Hot corrosion characteristics of SrCeO3 as thermal barrier coating material

This study investigates the thermal barrier and hot corrosion characteristics of SrCeO 3 , a perovskite-structured material, synthesized via the solid-state method using SrCO 3 and CeO 2 as precursors. The crystal structure was confirmed by x-ray diffraction (XRD), and the elemental composition matched theoretical values based on energy-dispersive spectroscopy (EDS). Thermal analysis showed that SrCeO 3 is phase stable up to 1400ºC, with thermal conductivity lower than that of yttria-stabilized zirconia (YSZ), though the coefficient of thermal expansion was similar. Mechanical properties, including elasticity, hardness, and fracture toughness, were found to be inferior to those of YSZ. Additionally, SrCeO 3 showed incompatibility with thermally grown oxide (TGO) layers, reacting with Al 2 O 3 at high temperatures. Atmospheric plasma sprayed coatings of SrCeO 3 showed minimal decomposition, with only trace amounts of Sr(OH) 2 and CeO 2 formed during spraying. The high-temperature corrosion behavior of SrCeO 3 was examined in a 32 wt% Na 2 SO 4 + 68 wt% V 2 O 5 salt mixture and pure V 2 O 5 at 900ºC for 30 h. In the salt mixture, Sr 3 V 2 O 8 was the primary corrosion product, whereas SrV 2 O 6 formed in pure V 2 O 5 . The Na 2 SO 4 in the salt mixture increased the corrosive activity by enhancing V 2 O₅ reactivity. Importantly, no Ce-V-O corrosion product was observed, confirming that corrosion followed the Lewis acid-base principle.