A New Method of Selective Laser Cladding

Abstract

A new approach to selective laser cladding using conical laser beams has been elaborated. The initial round laser beam is divided into two or more circular beams with regulated distribution of the laser power between them. The circular beams are converted into conical beams that are focused separately on the surface and on different areas of the deposited material for their efficient heating. The delivery of laser energy into the powder stream is very effective because it provides a complete uniform absorption of laser energy in a dense powder stream (10⁴–10⁶ cm^–3). Under wire deposition, substrate heating reduces residual stresses due to temperature gradients and compensates for heat loss from the deposition zone by thermal conduction. The required power density for melt contact formation is significantly reduced.