Abstract
Fabrication condition of compo-casting process on aluminum borate (Al_<18>B_4O_<33>) reinforced AZ91D (Mg-9%Al-1%Zn) magnesium alloy composites affect to the mechanical properties and microstructure. In this study, the effect of the fraction of solid phase (0-33%fs), the kind of reinforcement (whisker or particle) and casting process (Rheo or Thixo casting) were investigated. In melt casting condition (0%fs), the composite has fine structure with no pores but has coalescence of the reinforcements. The reinforcements in composites fabricated under the semi-solid condition were swept up to post liquid phase and distributed uniformly in this fabricated under the 33%fs condition, the whisker reinforcement or Thixo casting. The composite fabricated by Thixo casting has low strength because of many pores.
