Ceramic on Metal Substrates Produced by Plasma Spraying for Thick Film Technology

Abstract

The arc plasma spraying process was applied to obtain ceramic coatings on stainless steel substrates. The outer coatings were formed from pure alumina or alumina + 2 wt. % titania mixture. The nichrome intermediate coating was applied to increase adhesion of ceramic coating to stainless steel. The X-ray analysis, metallographic and SEM investigations of the sprayed coatings were also carried out. The effect of interaction of thick film conductor and resistor compositions was studied. Conductor ink P 202 PdAg and resistor ink DP 1321 were evaluated. The TCR, resistance stability were measured as a function of firing cycles. These parameters and the resistivity of sprayed alumina were compared with standard 96% alumina substrate characteristics.