Laser Cladding

Laser Cladding

All laser cladding operations are fully automated, ensuring accurate and repeatable applications of the weld overlay. Laser cladding offers precise control, coordinated by a single computer system.

Common Applications

  • Hard valves and seats
  • Down-hole tools for oil and gas drilling
  • Agricultural size-reduction tooling
  • Extremely high-wear application

Laser application of metallic overlays to metallic substrates offers properties similar to overlays applied by traditional welding methods but with substrate metallurgy effects more akin to sprayed and fused coatings. The result is a true metallurgical bond of overlay and substrate with minimal dilution and low heat-affected zone (HAZ). Laser-applied overlays do not require masking for precise deposit geometry, and they can be tailored for nearly any substrate/overlay pairing.

Method

Laser-applied overlays are produced by locally heating the substrate metal to a molten state using a tightly controlled beam of laser energy, and then introducing a feedstock of the overlay material in powder or wire form. The melt pool produced by the defocused laser beam absorbs the melted feedstock, and, as the beam and powder injection are moved away, the material rapidly solidifies, producing a fully dense weld bead. The welding apparatus is attached to a motion control system—either a five-axis CNC device or a six-axis robotic arm—which can be programmed to precisely guide the tool over complex surfaces, yielding a uniform overlay thickness over nearly any outer surface geometry. Monitoring of the tool speed over the surface allows the system to accurately throttle laser power and powder parameters to ensure uniform coating properties despite acceleration and deceleration of the tool by the motion control system.

Practice

Due to the precise control of the laser energy at the weld pool, overlays can be tailored to provide optimal deposition efficiency, thickness, and/or HAZ. Typical single-pass thicknesses can be in the range of .015” to .060”, though other dimensions are possible. Geometric accuracy of the overlay’s dimensions can be within a few thousandths of an inch, depending on the shape of the weld border. Other methods can be used to control the surface finish of the overlay after application.