A clear demonstration of the potential of ribbon shaped rein forcements in composite materials applications is presented. From a micromechanics analysis, supported by experimental results, we find that ribbon reinforcement offers superior stiffness properties in the plane of the lamina. The macromechanics analysis intro duces the concept of a hybrid composite in which the engineer may combine the outstanding strength properties of fibers with the superior stiffness properties offered by ribbon reinforcements. It is pointed out that the low strength observed for glass-ribbon com posites is a consequence of fabrication procedures and does not correspond to the theoretical limiting strength of ribbon rein forcements.
The primary requirements of a desirable shear test method include the ability to introduce a well-defined state of stress in the specimen, capability of determining both shear modulus an~shear strength with one test of a single specimen, use of a minimum a~ou?~of mate~ml per specl?1en, ease of specimen fabrication and preparation, and simplicity of tesh.ng. The solid-rod torsion test is shown to fulfill these requirements. !\~ethods a?d equ~pment de~eloped for both the fabrication and testing of specimens are discussed m detail. Expenmental data obtained by utilizing the solid-rod torsion test on several different, composite-material systems are presented. These results are then compared with data obtained by utilizing other shear-property test methods.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.