Combustion powder spraying
Combustion powder spraying is one of the processes in the thermal spraying category. In this process, the powder material is fed through the gun using a carrier gas and injected centrally into a burning gas-oxygen mixture. This melts the powder particles transported to the treated part to form a protective coating. The technique differs from other thermal spraying techniques because of the possible two variants. These are the 'cold' and the 'warm' spraying process.
The ‘cold’ combustion powder spraying process
In the 'cold' spraying process, the temperature of the base material will remain between 50 and 200 °C, so there is no chance of structural change and deformation. This makes this process is very suitable for repair applications. But there are other advantages to the 'cold' form of combustion powder spraying:
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- Fully dense-coating microstructure
- High coating hardness
- Excellent wear and corrosion resistance
- Coatings are metallurgically bonded to the substrate
- Coatings can be ground to tight dimensions with a good finish
The ‘warm’ combustion powder spraying process
In the "warm" spraying process, the spray process is followed by a post-coat fuse. The workpiece is heated to approximately 1100 °C, whereby the applied coating melts onto the base material. The melting (diffusion) creates a solid metallurgical bond to the substrate.
The spraying powders used for this purpose are the so-called self-fluxing alloys. These powders have nickel or cobalt as base material. Tungsten carbides can be added for an even more wear-resistant coating. The main features of this 'warm' form of autogenous powder spraying are:
- Metallurgical bond to the substrate
- Resistant to the line, impact and point loads
- Homogeneous and closed structure
Combustion powder spraying coatings
The material of the powder particles that are melted to apply the coating may vary depending on the application. A combination of different materials is often made to achieve the ideal coating for your application. Would you like to know more about a material? Click on the material for more information.
- Self-fluxing alloys
- Nickel base alloys (Colmonoy types)
- Cobalt base alloys (stellite types)
- Various stainless-steel alloys (Self-fusing alloys)
- Cermets, carbides (tungsten carbide)
Is combustion powder spraying the right solution for you?
Would you like to know more about combustion powder spraying by Sietzema Techniek? We’re happy to tell you more about this solution. With our many years of experience, we can advise you on the best coatings for your application. Please feel free to contact us for more information.
