Boron/aluminum laminates in symmetric layups of [±45] and [±45/02] containing discontinuities in the form of holes and slits were tested in tension. Both layups exhibited decreases in failure stress with discontinuity size. However the two exhibited quite different failure modes. The [±45 ] failed with interlaminar shear as the dominant mode whereas the [±45/02] specimens reacted to discontinuities catastrophically in a manner suggestive of the effect of cracks on homogeneous metals. A correlation is proposed for the fracture of the [±45/02] laminate.
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