A J Integral Analysis for the Compact Specimen, Considering Axial Force as Well as Bending Effects

Abstract

An important fracture mechanics problem is the determination of fracture toughness values with small specimens that fail after yielding. The J integral has an explicit meaning in terms of notch tip conditions in the plastic range and can be calculated from a single specimen test data. In this paper, an improved J integral analysis is developed for the compact specimen by considering the combined loading that exists on the net section. The analysis agrees with linear elastic fracture mechanics in the elastic range and gives a result close to that given by the equivalent energy method in the plastic range.