Al-Zn-Mg alloys have been extensively used for structural applications in aerospace and transportationindustry due to their excellent mechanical properties. Moreover, the grain refinement of aluminum allolys is the researchfocus these years. In order to refine grain size and enhance the mechanical properties of Al-Zn-Mg alloys, traditionalrefiner Al-5Ti-B and RE were added into the cast alloy. The mechanical behavior of Al7Zn2.4Mg alloys with differentAl-5Ti-B and Al-2Zr-Er addition was investigated using X...