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Surface of a Cu-Sn-Zn-Pb alloy was irradiated by ultraviolet nitrogen laser pulses (wavelength 337 nm). As a result both surface topography and microstructure beneath the surface changed. Since it is very difficult to adequately prepare the damaged regions for microscopical observations using classical metallographic methods, we used a focussed ion beam (FIB) as the main tool for microstructural characterisation. Namely, FIB can remove material at specific sites in micro- and nanoregions and reveal microstructure without any previous metallographic preparation. This allowed us to investigate the influence of laser pulses on change of surface topography and subsurface microstructure. Površino zlitine Cu-Sn-Zn-Pb smo obsevali z laserskimi impulzi dušikovega laserja (valovna dolžina 337 nm). Pri tem sta se spremenila tako topografija površine kot tudi mikrostruktura pod njo. Ker je s klasičnimi metalografskimi metodami zelo težko primerno pripraviti obsevano površino za mikroskopsko opazovanje, smo kot temeljno orodje za metalografsko preiskavo uporabili fokusirani ionski curek (FIB), kajti FIB lahko odstranjuje material na specifičnih mestih v mikro- in nanoobmočju in odkrije mikrostrukturo brez prejšnje metalografske priprave. To nam je omogočilo, da smo raziskali vpliv obsevanja z laserjem na spremembo oblike površine, ugotovili profil kraterjev ter mikrostrukturne spremembe v območju toplotnega vpliva. |
