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Journal of Materials Science

, Volume 28, Issue 7, pp 1775–1780 | Cite as

The microstructural control of cast and mechanical properties of zinc-aluminium alloys

  • M. A. Savas
  • S. Altintas
Papers

Abstract

The zinc-aluminium alloys containing 8, 12, and 27% aluminium are finding increasing applications in the casting industry. These alloys are stronger than most aluminium alloys. In addition, they possess high wear resistance and bearing properties. However, surface sinks and shrinkage defects are observed on the bottom faces of such castings, contrary to general foundry practice. In the present investigation, this problem observed in the Zn-8%Al, Zn-12%Al, Zn-27%Al alloys was tackled by controlling various casting parameters and also by additions of the master alloys of strontium and lithium into the molten alloys. It was found that the underside shrinkage problem was influenced by the aluminium content of the alloy, melt superheat, casting size and cooling conditions. The strontium and lithium additions were found to be beneficial in reducing the underside shrinkage problem. The ultimate tensile strength, fracture elongation and Vickers hardness were all increased with aluminium concentration and lithium addition. It was found also that the most problematical Zn-27%Al alloy, which provided the highest mechanical properties, was very suitable for the squeeze-casting technique. The mechanical properties were increased sharply in these squeeze-cast bars.

Keywords

Aluminium Alloy Strontium Wear Resistance Ultimate Tensile Strength Vickers Hardness 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman & Hall 1993

Authors and Affiliations

  • M. A. Savas
    • 1
  • S. Altintas
    • 1
  1. 1.Mechanical Engineering DepartmentBogazici UniversityBebek, IstanbulTurkey

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