2O 3-ZrO 2 Thermal Barrier Coatings]]>

摘要

AbstractIn this study, three groups of thermal barrier coatings (TBCs) samples were remelted by CO2laser with different laser energy densities (1, 5 and 10?J/mm2) to seal the surface of yttria-stabilized zirconia (YSZ) coatings. Microscopic observations showed that the cracks size and the remelted depth in YSZ coatings increased. A ~?50-μm-thick dense layer was formed on the surface of YSZ coating in samples with 1?J/mm2energy density. Microindentation tests showed that the Vickers hardness of YSZ coatings increases with the increase in laser energy density. After isothermal oxidation at 1200?°C for 200 h, thinner thermally growth oxides were found in laser remelted YSZ samples under energy density of 1?J/mm2(6.32?±?0.28?μm). Cyclic oxidation results showed that the weight gain per unit area of low energy density laser remelted TBCs was smaller than that of the high energy density laser remelted and as-sprayed TBCs.]]>