Flame spraying: easy to automate

Flame spraying is a thermal spray coating process. It produces high-quality surface coatings using heat to melt a spray coating material. It is a cost-effective option when you would like to apply metallic or ceramic coatings in a less demanding environment, and for large and complex areas and structures. Flame spraying is used to obtain good wear resistance and excellent impact resistance.

The flame spraying process consists of two steps. First, powder is applied by a thermal spraying gun. Second, the deposit is fused with a fusing torch. The powder is then fed into an oxy-acetylene or oxy-hydrogen gun by injection and projected towards the surface at high speed. The hot particles flatten on impact and interlock both with the base material and each other, thus forming a mechanical bond.

This is followed by a fusion treatment to obtain a dense and well-bonded coating on the surface. The applied coating is heated to a temperature of between the solidus and liquidus temperature - around 1,000 °C.

Typical shrinkage of 15 - 20% occurs during fusing when the melt fills the gaps between the particles.

Typical working range

• Deposition rate: 1-9 kg/hour
• Deposition thickness: 0.1 - 3 mm
• Hardness: 38 - 61 HR

Benefits

• Simple to use: only two steps (see above)
• 0.1-3 mm thickness
• Smoother surface than wire

Troubleshooting