Effects of processing parameters on microstructure and Cu distribution in squeeze casting Al-5Cu-0.4Mn alloy were investigated.The results show that primary α-Al grain size in the alloy is significantly refined with solidification under a pressure of 25 MPa.Coarse microstructure is increased with increasing in pouring temperature.Non-uniform and coarse microstructure is formed with increasing in mould preheating temperature.Normal solute concentration profile can be observed in the squeeze casting alloy rather than inverse segregation under gravity casting Cu content is increased from the edge to the center.That is attributed to solute-rich driven to the inside of the castings through skeleton channel of inter-dendrite by forced feeding of pressure.The average solubility of Cu in α-Al matrix is increased with the increase of applied pressure.Cu content in primary α-Al grain rises with radius distance of the specimen.Sound squeeze castings of Al-5Cu-0.4Mn alloy with fine grain structure and less macro-segregation can be obtained with a pressure of 100MPa

pouring temperature of 680～730 ℃

and die temperature of 200 ℃.