Nano Double Oxide Film (NDOF) Characteristics of A356 Alloy Casting Protected With Beryllium in Turbulence Conditions

Document Type : Original Research Article

Authors

1 M.Sc. Student, School of Metallurgy and Materials Engineering, Iran University of Science and Technology

2 Professor, School of Metallurgy and Materials Engineering, Iran University of Science and Technology

10.22034/frj.2018.135424.1045

Abstract

The effect of beryllium addition (200 ppm and 2000 ppm) on dynamically formed double oxide film of aluminum A356 alloy was ‎investigated. Dynamically double oxide films were obtained by gravity casting in a cup of thin-walled steel at different free ‎fall of melt and solidified under a vacuum of 80 mbar. The melt quality according to the bifilm index for melts containing ‎‎2000 ppm of beryllium for molten free fall height of 200 and 300 mm is 5.6 and 5.20 mm, respectively. Scanning electron ‎microscopy (SEM) images show a change in the morphology and thickness of the young double oxides containing the ‎beryllium element in dynamic conditions. By adding 2000 ppm of beryllium, the thickness of the film is reduced. For ‎amount of 200 ppm, the edges of the oxide screed and its greater thickness are oxide film properties. Reducing the thickness ‎can mean increased flexibility of oxide films composed of melt containing beryllium. Also, the radiographic results of RPT ‎samples showed that the cavities were reduced by adding beryllium.‎

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References

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Founding Research Journal
Volume 2, Issue 2 - Serial Number 5
September 2018
Pages 71-78

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History

  • Receive Date: 14 June 2018
  • Revise Date: 03 October 2018
  • Accept Date: 04 October 2018

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