Formation of the surface layer in hypoeutectic Al-alloy high-pressure die castings

Otarawanna, S., Gourlay, C. M., Laukli, H. I. and Dahle, A. K. (2011) Formation of the surface layer in hypoeutectic Al-alloy high-pressure die castings. Materials Chemistry and Physics, 130 1-2: 251-258. doi:10.1016/j.matchemphys.2011.06.035

Author Otarawanna, S.
Gourlay, C. M.
Laukli, H. I.
Dahle, A. K.
Title Formation of the surface layer in hypoeutectic Al-alloy high-pressure die castings
Journal name Materials Chemistry and Physics   Check publisher's open access policy
ISSN 0254-0584
Publication date 2011-10
Sub-type Article (original research)
DOI 10.1016/j.matchemphys.2011.06.035
Volume 130
Issue 1-2
Start page 251
End page 258
Total pages 8
Place of publication Lausanne, Switzerland
Publisher Elsevier
Collection year 2012
Language eng
Formatted abstract
A layer of distinctive microstructure known as the surface layer or the skin is often observed near the casting surface of high-pressure die cast (HPDC) parts. With its different microstructure, the surface layer could influence mechanical performance, corrosion properties and also pressure tightness of the whole cast component. This research aims to develop a better understanding of surface layer formation, which is essential to control the microstructure and therefore properties of HPDC components. In this study, microstructural characterization has been performed on HPDC specimens cast from an HPDCspecific Al alloy for structural applications, AlMg5Si2Mn.Most regions in the samples investigated contain ∼10–30 m globular-rosette primary -Al grains and [Al + Mg2Si] eutectic, while very dendritic primary α-Al grains are also present in the surface layer. The surface layer was observed in the region where the alloy did not directly impinge on the die surface during die filling (the so-called indirect impingement zone). In the region between the surface layer and inner regions (the so-called surface-layer edge), the only primary grain population is the very dendritic grains also observed in the surface layer. The surface layer formation is related to shearing at the interface between two parts of material containing different solid fractions (fs) which can occur either during the die-filling or during the intensification stage.
Keyword Metals
Optical microscopy
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: School of Mechanical & Mining Engineering Publications
Official 2012 Collection
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 6 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 11 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Sun, 13 Nov 2011, 06:02:19 EST by System User on behalf of School of Mechanical and Mining Engineering