FEASIBILITY DEMONSTRATION OF PYROLYTIC GRAPHITE COATED NOZZLES

Abstract

Pyrolytic graphite coatings have been found to be highly erosion resistant under severe rocket nozzle conditions. The objective of this program was to demonstrate the feasibility of such coatings for nozzles up to 2.3-inch diameter in firings at 700 psi with a 6550 F propellant. This objective was accomplished. Stress and thermal analyses were carried out in support of the design, fabrication, and motor testing of nozzles of both 1.1-inch and 2.3-inch diameter. Thermal analysis indicated the potential of pyrolytic graphite coatings for lightweight nozzle designs. The results of the stress analyses for coated composites were correlated with experimental evidence of delamination cracking in the coatings. Critical stress levels were identified for both radial tension in the coating and axial tension in the substrate. The deposition process was improved to produce crack-free coatings 50-mil-thick on conventional graphite substrates and 100-mil thick on a fabrous graphite substrate.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1965
Accession Number
AD0368227

Entities

People

  • Edwin F. Ford
  • Eugene L. Olcott
  • James D. Batchelor

Organizations

  • ARCO

Tags

Communities of Interest

  • Advanced Electronics
  • Weapons Technologies

DTIC Thesaurus Topics

  • Coatings
  • Composite Materials
  • Fabrication
  • Geometry
  • Materials
  • Materials Processing
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Modulus Of Elasticity
  • Physical Properties
  • Plastic Explosives
  • Rocket Engines
  • Shear Modulus
  • Stress Analysis
  • Stress Strain Relations
  • Stresses

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Reinforced Composite Materials
  • Surface Engineering/Surface Coating Technology.