Deformation studies of metal matrix composites using electron backscatter patterns

Abstract

Electron backscatter patterns (EBSPs) are known to be degraded by specimen deformation. Quantification of the EBSP diffuseness and its variation with strain was made for the aluminium alloy 6061 using digital image analysis and discrete Fourier methods. The local distribution of matrix deformation was examined in a unidirectional continuous fibre composite which had been failed in transverse tension. Large matrix strains (above 10%) were only found in a region extending approximately 1 fibre radius from the fracture surface. The distribution of matrix dislocations was established qualitatively for a general unit cell of the fibre array. A failed cross-ply laminate with fibres at 0° and 90° to the tensile load axis was also examined. In particular the increased matrix deformation near a break in a 0° fibre was demonstrated.