Search results for "Fracture plane"
showing 3 items of 13 documents
Simulation investigations of the position of Fatigue Fracture Plane in materials with biaxial loads
1989
In the paper three methods of determination of the expected fatigue fracture plane position under random triaxial stress state have been presented. They are: weight function method, variance method and damage cumulation method. The weight function method for biaxial cyclic loadings has been analysed with digital simulation. The fatigue fracture plane position has been determined with mean values of the direction cosines of principal stress axes. Averaging has been done at angle values with use of weights. Eleven various weights have been presented and their usability has been analysed on the basis of experimental results obtained by Rotvel, and Nishihara-Kawamoto. The weights with good agre…
Fatigue fracture planes and expected principal stress directions under biaxial variable amplitude loading
2005
Fatigue behaviour under multiaxial variable amplitude loading can be examined by applying the failure criteria based on the critical plane approach. Positions of the critical plane can be determined in relation to the principal stress or strain directions. In the present paper, the expected directions of the principal stresses under proportional and non-proportional loading have been obtained by averaging the instantaneous values of the Euler angles through special weight functions. The known weight functions based on stress parameters appear not to be efficient for each loading or material being analysed. Thus, the authors consider new weight functions based on energy parameters. The prese…
FATIGUE FAILURE CRITERIA FOR MATERIALS UNDER RANDOM TRIAXIAL STATE OF STRESS
1984
SUMMARY Five fatigue failure criteria are formulated for a random triaxial state of stress whose components have zero mean values. It is assumed that fatigue failure is determined by the stress and strain components that act on an expected fracture plane. It is shown that in some special cases the proposed failure theories reduce to classical theories applied for sinusoidal stresses.