The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 13, 1992
Filed:
Jul. 03, 1991
Francis C Spicola, Portsmouth, RI (US);
Neil J Dubois, Cranston, RI (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A continuous filament is selected from among a group of appropriate types of filaments, and selection of the filament length and the filament thickness is made as well. A matrix material is selected from a group of appropriate types of matrix materials. Filaments of the selected type, length and thickness are undirectionally imbedded in the selected matrix to provide a uniaxial continuously reinforced composite. The Young's modulus, E.sub.c, and the shear modulus G.sub.c, 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. If the shape of the outline of such cross section includes at least one angular break, then the lower bound of B is applied in calculating P.sub.c. If the shape of the outline of such cross section is curvilinear in its entirety, then the upper bound of B is applied in calculating P.sub.c. A structural member subjected to load values below P.sub.c will be free from load-induced microbuckling with a high degree of certainty.