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Thread 187/34
Aluminium and zinc alloy
2002
Sir,
Please inform what will be the benefit or loss if 10% Zinc is added to Aluminium for die casting, e.g., on it's colour, surface finish, defects, corrosion resistance, etc.
Thanks and regards,
- Moradabad, UP, India
publicly reply to Ashish Vacher
2002
Do you mean a) 90% Al-10% Zn alloy or b) the addition of 10% Zn to an existing alloy? You can begin by checking the phase equilibria for feasibility of casting, but for further data, visit specialized websites such as those given below.
Composition a) would be problemsome due to segregation during the solidification and the high vapor pressure of Zn some 200+ C above its melting point. Compare the Al-Zn phase diagram (http://klara.met.kth.se/pd/element/Al-Zn.html) with that of the Al-Si diagram (http://klara.met.kth.se/pd/element/Al-Si.html). Cooling an Al-10%Zn liquid will result in an Al-rich solid and a Zn-enriched liquid, possibly resulting in Zn vapor bubbles and hence porosity. The final liquid temperature and composition would be a function of cooling rate. The Al-10%Si composition, near that of many commercial diecast alloys, is near a eutectic point, allowing a lower liquid temperature and assuring a fairly constant liquid composition during solidification.
Composition(s) b). Consider funding some research at the Advanced Casting Research Center at Worcester Polytechnic Institute. �Recent research on the interactions between alloy chemistry, microstructure and performance in die-casting alloys was funded by a $500,000 grant from the Department of Energy and overseen by the Cast Metal Coalition and the North American Die Casting Association (NADCA). The work culminated in the book Microstructures and Properties of Aluminum Die Casting Alloys, published by NADCA.� [at least buy the book!]
They have a current research project "Development of an Electronic Data Base for Rapid Selection of Aluminum Die Casting Alloys" with the goals of predicting alloy chemistry required for given properties and the converse of predicting properties for a given alloy.
(http://www.wpi.edu/Academics/Research/ACRC/Research/database.html)
Also, The North American Die Casting Association
(http://www.diecasting.org/) has useful and interesting information on their website, e.g., alloy compositions and �A Study in Aluminum Die Casting Design Electronics Housing for the F/A18.
- Goleta, California

Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
publicly reply to Ken Vlach
ALUMINIUM ALLOY 3003. What would happen if I where to add 1.5% Zinc in this alloy.Especially in the context of producing flat sheet for food containers.
NASH SinghPROD MANAGER - Durban,South africa
2007
publicly reply to NASH Singh
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