The fractionation behavior induced by laser desorption and ablation of the Al70Cu20Fe10 intermetallic alloy and of the Al65Cu23Fe12 quasicrystal has been examined in terms of the structural properties of the two compounds. Elemental fractionation during laser desorption and ablation sampling was investigated by using inductively coupled plasma mass spectrometry. The experiments were carried out in two different power density regimes by using a Nd-YAG laser with 266 nm wavelength and single 6 ns laser pulses. In the high power density regime (>0.04–0.07 GW/cm2) the effect of the laser power density on ablation behavior was similar for the two materials. In the low power density regime (<0.04–0.07 GW/cm2) large differences have been found between the alloy and the quasicrystal. The results are interpreted on the basis of a thermodynamic vaporization process for the intermetallic alloy. An electronic model of localized excitation is suggested for the physical process of surface material removal from a quasicrystal.
AD -Univ Roma La Sapienza, Dipartimento Chim, I-00185 Rome, Italy Lawrence Berkeley Lab, Berkeley, CA 94720 USA CNR, Inst Mat Speciali, I-85050 Tito, PZ, Italy Chinese Acad Sci, Guangzhou Inst Geochem, Guangzhou 510640, Peoples R China
BT - Applied Surface Science C2 - LBNL-51126 DA - 01/2002 DO - 10.1016/S0169-4332(01)00664-X IS - 1-4 LA - eng LB - Laser N2 -The fractionation behavior induced by laser desorption and ablation of the Al70Cu20Fe10 intermetallic alloy and of the Al65Cu23Fe12 quasicrystal has been examined in terms of the structural properties of the two compounds. Elemental fractionation during laser desorption and ablation sampling was investigated by using inductively coupled plasma mass spectrometry. The experiments were carried out in two different power density regimes by using a Nd-YAG laser with 266 nm wavelength and single 6 ns laser pulses. In the high power density regime (>0.04–0.07 GW/cm2) the effect of the laser power density on ablation behavior was similar for the two materials. In the low power density regime (<0.04–0.07 GW/cm2) large differences have been found between the alloy and the quasicrystal. The results are interpreted on the basis of a thermodynamic vaporization process for the intermetallic alloy. An electronic model of localized excitation is suggested for the physical process of surface material removal from a quasicrystal.
PY - 2002 SP - 322 EP - 328 T2 - Applied Surface Science TI - Inductively coupled plasma mass spectrometric study of laser sputtering from the surface of an Al-Cu-Fe alloy and quasicrystal VL - 186 ER -