Microstructure and electrical properties of coatings of the Cr2O3-TiO2 system

In the present work the preparation, microstructure, hardness and resistivity of APS- and HVOF-sprayed coatings from all regions of the Cr2O3-TiO2 phase diagram were systematically investigated. Apart from commercially available feedstock powders on the Cr2O3-rich side, five agglomerated and sintered experimental powders on the TiO2-rich side were used. Both spray processes produced homogeneous and lowporosity coatings. Considerable changes in the phase compositions occurred as a result of the spray processes. For coating hardness and electrical resistivity a dependence of the properties on Cr2O3 content was found. The coatings have great potential for application as ceramic coatings with excellent hightemperature stability and electrical conductivity.