Effect of Modification and Cooling Rate on Primary Grain in Al-Cu Alloy

• Autorzy: Górny M. , Sikora G.
• Języki publikacji: EN

Abstrakty

EN

This paper presents a study of the effect of the modification and coolingrate on the grain countα(Al) in the Al-5Cu alloy. Research was performed on castings with walls thickness between 3 mm and 25 mm. Cooling curves were recorded to determine the cooling rate and the degree of undercooling at the beginning of solidification. It has been shown that cooling rate increases exponentially as the wall thickness of casting decreases. Moreover it has been demonstrated that the cooling rate of castings changes within a wide range (21ºC/s - 1ºC/s) when the wall thickness changes from 3 up to 25 mm. Metallographic examinations revealed primary grains (primary α(Al) grains).The paper show that the relationship between the grain count and the degree of undercooling (for non-modified and modified alloys) can be represented by the equation N = Nv = np·exp(-b/_Tα), based on the Weibull's distribution of the size of nucleation sites.

Słowa kluczowe

EN

modification; cooling rate; aluminium alloys; grain refinement

PL

modyfikacja; szybkość chłodzenia; stopy aluminium; rozdrobnienie ziarna

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2014
• Tom: Vol. 14, iss. 3
• Strony: 21--24
• Opis fizyczny: Bibliogr. 12 poz., rys., wykr.

Twórcy

autor

Górny M.

• AGH University of Science and Technology, Faculty of Foundry Engineering, Department of Engineering of Cast Alloys and Composites, Reymonta 23, 30-059 Kraków, Poland

autor

Sikora G.

• AGH University of Science and Technology, Faculty of Foundry Engineering, Department of Engineering of Cast Alloys and Composites, Reymonta 23, 30-059 Kraków, Poland

Bibliografia

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