Accession Number : ADA305211

Title :   Repair Techniques for Celion/LARC-160 Graphite/Polyimide Composite Structures.

Descriptive Note : Final rept.,

Corporate Author : ROCKWELL INTERNATIONAL DOWNEY CA SPACE TRANSPORTATION SYSTEMS DIV

Personal Author(s) : Jones, J. S. ; Graves, S. R.

PDF Url : ADA305211

Report Date : JUN 1984

Pagination or Media Count : 219

Abstract : Operational feasibility of the next generation of reusable space vehicles requires the development of a structural material system that is significantly lighter than the conventional aluminum structure presently employed on the Space Shuttle orbiter. Utilization of graphite filament reinforced polyimide matrix composite material, capable of 600 F service, can achieve this goal. The large stiffness-to-weight and strength-to-weight ratios of graphite composite in combination with the 6OO F structural capability of the polyimide matrix can reduce the total structure/TPS weight by 20-30 percent. In order for the graphite/polyimide (GR/PI) material system to be acceptable for use in advanced space transportation systems, it is necessary that manufactured components be maintained in a safe and economical manner. It is inevitable that with planned usage of OR/PI structural components, damage will occur either in the form of intrinsic flaw growth or mechanical damage. Research and development programs were initiated to develop repair processes and techniques specific to Celion/LARC-l60 OR/PI structure. The study was directed toward highly loaded and lightly loaded compression critical structures for factory type repair. Repair processes included cocure and secondary bonding techniques applied under vacuum plus positive autoclave pressure. Viable repair designs and processes were developed for flat laminates, honeycomb sandwich panels, and hat-stiffened skin-stringer panels. The repair methodology was verified through structural element compression tests at room temperature and 3l5 C (600 F).

Descriptors :   *SPACECRAFT, *COMPOSITE MATERIALS, *LAMINATES, *SPACE TRANSPORTATION, *ADHESIVES, *POLYIMIDE RESINS, NONDESTRUCTIVE TESTING, STIFFNESS, FABRICATION, COMPOSITE STRUCTURES, GRAPHITE, MATRIX MATERIALS, OPERATIONAL EFFECTIVENESS, REPAIR, ALUMINUM, BONDED JOINTS, SPACE SHUTTLES, BONDING, STRENGTH WEIGHT RATIO, STRUCTURAL COMPONENTS, COMPRESSIVE PROPERTIES, ADHESIVE BONDING, SANDWICH PANELS, HONEYCOMB STRUCTURES, PEEL STRENGTH.

Subject Categories : Adhesives, Seals and Binders
      Laminates and Composite Materials
      Plastics
      Unmanned Spacecraft
      Manned Spacecraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE