PREPARATION AND CHARACTERIZATION OF LANTHANUM ZIRCONATE BY ATMOSPHERIC PLASMA SPRAY COATINGS

TBCs are one of the most advanced high temperature protective coatings and being widely used in aeronautics, motor industry and heat power station for their good performance like thermal barrier and oxidation resistance. Recently, yttria partially stabilized zirconia (8YSZ) is used as the commercial material for TBCs applications. However, the major disadvantage of YSZ is the limited operating temperature about 1200°C for the long-term application. Among the interesting candidates for TBCs, Lanthanum Zirconate (LZ) has been proposed as a promising TBCs material for its high melting point, more stable structure and lower thermal conductivity than YSZ. In the present work, LZ was synthesized by ball milling method. For typical synthesis, the mixture of La₂O₃ and ZrO₂ powders with 1:2 mole ratios were ball milled for 24 hours. The prepared, processed powders were coated by DC non-transferred Atmospheric Plasma Spray (APS) torch under different operating conditions and coating analyzed by XRD and FE-SEM.