METHOD AND DEVICE FOR TREATING THERMOPLASTIC AND/OR SUBLIMING MATERIAL ARTICLES Russian patent published in 1994 - IPC

FIELD: laser treatment of thermoplastic materials. SUBSTANCE: method involves setting the level of submersion of article into process fluid within the range of h_max≥ d_min=W/Kρ·S·q, where d is thickness of process fluid body above article surface, h_max is maximum depth of penetration of vapor-gas channel into fluid, h_min is minimum depth of penetration of vapor-gas channel into fluid, W is laser radiation power, K is constant classifying process fluid in accordance with interaction between this fluid and laser radiation, ρ is density of this fluid, S is inlet section area of vapor-gas channel, q is specific heat of evaporation of process fluid. Temperature of process fluid is maintained equal to 95-98% of one of minimum values of boiling temperature of this fluid or article material fusion temperature. Laser radiation power density on fluid surface is chosen to be not less than K·ρ·q·d and inclination angle α of laser beam axis is chosen to be within the range of 5-80 deg. Displacement of laser beam relative to article is effectuated in the direction of angle of inclination according to the rate of disintegration of article material. Infrared laser radiation is used for treatment. A layer of predetermined thickness is formed over article area of treatment by supplying a flow of process fluid. Solutions reacted with gaseous products of article material disintegration and water may be used as process fluid. Device is provided with third nozzle for supplying washing and cooling liquid or with second nozzle mounted outside. Generatrices of all the nozzles are extending in such a way that they have common intersection point. EFFECT: high quality of treatment. 6 cl, 1 tbl, 3 dwg