THE INTERFACIAL COMPOUNDS AND SEM FRACTOGRAPHY OF SQUEEZE-CAST SICP 6061 AL COMPOSITES/

The effects of the addition of silica binder during preform preparatio n on the development of interfacial compounds in squeeze-cast SiCp/606 1 Al composites (containing silicon carbides with particle sizes of 85 . 30 and 14 mu m) M-ere examined using energy dispersive spectroscopy (EDS) X-ray mapping. scanning electron microscopy (SEM) fractography a nd optical microscopy (OM). Various interfacial compounds, Al2O3, MgO and MgAl2O4 were observed. The effects of the various interfacial comp ounds on the SEM fractography and mechanical properties of the composi tes were investigated and a mechanism was suggested. The micromechanis m of crack initiation, crack propagation and final fracture was discus sed using SEM fractography and OM observations.