High Durability Missile Domes.
Abstract
Magnesium oxide optical surfaces were protected from degradation due to moisture by any of several sputtered coatings. The coatings are of optical quality and were unaffected by rainfield tests at 256 m/sec. Highly transparent flat plate samples of polycrystalline magnesium aluminum oxide (spinel) were fabricated by the fusion casting technique. The best samples have a 2:1 Al2O3 composition and measure more than 50 mm across and 3 mm thick. Beams of polycrystalline and single crystal alumina-rich spinel were deformed in three-point loading at approximately equal to 1750 C. Applied stresses between 20 and 70 MN/sq m produced up to right angle bends, suggesting the feasibility of forging flat plates of spinel into hemispherical dome shapes. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1977
- Accession Number
- ADA048497
Entities
People
- E. Maguire
- J. Pappis
- R. Gentilman
Organizations
- RTX