Lost-form powder injection moulding - combining additive manufacturing and PIM

Powder injection moulding (PIM) is often characterized by being a process for the mass production of relatively complex parts. When it comes to highly complex parts and lower part numbers, additive manufacturing (AM) is regarded as complementary to PIM. Still, AM processes do not make use of the same material as PIM, or even if, are processed differently, which leads to parts with different properties or the need to adjust processing steps (e.g. sintering conditions). By combining PIM with AM in a sensible way, parts can be realized that make use of the PIM feedstock but have considerably increased complexity and can be produced with cheap moulds, thus enabling an economical production of small series in production quality. To demonstrate this approach, we produced sacrificial mould inserts of a suitable polymer by digital light processing (DLP), placed them in a simple mould, injected a metal-ceramic feedstock and thermally degraded the AM structures prior to the sintering of the powder-containing parts. The design of the AM part and its material properties (strength, thermal behaviour) are crucial for the success of the process. The successful production of metal-ceramic parts verified the applicability of the lost-form PIM process with AM parts.