The use of copper in powder metallurgy

The first application of copper powder is to mix copper and tin powder to make bronze parts. In the early 1920s, metal refining (USMR), located in the caltwater autonomous region of New Jersey, started producing electrolytic copper powder. The factory is small in size and has large cathode groove. During the peak production period, the powder plant produces about 455 tons of copper powder per month. In the mid-1980s smelters and electrolytic refiners were forced to close, and because of the closure of the cartwright plant, there was no production of electrolytic copper powder in the United States, despite attempts by some companies to produce it. Today, electrolytic copper powder is produced in Europe, Japan, Russia, India and South Korea. The electrolytic copper powder particles in the new material of guangdong province are known to have the characteristic of dendritic shape through research. By adjusting the process, the density of pine packing is less than 1 gram/cm3, and the strength of green billet is greater than 35MP. Loose packing density can be increased by adjusting sedimentation process and powder reprocessing.

The copper powder can be produced by water atomization and air atomization process and REDOX process. The physical properties of the atomized powder (e.g., bulk density, fluidity, particle size, and bloom strength) are related to the process conditions such as specific additives, melting temperature, atomizing pressure, reduction temperature, and post-treatment of the powder. The median diameter of powder through REDOX test was 10 microns, the loose packing density was less than 1.5 grams/cm3, and the green density was greater than 20MP. Powder particle size and reduction temperature after atomization are the key factors to determine powder products. The properties of atomized and REDOX powders were found to be basically the same as electrolytic copper powders in application.

The machined self - lubricating copper - tin base oil bearing (with internal porosity) is a unique characteristic of powder metallurgy. Such bearings are sintered to a certain density, and the porosity oil content can be up to 10-30%. Such bearings need to be lubricated periodically to ensure safe operation during the life of the equipment. The self-lubricating bearings were first used in the buick automobile industry in 1920. The use in other industries was considerable and transformed the industry of household equipment. The manufacture of self-lubricating bearings consumes about 55% of the copper powder output. Cu-pb and cu-pb-sn bearings for automotive, turbine, thrust washers and industrial pump equipment. Cast and forged bronze bearings have been replaced by steel-back materials, powder is coated on the steel matrix, and a certain density is achieved through sintering and rolling, with the porosity of the final product less than 0.25%.

By atomizing brass powder and nickel silver alloy powder, the zinc content in brass powder is between 10% and 30%, and lead is sometimes added to improve mechanical properties. Brass powder has been used in locks, instrumentation and driving equipment. Because of its beautiful color, brass is used for decorative metal MEDALS. The 2.6kg brass powder metallurgy component was recently used on the robot arm. Sintered parts with a density of 7.7 g/cm3 have tensile strength of 193MPa and elongation of 14%.

In 2002, according to data from guangdong dahong new material, the use of copper powder in the world is estimated to be between 5.9 and 64,000 tons, that in North America is 22,000 tons, that in Europe is 18,000 tons, and that in other countries 4,500 tons. About 55% copper powder is used in bronze parts, 13% is mixed with iron powder to produce powder metallurgy parts, 12% is used in osmotic sintering powder, 10% is used in brass, 10% is used in other applications such as friction materials, chemistry, w-cu and mo-cu heavy metals, coatings, paints, pastes and inks. A large number of powder metallurgy parts show that the powder metallurgy technology has great potential and creativity in the use of copper base materials.

According to the current development situation, powder with particle size less than 10 microns is suitable for the production of metal powder injection moulding parts. Copper powder can be manufactured into complex shape MIM communication medical treatment, MIM intelligent wear and MIM auto parts through metal powder injection molding process. This product has good electrical and thermal conductivity. We can use high purity copper powder to improve electrical conductivity and thermal conductivity by increasing the final density of the part. Metal powder injection molding process can improve the density of copper powder, the electrical conductivity and thermal conductivity of the product.

More about copper in the field of powder metallurgy, welcome to consult the professional team of guangdong dahong new materials for your answer!