Computer simulation of the Charpy V-Notch toughness test

Abstract

We calculated the impact of a striker with the ASTM Type A Charpy V-Notch specimen. We used an elastic-plastic constitutive law with J 2-flow theory and isotropic hardening to model A-533 Grade B class 1 steel at 100°C. Large strain and rotation are accounted for. We found that the notch stress-strain state was independent of the three-point loading type (round- or flat-tip striker or pressure push) and was most strongly correlated with notch-opening displacement. The dynamic stress-strain state at the time of fracture initiation was obtained by comparing the calculated deformed shape with that obtained in interrupted Charpy-V-notch tests where cracking had started. This time agreed with a computed prediction of fracture initiation obtained using a computer model of material damage. Cracking starts at the notch at about 40% of the maximum load found in an instrumented Charpy test. We have also calculated the distribution and partition of specimen energy. Adiabatic heating and strain rate are discussed.