High-Velocity Air Fuel Spraying

• 02 Feb 2024

In the quest for eco-friendly alternatives to hard chrome plating (HCP), scientists from the International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), an autonomous institution of the Department of Science and Technology (DST) affiliated institution, have pioneered a technique called high-velocity air fuel spraying (HVAF).

• This method holds the potential to transform the landscape of surface coatings, offering a safer and more efficient solution for car parts, tools, and kitchen utensils.
  • HCP is an electroplating process in which a layer of chromium is applied to a surface to improve corrosion and wear resistance, reduce friction, and extend the life of parts used in extreme working environments.
  • HCP contains carcinogenic substances prompting the search for a safer alternative.
• HVAF spraying involves low temperatures and high particle velocities, allowing the deposition of coatings using finer-sized powders (5-15 µm).
  • Scientists synthesized thin hard coatings of a composite alloy of Tungsten, cobalt, and chromium by high-velocity air fuel spraying.
• HVAF-sprayed coatings have shown superior sliding wear performance and corrosion resistance compared to conventional HCP.
  • The technique reduces the need for grinding and polishing operations, leading to cost savings in processing and raw materials.
• The new technique can be a better alternative to HCP for heavy-load applications like hydraulic shafts, valves, piston rods, and balls.

Read more: Nickel Alloy Coatings