Innovations in Micro Metal Injection Molding Process by Lost Form Technology
Abstract: This study aims to develop the manufacturing method of micro-structured parts by the metal powder injection moulding (MIM) inserted sacrificial plastic moulds which were prepared by thermal nanoimprint lithography (NIL). In this process named NIL/μ-SPiMIM, the feedstock composed of nano-sized copper powder and polyacetal-based binder adequately prepared was moulded into polymethylmethacrylate film with fine line and space pattern structures. After the film was removed by organic solvent,molded partsweredebindedin vacuum and oxidized in atmosphere, followed by sinteringin a reductive gas atmosphere. The filling of feedstock into micro-channelsand debinding-sintering conditions were optimized. The microscopic transcriptional property in molded and sintered parts was evaluated by cross-sectional SEM observation. The experimental results revealedreasonable evidences using nanopowder could sinter at very low temperature with keeping the fine shapes.It can be concluded that the manufacturing method ofNIL/μ-SPiMIM has great potential to produce precisely metallic parts with a single-digit micrometered structures.