In this research, YSZ-Alumina top coat was deposited on the Hastelloy substrate with a NiCrAlY bond coat by Atmospheric plasma spraying process. YSZ-10 wt-% Al2O3 composite coatings with pyrolysed and un-pyrolysed Al2O3 powder were deposited. High temperature oxidation and thermal shock resistance of both coatings were investigated. Thermal shock test results showed that the lifetime of the YSZ-10 wt-% Al2O3 coating was increased by the pyrolysation of the un-pyrolysed Al2O3. The network of micro-segmented cracks produced by the pyrolysation of the un-pyrolysed Al2O3 improved the strain accommodation, introducing it as the main enhancement mechanism for TBC life extension. Using of pyrolysed alumina, resulted increased in the flattening degree of the splats, and so reduction of porosity and intra-splat cracks. This, in turn, reduced the permeability of the top coat and decreased the rate of oxide growth on the bond coat.
Higuera HidalgoV, Belzunce VarelaFJ, Riba LópezJ.Cyclic high temperature oxidation of HFPD thermal sprayed CoNiCrAlY coatings under simulated gas turbine and furnace environments. Surf Eng. 2006;22(4):277–282.
GuptaM.Design of thermal barrier coatings: a modelling approach. Switzerland: Springer; 2015.
4.
VakilifardH, GhasemiR, RahimipourM.Hot corrosion behaviour of plasma-sprayed functionally graded thermal barrier coatings in the presence of Na2SO4+ V2O5 molten salt. Surf Coat Technol. 2017;326:238–246.
5.
JoshiSV, SrivastavaM.Lifetime determining factors during thermal cycling of zirconia based thermal barrier coatings. Surf Eng. 1995;11(3):233–239.
6.
HosseiniS, MirdamadiS, RastegariS.Investigating efficiency of α-Al2O3 diffusion barrier layer in oxidation of EB-PVD NiCrAlY coatings. Surf Eng. 2015;31(2):146–155.
7.
GhasemiR, ValefiZ.Electrodeposition of rhenium-base layer as a diffusion barrier between the NiCoCrAlY coating and a Ni-based superalloy. J Alloys Compd. 2018;732:470–485.
8.
WangF, GengS.High temperature oxidation and corrosion resistant Nanocrystalline coatings. Surf Eng. 2003;19(1):32–36.
KeyvaniA, SaremiM, SohiMH.Oxidation resistance of YSZ-alumina composites compared to normal YSZ TBC coatings at 1100°C. J Alloys Compd. 2011;509(33):8370–8377.
11.
SaremiM, ValefiZ, AbaeianN.Hot corrosion, high temperature oxidation and thermal shock behavior of nanoagglomerated YSZ–alumina composite coatings produced by plasma spray method. Surf Coat Technol. 2013;221:133–141.
12.
WangY, LiM, SuoH.Mechanical properties of YSZ thermal barrier coatings with segmented structure. Surf Eng. 2012;28(5):329–332.
ChenD, JordanEH, GellM.Microstructure of suspension plasma spray and Air plasma spray Al2O3-ZrO2 composite coatings. J Therm Spray Technol. 2009;18(3):421–426.
17.
XieL, ChenD, JordanEH, Formation of vertical cracks in solution-precursor plasma-sprayed thermal barrier coatings. Surf Coat Technol. 2006;201(3–4):1058–1064.
18.
ValefiZ, SaremiM.The effects of plasma spray parameters on the microstructure and phase composition of thermal barrier coatings made by SPPS process. Iran J Mater Sci Eng. 2017;14(2):11–23.
19.
SivakumarG, DusaneRO, JoshiSV.A novel approach to process phase pure α-Al2O3 coatings by solution precursor plasma spraying. J Eur Ceram Soc. 2013;33(13–14):2823–2829.
20.
Ravi ShankarA, Kamachi MudaliU.Preparation of the plasma-sprayed graded thermal barrier coating by co-injection of premixed powders through a single plasma torch. Surf Eng. 2018;34(10):728–736.
21.
RamachandranC, BalasubramanianV, AnanthapadmanabhanP.On resultant properties of atmospheric plasma sprayed yttria stabilised zirconia coating deposits: designed experimental and characterisation analysis. Surf Eng. 2011;27(3):217–229.
22.
TarasiF, MedrajM, DolatabadiA, Amorphous and crystalline phase formation during suspension plasma spraying of the alumina–zirconia composite. J Eur Ceram Soc. 2011;31(15):2903–2913.
PourbafraniM, RazaviRS, BakhshiS, Effect of microstructure and phase of nanostructured YSZ thermal barrier coatings on its thermal shock behaviour. Surf Eng. 2015;31(1):64–73.
25.
PerumalG, GeethaM, AsokamaniR, Wear studies on plasma sprayed Al2O3–40wt-% 8YSZ composite ceramic coating on Ti–6Al–4V alloy used for biomedical applications. Wear. 2014;311(1–2):101–113.
26.
GellM, JordanEH, TeicholzM, Thermal barrier coatings made by the solution precursor plasma spray process. J Therm Spray Technol. 2008;17(1):124–135.
27.
WeiS, Qun-boF, Fu-chiW, Modeling of micro-crack growth during thermal shock based on microstructural images of thermal barrier coatings. Comput Mater Sci. 2009;46(3):600–602.
28.
BrickeyM, LeeJ.Structural and Chemical Analyses of a Thermally Grown Oxide Scale in Thermal Barrier Coatings Containing a Platinum–Nickel–Aluminide Bond coat. Oxid Met. 2000;54(3–4):237–254.
TaheriM, ValefiZ, Zangeneh-MadarK.Influence of HVOF process parameters on microstructure and bond strength of NiCrAlY coatings. Surf Eng. 2012;28(4):266–272.
31.
MercerC, FaulhaberS, YaoN, Investigation of the chemical composition of the thermally grown oxide layer in thermal barrier systems with NiCoCrAlY bond coats. Surf Coat Technol. 2006;201(3–4):1495–1502.
32.
ShanmugavelayuthamG, KobayashiA.Mechanical properties and oxidation behaviour of plasma sprayed functionally graded zirconia–alumina thermal barrier coatings. Mater Chem Phys. 2007;103(2–3):283–289.
33.
BrinkieneK, KezelisR.Effect of alumina addition on the microstructure of plasma sprayed YSZ. J Eur Ceram Soc. 2005;25(12):2181–2184.
