- Tytuł:
- Observation of Hot Tearing in Sr-B Modified A356 Alloy
- Autorzy:
-
Uludağ, M.
Çetin, R.
Dışpınar, D. - Powiązania:
- https://bibliotekanauki.pl/articles/380985.pdf
- Data publikacji:
- 2017
- Wydawca:
- Polska Akademia Nauk. Czytelnia Czasopism PAN
- Tematy:
-
A356 alloy
casting technology
melt quality
grain refinement
hot tearing
stop A356
technologia odlewania
jakość topienia
rozdrobnienie ziarna
pękanie na gorąco - Opis:
- 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.
- Źródło:
-
Archives of Foundry Engineering; 2017, 17, 4; 165-168
1897-3310
2299-2944 - Pojawia się w:
- Archives of Foundry Engineering
- Dostawca treści:
- Biblioteka Nauki