The effect of whisker misalignment on the hot compressive deformation behavior of SiCw/6061 Al composites at 500 °C

Abstract

SiC whisker-reinforced 6061 Al composites were prepared by squeeze casting followed extrusion. The effect of whisker misalignment on the hot compressive behavior of the SiCw/6061 Al composites at 500 °C has been investigated by means of scanning electronic microscopy (SEM) and Magiscan-2A image analysis. The experimental results show that the whisker orientation has a significant influence on the whisker behavior including whisker breakage and rotation. The rotation angle and the breakage degree of misaligned whiskers decrease with increasing whisker orientation angle between the whisker axis and the compressive direction, which leads to a reduction in softening effect. Meanwhile, the compressive flow stress of the composites also decreases. In addition, the flow stress value of the composites is rather sensitive to the misaligned angle of whiskers, when the whisker orientation angle is small. It is also found that strain softening appears in titling SiC whisker-reinforced Al composites during hot compression at 500 °C.