Engineered Surfaces for Exceptional Performance
Engineered Surfaces for Exceptional Performance

Hard Chrome Replacement Alternatives | MSSA

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HVOF Alternatives to Hard Chrome Plating

The HVOF process has fewer process steps and higher coating rates than that of conventional hard chrome plating methods. HVOF is generally faster, more cost-effective and is known to extend the service lifespan of components all while producing coatings with a strong bond and low porosity.

Reason for use: To replace Hard Chrome plating particularly where environmental pressures have reduced its use.

Coatings Used Include

  • Iron, Chrome, Molybdenum Alloy (Resistant to Wear and Corrosion at temperatures up to 650oC).
  • Nickel, Chrome, Boron, Silicon Hard-facing Alloy (Coatings applied are extremely dense and semi-fused in the as-sprayed state. They offer very good corrosion and acid resistance).
  • Tungsten Carbide, 17% Cobalt Alloy (An exceptionally tough coating with good impact resistance for sliding wear applications).
  • Tungsten Carbide, 10% Cobalt, 4% Chrome Alloy (Corrosion resistant coatings with extremely high resistance to abrasive & sliding wear, widely used in seawater environments).

HVOF benefits over Chrome Plating

  • No plating tanks to maintain.
  • No disposal of toxic solutions.
  • No water treatment plant.
  • No limitation on component size.
  • No heat treatment required.
  • No acid solutions involved, hence no hydrogen embrittlement, thus improved component toughness.
  • Coatings can impart compressive stresses on the substrate, improving fatigue behaviour.
  • Coatings are denser with no crack crazing.
  • Microporosity assists in the retention of lubricating films.
  • Fewer process steps.
  • Improved stock control from in line processing.
  • Low capital investment.
  • Low installation costs.
  • Improved process control.
  • Competitive coating costs.

Process Steps

HVOF Thermal Spray

  1. Degrease.
  2. Gritblast.
  3. Spray.
  4. Finish Grind.

Hard Chrome Plating

  1. Degrease.
  2. Alkaline Wash.
  3. Rinse.
  4. Etch.
  5. Rinse.
  6. Plate.
  7. Rinse.
  8. Dry.
  9. Finish Grind.

Coating Rates

4L Thermal Spraying 

HVOF 4L System

  • Typical Spray Rate of: 4.5Kg/Hour.
  • Resultant Coverage of: 12.5m2/Hour at a coating thickness of 25µm.

Hard Chrome Plating

  • Plating plants usually treat at a rate of 25µm coating thickness per component hour.

HVOF Environmental Benefits

  • No Hexavalent Chrome.
  • No Chemical Solutions to control.
  • No Water Treatment Plant.
  • No Toxic Solutions to be disposed of.
  • Overspray from the HVOF can be recovered and sold as metal scrap.

Industry Applications

  • Aerospace – Actuators.
  • Aerospace – Undercarriage Systems.
  • Automotive.
  • Earthmoving Plants.
  • Petrochemical.
  • Plating Shops.
  • Printing Industry – OEM.
  • Print Machine Repairs.
  • Pump Manufacturers – OEM.
  • Pump Repairs.
  • Textile Machinery.