Hot compressive deformation behaviour of aluminium matrix composites with misaligned SiC whiskers

Abstract

Hot compressive tests of 6061 aluminium alloys reinforced by SiC whiskers with various orientation angles have been conducted at 300 and 500°C. The effects of compressive temperature and whisker orientation on the high temperature deformation behaviour of the SiC_w/Al composites were investigated. The experimental results show that the whisker behaviours during the hot compassion depend greatly on the compressive temperature and the whisker orientation angle between whisker axis and compressive direction. With increasing the deformation temperature the whisker breakage degree decreases, whereas the whisker rotation angle increases. Meanwhile, the rotation angle and breakage degree of the misaligned whiskers decreases with increasing whisker orientation angle. In addition, it was also found that the shape of the stress - strain curve of the composites relates to the compressive temperature and the whisker orientation angle, and the flow stress value of the composites is sensitive to the whisker orientation angle when it is smaller than 30°.