Abstract
The effects of substrate temperature during the flame spraying, addition amount of Nd2O3 to BaTiO3, and heat treatment on the structure of the semi-conductive coatings were investigated by means of X-ray diffraction, X-ray microanalyzer, thermal analyzer, and electron microphotography.
As the results, the difference in the effect of substrate temperature was found between with and without the additive. When the additive was not used, the crystal growth was accelerated and the glassy material content was reduced with the rise in the substrate temperature. On the contrary, when the additive was used, the crystal growth was retarded and the glassy material content was increased with the rise in the temperature.
There was a close relationship between PTC (Positive Temperature Coefficient) and crystal size or amount of glassy material.
