Interlaminar shear strength of an aircraft wing made of graphite-epoxy laminate is significantly increased by embedding thin steel wires in preselected locations of high stress in alternating rows + - 45 degrees to the plane of the laminate before it is cured. This cross wire reinforcement prevents brittle delamination, arrests propagation of delamination and reduces scatter of interlaminar strength.
An extensive series of creep tests were made on bulk epoxy speci-mens (Narmco 1004) and on three types of laminated specimens made from a composite (Modmor II 5206) with this epoxy as its matrix. Tests were made at a wide range of temperatures and stresses. The resulting laminate creep curves were compared with calcu-lations employing a modified version of a computer program deve- loped in connection with earlier work on ...
A graphite epoxy composite wing for the BQM-34E unmanned supersonic aerial target vehicle has been successfully static tested to 100 percent design limit load at the NAVAIRDEVCEN.
A graphite-epoxy composite wing for the BQM- 34E unmanned supersonic aerial target vehicle has been successfully static tested to 100 percent design limit load at the NAVAIRDEVCEN (Naval Air Development Center). Test procedures and results are described, and comparisons between analytical predictions and recorded values are presented. Good correlation between analysis and test was observed. On the basis of this test, the composite wing is considered statically quali-fied for flight. ...
A general method is presented for determining the displacement and stress fields within axially-symmetric elastic bodies due to prescribed internal loadings and boundary conditions. The solutions obtained satisfy the exact three-dimensional equations of linear elasticity. All internal forces of the problem are applied at corresponding locations in an infinite body. The effects of these forces on the infinite body are determined using Kelvin's solution for a point force. A distribution ...
An analytical method is presented to predict the viscoelastic creep and relaxation behavior of filamentary reinforced angle-ply laminates. Analytical methods based upon micromechanics are used to predict the time dependent properties of unidirectional fiber reinforced composite materials (i.e., relaxation moduli and creep compliances). A LINEAR, VISCOELASTIC, ORTHOTROPIC LAMINATE THEORY (including thermal effects) is mathematically formulated. A computational method is presented to solve the resulting convolution integral equations. Numerical results for ...
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