Determination of laser beam intensity to maximize amplitude of ultrasound generated in ablation regime via monitoring plasma-induced air-borne sound

  • Hogeon Seo
  • Jin-Gyum Kim
  • Sunghee Yoon
  • Kyung-Young Jhang


The laser ultrasonic technique in the ablation regime was studied for the effective excitation of ultrasound. First, the optimal laser beam intensity to maximize the amplitude of ultrasound was obtained. This is useful because the amplitude of ultrasound does not always increase as the laser beam intensity increases due to the plasma shielding effect. When the laser energy is fixed, for a steel specimen, the maximum ultrasonic amplitude is obtained at the laser beam intensity in the range of 10–20 GW/cm2. In addition, an inline method to obtain the optimal laser beam intensity was proposed based on the phenomena that the amplitude of the air-borne sound induced by plasma is inversely proportional to the amplitude of the generated ultrasound. Experimental results verified the usefulness of the proposed method by showing that the amplitude of ultrasound reached its maximum when the plasma-induced airborne sound disappeared.


Ablation Laser ultrasound Plasma shield Plasma-induced air-borne sound Sensitivity correction 


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Copyright information

© Korean Society for Precision Engineering and Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Hogeon Seo
    • 1
  • Jin-Gyum Kim
    • 2
  • Sunghee Yoon
    • 1
  • Kyung-Young Jhang
    • 3
  1. 1.Department of Mechanical Convergence EngineeringHanyang UniversitySeoulSouth Korea
  2. 2.Division of Reactor LicensingKorea Institute of Nuclear SafetyDaejeonSouth Korea
  3. 3.School of Mechanical EngineeringHanyang UniversitySeoulSouth Korea

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