Properties of plasma sprayed NiCrAlY+（ZrO₂+Y₂O₃） coating on refractory steel surface

NiCrAlY+(ZrO_2+Y_2O_3)thermal barrier coating was prepared on the surface of refractory steel 1Cr18Ni9Ti with plasma spraying technique. The phases and microstructure of the thermal barrier coating were determined by scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results show that the bonding between thermal barrier coating and substrate is sound. The surface hardness of 1Cr18Ni9Ti reaches up to 1000 HV, but that of substrate is only 300HV. The patterns sprayed with CoNiCrAlY+(ZrO_2+Y_2O_3) ceramic coating have a good heat insulation effect at 800℃ for heat insulation temperature difference reaches 54℃, which increases the operating temperature and service life of refractory steel.