Laser cleaning of paints and metals problems and possible solutions
Résumé
Laser cleaning of complex surfaces (paints and metals with a micrometric oxide layer) should beregarded as a complicated multi parametric physical-chemical process and a tough technicalprocedure. To ensure surface laser cleaning with a required quality, high efficiency and minimumof undesirable effects and to avoid possible thermo-chemical changes in the surface undercleaning, one should take into consideration numerous laser parameters, optical and physicalchemicalfeatures of a surface under cleaning, laser beam/surface interaction regime,environmental conditions, etc.A summarized review of the experimental results on the laser cleaning of paints on concrete,metal mirrors and stainless steel surfaces with a micrometric oxide layer performed with highrepetition rate (1-20 kHz) nanosecond lasers (5-100 ns) will be presented along with the results ofmulti parametric studies. Theoretical modeling (3D+t) for an adequate explanation of theobtained results and physical-chemical processes associated with laser cleaning will be underdiscussion. The problems of cleaning regime optimization, the appropriate choice of the laserwavelength (infrared, visible or ultraviolet) and the pulse duration (nanosecond, picosecond orfemtosecond) for complex surfaces and art objects, in particular, will be under special discussion.