Acoustic emission study on the effect of notch shape and temperature on elastic energy release during impact testing of 17Mn1Si pipe steel

Abstract Main fracture mechanisms are determined in 17Mn1Si steel during impact Charpy testing of specimens with three types of notches at different test temperatures covering ductile-to-brittle transition. The influence of the notch shape on the amount of expended mechanical energy (according to the loading diagram) and released elastic energy (according to the recorded acoustic emission signal) is analyzed. A combined application of fracture mechanics and acoustic emission methods is proven effective for better understanding of dynamic fracture and ductile-to-brittle transition from the viewpoint of energy-based approaches to crack initiation and propagation. It is suggested that the link between the AE signal and the ductile-to-brittle transition in dynamic loading can be established to develop a tool for in situ characterization of the fracture process.