Izvorni znanstveni članak
CO2 and Nd:YAG laser radiation induced damage in aluminium
Shazia Bashir
; Centre for Advanced Studies in Physics, Government College University Lahore, Pakistan
M. S. Rafique
; Advanced Physics Laboratory, University of Engineering and Technology Lahore, Pakistan
M. Khaleeq-ur-Rahman
; Advanced Physics Laboratory, University of Engineering and Technology Lahore, Pakistan
Faizan-ul- Haq
; Centre for Advanced Studies in Physics, Government College University Lahore, Pakistan
B. R. Alvina
; Centre for Advanced Studies in Physics, Government College University Lahore, Pakistan
Sažetak
The change in the electrical properties of pure aluminium (Al 99.999%) after exposure to CO2 (energy = 2.5 J/pulse, wavelength = 10.6 µm, pulse duration = 200 nsec) and Nd:YAG (energy = 10 mJ/pulse, wavelength = 1.06 µm and pulse duration = 12 nsec) laser radiation is investigated. The samples were exposed to laser radiations for different numbers of pulses. The change in electrical characteristics of Al is studied under different ambient conditions, after irradiating the samples in air, vacuum and hydrogen at different pressures. After exposure, the electrical conductivity of Al is measured by the four probe method. The electrical conductivity decreases with increasing number of pulses. The damage in air and in hydrogen is more pronounced than in vacuum which can be attributed to collisionnal sputtering of Al by plasma ions of air molecules and hydrogen, respectively. The change in the conductivity in hydrogen is pressure-dependent. Some theoretical considerations are also made, e.g. the phonon speed in Al during the photon interaction, minimal melting and evaporation energy per volume, damage threshold energy, penetration depth, the mass of heated volume and average temperature rise at the Al surface during laser irradiation.
Ključne riječi
TEA CO2 laser radiation; Nd:YAG laser radiation; damage; electrical conductivity; collisionnal sputtering
Hrčak ID:
302076
URI
Datum izdavanja:
2.7.2006.
Posjeta: 203 *