Suspended powder feeding plasma spraying

       

Suspension powder-feeding plasma spraying is a new type of spraying technology that can directly spray nano-powders and can form ultra-thin nano-coatings by using liquid-feeding powder-feeding methods. The particle radius of traditional non-agglomerated spray powders must be greater than 10µm, and the coating thickness is generally greater than 125µm. Suspension plasma spraying uses liquid material as the medium, uses a dispersant to disperse the particles in the liquid material (the liquid material is generally alcohol) to form a suspension, and sends the suspension into the plasma arc through the liquid material powder feeder. It evaporates rapidly, and the powder in the solvent is heated by the plasma arc to melt and spray onto the substrate to form a coating. This method overcomes the limitation of the radius of sprayed particles, and not only realizes the direct spraying of non-agglomerated nanopowders, but also enables the preparation of ultra-thin coatings with a coating thickness of only 25 µm.

Figure 8 Schematic diagram of suspended powder feeding plasma spraying