Effect of Sr addition on an Al–7Si–10 vol.% SiCp cast composites

The effect of additions of Sr (in the range 0.05–0.5%) on the microstructural characteristics of Al–7 wt.% Si–10 vol.% SiCp composites have been studied. Optical microscopy (OM), SEM, EDS, WDS microanalysis techniques and X-ray diffraction powder techniques have been used for the characterization of the composites. It was found that Sr concentrations between 0.05 and 0.20 facilitates incorporation of higher volume fraction of SiC particles and also does not contribute to the overall modification of the matrix. However, at higher wt.% of Sr, Sr-rich compounds were found. These Strontium rich compounds were located at the matrix–ceramic interface.