Mechanical Properties and CMAS Corrosion Resistance of La_2Ce_2O_7/YSZ Composite Thermal Barrier Coatings

摘要

50 vol. % La_2Ce_2O_7 (LC)/yttria partially stabilized zirconia (YSZ) composite thermal barrier coating (TBC) was deposited by supersonic atmospheric plasma spraying (SAPS). The mixture of LC and YSZ can effectively eliminate the sudden decrease of thermal expansions coefficients of LC. The results of CMAS corrosion tests indicated that the LC/YSZ composite coating reveals high resistance to the penetration of CMAS with reprecipitation of La-Ce apatite, CaAl_2Si_2O_8. MgAl_2O_4 and t-ZrO_2. Furthermore, compared to YSZ coating, the LC/YSZ composite coating can obviously improve the thermal cycling lives under CMAS corrosion.