Page 23 - Engineered Interfaces in Fiber Reinforced Composites

6 Engineered interfaces in fiber reinforced composites

chemical bonding, reaction bonding, and exchange reaction bonding (Kim and Mai,
1993), which are schematically shown in Fig. 2.1 and discussed in the following
sections. In addition to the major mechanisms, hydrogen bonding, van der Waals
forces and other low energy forces may also be involved. All these mechanisms take
place at the interface region either in isolation, or, most likely, in combination to
produce the final bond. Reviews on these major mechanisms can be found in many
references including Scolar (1974), Wake (1978), Kinloch (1980, 1982), Hull (1981),
Adamson (1982) and Kinloch et al. (1992) for polymer matrix composites; Metcalfe
(1974) for metal matrix composites (MMCs); and Naslain (1993) for ceramic matrix
composites (CMCs). More recently, mechanisms and mechanics modeling of
interfaces in cementitious composites have received a lot of attention (see for
example, Maso, 1993; Cotterell and Mai, 1996).

Fig. 2.1. Interface bonds formed (a) by molecular entanglement; (b) by electrostatic attraction; (c) by
interdiffusion of elements; (d) by chemical reaction between groups A on one surface and groups B on the
other surface; (e) by chemical reaction following forming of a new compound(s), particularly in MMCs;
(f) by mechanical interlocking. After Hull (1981) and Naslain (1993).