MECHANICAL PROPERTIES OF SQUEEZE INFILTRATED AS52 MAGNESIUM MATRIX COMPOSITES

Aluminum borate whisker (9(Al2O3)·(B2O3)) reinforced AS52(with and without strontium modification) metal matrix composites (MMC) were fabricated by the squeeze infiltration method. Creep rupture test was carried out at 150°C and 100 MPa condition. Results showed that Alborex reinforcement and modified polygonal shape Mg2Si phase contributed to the enhancement of mechanical properties and creep resistance. Creep rupture time was increased 11% and minimum creep rate was decreased 17% in the composite. At the Alborex/matrix interface, uniform thin layer of MgO was formed. The initiation of micro-voids at the reinforcement/matrix or Mg2Si/matrix interface was followed by their growth and coalescence to macro-cracks.