Troisiéme Conférence Européenne sur les Matériaux et les Procédés Avancés
J. Phys. IV France 03 (1993) C7-1875-C7-1881
The modelling and control of failure in bi-material ceramic laminatesA.J. PHILLIPPS, S.J. HOWARD, W.J. CLEGG and T.W. CLYNE
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ, England
Recent experimental and theoretical work on simple, single phase, laminated systems has indicated that failure resistant ceramics can be produced using an elegant method that avoids many of the problems and limitations of comparable fibrous ceramic composites. Theoretical work on these laminated systems has shown good agreement with experiment and simulated the effects of material properties and laminate structure on the composite performance. This work has provided guidelines for optimised laminate performance. In the current study, theoretical work has been simply extended to predict the behaviour of bi-material laminates with alternating layers of weak and strong material with different stiffnesses. Expressions for the strain energy release rates of internal advancing cracks are derived and combined with existing criteria to predict the failure behaviour of these laminates during bending. The modelling indicates three modes of failure dictated by the relative proportions, thicknesses and interfacial properties of the weak and strong phases. A critical percentage of strong phase is necessary to improve failure behaviour, in an identical argument to that for fibre composites. Incorporation of compliant layers is also investigated and implications for laminate design discussed.
© EDP Sciences 1993