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Laser Cladding |
What is Laser Cladding ?
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Laser cladding falls into the group of processes commonly known as hard-facing. The laser cladding process is a method of applying a fully dense, metallurgically bonded and virtually pure coating which can be used to increase the wear resistance, corrosion resistance or impact performance of metallic components. In some cases, all three of the properties can be improved. The process utilises a precisely focussed high power laser beam to create a weld pool into which a metallic powder is applied. The powder, which is carried by a stream of inert shielding gas, is blown coaxially through the laser beam. The highly accurate nature of the laser beam allows fully dense cladding with minimal dilution (<5%), yet with a perfect metallurgical bond. Numerous coatings can be applied, the composition of which can be designed to combat the failure mechanisms associated with each component.
Fundamentals Of Laser Cladding
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- Typical single layer thickness: 0.2 - 2.0mm (multiple layers possible)
- Heat input to part: low to moderate
- Dilution with substrate material: variable with parameters but can be <5% gives a very pure coating with the desired coating properties.
- Adhesion: full metallurgical bond
- Density: fully dense (<0.1% porosity)
- Coating materials: WC/Ni alloys, Ni alloys, WC/Co alloys, Stellite 6, Inconel625, FeCrB,
Comparison Of Coating Processes
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The following table gives a broad comparison of coating processes. The data shown is based on typical applications and parameters. There can be exceptions to the below data, based on specific applications and parameters.
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HVOF Thermal Spray |
PTA |
Laser Cladding |
Heat source |
Flame (liquid or gas) |
Electric arc |
Laser beam |
Coating thickness (typical) |
0.05 – 1mm |
0.5 – 5mm |
0.2 – 2mm |
Typical Deposition rates |
≤ 5 kg/hr |
≤ 10 kg/hour |
≤ 5kg/hr |
Dilution |
0 |
5-15% |
≤ 5% |
Type of bonding |
Mechanical |
Metallurgical |
Metallurgical |
Bond strength |
≤ 80 MPa |
≤ 800 MPa |
≤ 800 MPa |
Heat input |
Low – medium |
High |
Low - medium |
Porosity |
≤ 1% |
< 0.1% |
< 0.1% |
Comparative capital cost |
Medium |
Low |
High |
Comparative running cost |
High |
Medium - Low |
Low |
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Typical Applications (Coating Materials)
- Down hole stabilisers (WC/Ni)
- High temp process rolls, hardness & corrosion resistance, valve lips and seats (Cobalt 6)
- Valve balls/seats, process rolls, waste incineration boiler parts, oil refinery process plant (NiCrMo)
- Coal and ore crushing hammers / wear plates / sand valves (WC/Ni)
- Valve balls/seats, process rolls, boiler components, waste incineration boiler parts, hydraulic rods, down hole stabilisers (FeCrB)
Laser Head
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Part No. |
Description |
MET-CLAD HEAD |
MET-CLAD laser cladding head |
Technical Overview
- Powder feed through conical co-axial ports to maximise precision, quality and efficiency of cladding.
- Laser focus point by simple adjustment in the head.
- Laser / powder feed head easily interchanged.
- Water cooled parts to ensure longevity.
- Optional internal camera to view the weld/clad region during processing.
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