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Journal of Materials Science

, Volume 30, Issue 6, pp 1584–1594 | Cite as

Strontium modification of aluminium alloy castings in the expendable pattern casting process

  • L. Wang
  • S. Shivkumar
Papers

Abstract

The influence of strontium modification on microstructure, pore characteristics and tensile properties of Al-Si-Cu castings produced by the expendable pattern casting (EPC) process has been investigated. Test castings have been produced at strontium concentrations varying from 0.0004%–0.03%. The castings have been analysed by microscopic and image analysis techniques. The results indicate that optimum strontium concentrations are between 0.01% and 0.015%. A coarsening of silicon particles is observed at strontium concentrations greater than 0.015%–0.02%. The addition of strontium to the melt also refines the iron- and copper-bearing phases in the casting. The amount of bulk porosity, average pore size and tensile properties of modified EPC castings are comparable to green sand castings. EPC castings are prone to surface porosity. Strontium modification has a significant effect on the pore distributions in EPC castings. The overall porosity and the maximum pore size increase with strontium modification.

Keywords

Strontium Tensile Property Average Pore Size Silicon Particle Pore Characteristic 
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 1995

Authors and Affiliations

  • L. Wang
    • 1
  • S. Shivkumar
    • 1
  1. 1.Department of Mechanical EngineeringWorcester Polytechnic InstituteWorcesterUSA

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