Assessment of Mechanism of Pore Formation in Directionally Solidified A356 Alloy

Küçük Resim Yok

Tarih

2017

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

DE GRUYTER OPEN LTD

Erişim Hakkı

info:eu-repo/semantics/openAccess

Özet

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 (O30 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.

Açıklama

Anahtar Kelimeler

Directional solidification, Porosity, Bifilm index, Grain refinement, Casting

Kaynak

ARCHIVES OF FOUNDRY ENGINEERING

WoS Q Değeri

N/A

Scopus Q Değeri

Q3

Cilt

17

Sayı

1

Künye