Published 4 issues per year
ISSN Print: 1093-3611
ISSN Online: 1940-4360
Indexed in
FORMATION OF MICROSTRUCTURES AND OXIDES ON STRUCTURAL STEEL BY NANOSECOND LASER IRRADIATION
ABSTRACT
Results of laser-induced oxidation (100−500 Hz frequency, 1064 nm wavelength, and 1 ns pulse duration) and formation of micro- and nanostructures on the surface of high-quality structural carbon steel (0.42 wt.% C, 0.5 wt.% Mn, 0.25 wt.% Cr) are presented. The steel samples were irradiated in ambient air, water, 3% hydrogen peroxide, and ethanol by a series of laser pulses at a power density of (3.2−4.4)·109 W/cm2, which is close to the ablation threshold. The surface structures were examined by optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Raman spectroscopy. Different kinds of structures detected on the steel surface and the efficiency of oxide formation depend strongly on both the liquid or gaseous environments and the parameters of laser treatment. It was found that the efficiency of nano/microstructures and oxides formation on structural steel is especially expressed for samples irradiated in air and hydrogen peroxide environments.