Thermal spray processes are ways to coat surfaces by spraying melted or heated materials onto them. These coatings can protect against wear, corrosion or heat. Different thermal spray methods use different temperatures and techniques to apply the coating, making each one useful for specific jobs. Here we share five thermal spray processes and their benefits.
1. Flame Spray
Flame spraying uses a torch that burns at about 3,000°C to melt coating materials. It’s an affordable and portable method. Because of its simplicity, it’s often used for protecting metal surfaces from rust and for fixing worn parts.
2. Arc Spray
Arc spraying melts metal wires by creating an electric arc, reaching temperatures around 4,000°C. This method produces coatings quickly and with fewer pores, making the surface stronger. Once melted, the metal is blown onto the surface using a compressed air jet, forming a coating that solidifies quickly. This process creates a high deposition rate, meaning it can cover large surfaces quickly. The resulting coating has low porosity, which means fewer tiny air gaps, making it stronger and more corrosion resistant. It’s commonly used on structures like bridges and offshore platforms.
3. Plasma Spray
A thermal plasma spray, as shown at www.poeton.co.uk/surface-treatments/thermal-metal-sprays/plasma-coatings/, heats materials up to 15,000°C using a plasma jet, which is created by passing an electric current through a gas like argon, nitrogen, or hydrogen.. This creates very dense and high-quality coatings. Because of its precision, plasma spray is ideal for tough jobs like coating turbine engine components, jet engine nozzles, medical implants – like artificial joints, and semiconductor parts.
4. HVOF High-Velocity Oxygen Fuel Spray
HVOF sprays materials at about 3,000°C but with much higher speed. This results in coatings that are very dense and stick strongly to surfaces. It’s perfect for applications that need wear-resistant layers, such as machine parts.
5. Cold Spray
Unlike the others, cold spray doesn’t melt the material. It sprays particles at high speed below their melting point. Because it doesn’t involve heat, cold spray is ideal for materials that could be damaged by high temperatures. It’s useful for delicate electronics and other sensitive components.
