RETRACTED ARTICLE: Comparison on grain refinement efficiency of peritectic and eutectic alloying elements on pure aluminium

The work investigated the grain refining efficiency of peritectic forming solutes as well as eutectic solutes on pure Al. Significant grain refinement for peritectic and small refinement for the eutectic elements were achieved and the mechanisms of refinement were studied. In order to investigate the grain structure and solidification phenomena for each set of alloys, a TP-1 test, as well as thermal analysis, was performed and back scattered images were used to analyze the phases that may contribute to the grain refinement. It appears that the significant grain refinement of peritectic elements is due to the formation of in-situ properitectic particles and their appropriate constitutional undercooling. The results suggest that the availability of potent nuclei and exogenous particles play major roles in the grain refinement efficiency. However, in the case of eutectic elements only segregation power contributes to refinement whilst the availability of potent nuclei is of paramount importance.