EFFECT OF DIFFERENT CADMIUM CONTENT ON MODIFICATION OF SILICON EUTECTIC IN Al-12%Si ALLOYS

Abstract

This work is devoted to examine and quantify the expected change in the mechanical properties and microstructure of an Aluminum-Silicon alloy after adding various percentages of cadmium. Two alloys were prepared with adding cadmium (1.5 and 3%wt) to the Al-12%Si base alloy. The new microstructure shows that the addition of (1.5 and3% Cd) resulted in a modification of eutectic Si phase from needle plate form to almost spherical one. The modification in Si eutectic phase could improve the mechanical properties. In specific, the hardness increased from 59 to 69 kgmm2, the tensile strength increased from 121 to 140Mpa and the yield strength increased from 31 to51 Map, while ductility decreased from 13 to 8 %.