Glass matrix composites, dispersion-reinforced toughening

A variety of mechanisms related to the crack/inclusion interaction can be exploited to increase the toughness of dispersion-reinforced glass matrix composites. In fact, toughening rather than strengthening has frequently been the goal when developing this kind of composite systems. Toughening mechanisms are also affected by the presence of residual stresses in the material. 

One important field of application for dispersion-reinforced glass matrix composites is as biomaterials for implants and in orthopaedics. Bioactive sihcate and phosphate glasses and glass-ceramics are toughened by incorporating biocompatible second phases, for example titanium, silver or stainless steel particles or chopped fibres [20,24,54,76,77]. 

Fiber-reinforced plastics are the most successful composite materials. In spite of the poor load-bearing ability of polymeric materials, excellent mechanical properties are achieved by using fiber architectures of glass and carbon hbers in a manner similar to the reinforcement of concrete with steel rods and frames. For example, toughened polymeric materials with dispersed rubber particles in a polymer matrix exhibit high fracture energy. In composite materials, introduction of secondary materials into the matrix can improve the mechanical properties considerably. 

---