On the Length of Crack Jump during Subcritical Growth

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Department of Mechanical Engineering-Engineering Mechanics


The stepwise growth of a crack in elastoplastic materials under subcritical conditions is considered by developing a model for the individual jumps. The method is based on the concept of the process zone which was precisely defined in an earlier paper (Engng Fracture Mech.26, 491-503). It is shown that the length of the jump is given explicitly in terms of the geometric and physical characteristics of the process zone, external loading and environmental conditions. The environment of interest can be either a high temperature or a chemical agent, with emphasis being placed on hydrogen-assisted cracking. Two main results are established within this discrete modelling approach to crack motion. First, a physically based definition of a continuous velocity for the crack tip is possible; and, second, the structure of the velocity vs stress intensity factor curve is theoretically established.

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© 1987

Publication Title

Engineering Fracture Mechanics