Abstract
Cold spray is a reduced temperature, supersonic thermal spray process that is increasingly being used to perform repairs on high value components. In this case, a valve actuator internal bore sealing surface was repaired on an aluminum 6061 hydraulic valve body using high pressure cold spray. Corrosion damage to non-critical surfaces was also repaired, allowing the part to be returned to service. The VRC Gen III high-pressure cold spray system was used to deposit gas atomized 6061 aluminum powder. The internal bore surfaces were approximately 100 mm in diameter with a depth of nearly 200 mm, and were sprayed using a 45-degree nozzle 65 mm in length. The minimum required adhesion strength on critical surfaces was 69 MPa. The average adhesion strength was 71.4 MPa, with glue failures on ASTM C633 bond test specimens.
