Schubspannungsbomben in Faserverbunden

Shear Bombs in Fibre Composites Despite an optimum external shape non‐load adapted internal fibre orientation can lead to the formation of shear cracks where crossing tension‐compression principal stress trajectories create localized shear peaks. Trees are subject to those failure because they cannot re‐arrange their fibres after wood formation. Bones can adjust their micro‐structure to changing load conditions and in this way can better control shear failure. The engineer working with fibre composites should be alert to avoid fibre arrangements not following the force flow. Localized shear zones may also form near notches similar to normal notch stresses, however they are not always situated at the contour line of the notch.     

The effects of slant angle on local stress distribution around cooling hole in nickel‐based single crystal

Based on crystal plasticity theory, plate specimens with a cooling hole were adopted to investigate the stress distribution and crystallographic slip characteristics, the effects of crystallographic orientations taken into consideration. The slant angles are 0°, 15°, 30° and 45°. The results show that severe stress concentrations and high stress gradients present at the cooling holes. Stress distribution changes significantly with different slant angles and crystallographic orientations. Slip bands advancing to specific directions initiate around the holes and the characteristics of the slip band vary with slant angles. Four apparent maximum values occur along the hole in the three orientations and the locations of the maximum values are much dependent on the slant angles. The influences of slant angle on the activating law of the slip systems are remarkable.