Thermomechanical behaviour of composites under local intense heating by irradiation

Thermomechanical behaviour of a polymer-matrix composite plate under local heating by irradiation is investigated. Using a thermomechanical model of the high-temperature behaviour of composites developed previously and with the help of numerical methods, peculiarities of thermal stresses, internal heat and mass transfer and charring induced by intense local heating have been studied. It was established that, unlike one-dimensional heating, for this case additional thermal stresses in composites appear: interlayer shear and shrinkage tangential stresses, which together with tensile through-thickness stresses are causes of delamination and cracking in a composite under local heating. Pore gas pressure, appearing at matrix thermodecomposition, is shown to play an important role at local heating. (C) 2000 Elsevier Science Ltd. All rights reserved.