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Metal powders
JSC POLEMA, Russia's largest producer of metallic powders, offers a wide selection of powder alloys and pure metals using various production methods: spraying the alloy with gas and high-pressure water, oxides recovery, and mechanical crushing.
The characteristics of metal alloys are developed during the crystallization of molten metals. Unlike cast alloys, alloys produced by spraying a molten metal boast a high level of homogeneity in terms of chemical and phase composition, and a finely dispersed structure. The homogeneous structure is based on the fact that before the molten metal is sprayed, it is heated until the inherited structure of the solid state of the alloy components is completely broken down, and the molten metal particles, dispersed into drops, crystallize at high speeds, at up to tens of thousands of degrees per second. The gas-sprayed powders are characterized by a spherical particle shape, high fluidity, and microcrystalline structure. When molten metals are sprayed using water, the flow is actually dispersed using heated pressurized vapor formed in the contact zone between the surface of the water and the molten metal. The continuous vapor film significantly slows the speed at which the sprayed drops cool, due to the lower heat transfer by steam. The resulting powders have a rounded or irregular particle shape and a thin dendritic structure, and boast considerably better compactibility than that of gas-sprayed powders.
Recently, JSC POLEMA has been actively applying new technical solutions for gas-spraying alloys that make it possible to significantly improve particle morphology, reduce the number of «satellites», and improve powder fluidity and the quality of hard-face coatings.
Sprayed powders produced by JSC POLEMA are classified into two groups: materials for gas-thermal coatings and powders for use in construction. The first group includes more than 200 brands of hydra alloys for applying coatings using various spraying and deposit methods: self-fluxing nickel, iron and copper alloys, tool steel, high- and low-carbon steels and alloys, corrosion-resistant and heat-resistant steels and alloys, and stannum- and zinc-based composite powders and alloys.
The variety of the materials we offer for coatings are classified for practically all methods of spraying and depositing (high-speed, detonation, gas-fired and plasma spraying, gas-powder, plasma, induction and laser depositing) that makes it possible to solve concrete challenges in surface strengthening and effective protection from wear and corrosion of machine parts and equipment working at high temperatures to the effects of physical stress, abrasive substances and aggressive environments.
The second group - powders for construction purposes - are compacted powders of pure metals (chromium, molybdenum, tungsten, nickel, and titanium), copper-based alloys (bronze, brass), stainless steels, special alloys with high magnetic conductivity (permalloys), and materials for bead-blasting treatment of part surfaces (tool steels). Powders in this group are used to produce flat stock, rods and forgings made from non-ferrous and high-melting metals, tools, sintered and deformed parts, composite materials used in electrical engineering, electronics, instrumentation, mechanical engineering, the air and space industry, nuclear energy, transportation, manufacture of filters and gas absorbers, and in other areas of engineering.