Testing Methods for Energy Absorption of Kevlar/Epoxy
Abstract:Twenty flat‐plate specimens and six tubes were crushed under quasi‐static conditions. The energy absorbency of each specimen was measured resulting in a value of the specific sustained crushing stress (SSCS). The plates and tubes were manufactured from 49/CYCOM 919 Kevlar/epoxy fabric and had the same layup providing a common laminate for comparison. The flat plates were scored to facilitate the fracture of the laminate along the constraints during crushing. Two different widths of flat plates were tested to determine the effect of the end conditions of the testing fixture on the observed energy absorbency. The results for the flat‐plate specimens indicate that the energy absorbency per unit thickness is independent of the specimen test width while maintaining the crushing mechanism. Thus, the edges of the testing fixture provided no significant contribution to the energy absorbency. Furthermore, the results indicate that the flat‐plate geometry provides comparable energy absorption values to those of the tube geometry.
Document Type: Research Article
Affiliations: Alfred Gessow Rotorcraft Center, Department of Aerospace Engineering, University of Maryland, College Park, Maryland 20742
Publication date: July 1, 1999
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