Modeling Interface Failure in Fiber-Composites

Author

Andrew J. Craig

Degree Type

Honors Capstone Project

Date of Submission

Spring 5-1-2005

Capstone Advisor

Dr. Alan J. Levy

Honors Reader

Dr. John F. Dannenhoffer III

Capstone Major

Mechanical and Aerospace Engineering

Capstone College

Engineering and Computer Science

Audio/Visual Component

no

Capstone Prize Winner

no

Won Capstone Funding

no

Honors Categories

Sciences and Engineering

Subject Categories

Aerospace Engineering | Multi-Vehicle Systems and Air Traffic Control

Abstract

Interface failure has been studied in depth for more than the past twenty years due to its significant impact on the application of composite materials. The objective of this work is to investigate the role of the interface in the mechanical response of fiber-matrix composite materials subjected to an applied load. To do this, a single composite cylinder consisting of a rigid core, the fiber, and an elastic annulus, the matrix, with an interface of vanishing thickness separating them, is considered as the first step in what will later be representative of a composite material. Three non-linear, Needleman-type, force-separation relations are considered for modeling the interface: (i) bilinear, (ii) exponential, and (iii) viscoelastic Kelvin model. For certain parameter values, the first two models demonstrate abrupt, discontinuous interfacial separation behavior. The third model, which consists of a bilinear elastic element coupled with a linear viscous element, is introduced to eliminate the abrupt separation phenomena produced by (i) and (ii). Visual simulations representing the separation of the matrix from the fiber are presented for each interface force-separation relation, using the symbolic math program, MAPLE. Transitioning from a single composite cylinder to a fiber-reinforced composite with a microstructure consisting of varying size composite cylinders extends the development of the mechanics of interface failure to real composite materials.

Recommended Citation

Craig, Andrew J., "Modeling Interface Failure in Fiber-Composites" (2005). Renée Crown University Honors Thesis Projects - All. 698.
https://surface.syr.edu/honors_capstone/698

Creative Commons License

This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.