Observation of Hot Tearing in Sr-B Modified A356 Alloy

• Autorzy: Uludağ M. , Çetin R. , Dışpınar D.

Identyfikatory

DOI

10.1515/afe-2017-0151

• Języki publikacji: EN

Abstrakty

EN

In this work, T-shaped mould design was used to generate hot spot and the effect of Sr and B on the hot tearing susceptibility of A356 was investigated. The die temperature was kept at 250ºC and the pouring was carried out at 740ºC. The amonut of Sr and B additions were 30 and 10 ppm, respectively. One of the most important defects that may exist in cast aluminium is the presence of bifilms. Bifilms can form by the surface turbulence of liquid metal. During such an action, two unbonded surfaces of oxides fold over each other which act as a crack. Therefore, this defect cause many problems in the cast part. In this work, it was found that bifilms have significant effect over the hot tearing of A356 alloy. When the alloy solidifies directionally, the structure consists of elongated dendritic structure. In the absence of equiaxed dendrites, the growing tips of the dendrites pushed the bifilms to open up and unravel. Thus, leading to enlarged surface of oxide to become more harmful. In this case, it was found that these bifilms initiate hot tearing.

Słowa kluczowe

EN

A356 alloy; casting technology; melt quality; grain refinement; hot tearing

PL

stop A356; technologia odlewania; jakość topienia; rozdrobnienie ziarna; pękanie na gorąco

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2017
• Tom: Vol. 17, iss. 4
• Strony: 165--168
• Opis fizyczny: Bibliogr. 20 poz., rys., tab.

Twórcy

autor

Uludağ M.

• Bursa Technical University, Metallurgical and Materials Eng. Dept., Bursa-Turkey

autor

Çetin R.

• Karatay University, Materials Engineering, Konya-Turkey

autor

Dışpınar D.

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