Thermal coupling on aluminum alloy surfaces in vacuum at 10.6 micrometer
Abstract
The experimental measurement of the thermal coupling of a pulsed CO2 laser to duraluminium targets was carried out at a low-pressure level in ambient air at P sub 0 = 0.04 torr. The laser pulses of 10 microsec, E sub 0 energy between 1 and 10 Joules are focused on a 3 sq mm target area. The thermal coupling coefficient is close to 0.3 and is independent from the value of E sub 0. The bulk vaporization followed by the breakdown appears in isolated sites. The importance of the infrared absorptivity enhancement of the metal when it melts, and the presence of surface defects or incident radiation non-homogeneities can explain this phenomenon.
- Publication:
-
AIAA, 18th Thermophysics Conference
- Pub Date:
- June 1983
- Bibcode:
- 1983thph.confR....B
- Keywords:
-
- Aluminum Alloys;
- Carbon Dioxide Lasers;
- Laser Target Interactions;
- Metal Surfaces;
- Metal Vapors;
- Thermodynamic Coupling;
- Coupling Coefficients;
- Infrared Absorption;
- Pulsed Lasers;
- Temperature Effects;
- Vacuum;
- Vaporizing;
- Lasers and Masers