Fracture toughness of cast ferritic steel applying local approach

Fracture characteristics prediction with temperature dependence has been made and experimentally proved for cast manganese steel. The approach is based on computer simulation of the crack nucleus formation and unstable microcrack equilibrium in polycrystalline metal. Results of low-temperature tests of smooth tensile specimens, tensile specimens with circumferential U and V notches, pre-cracked bend specimens and tensile specimens with circumferential shallow crack have been applied. A good agreement of predicted and experimentally determined fracture toughness temperature dependence for the tested steel has been obtained.