A specimen of a 4340 steel alloy with a plane strain fracture toughness of 54.8MPam is exposed to a stress of 1030MPa. If the largest surface crack is 0.5mm long, what is the critical stress of this specimen? Assume the parameter Y has a value of 1.0 . Will this specimen experience fracture? Critical stress (MPa)= Specimen fractures ( yes / no )= A specimen of a 4340 steel alloy with a plane strain fracture toughness of 54.8MPam is exposed to a stress of 1030MPa. If the largest surface crack is 0.5mm long, what is the critical stress of this specimen? Assume the parameter Y has a value of 1.0 . Will this specimen experience fracture? Critical stress (MPa)= Specimen fractures ( yes / no )=