MICRO-BRANCHING AS AN INSTABILITY IN DYNAMIC FRACTURE To appear in the proceedings of the IUTAM conference (Cambridge, 1995) MICRO-BRANCHING AS AN INSTABILITY IN DYNAMIC FRACTURE
نویسندگان
چکیده
Experiments in brittle, amorphous PMMA indicate that the process of dynamic fracture is governed by a micro-branching instability. At a critical velocity, vc, a single crack undergoes an abrupt, well-defined transition to microscopic crack branching. As a result, the velocity of the crack develops oscillations, the mean acceleration decreases and structure is formed on the fracture surface. Beyond vc the total fracture surface created is a linear function of the energy release rate. Micro-branch profiles follow a power law and develop into macroscopic crack branching.
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