Accession Number:

ADA162572

Title:

Fatigue Properties of Multidirectional Braided Composites.

Descriptive Note:

Final Rept.,

Corporate Author:

NAVAL AIR DEVELOPMENT CENTER WARMINSTER PA AIRCRAFT AND CREW SYSTEMS TECHNOLOGY DIRECTORATE

Report Date:

1985-02-01

Pagination or Media Count:

42.0

Abstract:

The fatigue performance of graphiteepoxy composites manufactured using a general braiding process was evaluated. Two styles of braided composites were fabricated and tested. Style I was the basic 1 x 1 braid pattern. Style II was constructed by holding half of the yarns as straight columns and braiding the rest of the yarns about the fixed yarns. Performance was compared to a 24 ply conventional laminate. Tension-tension, compression-compression and fully reversed constant amplitude fatigue tests were performed. Both style braids exhibited similar behavior, except style II had longer compression-compression fatigue life. As expected, in all fatigue conditions the braids had shorter lives than the baseline laminate. Non the less, the fatigue threshold stress levels observed for the braids as a percent of ultimate strength were similar to current laminated construction design stress values. Keywords Graphite epoxy composites Three dimensional fabric FatigueMaterials.

Subject Categories:

  • Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE