Estimation of fracture toughness using miniature chevron-notched specimens

摘要

An approach for determining fracture toughness of materials using miniature chevron-notched specimens is reported here for the first time. An outline of the principle and the experimental procedure for the test is depicted using results generated on eutectoid steel. Fracture toughness values of soft annealed and fully annealed eutectoid steels with inter-lamellar spacing 167 nm and 549 nm are found to be 76 MPa m～(1/2) and 56 MPam～(1/2), respectively. The estimated fracture toughness values from miniature specimens are found to be in good agreement with the ones reported for similar bulk materials.