• 제목/요약/키워드: Chemical Ablation

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Tandem laser-induced breakdown spectroscopy laser-ablation inductively-coupled plasma mass spectrometry analysis of high-purity alumina powder

  • Lee, Yonghoon;Kim, Hyang
    • 분석과학
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    • 제32권4호
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    • pp.121-130
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    • 2019
  • Alumina is one of the most important ceramic materials because of its useful physical and chemical properties. Recently, high-purity alumina has been used in various industrial fields. This leads to increasing demand for reliable elemental analysis of impurities in alumina samples. However, the chemical inertness of alumina makes the sample preparation for conventional elemental analysis a tremendously difficult task. Herein, we demonstrated the feasibility of laser ablation for effective sampling of alumina powder. Laser ablation performs sampling rapidly without any chemical reagents and also allows simultaneous optical emission spectroscopy and mass spectrometry analyses. For six alumina samples including certified reference materials and commercial products, laser-induced breakdown spectroscopy (LIBS) and laser-ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) analyses were performed simultaneously based on a common laser ablation sampling. LIBS was found to be useful to quantify alkali and alkaline earth metals with limits-of-detection (LODs) around 1 ppm. LA-ICP-MS could quantify transition metals such as Ti, Cu, Zn, and Zr with LODs in the range from a few tens to hundreds ppb.

액체의 상폭발 과정에 의한 펄스 레이저 용발률의 증진 (Enhancement of Pulsed-Laser Ablation by Phase Explosion of Liquid)

  • 김동식;이호
    • 대한기계학회논문집B
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    • 제25권11호
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    • pp.1483-1491
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    • 2001
  • Enhancement of pulsed-laser ablation by an artificially deposited liquid film is presented. Measurements of ablation rate, ablation threshold, and surface topography arc performed. Correlation between material ablation and photoacoustic effect is examined by the optical beam deflection method. The dependence of ablation rate on liquid-film thickness and chemical composition is also examined. The results indicate that photomechanical effect in the phase explosion of liquid is responsible for the enhanced ablation. The low critical temperature of liquid induces explosive vaporization with localized photoacoustic excitation in the superheat limit and increases the ablation efficiency. Experiments were carried out utilizing a Q-swiched Nd:YAG laser at near-threshold laser fluences with negligible plasma effect (up to ∼100 MW/cm$^2$).

Laser Ablation : Fundamentals and applications in Micropatterning and Thin Film Formation

  • J. Heitz;D. Bauerle;E. Arenholz;N. Arnold;J.T. Dickinson
    • Journal of Photoscience
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    • 제6권3호
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    • pp.103-108
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    • 1999
  • We present recent results on ablation mechanism, single-pulse laser micropatterning , pulsed-laser deposition(PLD) and particulates formation accompanying laser ablation, with special emplasis on polymers, in particular polymide, (PI), and polytetrafluoroethylene, (PTFE). Ablation of polymers is described on the basis of photothermal bond breaking within the bulk material. Here, we assume a first order chemical reaction, which can be described by an Arrhenius law. Ablation starts when the density of broken bonds at the surface reaches a certain critical value. Single-pulse laser ablation of polyimide shows a clear-length dependence of the threshold fluence. This experimental result strongly supports a thermal ablation model. We discuss the various possibilities and drawbacks of PLD and describe the morphology, physical properties and applications of PTFE films.

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