Thermodynamic Assessment of Mushy Zone in Directional Solidification

• Autorzy: Mikołajczak P. , Ratke L.

Identyfikatory

DOI

10.1515/afe-2015-0088

• Języki publikacji: EN

Abstrakty

EN

Solidification of AlSiFe alloys was studied using a directional solidification facility and the CALPHAD technique was applied to calculate phase diagrams and to predict occurring phases. The specimens solidified by electromagnetic stirring showed segregation across, and the measured chemical compositions were transferred into phase diagrams. The ternary phase diagrams presented different solidification paths caused by segregation in each selected specimen. The property diagrams showed modification in the sequence and precipitation temperature of the phases. It is proposed in the study to use thermodynamic calculations with Thermo-Calc which enables us to visualize the mushy zone in directional solidification. 2D maps based on property diagrams show a mushy zone with a liquid channel in the AlSi7Fe1.0 specimen center, where significant mass fraction (33%) of β-Al₅FeSi phases may precipitate before α-Al dendrites form. Otherwise liquid channel occurred almost empty of β in AlSi7Fe0.5 specimen and completely without β in AlSi9Fe0.2. The property diagrams revealed also possible formation of α–Al₈Fe₂Si phases.

Słowa kluczowe

EN

aluminum alloy; directional solidification; mushy zone; CALPHAD technique; Fe intermetallics; β-Al5FeSi

PL

stop aluminium; krzepnięcie kierunkowe; strefa półciekła; technika CALPHAD; β-Al5FeSi

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2015
• Tom: Vol. 15, iss. 4
• Strony: 101--109
• Opis fizyczny: Bibliogr. 16 poz., rys., wykr.

Twórcy

autor

Mikołajczak P.

• Institute of Materials Technology, Poznan University of Technology, Piotrowo 3, 60-965 Poznan, Poland

autor

Ratke L.

• Institut für Werkstoff-Forschung, German Aerospace Center DLR, Linder Höhe, 51147 Köln, Germany

Bibliografia

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