Abstract

The powder injection molding (PIM) process offers a fabrication technology for making parts by metal powder injection molding (MIM) and/or ceramic powder injection molding (CIM). It consists of four main steps: mixing of feedstock, shaping by injection molding, debinding, and sintering.

PIM offers considerable economic efficiency in large-scale manufacturing and allows the production of complex shaped devices with usually no postprocessing. A further attraction is the wide range of materials that can be utilized, for example, different kinds of steels (such as 316L or 17-4PH), copper, titanium, refractory metals, hard metals, oxide and nitride ceramics, and so on.

Typical PIM products reveal densities of 95–99% of the theoretical values, maximum part weights of 1 kg (may be higher in certain cases), and wall thicknesses up to more than 20 mm.

Development of the so-called MicroPIM process can help large-scale manufacture of metal and ceramic microcomponents. Presently, the smallest dimensions achievable are less than20 μm of part thickness or minimum structural details of less than 10 μm. Theoretical densities of up to 99% for ceramics have been achieved, while the nominal sizes of the final parts have reached tolerance levels of ±0.1–0.5%.

Current investigations deal with the development of simulation programs taking into account specific features of multimaterial systems as well as the particular effects that occur when processing highly powder filled fluidics.

For the reduction of mounting costs and production of highly integrated devices, two-component injection molding (2 C-PIM) is under advanced development. By the adjustment of the feedstock and sintering parameters, immovable or movable bonds can be generated.