Improving the hot corrosion resistance of plasma sprayed ceria–yttria stabilized zirconia thermal barrier coatings by laser surface treatment

• Surface of plasma sprayed CYSZ TBCs modified by a pulsed Nd:YAG laser.
• A dense glazed layer produced on the surface of TBCs by laser treatment.
• The specific reaction area was reduced after laser glazing.
• The hot corrosion resistance of TBCs was enhanced more than twofold by laser surface glazing.

Ceria–yttria stabilized zirconia (CYSZ) thermal barrier coatings (TBCs) were deposited by air plasma spraying on NiCoCrAlY-coated Inconel 738LC substrates. After that, the surface of plasma sprayed CYSZ TBCs were glazed using a pulsed Nd:YAG laser. The effects of laser glazing on hot corrosion resistance of the coatings were evaluated in presence of 45 wt%Na2SO4 + 55 wt%V2O5 corrosive molten salt at 1000 °C. The results revealed that the hot corrosion resistance of plasma sprayed CYSZ TBCs were enhanced more than twofold by laser surface glazing due to reducing specific reactive area of the dense glazed surface layer and consequently, decreasing the reaction between molten salt and zirconia stabilizers.

Figure optionsDownload as PowerPoint slide