An investigation into double oxide film defects in aluminium alloys

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Standard

An investigation into double oxide film defects in aluminium alloys. / Griffiths, W. D.; Caden, A. J.; El-Sayed, M. A.

Materials Science Forum. Vol. 783-786 Trans Tech Publications Inc, 2014. p. 142-147 (Materials Science Forum; Vol. 783-786).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Harvard

Griffiths, WD, Caden, AJ & El-Sayed, MA 2014, An investigation into double oxide film defects in aluminium alloys. in Materials Science Forum. vol. 783-786, Materials Science Forum, vol. 783-786, Trans Tech Publications Inc, pp. 142-147, 8th International Conference on Processing and Manufacturing of Advanced Materials: Processing, Fabrication, Properties, Applications, THERMEC 2013, Las Vegas, NV, United States, 2/12/13. https://doi.org/10.4028/www.scientific.net/MSF.783-786.142

APA

Griffiths, W. D., Caden, A. J., & El-Sayed, M. A. (2014). An investigation into double oxide film defects in aluminium alloys. In Materials Science Forum (Vol. 783-786, pp. 142-147). (Materials Science Forum; Vol. 783-786). Trans Tech Publications Inc. https://doi.org/10.4028/www.scientific.net/MSF.783-786.142

Vancouver

Griffiths WD, Caden AJ, El-Sayed MA. An investigation into double oxide film defects in aluminium alloys. In Materials Science Forum. Vol. 783-786. Trans Tech Publications Inc. 2014. p. 142-147. (Materials Science Forum). https://doi.org/10.4028/www.scientific.net/MSF.783-786.142

Author

Griffiths, W. D. ; Caden, A. J. ; El-Sayed, M. A. / An investigation into double oxide film defects in aluminium alloys. Materials Science Forum. Vol. 783-786 Trans Tech Publications Inc, 2014. pp. 142-147 (Materials Science Forum).

Bibtex

@inproceedings{3043859ae76c47bbab4f23122edffdd2,
title = "An investigation into double oxide film defects in aluminium alloys",
abstract = "When the oxidised surface of a liquid metal is folded over onto itself and entrained double oxide film defects are formed, which form crevices or cracks in the solidified casting, of varying sizes and orientations. These defects not only reduce mechanical properties, but also increase the scatter of properties. This paper reports an analog experiment to study the behavior of the interior atmosphere of double oxide film defects in Al alloy melts of varying Mg content. Air bubbles were trapped in melts of liquid Al alloy which were then solidified after holding for varying periods of time. The composition of the bubbles was subsequently measured using mass spectroscopy. This showed the reaction of oxygen from the bubble atmosphere to form oxides, followed by the consumption of nitrogen to form AlN. Simultaneously, hydrogen from the melt diffused into the air bubble. The changes in composition were used to estimate the rate of change in composition of the interior atmosphere of a typical double oxide film defect of an estimated size. This suggested that double oxide film defects may quickly achieve an interior atmosphere that would consist of a mixture of mainly nitrogen and hydrogen, and that this atmosphere could exist for periods of time greater than the typical solidification times of light alloy castings. In other words, oxide film defects created during mould filling should persist into the solidified casting. In addition, SEM analysis of oxide film defects also suggested the presence of oxide whiskers, which seem to have formed during holding in the melt.",
keywords = "Aluminium alloys, Bifilms, Casting, Double oxide film defects",
author = "Griffiths, {W. D.} and Caden, {A. J.} and El-Sayed, {M. A.}",
year = "2014",
doi = "10.4028/www.scientific.net/MSF.783-786.142",
language = "English",
isbn = "9783038350736",
volume = "783-786",
series = "Materials Science Forum",
publisher = "Trans Tech Publications Inc",
pages = "142--147",
booktitle = "Materials Science Forum",
address = "Germany",
note = "8th International Conference on Processing and Manufacturing of Advanced Materials: Processing, Fabrication, Properties, Applications, THERMEC 2013 ; Conference date: 02-12-2013 Through 06-12-2013",

}

RIS

TY - GEN

T1 - An investigation into double oxide film defects in aluminium alloys

AU - Griffiths, W. D.

AU - Caden, A. J.

AU - El-Sayed, M. A.

PY - 2014

Y1 - 2014

N2 - When the oxidised surface of a liquid metal is folded over onto itself and entrained double oxide film defects are formed, which form crevices or cracks in the solidified casting, of varying sizes and orientations. These defects not only reduce mechanical properties, but also increase the scatter of properties. This paper reports an analog experiment to study the behavior of the interior atmosphere of double oxide film defects in Al alloy melts of varying Mg content. Air bubbles were trapped in melts of liquid Al alloy which were then solidified after holding for varying periods of time. The composition of the bubbles was subsequently measured using mass spectroscopy. This showed the reaction of oxygen from the bubble atmosphere to form oxides, followed by the consumption of nitrogen to form AlN. Simultaneously, hydrogen from the melt diffused into the air bubble. The changes in composition were used to estimate the rate of change in composition of the interior atmosphere of a typical double oxide film defect of an estimated size. This suggested that double oxide film defects may quickly achieve an interior atmosphere that would consist of a mixture of mainly nitrogen and hydrogen, and that this atmosphere could exist for periods of time greater than the typical solidification times of light alloy castings. In other words, oxide film defects created during mould filling should persist into the solidified casting. In addition, SEM analysis of oxide film defects also suggested the presence of oxide whiskers, which seem to have formed during holding in the melt.

AB - When the oxidised surface of a liquid metal is folded over onto itself and entrained double oxide film defects are formed, which form crevices or cracks in the solidified casting, of varying sizes and orientations. These defects not only reduce mechanical properties, but also increase the scatter of properties. This paper reports an analog experiment to study the behavior of the interior atmosphere of double oxide film defects in Al alloy melts of varying Mg content. Air bubbles were trapped in melts of liquid Al alloy which were then solidified after holding for varying periods of time. The composition of the bubbles was subsequently measured using mass spectroscopy. This showed the reaction of oxygen from the bubble atmosphere to form oxides, followed by the consumption of nitrogen to form AlN. Simultaneously, hydrogen from the melt diffused into the air bubble. The changes in composition were used to estimate the rate of change in composition of the interior atmosphere of a typical double oxide film defect of an estimated size. This suggested that double oxide film defects may quickly achieve an interior atmosphere that would consist of a mixture of mainly nitrogen and hydrogen, and that this atmosphere could exist for periods of time greater than the typical solidification times of light alloy castings. In other words, oxide film defects created during mould filling should persist into the solidified casting. In addition, SEM analysis of oxide film defects also suggested the presence of oxide whiskers, which seem to have formed during holding in the melt.

KW - Aluminium alloys

KW - Bifilms

KW - Casting

KW - Double oxide film defects

UR - http://www.scopus.com/inward/record.url?scp=84904546326&partnerID=8YFLogxK

U2 - 10.4028/www.scientific.net/MSF.783-786.142

DO - 10.4028/www.scientific.net/MSF.783-786.142

M3 - Conference contribution

AN - SCOPUS:84904546326

SN - 9783038350736

VL - 783-786

T3 - Materials Science Forum

SP - 142

EP - 147

BT - Materials Science Forum

PB - Trans Tech Publications Inc

T2 - 8th International Conference on Processing and Manufacturing of Advanced Materials: Processing, Fabrication, Properties, Applications, THERMEC 2013

Y2 - 2 December 2013 through 6 December 2013

ER -