Reference Dies for the Evaluation of Tensile Properties of Gravity Cast Al-Si Alloys: An Overview

Abstract:

Aluminium-Silicon (Al-Si) alloys are the most extensively used Al foundry alloys and are widely used in gravity die-casting (GDC) of automotive components. Reference dies are used to characterize the tensile properties of the castings. Among the various die configurations, the ASTM B-108 (also called the Stahl Mold), and the AA Step Mold are most popular in the foundries. Several modifications to the standard dies have been suggested in the scientific literature to obtain better mechanical properties in minimizing casting defects. This work reviews the scientific literature on the effect of different reference dies on the porosity and tensile properties of the Al alloy castings.

• Periodical: Materials Science Forum (Volumes 794-796)
• Pages: 71-76
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.794-796.71
• Online since: June 2014
• Authors: Anilchandra R. Adamane*, Elena Fiorese, Giulio Timelli, Franco Bonollo, Lars Arnberg
• Keywords: ASTM, Foundry Aluminium Alloys, Gravity Die-Casting, Porosity, Tensile Properties

References

[1] A.M. Gokhale, G.R. Patel, Origins of variability in the fracture-related mechanical properties of a tilt-pour-permanent-mold cast Al-alloy, Scripta Mater. 52 (2005) 237–241.

DOI: 10.1016/j.scriptamat.2004.09.011

[2] M. Tiryakioglu, J. Campbell, N.D. Alexopoulos, On the Ductility of Cast Al-7 Pct Si-Mg Alloys, Metall. Mater. Trans. 40A (2009) 1000-1007.

DOI: 10.1007/s11661-008-9762-4

[3] X. Dai, X. Yang, J. Campbell, J. Wood, Influence of oxide film defects generated in filling on mechanical strength of aluminium alloy castings, Mater. Sci. Tech. 20 (2004) 505-513.

DOI: 10.1179/026708304225012387

[4] J. Runyoro, S.M.A. boutorabi, J. Campbell, Critical gate velocity for film- forming casting alloys: A basis for process specification, AFS Trans. 100 (1992) 225-234.

[5] J. Campbell. Proc. Int. Technology Forum, Stratford-upon-Avon, UK, June 1997, CIATF, 3-18.

[6] J. Campbell, Complete Casting Handbook: Metal Casting Processes, Metallurgy, Techniques and Design. Elsevier, Oxford, UK, (2011).

[7] X. Yang, T. Din, J. Campbell, Liquid metal flow in molds with off-set sprue, Int. J. Cast Metals Res. 11 (1998) 1-12.

DOI: 10.1080/13640461.1998.11819253

[8] X. Yang, M. Jolly, J. Campbell, Limitations of surface turbulence during filling using a vortex-flow runner, Alum. Trans. 2 (1) (2000) 67-80.

[9] B. Sirrel, J. Campbell, Mechanism of filtration in reduction of casting defects due to surface turbulence during mold filling, AFS Transactions., 105 (1997) 645-654.

[10] T.O. Mbuya, M.F. Oduori, G.O. Rading, M.S. Wekesa, Effect of runner design on mechanical properties of permanent mould aluminium castings, Inter. J. Cast Metals Res. 19 (2006) 357- 360.

DOI: 10.1179/136404606x157818

[11] E.W. Miguelucci, The Aluminum Association Cast Alloy Test Program: Interim Report, AFS Trans., 93 (1985) 913–16.

[12] G.K. Singworth, T.A. Kuhn, Use of Standard' Molds to Evaluate Metal Quality and Alloy Properties, AFS Trans. (2009) 55-62.

[13] F. Grosselle, G. Timelli, F. Bonollo, A. Tiziani, E. Della Corte, Correlation between microstructure and mechanical properties of Al-Si cast alloys, la metallurgia italiana 101 (2009) 25–32.

[14] S. Akhtar, G. Timelli, F. Bonollo, L. Arnberg, M. Di Sabatino, A comparative study of defects and mechanical properties in high pressure die cast and gravity die cast aluminium alloys, I. Foundry Res. /Giessereiforschung 61 No. 2 (2009) 2-14.

DOI: 10.3403/30299762u

[15] K.R. Whaler: Stahl Specialty Company, Kingsville, MO, private communication, (2003).

[16] Standard Specification for Aluminum-Alloy Permanent Mold Castings. ASTM standard B 108-12.

[17] D. Emadi, V.V. Whiting, M. Sahoo, P.D. Nwecombe, T.M. Castles, P. Burke, K.D. Callaghan, Effect of Test Bar Mould Design and Heat Treatment Parameters on the Mechanical Properties of Sr-Modified A356. 2 Alloy, AFS Trans. (2001) 487-498.

[18] G. Birsan, P. Ashtari, S. Shankar, Valid mould and process design to cast tensile and fatigue test bars in tilt pour casting process, Inter. J. Cast Metals Res. 24 (2011) 378-384.

DOI: 10.1179/1743133611y.0000000005

[19] D. Emadi, L. Whiting, M. Sahoo, Taking another look at test bar molds, Modern Casting A.F.S. Feb (2005) 32-34.

[20] M. Twilley, ASTM B-108 Aluminum Tensile Bar Mold Redesign, Inter. J. Metalcasting Winter (2012) 57-61.

DOI: 10.1007/bf03355479

[21] Y. Wang, D. Schwam, D.V. Neff, C.J. Chen, X. Zhu, Improvement in Mechanical Properties of A356 Tensile Test Bars Cast in a Permanent Mold by Application of a Knife Ingate, Metall. Mater. Trans. 43A (2012) 1048-1059.

DOI: 10.1007/s11661-011-0918-2