The modern military industry demands the most innovative and high-quality metals and alloys, as well as
processing technologies. Iron and its alloys are a common material used for different types of weapons and military
equipment. Lasers have been widely used in the metal surface processing, but the changes that occur on laser treated metal
surfaces have not yet been sufficiently investigated. A study of morphological and chemical changes on the metal surface
induced by Nd:YAG laser treatment in ambient air is presented. A pulsed Nd:YAG laser (1064 nm, Gaussian spatial profile,
FWHM 8 ns, energy up to 525 mJ, beam diameter of 1-10 mm and fluence up to 3.5 J/cm
2
) was used. Micro-morphological
analyses of sample surfaces before and after laser treatment process were performed by optical and SEM microscopies.
EDX method was used for chemical analyses and Spectra colorimeter for investigation of induced color changes. The laser
irradiation effects were studied as a function of two laser parameters, number of laser pulses and laser fluencies, around
and over the damage threshold. The results show that there are significant differences depending on these laser parameters