Cu Elements Segregation During Semi-solid Forming Process And Properties Of Al-Fe-Cu Alloy

As the phenomena of forced convection in melt during semi-solid forming process, theCu elements segregation will be appeared in the alloy during solidification, Fe element in thealloy may also have an impact for this segregation. Analyzes the causes of this phenomenonand regularity is important to understand the behavior of Cu element distribution inaluminum alloy during semi-solid forming process, as well as to have theoreticalsignificance and practical value for preparation of alloys, heat treatment process anddevelopment new technology of semi-solid forming.In this paper, the influence of semi-solid blank preparation, reheating remelting andthixoformation technology on Cu elements segregation in Al-5Fe-4Cu alloy has been studied,and the relationship between heat treatment technology and alloy properties has beenresearched. Cu elements segregation laws during semi-solid blank preparation and reheatingremelting stage has been won, as well as the suitable heat treatment technology forstrengthening. Experiments used different electromagnetic stirring current and the reheatingparameters such as temperature, the relationship between technical factors and segregation ofCu element analyzed for providing guidance for semi-solid forming technology; withorthogonal test analysis of aging heat treatment parameters effect on the alloy properties, inorder to achieve the optimization of heat treatment technology.Not plus electromagnetic stirring current experiment results showed that, Cu elements incrystal territories at occurred partial poly, and partial poly is obviously; imposed differentelectromagnetic stirring strength experiment showed that, electromagnetic stirring conduciveto improved Cu elements of partial poly phenomenon, when stirring current respectively for40A, and60A, and80A and100A, stirring current more big, improved Cu elementssegregation in semi-solid blank preparation stage more obviously. reheating remeltexperiment showed that, in respectively used650℃,660℃,670℃and680℃for reheatingexperiment, Cu elements in remlet district tends to uniform distribution, and heatingtemperature more high, remlet district more big, Cu elements distribution more uniform;after thixoformation the phenomenon of Cu elements segregation appeared in rich Fe phasesurface; alloy heat treatment orthogonal experiment results showed that, when heat treatmenttechnology for520℃solid dissolved10h then for175℃of4H artificial aging, thehardness of the alloy will appear the highest value.