Crack Pattern and Damage Mode in Alumina Trilayer Structures
- Prof. T. W. Clyne and
- F. Simancik
Published Online: 21 DEC 2005
Copyright © 2000 Wiley-VCH Verlag GmbH, Weinheim
Metal Matrix Composites and Metallic Foams, Volume 5
How to Cite
Han, E.-S., Lee, C.-Y. and Choi, S.-C. (2000) Crack Pattern and Damage Mode in Alumina Trilayer Structures, in Metal Matrix Composites and Metallic Foams, Volume 5 (eds T. W. Clyne and F. Simancik), Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, FRG. doi: 10.1002/3527606203.ch32
Department of Materials Science and Metallurgy, Cambridge University, Pembroke Street, Cambridge CB2 3QZ, U.K.
- Published Online: 21 DEC 2005
- Published Print: 20 APR 2000
Print ISBN: 9783527301263
Online ISBN: 9783527606207
- alumina trilayer structures;
- crack pattern;
- damage mode
In this work, symmetric alumina trilayer structures, which composed of coarse and fine microstructure, were studied for the optimized design of damage tolerant materials. A major feature of the layer structures is an improved damage resistance due to either crack deflection or arrest in the adjacent heterogeneous interface. The purpose of this study is to reveal the influence of microstructure on crack propagation and damage mode in Hertzian indentation test. Hertzian and Vickers indentation tests were used to introduce controlled cracks in the fine or coarse top layers close to the interface. Effect of microstructure on the contact damage and the crack propagation in the trilayer structures were investigated by optical microscope and scanning electron microscope. And contact damage and deformation on subsurface as well as on surface were observed.
As results, the fine and coarse microstructures represent a different indentation response and damage mode: fine microstructure shows brittle behavior and classical cone cracking; coarse microstructure shows quasi-plastic behavior and deformation derived from microfailure by shear faulting at the week boundaries region of high shear stress concentrations. Therefore, in the layer structures formed with the fine and coarse microstructures, various forms of crack pattern and damage mode can be observed dependant on microstructure and interface design. And these effects will give some damage tolerant to Materials.