Diseño y Construcción de una Mordaza para Ensayo de Tracción Oblicua para Materiales Compuestos Laminados con Funcionalidad de acople a Máquina del Laboratorio de Esfuerzos de la FIM de la EPN

Abstract

The present investigation has the objective of design and constructs four grips to develop off-axis tests on laminated composite materials, which were coupled to the existing universal testing machine in new materials laboratory at FIM of EPN. A study was made of the existing alternatives, the limitations and problems when carrying out this type of test. The concurrent design methodology was applied to establish the design specifications and define alternatives. For the design of the elements, calculations and a simulation were carried out to evaluate both its resistance and functionality to eliminate the undesired effect of bending at the ends of the specimen. Composite specimens were fabricated with the fibers oriented ten degrees respect to the line of action of force. Subsequently, the shear unit deformation in the direction of the reinforcing fiber was deduced through the measurements made with a 45°-rectangular strain gage rossettes. This capacity allowed the sample to reach a uniform deformation field and, therefore, is suitable for the characterization of mechanical properties of unidirectional composites specially to obtain the shear modulus in orthotropic materials in an experimental way.