Fracture of thermal barrier coating with multiple surface cracks and delaminations: Interlayer effect
来源期刊：中南大学学报(英文版)2014年第7期
论文作者：FAN Xue-ling(范学领) XU Rong(许荣) M. Kikuchi
文章页码：2579 - 2583
Key words：thermal barrier coating; delamination; interlayer; energy release rate
Abstract: Multiple surface cracks and interfacial delamination are the major failure mechanisms in film/substrate systems. The effect of interlayer upon the failure mechanisms of interfacial delamination concomitant to surface crack was explored. Finite element model was developed to obtain the stress and energy release rate (ERR), which governs the propagation of interface cracks. The dependences of delamination upon the geometry and constitutive properties of interlayer were examined. The results indicate that the effect of elastic modulus of interlayer on the steady state ERR is insignificant. In cases of different geometrical parameters, however, the steady ERR decreases with the increase of the interlayer thickness. These findings lead to the conclusion that the interlayer constraint has significant effect on the ERR and thus coating life, which can be adopted to modify the ceramic top coat.
FAN Xue-ling(范学领)1, XU Rong(许荣)1, M. Kikuchi2
(1. State Key Laboratory for Strength and Vibration of Mechanical Structures
(School of Aerospace Engineering, Xi’an Jiaotong University), Xi’an 710049, China;
2. Department of Mechanical Engineering, Faculty of Science and Technology,
Tokyo University of Science, Chiba 278-8510, Japan)
Abstract:Multiple surface cracks and interfacial delamination are the major failure mechanisms in film/substrate systems. The effect of interlayer upon the failure mechanisms of interfacial delamination concomitant to surface crack was explored. Finite element model was developed to obtain the stress and energy release rate (ERR), which governs the propagation of interface cracks. The dependences of delamination upon the geometry and constitutive properties of interlayer were examined. The results indicate that the effect of elastic modulus of interlayer on the steady state ERR is insignificant. In cases of different geometrical parameters, however, the steady ERR decreases with the increase of the interlayer thickness. These findings lead to the conclusion that the interlayer constraint has significant effect on the ERR and thus coating life, which can be adopted to modify the ceramic top coat.
Key words:thermal barrier coating; delamination; interlayer; energy release rate
