Metal Jet additive manufacturing uses a process of spreading a thin layer of powdered metal and then printing a binding agent (similar to an adhesive) in the locations that the final part is desired. This layering process is repeated many times to build up the final part. Once the build process is complete the loose powder is separate from the part and recycled for the next build. The part then goes through a heat treatment process to remove the binder and to sinter the particles into a solid functional piece. The heating process is typically performed in a MIM (Metal Injection Molding) sinter furnace at several hundred degrees in an air, inert or hydrogen atmosphere at a slightly negative pressure. The binder in the part will thermally evaporate/decompose into gaseous products and mix with the process gasses as they are evacuated from the furnace. The MIM furnace will usually have a vacuum pump and valve that controls the atmospheric pressure and evacuates the gasses and binder residue. The furnace will also have a trap in the exhaust path to capture the binder used in the MIM process; however, the Metal Jet binder is chemically different enough that it is not efficiently trapped in the same manor that the MIM binder is. The binder can coat and foul furnace component causing failures if present in high enough volumes. We report here a new approach of plumbing the exhaust gas path to capture the Metal Jet binder effectively.
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INC, HP, "METHOD FOR CAPTURING BINDER JET BINDER RESIDUE DURING SINTERING PROCESS", Technical Disclosure Commons, (November 21, 2022)