CORRELATION OF HARDNESS AND SILICON MORPHOLOGY FOR Al-Si-Sb ALLOY
Orhan Uzun, Fikret Yilmaz, Semra Ergen, Ugur Kolemen, Cem Emeksiz
article (Uluslararası, Hakemli) | Yazar(lar): Orhan Uzun, Fikret Yilmaz, Semra Ergen, Ugur Kolemen, Cem Emeksiz | Yıl: 2018 | Dergi/Kurum: ARCHIVES OF METALLURGY AND MATERIALS | İndeks: WOS.SCI | DOI: 10.24425/118963 | Anahtar Kelimeler: Al-Si alloy, casting, Vickers, finite element analysis — Özet: In this study, we h
In this study, we have focused on the role of silicon morphology on the hardness of eutectic Al - 12 wt.% Si - 0.5 wt.% Sb alloy solidified at different cooling rates. The alloys were produced by using induction melting, arc-remelting and melt-spinning techniques. The cooling rates of the alloys were determined as 0.5, 60 and similar to 10(5)degrees C.s(-1) for induction-melted, arc-remelted and melt-spun alloy. The experimental results show that as the cooling rate increased the coarse silicon phase was substantially refined and its morphology altered from sharp need-like to round shape. Two exothermic peaks, attributed to precipitation and coarsening of silicon from supersaturated alpha-Al, were observed in the DSC curve of MS alloy. Vicker's hardness of melt-spun alloy was found two times higher than those of IMed and ARed alloys. The lowest hardness of induction-melted alloy was ascribed to the lamellar morphology of silicon, yielding decohesive rupture. This result was confirmed by finite element analyzing.