Practical Production Considerations for Positional Parameters in Laser Cladding

  • Program
  • Room 2F East
  • September 13 2018
  • 11:45 am - 12:10 pm

In the laser cladding process, the positioning of the powder focus, laser beam and substrate must be carefully controlled to create a stable clad pool with an acceptable process catchment efficiency. Small changes to the relative position between these three elements can lead to significant differences in the physical phenomena of the process. These small positional differences can be on the order of a fraction of a millimeter and can often be overlooked factors in producing high quality coatings with targeted build ups. This work explored the effect of the nozzle working distance, offset from top dead centre for cylindrical cladding, and bead overlap (pitch) to identify experimentally optimum spatial positioning considering process stability and part cycle times. Scenarios for both inner diameter (ID) and outer diameter (OD) cladding will be presented for nickel-tungsten carbide powders deposited on 4XXX series steels using 1μm fibre laser technology. Limitations between the two scenarios (ID vs OD) will be discussed in terms of proximity of the optics to the live process and the difference between mirror and lens optics for the ID and OD systems respectively. It was shown that with specific spatial parameter combinations that reductions of up to 30% of part cycle times were possible. In addition, industrially identified process windows for laser power, travel speed, and powder feed rate could be extended for improved catchment efficiency.