All thermal spraying processes rely on the same principle of heating a feed stock, (Powder or Wire) and accelerating it to a high velocity and then allowing the particles to strike the substrate. The particles will then deform and freeze onto the substrate.
The coating is formed when millions of particles are deposited on top of each other. These particles are bonded by the substrate by either mechanical or metallurgical bonding.
The Process
1. The first step of any coating process is surface activation. This is done by cleaning and grit blasting the surface to be coated. Masking techniques are normally adopted for components that only need specific areas coated.
2. The second step is to melt the material, this is done by introducing the feed stock material into the hot gas stream. The hot gas stream is produced by either chemical reaction (Combustion) or by physical reaction (Plasma).
3. Thirdly the particles are then accelerated to the substrate by the gas stream and deform on impact to form a coating.
4. Finally the coatings are inspected and assessed for quality by either mechanical or microstructural evaluation.
Tidak ada komentar:
Posting Komentar