Lowering the sintering temperature for EPD coatings by applying reaction bonding

Abstract Electrophoretic deposition (EPD) allows the fabrication of ceramic coatings, for example of thermal barrier coatings for turbine engines, at lower cost and higher speed than most other deposition techniques. The commonly used sintering temperatures of more than 1200 °C however may damage the metal parts and also lead to high production costs. This study suggests a powder mixture of zirconia and zirconium nitride to lower the sintering temperature, where during sintering in air at 1000 °C a homogenous, porous zirconia coating was obtained. The thermal conductivity determined by laser flash experiments proved to be significantly lower than that of conventional thermal barrier coatings.