Investigation of the interaction of laser radiation with composite materials by infrared spectroscopy methods

A description is given of the method and apparatus for determination of the effective temperature and composition of a jet of products of the interaction of laser radiation with a glass-fiber-reinforced plastic and an organic plastic. Measurements are also possible of the temperature and emissivity of a target when it is exposed in atmospheric air to cw CO₂ laser radiation with a flux density of 3 X 10² – 10³ W/cm². The products of damage to the glass-fiber-reinforced plastic consisted of particles of metal oxides with a diameter d₃₂ = 2.3–3.5 μm and a volume concentration C_v = (0.06–0.25)X10 ^– 4, and of molecular gases CO₂, H₂O, and HCl; the damage products of the organic plastic were conglomerates of soot particles with the diameter d₃₂ = 1–1.8 μm and a volume concentration C_v = (0.4–0.9) X 10 ^– 4, and the same molecular gases. The target emissivity increased with time and reached 0.8–0.9.