Assessment of Mechanism of Pore Formation in Directionally Solidified A356 Alloy

• Autorzy: Uludag M. , Dispinar D.

Identyfikatory

DOI

10.1515/afe-2017-0029

• Języki publikacji: EN

Abstrakty

EN

It is well-known that the better the control of the liquid aluminium allows obtaining of better properties. One of the most important defects that is held responsible for lower properties has been the presence of porosity. Porosity has always been associated with the amount of dissolved hydrogen in the liquid. However, it was shown that hydrogen was not the major source but only a contributor the porosity. The most important defect that causes porosity is the presence of bifilms. These defects are surface entrained mainly due to turbulence and uncontrolled melt transfer. In this work, a cylindrical mould was designed (Ø30 x 300 mm) both from sand and die. Moulds were produced both from sand and die. Water cooled copper chill was placed at the bottom of the mould in order to generate a directional solidification. After the melt was prepared, prior to casting of the DC cast samples, reduced pressure test sample was taken to measure the melt quality (i.e. bifilm index). The cast parts were then sectioned into regions and longitudinal and transverse areas were investigated metallographically. Pore size, shape and distribution was measured by image analysis. The formation of porosity was evaluated by means of bifilm content, size and distribution in A356 alloy.

Słowa kluczowe

EN

directional solidification; porosity; bifilm index; grain refinement; casting

PL

krzepnięcie kierunkowe; porowatość; ziarna; odlewy

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2017
• Tom: Vol. 17, iss. 1
• Strony: 157--162
• Opis fizyczny: Bibliogr. 15 poz., rys., tab., wykr.

Twórcy

autor

Uludag M.

• Faculty of Engineering, Metallurgical and Materials Eng. Dept, Selcuk University, Konya-Turkey

autor

Dispinar D.

• Faculty of Engineering, Metallurgical and Materials Eng. Dept., Istanbul University, Istanbul-Turkey

Bibliografia

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Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).