Research on Crack Failure Modes of Thermal Barrier Coatings Based on Acoustic Emission Technique

doi:10.3901/JME.2020.14.057

Abstract

Abstract: Thermal barrier coatings (TBCs) is a typical brittle, heterogeneous, multilayer structure material. The heat-loading effect during service will lead to premature peeling failure of the coating. The main failure modes are ceramic coating cracking and interface spalling failure. The failure of TBCs is mainly the accumulation of micro-cracks, the expansion and the accumulation of connectivity results. The failure process of TBCs under tensile load is studied by using acoustic emission (AE) technique combined with microscopic morphology observation, and the crack damage mode of TBCs is identified. According to the microscopic morphology observation under different loads, the failure process of the TBCs under tensile load is studied. The TBCs is applied by the AE characteristic parameter analysis method (such as AE events, AE amplitude). The failure process is divided into several stages, and the relationship between AE characteristic parameters and crack damage failure information is established based on the observation of morphology. The TBCs failure modes is identified by fast Fourier transform (FFT). The results show that the tensile failure process of the TBCs is that the crack firstly sprouts on the surface of the ceramic coating and then spreads to the interface of the ceramic coating/bond coating. After reaching the interface, the crack will grow and propagate along the interface, eventually leading to ceramic coating is peeled off. The failure process of the TBCs is divided into four steps; the spectrum analysis shows that the frequency component of the substrate is around 0.020 MHz, the frequency component of the surface crack is 0.20-0.25 MHz, and the interface crack is 0.15-0.20 MHz.

Key words: thermal barrier coatings, acoustic emission technique, fast Fourier transform, crack propagation, failure mode

CLC Number:

TG115

LI Xuehuan, DI Yuelan, WANG Haidou, LI Guolu, DONG Lihong. Research on Crack Failure Modes of Thermal Barrier Coatings Based on Acoustic Emission Technique[J]. Journal of Mechanical Engineering, 2020, 56(14): 57-64.

References

[1] PADTURE N P, GELL M, JORDAN E H. Thermal barrier coatings for gas-turbine engine applications[J]. Science, 2002, 296(5566):280-284.
[2] MARINO K A, HINNEMANN B, CARTER E A. Atomic-scale insight and design principles for turbine engine thermal barrier coatings from theory[J]. Proceedings of the National Academy of Sciences of the United States of America, 2011, 108(14):5480-5487.
[3] BÄKER M, SEILER P. A guide to finite element simulations of thermal barrier coatings[J]. Journal of Thermal Spray Technology, 2017, 26(6):1146-1160.
[4] CLARKE D R, LEVI C G. Materials design for the next generation thermal barrier coatings[J]. Annual Review of Materials Science, 2003, 33(33):383-417.
[5] AKTAA J, SFAR K, MUNZ D. Assessment of TBC systems failure mechanisms using a fracture mechanics approach[J]. Acta Materialia, 2005, 53(16):4399-4413.
[6] CHEN Z B, WANG Z G, ZHU S J. Tensile fracture behavior of thermal barrier coatings on superalloy[J]. Surface & Coatings Technology, 2011, 205(15):3931-3938.
[7] 周益春, 刘奇星, 杨丽, 等. 热障涂层的破坏机理与寿命预测[J]. 固体力学学报, 2010, 31(5):504-531. ZHOU Yichun, LIU Qixing, YANG Li, et al. Failure mechanism and life prediction of thermal barrier coatings[J]. Acta Mechanica Solida Sinica, 2010, 31(5):504-531.
[8] 王铁军, 范学领, 孙永乐, 等. 重型燃气轮机高温透平叶片热障涂层系统中的应力和裂纹问题研究进展[J]. 固体力学学报, 2016, 37(6):477-517. WANG Tiejun, FAN Xueling, SUN Yongle, et al. Research progress on stress and crack in high temperature turbine blade thermal barrier coating system for heavy gas turbines[J]. Acta Mechanica Solida Sinica, 2016, 37(6):477-517.
[9] 李雪换, 底月兰, 王海斗, 等. 基于声发射技术的热障涂层损伤行为[J]. 材料导报, 2018, 32(19):91-97. LI Xuehuan, DI Yuelan, WANG Haidou, et al. Failure behavior of thermal barrier coatings based on acoustic emission technique[J]. Materials Reports, 2018, 32(19):91-97.
[10] YANG L, ZHONG Z C, YOU J, et al. Acoustic emission evaluation of fracture characteristics in thermal barrier coatings under bending[J]. Surface & Coatings Tech-nology, 2013, 232(10):710-718.
[11] YANG L, ZHOU Y C, LU C. Damage evolution and rupture time prediction in thermal barrier coatings subjected to cyclic heating and cooling:An acoustic emission method[J]. Acta Materialia, 2011, 59(17):6519-6529.
[12] WANG L, NI J X, SHAO F, et al. Failure behavior of plasma-sprayed yttria-stabilized zirconia thermal barrier coatings under three-point bending test via acoustic emission technique[J]. Journal of Thermal Spray Technology, 2017, 26(1-2):116-131.
[13] 刘国华. 声发射信号处理关键技术研究[D]. 杭州:浙江大学, 2008. LIU Guohua. The research on the key technologies in acoustic emission signal processing[D]. Hangzhou:Zhejiang University, 2008.
[14] SEONG S H, HUR S, KIM J S, et al. Development of diagnosis algorithm for the check valve with spectral estimations and neural network models using acoustic signals[J]. Annals of Nuclear Energy, 2005, 32(5):479-492.
[15] PATAPY C, PROUST A, MARLOT D, et al. Characterization by acoustic emission pattern recognition of microstructure evolution in a fused-cast refractory during high temperature cycling[J]. Journal of the European Ceramic Society, 2010, 30(15):3093-3101.
[16] PEARSON T C, CETIN A E, TEWFIK A H, et al. Feasibility of impact-acoustic emissions for detection of damaged wheat kernels[J]. Digital Signal Processing, 2007, 17(3):617-633.
[17] CHUNG K H, OH J K, MOON J T, et al. Particle monitoring method using acoustic emission signal for analysis of slider/disk/particle interaction[J]. Tribology International, 2004, 37(10):849-857.
[18] YU Y H, CHOI J H, KWEON J H, et al. A study on the failure detection of composite materials using an acoustic emission[J]. Composite Structures, 2006, 75(1):163-169.
[19] LEE J B, JUNG J P, LEE M H, et al. Effects of bottom electrodes on the orientation of AlN films and the frequency responses of resonators in AlN-based FBARs[J]. Thin Solid Films, 2004, 447:610-614.
[20] 钟志春. 热障涂层表面开裂与界面剥离失效的声发射定量评价[D]. 湘潭:湘潭大学, 2013. ZHONG Zhichun. Quantitative failure assessment for surface cracking and interface delamination of thermal barrier coatings by acoustic emission[D]. Xiangtan:Xiangtan University, 2013.
[21] 杨丽. 热障涂层氧化、损伤与断裂的无损评价研究[D]. 湘潭:湘潭大学, 2007. YANG Li. Nondestructive evaluation of oxidation, damage and fracture of thermal barrier coatings[D]. Xiangtan:Xiangtan University, 2007.
[22] YAO W B, DAI C Y, MAO W G, et al. Acoustic emission analysis on tensile failure of air plasma-sprayed thermal barrier coatings[J]. Surface & Coatings Technology, 2012, 206(18):3803-3807.
[23] YANG L, ZHOU Y C, MAO W G, et al. Real-time acoustic emission testing based on wavelet transform for the failure process of thermal barrier coatings[J]. Applied Physics Letters, 2008, 93(23):299.
[24] YANG L, ZHONG Z C, ZHOU Y C, et al. Acoustic emission assessment of interface cracking in thermal barrier coatings[J]. Acta Mechanica Sinica, 2016, 32(2):342-348.
[25] ZHU W, YANG L, GUO J W, et al. Determination of interfacial adhesion energies of thermal barrier coatings by compression test combined with a cohesive zone finite element model[J]. International Journal of Plasticity, 2015, 64(7):76.