Materials Removals During Femtosecond Laser Non-Thermal Ablation of Dielectrics
It remains a big challenge to theoretically predict the material removals mechanism in femtosecond laser ablation. To bypass this unresolved problem, many calculations of femtosecond laser ablation of non-metals have been based on free electron density distribution without the actual consideration of the phase change mechanism. However, this widely-used key assumption needs further theoretical and experimental confirmations. By combining the plasma model and improved two-temperature model developed by the authors, this study focuses on investigating ablation threshold fluence, depth, and shape during femtosecond laser ablation of dielectrics through non-thermal processes (the Coulomb explosion and electrostatic ablation). The predicted ablation depths and shapes in fused silica, by using 1) the plasma model only and 2) the plasma model plus the two-temperature equation, are both in agreement with published experimental data. The widely-used assumptions for threshold fluence, ablation depth, and shape in the plasma model based on free electron density are validated by the comparison study and experimental data.
L. Jiang and H. Tsai, "Materials Removals During Femtosecond Laser Non-Thermal Ablation of Dielectrics," Proceedings of IMECE2006 2006 ASME International Mechanical Engineering Congress and Exposition, American Society of Mechanical Engineers (ASME), Nov 2006.
Mechanical and Aerospace Engineering
Keywords and Phrases
Insulating Materials; Insulators; Surgical Laser Destruction
Article - Conference proceedings
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