Associate professor, Cairo UniversityRensselaer Polytechnic Institute, GizaTroy, NY
Pages: 15 Published: Jan 1991
The work of Dvorak et al. and Bahei-El-Din et al. on fracture of unidirectionally reinforced boron/aluminum specimens with a center notch is extended here for specimens with other types of discontinuities. The experimental results indicate that long, discrete plastic shear zones similar to those found at the notch tip are present in all specimens. The plastic zones grow from the discontinuity in the fiber direction. The measured fracture strength was not affected by geometry of the notch, it is only a function of the notch width/specimen width ratio. Finite element analysis of the specimens with center square hole provided the plastic zone length and the local stresses. The results verified that the criterion controlling fracture in center-notched specimens is applicable to other notch geometries. Namely, failure is controlled by a critical ratio of the largest principal stress to off-axis unnotched strength in the principal direction, in a small representative volume in the vicinity of the notch.
composite materials, fracture, notches, holes, plastic zone, fracture criterion, experiments, finite element analysis, fatigue (materials)
Paper ID: STP17744S