In 2021, Solar Atmospheres of Western PA reported it was retrofitting a vacuum furnace for use in a new metal injection molding (MIM) and additive manufacturing (AM) binder-removal technology application. The goal was to build a vacuum sintering furnace with a hot zone and pumping technology that would minimize and target the deposit of detrimental binders evaporating out of MIM and AM parts. The furnace has been in production for over a month and produced multiple high-temperature sintering cycles with positive results.
The hot zone, after repeated 2400°F sintering cycles, remains clean. The problematic binders coalesced exactly where they were targeted to consolidate – within a separate heated pumping port while keeping the primary pump and booster uncontaminated. In addition, the MIM parts were extremely bright and met their critical density and dimensional requirements.
The anticipated maintenance savings on this furnace versus processing sintering and AM work with binders in a traditional vacuum furnace will be considerable. Processing this job in a conventional vacuum furnace required a scheduled monthly shutdown. Solar’s maintenance team had to extract the hot zone, replace the ceramics, clean or replace the power feedthrough terminals, scrape the cold walls, clean the diffusion pumps and scour all the pumping-system pipes. The added labor and material costs coupled with the lost production time and degradation on the life of the hot zone cost the company more than $180,000 per year. The projected maintenance costs on this newly designed sintering furnace will be $10,000 per year.