Metal injection molding (MIM) is a low cost method of fabricating small and complex parts that have mechanical properties similar to those of the wrought version of the alloy, about 96-97% for both Inconel 718 and 17-4 stainless steel. The process involves mixing metallic powder with plastic binders, injecting the mixture into a mold, and then chemically de-binding the mixture and sintering the product in a vacuum furnace. Parts made using this process have good dimensional stability, typically less than 0.25% of linear distance, and 95-98% of the theoretical density of the alloy used. This process reduces, or eliminates, both machining costs and machining-related scrap, with cost reductions of up to 70% being attained. The process is best suited to large-scale production runs.

Boeing Phantom Works is currently investigating applications of this process to a variety of aircraft mechanisms and systems programs. There are potential applications for features such as seat & tray mechanisms, and cargo floor mechanisms. Boeing Phantom Works is determining the capabilities of several US MIM suppliers, in a static properties test program using supplied MIM test specimens. This program was completed in June 2003. Boeing has also initiated a study with the University of Sheffield, England to determine the fatigue properties of parts made using this process.