Powder metallurgy is the process that creates metallic parts by mixing powdered metals into the desired shape and then heating the build. The process is divided into four steps: producing the powder, mixing the powder, compacting it and sintering it.
The earliest known use of powder metallurgy was in Egypt in around 3000 BCE. Powder metallurgy allows for controlling physical characteristics like porosity, complex shapes, wear resistance, surface finish and hardness. Producing the powder is done by electrolytic deposition, chemical reactions, grinding and comminution. Products that are made using powder metallurgy include magnets, filters for gases, bearings, microwave ferrites, electrical contacts, spacecraft heat shields, metal glasses, friction brake linings and light bulb filaments. Three-dimensional printers also use powder metallurgy to print metals.