The effect of impregnation with nanostructured boehmite on the structure and properties of plasma-sprayed ceramic coatings

It is shown that capillary phenomena can be used to nanostructure ceramic coatings via their impregnation with suspensions based on a nanostructured material. Boehmite with particle sizes of 30–50 nm was used as the nanostructured material. Two methods are suggested. When already-formed coatings are impregnated, the system of interconnected pores between particles is used, with the pores within the particles themselves being closed. If hydroxyapatite particles are impregnated before the spraying, boehmite is more uniformly and to a fuller extent distributed within the plasma-sprayed coating. In contrast to the first method, a coating is nanostructured in this case both within hydroxyapatite particles and on their surface. The adhesion increases from 8.4 to 17.1 MPa upon nanostructuring.