E-Glass/DGEBA/m-PDA Model Composites: Time Dependent Failure in a Brittle Multi-Fiber Composite
Gale A. Holmes, Walter G. McDonough
The fiber-direction properties of a unidirectional laminate are generally considered to be fiber-dominated and the elastic modulus may be predicted by the Rule-of-Mixtures approach using the respective Young's modulus of the constituents. However, the failure behavior has been qualitatively shown to be dependent on the matrix. For example, Bader in 1968 noted that composites with brittle matrices and relatively weak fiber-matrix interfacial bonding failed in a brush-like manner, while composites with comparatively strong interfaces failed by propagation of a single crack across the section, with little or no longitudinal splitting. Although the tensile strength in a unidirectional composite is mainly influenced by the fiber strength and fiber volume fraction, Bader concluded that the matrix and fiber-matrix interface influences both the strength and failure mode.Research on 2-D multi-fiber model composites has shown that the nucleation of the critical flaw that induces brittle failure is dependent on the redistribution of stress around the fiber breaks through the viscoelastic matrix. Hence, the nucleation process is time-dependent. In addition, the inter-fiber spacing has been shown to influence the mode of failure after fiber fracture. The implication of these observations on failure initiation, propagation, and energy absorption in unidirectional fibrous composites will be discussed.
Affordable Materials Technology
June 1, 2002
International SAMPE Technical Conference Proceedings
and McDonough, W.
E-Glass/DGEBA/m-PDA Model Composites: Time Dependent Failure in a Brittle Multi-Fiber Composite, Affordable Materials Technology, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=851988
(Accessed December 2, 2023)