Accession Number : ADA301800

Title :   Strength of Graphite/Epoxy Bolted Wing-Skin Splice Specimens Subjected to Outdoor Exposure Under Constant Load and Yearly Fatigue Loading.

Descriptive Note : Technical paper,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER

Personal Author(s) : Wichorek, Gregory R. ; Crews, John H., Jr

PDF Url : ADA301800

Report Date : JAN 1986

Pagination or Media Count : 36

Abstract : The results of an experimental study to provide long-term durability data on detailed full-scale graphite/epoxy wing-skin joint designs under environmental exposure and cyclic loading associated with commercial transport aircraft are reported. The specimens consisted of a single-row bolt configuration fabricated from T300/5208 and a double-row bolt configuration fabricated from T300/5209. The unpainted specimens were exposed to the outdoor environment under a sustained tensile load, and at yearly intervals, they were subjected to fatigue loading. Experimental results showed a slight reduction in residual tensile strength for both graphite/epoxy joints under the exposure times and fatigue loadings reported. A 7.5-percent decrease in residual strength was observed for the T3OO/52O% single-row joint after 5 years exposure and two lifetimes of fatigue loading. A 5.3-percent decrease in residual strength was observed for the T300/5209 double-row joint after 7 years exposure and 2.8 lifetimes of fatigue loading. The 5208 epoxy material was more susceptible to degradation by ultraviolet radiation than the 5209 epoxy material

Descriptors :   *COMMERCIAL AIRCRAFT, *WINGS, *TRANSPORT AIRCRAFT, *SKIN(STRUCTURAL), *GRAPHITE EPOXY COMPOSITES, TENSILE STRENGTH, LOADS(FORCES), FATIGUE(MECHANICS), SPLICES, CYCLIC LOADS, BOLTED JOINTS.

Subject Categories : Commercial and General Aviation
      Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE