High power diode laser cladding

The characteristics of new high power diode lasers make them ideal for several materials processing operations. One such operation being laser cladding. A 1.2 kW diode laser has been used to successfully clad ferrous metals with 25% Cr, 10% Ni deposits. The effect of laser power, cladding speed, powder delivery rate and method were investigated. The resulting clad layers were examined and characterised using optical and electron microscopy, hardness testing and x-ray analysis in order to determine the quality of the clad. Results indicated that extremely good clad layers were produced which were free from porosity and well bonded to the substrate material. In a single pass, the clad area was also significantly larger than those produced by other types of laser. Additionally, the high quality of the clad was also indicated by the very low levels of dilution of clad material and the fact that the metallurgical structure of the clad was finer than that achieved with conventional cladding operations. The overall conclusions of this work were that cladding with the high power diode laser is an extremely effective process, even compared to other laser cladding alternatives, and that large area, high quality clad deposits can be successfully deposited.