Local strain contours around inclusions in wire-drawn composites

Abstract Composite samples are produced by casting copper around a long, single-fibre inclusion of tungsten. Samples are subsequently wire-drawn to reduce the grain size. Using high energy X-ray diffraction, the spatial distribution of residual lattice strains is mapped, showing large strain gradients between the sample surface and fibre matrix interface in samples with different thermal histories. The large strain gradients are primarily attributed to inhomogeneous deformation caused by the presence of the fibre during drawing. Distinct non-linearities in the strain gradients are attributed to the development of strong radial texture variations, and annealing at 300°C is found to significantly reduce the magnitude of the strain gradients.