Slurry and Plasma‐spray Coating of Selective Emitting Rare‐earth Oxides on High Temperature Resistant Substrates

Selective emitting coatings of the rare‐earth oxides Yb2O3 and Yb‐doped garnet have been applied on SiC by slurry coating and on the high refractory intermetallic compound MoSi2 by vacuum plasma‐spraying. The TPV emitters produced are fully operable in oxygen atmosphere at high temperatures > 1500 °C. The novel technique of pairing MoSi2 substrate with plasma‐sprayed rare‐earth oxide results in highly thermal shock stable emitters due to an ideal match of the thermal expansion coefficients of intermetallic compound and ceramics.