A356 aluminum alloys with different amount of Sc and Y were prepared.Through metallographic analysis and tensile testing

influences of trace Sc and Y on the properties and microstructure of A356 aluminum alloy were investigated.The results indicate that after compound addition of trace Sc and Y

Al3 Y and Al3 Sc strengthening phase can be generated in the microstructure of A356 aluminum alloy

soα-Al matrix is refined apparently and morphologies of most of eutectoid silicon are transformed from lamellar structure into granulate

which are responsible for improvement of tensile properties and plasticity.With 0.2%Sc+0.2%Y addition

mechanical properties of the alloy exhibit desirable.With excessive Y and Sc addition

the comprehensive performance of the alloy is deteriorated as a result of composition segregation.