Failure of centre notched specimens of 6061 aluminium reinforced with unidirectional boron fibres

The fracture of 6061 aluminium alloy reinforced with unidirectional boron fibres has been investigated using a technique based on a critical stress intensity, Kc.Critical stress intensity factors were obtained by substituting the failure stress and the initial crack length into the appropriate expression for Kc. Values were obtained that appeared to depend on the dimensions of the specimens. A model of specimen deformation was developed based on a shear lag analysis which enabled both the extension of the specimens and the fracture stresses to be predicted.