AFSD for In-Situ AM-2 Matting Repair

IERUS Technologies proposes to additively repair AM-2 matting using the additive friction stir deposition (AFSD) process. The AFSD process is based on the principle of friction stir processing, it is a solid-state, layer-by-layer deposition process that incorporates severe plastic deformation and frictional heating to fabricate near-net shape components from solid feedstock. In AFSD, the feedstock is pushed through a hollow rotating tool onto a substrate. The friction between the rotating tool and the substrate surface produces enough frictional heat to plastically deform the feedstock, which is then deposited on the substrate surface. Unlike beam-based AM processes, AFSD creates fully dense components without melting and with no porosity. Importantly, the most attractive features of the AFSD process are its capability to rapidly deposit materials and to locally control microstructure thus creating location-specific properties. The quality of the desired microstructure and fabrication rates are established through flexible process parameters such as spindle geometry, spindle speed, deposition rate, and substrate traversing rate. Maximum temperatures during this process are maintained well below the liquidous state (Td < Tm) of the respective deposited material, preventing phase transformation during the deposition. The lower temperatures during deposition allow for a lower amount of distortion for the substrate, in comparison to fusion-based additive manufacturing techniques.