Laser cladding with scanning optics: Effect of scanning frequency and laser beam power density on cladding process

Scanning optics is an effective way to manipulate a laser beam for laser cladding. The numerical adjustment of the scanner gives a great deal of flexibility to the cladding process. However, the effect of the scanned beam on the cladding process itself has not been studied very thoroughly so far. This study concentrates on explaining how the scanning frequency and power density of the laser beam affect the stability of the cladding process. The results showed that both of these factors significantly influence the process stability and the outcome of the cladding process. If the local specific energy input was over 2.46 J/mm2, the process was noticed to be unstable. This limit was cross when scanning frequency was under 40 Hz. Power density's limit value for stable process was found to be 191 kW/cm2 and higher power densities than this was found to produce unstable process. If the cladding process was found to be unstable, dilution increased significantly and process started to resemble more laser alloying.