The analysis of damage threshold in the ruby laser interaction with copper and aluminium

Nondestructive methods are dominant in diagnosing the status and protection of all kinds of contemporary industrial object, as well as object of industrial heritage. Laser methods open wide possibilities of research in the field of diagnosis and metal processing. This paper presents the results of laser radiation interaction (wavelength ? = 694.3 nm, Ruby laser, Q-switch mode) with metal samples covered with a deposit. The goal of the examination was to determine the maximum energy density, that can be used in diagnostics purpouses (interferometric methods, 3D scanning, i.e.) and as a tool for safe removal of deposits, without interacting with the basic material. Microscopic examination performed with SEM coupled with EDX allowed the determination of the safe laser light energy density levels, which caused the removal of the deposite from the surface of the sample, without degradation of the surface. The energy density up to 20 103 J/m2 is maximum allowed for the diagnosis or deposit removal. nema