TY - JOUR KW - USA KW - Emission KW - Pulse KW - Power KW - Behavior KW - Ablation KW - Laser KW - Laser ablation KW - Laser ablation KW - Spectroscopy KW - Vaporization KW - Time KW - Beam KW - Ca KW - E KW - Inductively coupled plasma (icp) KW - Inductively-coupled plasma KW - Mass KW - Mass spectrometry KW - Plasma KW - Ablated mass KW - Atomic emission KW - Atomic emission spectroscopy KW - Brass KW - Emission spectroscopy KW - Emission spectroscopy KW - Lasers KW - Process KW - Properties KW - Property KW - Ratio KW - Zn KW - Elemental analysis KW - Excimer KW - Excimer laser KW - Mechanism KW - Mechanisms KW - Nd:yag KW - Stoichiometry KW - Picosecond laser KW - Density KW - Thermal KW - Thermal vaporization KW - Ablation process KW - Duration KW - Laser ablation process KW - Nd:yag laser KW - Pulse duration KW - Solid samples KW - Laser beam KW - Laser power density KW - Nanosecond laser KW - Wavelength KW - Excimer laser KW - Pulse width KW - Region KW - Preferential vaporization KW - Rich KW - U.S. AU - Xianglei Mao AU - Adeline C Ciocan AU - Richard E Russo AB -

The Zn-to-Cu ratio in brass was measured by laser ablation inductively coupled plasma atomic emission spectroscopy. The influence of laser beam properties (pulse width, wavelength, and power density) on fractional laser ablation was investigated. The behavior of the Zn/Cu ratio vs, laser power density shows that there are different mechanisms influencing ps and us laser ablation. With the use of a 30 ns pulse duration from an excimer laser, thermal vaporization appears to be the dominant process in the low-power density region. The Zn/Cu ratio approaches stoichiometry at higher power density, but the ablated mass still remains Zn rich. With a 35 ps pulse Nd:YAG laser, a nonthermal mechanism appears to govern the laser ablation process. When a 3 ns Nd:YAG laser is used, both thermal and nonthermal processes exist. For both 3 us and 30 ps Nd:YAG lasers, stoichiometric ablation can be achieved at higher power densities

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Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA

AN - 101 BT - Applied Spectroscopy C2 - LBNL-41833 LA - eng LB - Laser N1 -

LBNL-41833 NOT IN FILE

N2 -

The Zn-to-Cu ratio in brass was measured by laser ablation inductively coupled plasma atomic emission spectroscopy. The influence of laser beam properties (pulse width, wavelength, and power density) on fractional laser ablation was investigated. The behavior of the Zn/Cu ratio vs, laser power density shows that there are different mechanisms influencing ps and us laser ablation. With the use of a 30 ns pulse duration from an excimer laser, thermal vaporization appears to be the dominant process in the low-power density region. The Zn/Cu ratio approaches stoichiometry at higher power density, but the ablated mass still remains Zn rich. With a 35 ps pulse Nd:YAG laser, a nonthermal mechanism appears to govern the laser ablation process. When a 3 ns Nd:YAG laser is used, both thermal and nonthermal processes exist. For both 3 us and 30 ps Nd:YAG lasers, stoichiometric ablation can be achieved at higher power densities

PY - 1998 SP - 913 EP - 918 T2 - Applied Spectroscopy TI - Preferential vaporization during laser ablation inductively coupled plasma atomic emission spectroscopy VL - 52 ER -