Characterization of ductile material behaviour by J-R curves

An improved characterization of ductile material behaviour by J-R curves and by derived fracture toughness parameters is a major goal of the activities of EGF Task Group I "Elastic Plastic Fracture Mechanics". The state-of-the-art in applying single specimen tests based on potential drop and partial unloading compliance methods is described and discussed in terms of accuracy and reliability. The quality of test results allows for separation of procedural and material variations, to get down to the problem of geometry dependence of J-R curves, and for updating and finalizing the procedures of ductile failure test standards