Examination of the Eutectic Modifying Effect of Sr on an Al-Si-Mg-Cu Alloy Using Various Technological Parameters

• Autorzy: Vincze F. , Tokár M. , Fegyverneki G. , Gyarmati G.

Identyfikatory

DOI

10.24425/afe.2020.133334

• Języki publikacji: EN

Abstrakty

EN

With the aid of eutectic modification treatment, the precipitation of coarse lamellar eutectic silicon can be suspended during the solidification of aluminum-silicon alloys, thereby the formation of fine-grained, fibrous eutectic Si can be promoted by the addition of small amounts of modifying elements, such as Sr, to the liquid alloy. The effectiveness of this technique is, however, highly dependent on many technological factors, and the degree of modification can be lowered during the various stages of melt preparation due to the oxidation of the Sr-content of the melt. During our research, we investigated the effect of rotary degassing melt treatments coupled with the addition of three different fluxes on the degree of modification of an Al-Si-Mg-Cu casting alloy. It was also studied, that whether additional Sr alloying made before and during the melt treatments can compensate the Sr fading with time. The degree of eutectic modification was characterized by thermal analysis (TA) and the microscopic investigation of TA specimens. It was found, that by using one of the three fluxes, and by adding Sr master alloy rods before the melt treatments, better modification levels could be achieved. It was also found that the measurement of Sr-concentration by optical emission spectroscopy alone cannot be used for controlling the level of eutectic modification.

Słowa kluczowe

EN

aluminum alloy; solidification process; strontium; modification; thermal analysis

PL

stop aluminium; krzepnięcie; stront; modyfikacja; analiza termiczna

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2020
• Tom: Vol. 20, iss. 3
• Strony: 79--84
• Opis fizyczny: Bibliogr. 26 poz., fot., rys., tab.

Twórcy

autor

Vincze F.

• University of Miskolc, Faculty of Materials Science and Engineering, Miskolc-Egyetemváros, Hungary

autor

Tokár M.

• University of Miskolc, Faculty of Materials Science and Engineering, Miskolc-Egyetemváros, Hungary

autor

Fegyverneki G.

• University of Miskolc, Faculty of Materials Science and Engineering, Miskolc-Egyetemváros, Hungary

autor

Gyarmati G.

• University of Miskolc, Faculty of Materials Science and Engineering, Miskolc-Egyetemváros, Hungary

Bibliografia

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Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020)