Fiber/matrix interface composites

Bianchi V, Goursat P, Menessier E, Carbon-fiber-reinforced YMAS glass-ceramic-matrix composites - IV. Thermal residual stresses and fiber/matrix interfaces, Composites Sci Technol, 58(3-1), 409-418, 1998. 

Pegoretti A and DiBeiiedetto A T (1998) Measurement and analysis of stress transfer aud toughness at fiber-matrix interface, Composites Part A 29A 1063-1070. 

The mechanical properties of composites based on the fibers discussed depend not only on the characteristics of the fibers but also on those of the matrix itself as well as on the fiber—matrix interface. 

The selection of a suitable matrix for a composite material involves many factors, and is especially important because the matrix is usually the weak and flexible link in all properties of a two-phase composite material. The matrix selection factors include ability of the matrix to wet the fiber (which affects the fiber-matrix interface strength), ease of processing, resulting laminate quality, and the temperature limit to which the matrix can be subjected. Other performance-related factors include strain-to-failure, environmental resistance, density, and cost. 

As is known of glass fiber-reinforced plastics, the mechanical and physical properties of composites, next to the fiber properties, and the quality of the fiber matrix interface, as well as the textile form of the reinforcement primarily depend on the volume content of fibers in the composite. 

Tests by Gatenholm et al. [8,10] on PHB-HV copolymers containing cellulose fibers (for example, the tradenamed Biopol) show that the mechanical properties of these systems are determined by the fiber and the fiber matrix interface on the one hand, and on the other hand by the composition of the matrix, that is, of HV proportion in the matrix. At an increased proportion of HV, the stiffness of the composite is reduced up to 30%, whereas elongation at break increases until about 60%. 

A discontinuous fiber composite is one that contains a relatively short length of fibers dispersed within the matrix. When an external load is applied to the composite, the fibers are loaded as a result of stress transfer from the matrix to the fiber across the fiber-matrix interface. The degree of reinforcement that may be attained is a function of fiber fraction (V/), the fiber orientation distribution, the fiber length distribution, and efficiency of... 

In fiber-reinforced composites the deformation of the matrix is then used to transfer stresses by means of shear tractions at the fiber-matrix interface, to the embedded high-strength fibers. On the other hand, fibers retard the propagation of cracks and thus produce a material of high strength. 

Marshall, P. and Price, J. (1991). Fiber/matrix interface failure controlled by a critical energy criterion. Composites. 22, 445-447. 

Pitkethly, M.J. and Doble, J.B. (1990). Characterizing the fiber/matrix interface of carbon fiber-reinforced composites using a single fiber pullout test. Composites 21, 389-395. 

Qiu, Y. and Schwartz, P. (1991). A new method for study of the fiber-matrix interface in composites Single fiber pull-out from a microcomposite. J. Adhesion Sci. Technol. 5, 741-756. 

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