Thermal barrier coatings with interface modified by 3D mesh patterns: Failure analysis and design optimization. Issue 5 (26th December 2017)

• Record Type: Journal Article
• Authors: Luo, Lirong; Shan, Xiao; Guo, Yi; Zhao, Chunshan; Wang, Xin; Zhao, Xiaofeng; Guo, Fangwei; Xiao, Ping
• Is Part Of: Journal of the American Ceramic Society. Volume 101:Issue 5(2018)
• Page Start: 2084
• Page End: 2095
• Publication Date: 2017-12-26
• Subjects: failure -- interfaces -- stress -- thermal barrier coatings (TBC); Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.15386
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract: Surface patterning of the bond coat using a three‐dimensional mesh offers a promising approach to improve the durability of the thermal barrier coatings (TBCs), in which the geometry parameters of the mesh play a vital role. The objective of this work is to investigate the failure behavior of the air‐plasma sprayed TBCs with mesh, and to identify the optimal mesh design. The study revealed that the failure sequence of the TBCs with mesh patterns consisted of (I) initiation of the interfacial and ridge cracks (around the top of the mesh); (II) cracks propagation and buckling of the YSZ layer; (III) interfacial cracks deflection and coalescence with ridge cracks, leading to final spallation. The critical parameters governing each step of the failure sequence were discussed and proposed. For a typical TBCs with YSZ thickness about 200 μm, the critical mesh height h and spacing length L is about 110 μm and 7 mm, respectively, when the mesh width w is fixed at about 480 μm.