Study of Forming Efficiency by Real-time Correction of Head Nozzle Height in Directed Energy Deposition

Laser metal deposition is of two types: powder bed and metal deposition. Either method is expected to be a breakthrough in innovative design and manufacturing technology development because both methods can form shapes that cannot be formed by conventional removal processing. One metal deposition method is directed energy deposition (DED), in which a laser irradiates the target position on the metal layer to melt it, and metal powder is supplied to the target position to perform molding. DED is expected to produce large parts and repair molds. However, as the lamination mechanism is not sufficiently clarified, relationships between process parameters, material properties, molding accuracy, and molding efficiency are not clear, making stable molding difficult [1]One obstacle to stable molding is that the distance between the head nozzle that supplies the metal powder and the molten pool cannot currently be kept constant. In this study, we measure the distance between the head nozzle and the molten pool using a triangulation method, propose a method to control the position of the head nozzle to keep the distance constant, and experimentally verify the method's usefulness.