Al-9Si-0.2Mg-xFe alloys with different Fe content were prepared by gravity casting

and the effects of Fe element on the microstructures

thermal conductivity and mechanical properties of Al alloys were investigated through OM

SEM and EDS analysis.The results indicate that with Fe increasing from 0.1% to 1.0%

the morphology of iron-containing intermetallic is converted from script likeπphase to needle likeβphase

and the dimension is increased from several microns to larger than 100μm.Correspondingly

the thermal conductivity

tensile strength and elongation of alloys are decreased by 6%

11.7% and 66%

respectively

and a sharper decrease occurs when the Fe content is over 0.6%.