Micromechanical analysis and theoretical predictions towards thermal shock resistance of HfO2-Si environmental barrier coatings

Thermal barrier coatings (TBCs) were deposited by an Air Plasma Spraying (APS) technique. The TBC coating comprised of 92 wt.% ZrO2 and 8 wt.% Y2O3 (YSZ), CoNiCrAlY bond coat, and MarM247 nickel base super alloy. After APS of YSZ two batches of TBC specimens were tested, one batch of which was pre-oxidised in air for 10h at 1080 oC. Both types of the specimens were directly pushed into a combustion gas at 1150 oC for 25 min and then out to the natural air for quenching. The combustion gas was produced by burning jet fuel with high speed air in a high temperature wind tunnel, which simulates the real service conditions in an aeroengine. Results show that TBCs prepared by the APS had good thermal shock resistance in the combustion gas. The pre-oxidation treatment of the TBC had a significant effect on its thermal shock life. The as-oxidised TBCs always had worse thermal shock resistance than the as-sprayed ones after thermal shock cycles.

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Effect of irregular microcracks on the hot corrosion behavior and thermal shock resistance of YSZ thermal barrier coatings

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2021.128038 ◽

2021 ◽

pp. 128038

Author(s):

Kai Yan ◽

Yong Xiang ◽

Haiyuan Yu ◽

Zhenrui Li ◽

Yajing Wu ◽

...

Keyword(s):

Thermal Shock ◽

Thermal Barrier Coatings ◽

Corrosion Behavior ◽

Hot Corrosion ◽

Thermal Shock Resistance ◽

Thermal Barrier ◽

Barrier Coatings ◽

Shock Resistance

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Thermo-Physical Properties and Thermal Shock Resistance of Segmented La2Ce2O7/YSZ Thermal Barrier Coatings

Journal of Thermal Spray Technology ◽

10.1007/s11666-009-9350-1 ◽

2009 ◽

Vol 18 (4) ◽

pp. 665-671 ◽

Cited By ~ 31

Author(s):

Hongbo Guo ◽

Yi Wang ◽

Lu Wang ◽

Shengkai Gong

Keyword(s):

Physical Properties ◽

Thermal Shock ◽

Thermal Barrier Coatings ◽

Thermal Shock Resistance ◽

Thermal Barrier ◽

Barrier Coatings ◽

Shock Resistance ◽

Thermo Physical Properties

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Improving the thermal shock resistance and fracture toughness of synthesized La2Ce2O7 thermal barrier coatings through formation of La2Ce2O7/YSZ composite coating via air plasma spraying

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2020.126174 ◽

2020 ◽

Vol 399 ◽

pp. 126174

Author(s):

A.M. Fathi Dehkharghani ◽

M.R. Rahimipour ◽

M. Zakeri

Keyword(s):

Fracture Toughness ◽

Thermal Shock ◽

Composite Coating ◽

Thermal Barrier Coatings ◽

Thermal Shock Resistance ◽

Thermal Barrier ◽

Air Plasma ◽

Air Plasma Spraying ◽

Barrier Coatings ◽

Shock Resistance

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Improving Thermal Shock Resistance of Plasma-Sprayed Yttria-Stabilized Zirconia Thermal Barrier Coatings by Laser Remelting

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.472-475.2502 ◽

2012 ◽

Vol 472-475 ◽

pp. 2502-2507

Author(s):

Zong Yin Duan ◽

Dong Sheng Wang

Keyword(s):

Thermal Shock ◽

Thermal Barrier Coatings ◽

Thermal Shock Resistance ◽

Yttria Stabilized Zirconia ◽

Thermal Barrier ◽

Laser Remelting ◽

Stabilized Zirconia ◽

Barrier Coatings ◽

Shock Resistance ◽

Plasma Sprayed

This paper deals with the microstructure and thermal shock behavior of laser remelting of yttria-stabilized zirconia (YSZ) thermal barrier coatings (TBCs) deposited by plasma spraying. The microstructures of the coatings were analyzed by scanning electron microscopy (SEM). It was found that the as-sprayed ceramic coating had laminated structure with high porosity. However, the coating exhibited a dense lamellar-like layer with segment cracks on the remained plasma-sprayed porous layer. Thermal shock experiments for the two kinds of TBCs were performed by water quenching method. Testing result showed that the laser-remelted TBC had better thermal shock resistance than the as-sprayed one. The damage mode of the as-sprayed TBC was great-size whole spalling. In contract, the failure mechanism of the laser-remelted one was mainly local pelling. Segmented cracks of the top ceramic coatings caused by laser remelting improved the stress accommodation and were mainly attributed to the enhancement for thermal shock life of TBC.

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