High performance composite structures produced by the processes at which the consolidation of the fibres and matrix is done at the same time as the component is shaped. Full curing schedule include a pre-warming for resin liquefaction, next apply of pressure to remove the gas bubbles, and finally consolidation of resin at elevated temperature to its full polymerization. The change in the state of the composite should be made as possible uniformly across the thick-walled products. The complexity of process control is due to unobservability of the rheological state of material in a closed volume of a mould. In this paper we propose a mathematical model of epoxy-based thick-walled composite structure curing. PDE system linking a kinetic equation of the resin cure with heat transfer equation, take into account a phase transition from liquid to gel and further to the solid state. On the basis of transient analysis of the developed model we optimize the temperature control law.

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The requirements for quality parameters in radiation of different wavelength (i.e. CO 2 lasers and fiber lasers) have been defined so as to perform efficient oxygen-free gas laser cutting of large-thickness samples.The main channels of consumption of radiation power in the cutting process have been considered. It is noted that focused beam divergence not only decreases the cutting speed, but also causes cutting quality deterioration.