The Effects of through the Thickness Delaminations on Curved Composite Panels.
Abstract
The buckling loads of 8-ply A54/3501-6 graphite/epoxy delaminated cylindrical panels were determined experimentally. The delaminations fabricated into the laminate, with mylar and teflon inserts, were indicative of low velocity projectile impact damage. The mylar and teflon inserts caused partial and total delaminations, respectively. Two types of delaminations were used; namely, eccentric, off mid-surface, and mid-surface. The eccentric delaminations were placed progressively through the thickness of the laminate. STAGSC-1 finite element computer code results for undelaminated composite panels were compared to the experimental results to obtain a percent strength degradation. The experimental testing was accomplished by the Air Force Flight Dynamics Laboratory. The test device provided boundary conditions of clamped top and bottom edges and simply supported vertical sides. Two destructive techniques, stereo x-ray and deply, were used to determine the total delaminated areas and locations. Based in part on these results, one equivalent delamination was obtained corresponding to the total area of the multiple partial delaminations. The panels with multiple delaminations were found to be approximately 5 % weaker than a single delaminated area of the same total size. Keywords: Composites, Cylindrical panels, Though the thickness delaminations, Experimental shell analysis, Finite elements STAGSC-1.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1985
- Accession Number
- ADA164110
Entities
People
- Blaise A. Horban
Organizations
- Air Force Institute of Technology