Energy Balance in Fracture

A general approach to the quantitative characterization of fracture may now be given in terms of the energy balance required to propagate a crack or flaw. 

Griffith showed that this critical point is defined by the equation 

While correlation of fracture behavior in glassy polymers with the time-temperature relationships is receiving increasing attention [see, for example, Broutman and Kobayashi (1972), Johnson and Radon (1972), Radon (1972)], the case of rupture in elastomers is rather well developed, and is discussed briefly below. 

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