Aluminium Sintered Powder

This mottled cylinder of aluminium is heavier than you’d expect - aluminium is generally renowned for being a spectacularly light-weight metal. This unexpected characteristic is a bit of a mystery, but probably has to do with the process by which it has been produced. Powder metallurgy is the process of blending fine powdered metals, compacting them into a desired shape, and then heating the compressed powder in a controlled atmosphere until its particles adhere to each other (sintering). This additive manufacturing technique has been particularly useful as it allows for the making of parts with very little scrap, and usually requires less energy than conventional processing techniques, as the sintering furnace is heated to below the melting point of aluminium. Sintered aluminium powder alloys can have properties quite different from those of aluminium fabricated by conventional casting techniques. The powder sintering process can be controlled in ways that enhance properties like strength, resistance to corrosion and high temperatures, and electrical and thermal conductivity. The porosity and density of the material can also be controlled, depending on the sintering practices and the composition of aluminium and alloying metal powders used.