Response of Graphite Composites to Laser Radiation
Abstract
Experimental and analytical investigations of the response of graphite-epoxy composite tensile coupons to laser radiation have been performed. Three different 5208/T300 laminates were used to compare stacking sequence effects, three thicknesses of one of the laminates were studied, and an aluminum alloy was employed for comparison purposes. The experimental program has concentrated on laser-induced controlled-depth damage, physical characterization of the damaged area, and residual tensile strength measurements. Thermal response measurements were conducted on selected specimens to aid in assessing the damage mechanisms and to formulate a penetration model. An additional feature of the experiments included laser exposure of preloaded specimens to determine the requisite energy-to-fracture. By considering the material response in three different incident intensity ranges, there was delineated the interactions which occur and formulated models which predict the thermal response, mass ablation, and penetration in those ranges. The strength retention for partially-penetrated, laser-damaged composites is describable in terms of fracture-mechanics-based predictions at all but the lowest intensity investigated, where essentially only resin sublimation occurs. Painted aluminum is more susceptible than composites to damage at high intensity, while strength retentions are similar at intermediate intensities.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1977
- Accession Number
- ADA041283
Entities
People
- H. G. Carter
- J. R. Eisenmann
- K. G. Kibler
Organizations
- General Dynamics