Effect of recrystallisation temperature on texture and grain size of Al-SiC composite

The effect of recrystallisation temperature (250–510°C) on texture and grain size has been studied for 90% cold rolled Al reinforced with 2 vol.-%SiC whiskers. The average grain sizes and grain size distributions were determined using optical microscopy. The crystallographic textures were measured by neutron diffraction and analysed in terms of orientation distribution functions. In addition, the electron back scattering technique was used for a simultaneous determination of grain size and crystallographic orientation. It was found that annealing temperature has a large effect on both texture and grain size. An increase of annealing temperature results in a reduction of recrystallised grain size due to an increase of the number density of recrystallisation nuclei. This effect seems to cease at ∼375°C. The recrystallisation texture is characterised by a rotated cube component ({100}〈013〉) and the strength of this component increases with increasing temperature. This change is explained in terms of the effects of temperature and crystallographic orientation on nucleation and growth.