Measurement of dynamic elastic-plastic fracture toughness parameters using various methods

Two improved impact testing facilities are used for the dynamic fracture toughness evaluation of precracked Charpy V-notch specimens. The methods of single specimen acoustic emission and crack mouth opening displacement testing are assumed to indicate the initiation points of stable crack growth. Thus, the dynamic ductile initiation J integral JId can be derived. It was shown that the toughness JId of the heat-resistant steel 10CrMo9.10 cannot be approximated by the J value at the maximum of the load deflection curve