STABILITY CHARACTERIZATION OF REFRACTORY MATERIALS UNDER HIGH VELOCITY ATMOSPHERIC FLIGHT CONDITIONS. PART V. VOLUME I. ADDITIONAL STUDIES.
Abstract
The oxidation of refractory borides, graphites and JT composites, hypereutectic carbide-graphite composites, refractory metals, coated refractory metals over the extensive spectrum of environmental conditions encountered during reentry or high velocity atmospheric flight, as well as those employed in furnace tests was studied. Male and Female configurations of simple nosetip and leading edge structures composed of boride components threaded into coated tantalum holders have been designed and tested successfully for 1800 seconds with no cracking at Mach 3.2 at 520-548 BTU/sq ft sec, 8550 BTU/lb and 0.063 atm. Total oxidation was 29-36 mils at temperatures near 4700F for these tests, or 30-60 times less than comparable recessions for tungsten or graphite. In addition a six cycle exposure of a male nosetip was successfully performed including a 100 BTU/sq ft sec exposure, a 460 BTU/sq ft sec segment followed by four 200 BTU/sq ft sec cycles with a total oxidation depth of 10 mils. No other materials system known currently can match this performance in heat flux, temperature and oxidation resistance and fabricability. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1971
- Accession Number
- AD0885295
Entities
People
- Harvey Nesor
- Larry Kaufman