FRACTURE PLANE OF CRUCIFORM SPECIMEN IN BIAXIAL LOW-CYCLE FATIGUE - ESTIMATE BY VARIANCE METHOD AND EXPERIMENTAL-VERIFICATION

This paper presents the variance method of determining the fracture pl ane under random multiaxial stress states. The fracture plane was esti mated analytically by the variance method with the three fatigue crite ria. The estimated fracture planes were compared with experimental res ults using type SUS 304 and 1Cr-1Mo-1/4V steel cruciform specimens. Th e variance method with the maximum normal strain criterion, by neglect ing the strain in direction in which no external forces act, could est imate the actual fracture planes of cruciform specimens in high temper ature biaxial low cycle fatigue.