Al-7.2Zn-2.2Mg-1.8Cu alloy melt was prepared by flux protection melting

and the segregation distribution in solidified structure of the alloy by direct squeeze casting was investigated.The results reveal that there exists serious macroscopic and microscopic segregation in the solidified structure

finally the solute elements enriched in liquid phase in the center of the castings can form macro abnormal segregation under pressure.The composition difference between inner dendrites and intergranular eutectic phase is responsible for micro-segregation

and the solidification rate can be increased significantly under the squeeze casting condition

which can reduce the degree of micro-segregation.