A STUDY OF LASER COMPOSITE-MATERIAL INTERACTIONS

The effects of laser irradiation on strength reduction and on the dynamic and buckling characteristics of organic-matrix composite laminates have been investigated. An integral methodology used in this paper considered the evaluation of the heat transfer process, non-linear composite plate response, failure modes, and eigenvalues for natural frequency and buckling load. The heat transfer process was modelled by a modified Crank-Nicholson finite difference scheme, which includes the effects of surface ablation, degradation of thermophysical properties at elevated temperatures, and radiation and convection heat losses. The predicted burnout geometry configuration and temperature distribution were then used for the subsequent investigations of load-carrying capability, free vibration, and buckling of the laminates. It was shown that material removal due to ablation and mechanical property degradation at elevated temperatures could significantly reduce load-carrying capability and alter vibration and buckling characteristics of the laminated composites.