Application of plasma spraying.

Plasma spraying and characterization of chromium carbide – nickel chromium coatings

Chromium carbide – nickel chromium powder Cr3C2-25wt.NiCr was plasma sprayed by a water-stabilized system WSP®. A series of experiments with variable feeding distance was carried out. Basic characterization of coatings was done by XRD, SEM and light microscopy plus image analysis. Microhardness was measured on polished cross sections. The main focus of investigation was on resistances against w...

Solution and Suspension Plasma Spraying of Nanostructure Coatings

Air-plasma spraying colloidal solutions of nanosized ceramic powders

Coatings prepared from nanosized powders were obtained by spraying ethanol-based colloidal solutions into a plasma plume. The powders investigated included 40 nm γ -Al2O3, 75 nm 8 wt% Y2O3-ZrO2, and 750 nm 25 wt% CeO2-ZrO2. Spray distances from approximately 50 to 63 mm were required to achieve significant coating deposition. As observed in the TEM, the typical lamella morphology of air plasma ...

Plasma spraying of micro-composite thermal barrier coatings

The thermal barrier coatings (TBCs) by gas tunnel-type plasma spraying exhibited ceramic-composite features consisting of a host oxide matrix ceramic with an embedded second phase material. The densities of the composite TBC were found to be higher than those sprayed with 100wt% ZrO2 or Al2O3. In the coatings produced with powder mixtures of 50wt%, the embedded splats are found to have a relati...

Modelling for Thermal Control of Vacuum Plasma Spraying

Vacuum plasma spraying (VPS) is an industrial technique used to coat substrates with a wide range of materials for numerous applications. Historically, vacuum plasma spraying processes have been open-loop processes with, at most, closed-loop control of the spray parameters. Such processes would benefit from closed-loop control as the issues of process repeatability and coating quality could be ...