Microstructures and Mechanical Properties of AI-Fe Alloys Prepared by Semi-Solid Formation

摘要

The effect of alloying element. electromagnetic stirring. reheating and semi-solid formation on thernmicrostructures of Al-Fe alloys was determined. and the mechanical properties of the alloys prepared by semi-solid formationrnat room temperature and high temperature were investigated. The results show that the shape and growth mode of iron-richrnphase in Al-Fe alloys has been changed by adding alloying elements and electromagnetic stirring. which can effectivelyrnrefine primary Al_3Fe phase. The Al_3Fe phases becomes a thin short rod-like from a thick needle-like. and the dendritic grainsrnalmost disappear. The Al_3Fe phase can be refined through dissolving or fusing during reheating. At the higher reheatingrntemperatures. the phenomenon of dissolving and fusing is more remarkable. The Al_3Fe phase will get further refined due tornthe mechanical crushing of semi-solid formation. The larger the extrusion ratio of semi-solid formation. the more remarkablernthe crushing effect and the more uniform the distribution of Al_3Fe phase. The Al-Fe alloys prepared by semi-solid formationrnexhibit high mechanical properties. and have the potential engineering application at the operating temperature of aboutrn500K.