Parts using powder metallurgy technology have unique chemical composition and mechanical and physical properties, and these properties cannot be obtained by traditional melting and casting methods. The use of powder metallurgy technology can directly produce porous, semi-dense or fully dense materials and products, such as oil-bearing bearings, gears, cams, guide rods, tools, etc., which is a cutting process with little or no cutting.

(1) Powder metallurgy technology can minimize the segregation of alloy components and eliminate coarse and uneven casting structures. In the preparation of high-performance rare earth permanent magnet materials, rare earth hydrogen storage materials, rare earth luminescent materials, rare earth catalysts, high temperature superconducting materials, new metal materials (such as Al-Li alloys, heat-resistant Al alloys, super alloys, powder corrosion-resistant stainless steel, powder High-speed steel, intermetallic high-temperature structural materials, etc.) play an important role.

(2) A series of high-performance non-equilibrium materials, such as amorphous, microcrystalline, quasicrystalline, nanocrystalline and supersaturated solid solution, can be prepared. These materials have excellent electrical, magnetic, optical and mechanical properties.

(3) It can easily realize multiple types of composites and give full play to the respective characteristics of each component material. It is a process technology for low-cost production of high-performance metal matrix and ceramic composite materials.

(4) It can produce materials and products with special structures and properties that cannot be produced by ordinary smelting methods, such as new porous biological materials, porous separation membrane materials, high-performance structural ceramic abrasive tools and functional ceramic materials.

(5) Near-net shape and automated mass production can be realized, so that the resource and energy consumption of production can be effectively reduced.

(6) It can make full use of ore, tailings, steelmaking sludge, rolling steel scale, and recycling scrap metals as raw materials. It is a new technology that can effectively regenerate and comprehensively utilize materials.　　 Many of our common machining tools and metal abrasives are manufactured by powder metallurgy technology.

The production process of powder metallurgy

(1) Production of powder. The powder production process includes steps such as powder preparation and powder mixing. In order to improve the moldability and plasticity of the powder, plasticizers such as engine oil, rubber or paraffin are usually added.

(2) Compression molding. The powder is pressed into the required shape under the pressure of 15-600MPa.

(3) Sintering. It is carried out in a high-temperature furnace or vacuum furnace with a protective atmosphere. Sintering is different from metal melting, at least one element is still in the solid state during sintering. During the sintering process, powder particles undergo a series of physical and chemical processes such as diffusion, recrystallization, fusion welding, compounding, and dissolution, and become metallurgical products with certain porosity.

(4) Post-processing. In general, the sintered parts can be used directly. But for some parts that require high precision, high hardness and wear resistance, post-sintering treatment is required. Post-processing includes precision pressing, rolling, extrusion, quenching, surface quenching, oil immersion, and infiltration, etc.