ELECTROCHEMICAL SURFACE FINISHING OF COMPLEX ADDITIVELY MANUFACTURED PARTS

This paper will discuss recent developments toward the demonstration of electrochemical processing conditions and tooling that enable complex components to be produced by additive manufacturing approaches to be finished or polished. Unlike conventional machine finishing processes, where surfaces are accessible, one benefit of this approach enables parts built with internal channels that maybe inaccessible to machining can be finished to the desired level. Furthermore, this paper is focused on a pulse/pulse reverse electrofinishing process (that eliminates the use of hazardous chemicals) developed by Faraday Technology of various material groups including but not limited to titanium alloys, tantalum alloys, nickel alloys, stainless steels, niobium, and molybdenum alloys. This approached enables the use of low cost, scalable, user friendly water based non-hazardous electrolytes and improved process control and efficiency. Furthermore, we will specifically discuss techniques in electrofinishing AM / HIPped parts and the design of tooling that enables complex components / passages to be finished to meet the required surface specifications. Finally, this discussion will specifically include limitation and advantages of this approach and demonstrate the potential to achieve working shrouded impellers.