed the results of laboratory studies, and showed that no malfunctions were identified during the operation period. Technical and economic calculations have shown the high efficiency of the proposed technology in comparison with tradi-tional ironing. The introduction of the technology in production will reduce the production area and the time spent on restoring parts by increasing the productivity of the iron process and reducing the number of operations, reducing the cost of materials for preparing electrolytes by reducing the op-eration of anodic treatment and washing, and increasing the reliability of the technology by improv-ing its structural scheme.

Self-toughened high entropy alloy with a body-centred cubic structure

Multi-scale deformation structure & evolution analysis of strong-yet-ductile interstitially hardened alloy, exhibiting a two-step phase transformation and concentration wave strengthening.