Of Trace Elements On Pure Aluminum Grain Refinement Of The Role Of Research

Effect and mechanism of Ce,Bi,Zr on grain refining of pure aluminium has been studied by OM,SEM,EDAX,XRD in this paper. For the purpose of obtaining the optimal experiment effect, the ratio of Ce to Bi and percent of Ce,Bi in the grain refiner and the refining temperature all should be determined exactly. In addition, the effect of the ratio of Ce to Zr on grain refining has been studied. The results showed that optimal effect of grain refining can be obtained when the ratio of Ce to Bi was 1:4 or 3:2 because much compound particles BiCe formed in the matrix under this condition. The best content of addition of Ce and Bi was 0.5% and the optimal refining temperature was about 790℃. The effect of grain refining became much better with the addition of Ce increasing when Zr is at a certain content. The best effect of grain refining can be achieved when the content of Zr and Ce were 0.15% and 0.3% respectively. The reason is that much Al₃Zr particles formed which have a function of nucleation. The study of effect and mechanism of Ce,Bi,Zr on grain refining of pure aluminium can become the important reference to the further study of grain refiner for aluminium or novel aluminium alloys.