Influence of Spraying Power and Distance on Porosity and Microhardness of Plasma Sprayed TiO_2 Coatings

摘要

The influence of the two deposition parameters on microstructure, and microhardness of plasma sprayed TiO_2 coatings were investigated. It was found that a higher spraying power and a shorter distance resulted in a lower porosity and a higher microhardness for the coatings. The anisotropy on the microstructure and microhardness of TiO_2 coatings was also found. The denser microstructure is attributed to the higher degree of melting and higher velocity of the TiO_2 powders during spraying. The improvement of microhardness is associated with the lower porosity. The difference of porosity and microhardness between surface and cross section resulted from their different microstructures.