Electron-Beam-Induced Damage in Paint Samples.
Abstract
Electron-beam-induced damage was investigated in paints that are being developed as protective coatings for missiles. The electron-beam testing of the paints had four objectives: (1) to determine, by establishing the damage threshold and mode, if low-level stress would cause pop-off, (2) to determine the impulse as a function of fluence, (3) to determine the mass loss as a function of fluence, and (4) to determine the Gruneisen parameter for the paints. The tests showed that the damage mode was not low-stress-level pop-off, but spall at a fluence of 30 to 40 cal/sq cm incident on the filters. The tests showed also that the impulse as a function of fluence is steplike. At 25 to 30 cal/sq cm fluence, the impulse is too small to be measured, but at 40 cal/sq cm it increases to about 1 kilotap and remains essentially at that level at higher fluences. By using stress-time measurements, the Gruneisen parameter was calculated to be 0.37 if crushup and plastic work are neglected. This value, therefore, represents a lower bound on the parameter. Both impulse and the mass-loss data showed large variations at each fluence level. Further analysis indicated that these data variations were caused by experimental problems resulting primarily from the use of the filters and the wide variation in the response of the different paint samples. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1976
- Accession Number
- ADA032682
Entities
People
- Dale R. Schallhorn
- Gary L. Skillington
- Robert B. Oswald Jr.
- Timothy R. Oldham
- William D. Scharf
Organizations
- Harry Diamond Laboratories