Analysis of matrix damage in single fiber composites

<p>"A unidirectional fiber-reinforced composite under a tensile load in the direction of the fibers develops equal axial strains in the fiber and the matrix, if there are no initial cracks and the fiber/matrix interface is perfectly bonded. With further increase in the load, the fiber or the matrix will crack depending on the failure strains or the fiber/matrix interface w ill debond depending on the interfacial strength. This damage of the fiber or the matrix would eventually lead to the ultimate failure of the composite. Hence it is essential to analyze the stresses and energies associated with an unidirectional composite containing matrix crack, with/without interfacial debonding. A consistent shear-lag model in cylindrical coordinates is developed to achieve this. The governing equations are solved using an eigen value technique. When a fiber is partially is debonded, compressive stresses due to resin shrinkage and difference in thermal expansion coefficient of fiber and matrix act on the fiber giving rise to friction in the debonded zone. The effect of friction has been modeled by applying constant interfacial stresses in the debond zone.</p> <p>The micro bond pull-out test is one of the methods for measuring the shear strength of the fiber/matrix interface, which is a very important property required for investigating the behavior of composites. The above-mentioned model has been applied to solve for the interfacial stresses developed during the micro bond pull-out test. It is shown that the location of the supports during the micro bond pull-out test is a very important parameter, which can alter the debond loads to a large extent as observed in the experiments"--Abstract, p. v</p>

Name thesis:degree_name

Ph. D. in Mechanical Engineering

Grantor

University of Missouri--Rolla

Year dc:date.available

2016

Author dc:creator

• Venkatakrishnaiah, Shashikumar

• Mechanical Engineering

Repository record dc:identifier

https://scholarsmine.mst.edu/doctoral_dissertations/724

OAI identifier oai:identifier

oai:scholarsmine.mst.edu:doctoral_dissertations-1726