Powder metallurgy, as a new type of modern industrial technology, has been widely used in all walks of life. Powder metallurgy, as a continuously developing industry, has continuously increased its knowledge reserves and technical capabilities. And powder metallurgical materials have unique chemical composition and physical and mechanical properties that can not be obtained by traditional casting processes. What is the specific nature of powder metallurgical materials?
1, powder metallurgy friction reduction materials: also known as sintering friction reduction materials. It is prepared by immersing the lubricant in the pore of the material or adding or subtracting agent or solid lubricant in the composition of the material. The friction coefficient between the surfaces of materials is small, and the service life is long and the reliability is high under the limited lubricant conditions. Under the condition of dry friction, the lubricant contained by itself or the surface layer has self-lubricating effect. Widely used in the manufacture of bearings, support Bushing or end surface sealing.
2, powder metallurgy porous materials: also known as porous sintering materials. Made from spherical or irregularly shaped metal or alloy powder formed and sintered. The internal pores of the material crisscross and cross each other. Generally, there are 30 % to 60 % of the volume porosity, and the aperture is 1 to 100 microns. Through the performance and thermal conductivity, good electrical conductivity, high temperature, low temperature, thermal shock resistance, corrosion resistance media. For the manufacture of filters, porous electrodes, fire extinguishing devices, anti-freeze devices, etc..
3, powder metallurgical structural materials: also known as sintering structural materials. Can withstand tensile, compression, distortion and other loads, and can work under friction and wear conditions. Due to the existence of residual pores inside the material, its ductility and impact value are lower than that of the casting forgings with the same chemical composition, thus limiting its application range.
4, powder metallurgy friction materials: also known as sintering friction materials. It consists of three parts: matrix metal, lubrication element and friction element. Its friction coefficient is high, it can absorb kinetic energy quickly, braking, transmission speed, and wear are small; High strength, high temperature resistance, good thermal conductivity; Good bite resistance, corrosion resistance, less affected by grease, humidity. Mainly used for manufacturing clutches and brakes.
5, powder metallurgical mold materials: including cemented Carbide, powder metallurgical high-speed steel and so on. The latter has uniform organization, small grains, and no segregation. It is better than the high speed steel cast and has better toughness and wear resistance. The heat treatment is less deformed and has a long service life. Can be used to manufacture cutting tools, molds and parts of the billet.
6, powder metallurgy high-temperature materials: including powder metallurgy high-temperature alloys, refractory metals and alloys, metal ceramics, dispersion reinforcement and fiber reinforcement materials. Turbine discs, nozzles, blades and other high-temperature resistant parts used in the manufacture of high temperature.
The above is about the analysis of powder metallurgical materials, the porosity of powder metallurgical materials can be controlled, the material structure is uniform, and there is no macroscopic segregation(after the solidification of the alloy, there is no chemical composition imbalance caused by the macro flow of liquid alloys at different parts of the cross section). phenomenon), Can be formed at one time.