3D printers now being able to work with materials such as titanium, stainless steel, aluminium etc have positioned the technology as a possible transformative game changer.
Very fine metal or ceramic powder is mixed with a thermoplastic polymer (known as the binder) to form a homogeneous mixture of ingredients. The mixture or feedstock is made into granulated pellets and directly fed into the injection machine.
During injection, the feedstock is heated and injected into the cavity of the mold. This allows the desired shapes and geometries to be formed. The molded part is known as the green part.
The polymeric binder is removed thermally via the debinding process. The green part is subjected to the debinding process at a high temperature while maintaining its relative size and shape. The brown part consists of a powder skeleton that is brittle and porous.
The final stage of the PIM process is sintering. During sintering, the brown part is heated to below its melting temperature. As sintering progresses, density increases, pores are eliminated and the part shrinks to achieve a dense and near-net shape component.
