Study of Crack Initiation and Propagation in TBCs by Experiments and Extended Finite Element Method

Abstract:

CoNiCrAlY bond coat (BC) and top ceramic coating (TCC) was fabricated on the GH99 super alloy by high velocity oxyfuel spray (HVOF) and air plasma spray (APS), respectively. Thermal cycling treatment was applied to the thermal barrier coatings (TBCs). The cross-sectional images of crack initiation and propagation of TBCs after treatment were investigated by scanning electron micrograph (SEM), meanwhile crack initiation and propagation in TBCs were analyzed based upon ABAQUS software using extended finite element method (XFEM). The results show that, crack initiation and propagation can be easily traced via microscopy at the interface areas in TBCs; after thermal cycling treatments, the crack associated with the TCC/TGO interface morphology initiates at interface peak area and propagates along TCC/TGO interface with thermal cycles; the interface roughness affects the crack magnitude in length and width obviously, the rougher the morphology, the bigger the crack is; the XFEM is a novel and effective method to well predict the crack initiation and calculate the crack propagation, and simulation and experimental results fit well.

• Periodical: Applied Mechanics and Materials (Volume 331)
• Pages: 129-132
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.331.129
• Online since: July 2013
• Authors: Jing Xin Su, Zhao Hui Ji, Zhi Yong Han, Hua Zhang
• Keywords: Crack, Propagation, TGO, Thermal Barrier Coating (TBC), XFEM

References

[1] N.P. Padture, M. Gell and E.H. Jordan, Thermal Barrier Coatings for Gas-Turbine Engine Applications[J], Science, 296, (2002), pp.280-284.

DOI: 10.1126/science.1068609

[2] Y. Liu, C. Persson and S. Melin, Numerical Modeling of Short Crack Behavior in a Thermal Barrier Coating Upon Thermal Shock Loading[J], Journal of Thermal spray Technology, 13, (2003), pp.554-560.

DOI: 10.1361/10599630421488

[3] A.M. Karlsson, T. Xu, A.G. Evans. The effect of the thermal barrier coating on the displacement instability in thermal barrier systems[J], Acta Materialia, 50 (2002), pp.1211-1218.

DOI: 10.1016/s1359-6454(01)00422-0

[4] R. Vaben, S. Giesen, and D. Stover. Lifetime of Plasma-Sprayed Thermal Barrier Coatings: Comparison of Numerical and Experimental Results[J], Journal of Thermal Spray Technology, 18(5-6), 2009, pp.835-845.

DOI: 10.1007/s11666-009-9389-z

[5] A. Asher, Y.L. Tang. Analysis of crack nets development in thermal barrier[J], 151, (2008), pp.57-79.

[6] A.M. Karlsson, T. Xu, A.G. Evans, The effect of the thermal barrier coating on the displacement instability in thermal barrier systems[J]. Acta Materialia, 50, (2002), pp.1211-1218.

DOI: 10.1016/s1359-6454(01)00422-0

[7] W.R. Chen, X. Wu, D. Dudzinski, etc. Modification of oxide layer in plasma-sprayed thermal barrier coatings[J], Surf. Coat. Technol, 200, (2006), pp.5863-5868.

DOI: 10.1016/j.surfcoat.2005.08.141

[8] M. Ranjbar-Far, J. Absi, G. Mariaux, etc. Effect of residual stresses and prediction of possible failure mechanisms on thermal barrier coating system by finite element method[J]. Journal of Thermal Spray Technology, 19(5), 2010, pp.1054-1061.

DOI: 10.1007/s11666-010-9512-1

[9] W.R. Chen, R. Archer, X. Huang, etc. TGO growth and crack propagation in a thermal barrier coating[J]. Journal of Thermal Spray Technology, 17(5-6), 2008, pp.858-864.

DOI: 10.1007/s11666-008-9251-8

[10] V. Teixeira. Residual stress and cracking in thin PVD Coatings[J]. Vacuum, 64, (2002), pp.393-399.

DOI: 10.1016/s0042-207x(01)00327-x