Skip to Main content Skip to Navigation
Journal articles

Measurement of laser absorptivity for operating parameters characteristic of laser drilling regime

Abstract : Laser drilling in the percussion regime is commonly used in the aircraft industry to drill sub-millimetre holes in metallic targets. Characteristic laser intensities in the range of 10 MW cm−2 are typically employed for drilling metallic targets. With these intensities the temperature of the irradiated matter is above the vaporization temperature and the drilling process is led by hydrodynamic effects. Although the main physical processes involved are identified, this process is not correctly understood or completely controlled. A major characteristic coefficient of laser-matter interaction for this regime, which is the absorptivity of the laser on the irradiated surface, is still unknown, because of the perturbing effects due to laser beam geometrical trapping inside the drilled hole. So, by using time resolved experiments, this study deals with the direct measurement of the variation of the intrinsic absorption of aluminium, nickel and steel materials, as a function of the incident laser intensity up to 20 MW cm−2. We observe that for this incident intensity, the absorptivity can reach up to 80%. This very high and unexpected value is discussed by considering the microscopic behaviour of the heated matter near the vapour-liquid interface that undergoes possible Rayleigh-Taylor instability or volume absorption
Complete list of metadatas

Cited literature [14 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-00794960
Contributor : Compte de Service Administrateur Ensam <>
Submitted on : Thursday, February 28, 2013 - 10:26:45 AM
Last modification on : Friday, July 17, 2020 - 2:54:12 PM
Long-term archiving on: : Sunday, April 2, 2017 - 5:47:17 AM

File

Measurement_of_laser_absorptiv...
Files produced by the author(s)

Identifiers

Citation

Matthieu Schneider, Laurent Berthe, Rémy Fabbro, Maryse Muller. Measurement of laser absorptivity for operating parameters characteristic of laser drilling regime. Journal of Physics D: Applied Physics, IOP Publishing, 2008, 41 (15), pp.6. ⟨10.1088/0022-3727/41/15/155502⟩. ⟨hal-00794960⟩

Share

Metrics

Record views

435

Files downloads

2643