Experimental analysis of fracture criterion in general yielding fracture mechanics

摘要

The efforts made over the last three decades to understand fracture behaviour of structural materials in elastic and elasto-plastic fracture mechanics are numerous, whereas investigations related to fracture behaviour of materials in thin sheets or general yielding fracture regimes are limited in number. Engineering simulative tests are used to characterize formability and drawability of sheet metals. However, these tests do not assure consistency in quality of sheet metal products. The prevention of failure in stressed structural components currently requires fracture mechanics-based design parameters like fracture toughness or critical crack-tip opening displacement. The present study aims to fulfil this gap and generate more information and thereby increased understanding is likely to yield on fracture behaviour of sheet metals. In the present investigation, using a recently developed technique for determining fracture criteria in sheet metals, results are generated on critical CTOD and fracture toughness. At the end, it is seen that the magnitude of critical CTOD and/or critical load can be used as a fracture criterion for thin sheets.