Properties of plasma sprayed ytrria stabilized zirconia thermal barrier coating prepared from co-precipitation synthesized powder

摘要

In the present work, plasma sprayable 8 wt% YSZ powder has been prepared by the co-precipitation method without using any agglomeration process. The suitability of the synthesized YSZ powder for TBC application has been explored by evaluating the properties of the plasma sprayed coating. The powders were characterized for phase, particle size, morphology and flowability. The plasma sprayed coatings were characterized for microstructure, porosity, hardness, Young's modulus, thermal conductivity and thermal cyclic behavior. Plasma sprayed YSZ coating obtained from the coprecipitation synthesized powders with 15% porosity exhibited a thermal conductivity of 0.75 W/mK at 900 °C. The coating also exhibited good spallation resistance as evident from thermal cycling studies and no phase change was observed during thermal cycling. The thermally grown oxide layer formed during thermal cycles was < 5 μm in the coatings subjected to thermal cycles.