Predicting the Average Absorptance During the Continuous Wave Laser Penetration of Painted Alloys.
Abstract
The average surface absorptance for the penetration of painted metal targets by a continuous wave laser is derived theoretically based on the assumption that the paint is thermally thick and is removed by a steady-state vaporization process. The heat required to melt through a painted metal target is postulated to enter the target during two phases: (1) Heat is conducted into the metal while the paint is being vaporized at steady-state from its surface; (2) After paint removal, heat is added to metal until melt-through by the laser radiation impinging on the resulting unpainted metal surface. A heat balance on the paint and metal plate permits the definition of an average surface absorptance for the entire melt-through event. This average absorptance is shown to be a function of the laser beam intensity, paint and metal thicknesses and the thermal properties of both paint and metal. The predicted importance of these variables is discussed, and the calculated absorptances compared with available absorptance data from actual melt-through experiments. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1977
- Accession Number
- ADA061607
Entities
Organizations
- Air Force Research Laboratory