The interfacial microstructure and tensile properties of the squeeze cast S
iCw/AZ91 Mg composites were characterized. There exist uniform, fine and di
screte MgO particles at the interface between SiC whisker and magnesium in
the composites using acid aluminum phosphate binder. The interfacial reacti
on products MgO are beneficial to interfacial bonding between SiCw and the
Mg matrix, resulting in an improvement of the mechanical properties of the
composite.