Spate And Fibre Reinforced Composite Systems, The Pros And Contras

Since Spate became available, the thermoelastic effect has been exploited mainly to obtain the stress distribution in complex isotropic structures. Although the viability of this method has been demonstrated several times, we may point out some limitations involved with such measurements. On fibre reinforced composite systems the use of SPATE has so far been limited to simple comparative studies or to qualitative NDT-type applications. This is probably due to the lack of an adequate theory which describes the thermoelastic process for a general laminated composite structure and to the essentially different damage behaviour between isotropic and anisotropic multiphase materials. A numerical model, based on the non-adiabatic theory, will be described and experimentally validated for different composite systems. Simulations show when valid stress data are obtained using SPATE on composite systems. Circumstances in which completely corrupted stress data are obtained are also discussed.