Powder metallurgy has been around for quite some time and has already made its mark in the most demanding sectors (medical, aviation, oil and gas, etc.). Partly due to the emerging 3D printing, however, metal powder is increasingly coming within the reach of traditional means of production and is even succeeding in regaining ground on components that could previously only be made with sustainable plastics and plastic injection moulds.
In terms of technology, the design of these molds can best be compared with plastic injection moulds. Metal powder with binder is injected into a mold under high pressure. In contrast to plastic injection moulds, no temperature is used to transfer from feedstock to a final product, but the powder is mechanically (isostatically) compacted under pressure. The component that comes out of the mold is called ‘green product’ in technical jargon. After decomposition, a so-called ‘brown product’ is formed. After the decomposition step, the product is sintered to its final structure. A good mold for MIM production takes into account the different steps after forming the green product. Intensive cooperation between the mold builder and the injection molder is required to achieve a satisfactory product.
