Accession Number : ADD015212

Title :   Method Fabricating Load-Bearing Composites Free from Microbuckling Deformation Up to a Predetermined Load.

Descriptive Note : Patent application filed, 3 Jul 91,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Dubois, Neil J

Report Date : 03 Jul 1991

Pagination or Media Count : 20

Abstract : A method fabricating a continuous filament reinforced composite free from microbuckling deformation up to a predetermined load with a high degree of certainty is disclosed. A continuous filament is selected from among a group of appropriate types of filaments. A matrix material is selected from a group of appropriate types of matrix materials. Selected filaments are undirectionally embedded in the selected matrix to provide a uniaxially continuously reinforced composite. The Young's modulus and the shear modulus are calculated for the composite. Mathematical formulas are provided for calculation of upper and lower bounds of transverse stiffness, B. A mathematical formula is provided for calculation of critical comprehensive stress, P sub c. Transverse stiffness, B, is involved as one of the factors in this formula. Either one or the other of the upper bound of B or the lower bound of B are alternatively applied in calculating P sub c depending upon a consideration related to the shape of a cross section of the structural member into which the composite is to be formed. A structural member subjected to load values below P sub c will be free from load-induced microbuckling with a high degree of certainty.

Descriptors :   COMPOSITE MATERIALS, CROSS SECTIONS, FILAMENTS, FORMULAS(MATHEMATICS), LOADS(FORCES), MATRIX MATERIALS, MODULUS OF ELASTICITY, REINFORCING MATERIALS, SHEAR MODULUS, STIFFNESS, STRESSES, STRUCTURAL COMPONENTS, TRANSVERSE

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE