Premium
THE EFFECT OF MEAN STRESS ON MIXED MODE (I + III) FATIGUE THRESHOLDS
Author(s) -
Yates J. R.,
Mohammed R. A.
Publication year - 1993
Publication title -
fatigue and fracture of engineering materials and structures
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.887
H-Index - 84
eISSN - 1460-2695
pISSN - 8756-758X
DOI - 10.1111/j.1460-2695.1993.tb00744.x
Subject(s) - mode (computer interface) , mixed mode , materials science , structural engineering , slit , composite material , stress (linguistics) , range (aeronautics) , engineering , physics , optics , linguistics , philosophy , computer science , operating system
— Mode I, mode III and mixed mode (I + III) fatigue crack growth threshold tests have been performed on a 3.5% NiCrMoV steel at a range of mean stresses corresponding to load ratios R = 0.06 to 0.5. Angled slit three point bend specimens were used for mixed mode (I + III) tests, circumferentially slit round bars for mode III tests and conventional three point bend specimens for mode I tests. Test results were divided into those specimens which had failed and those in which no extension of the initial slit had occurred. The results were compared with the response predicted by two existing mixed‐mode threshold models. It was found that a model based on the magnitude and direction of mode I crack opening gave results which were in better agreement with the experimental results than a model based on branch crack formation.