Document Type : Original Research Paper

Authors

1 Faculty of Materials and Metallurgy Engineering, Iran University of Science and Technology,Tehran,Iran

2 Faculty of Materials and Metallurgy Engineering, Iran University of Science and Technology, Tehran, Iran

Abstract

Eutectic Silicon phases form as the coarse and acicular shape in Aluminum-Silicon alloys. These phases have detrimental effect on mechanical properties of casting parts. Modification process has been used to change the shape of these phases to fibrous morphology. In this research different level of strontium; in the form of Al-10%Sr master alloy; have been added to 319 aluminum alloy to investigate their effects on modification. Thermal Analysis has been used as a technique to study the cooling curves and first derivative curves. Effect of strontium on solidification parameters such as nucleation temperature ((, and growth temperature () of eutectic silicon has been determined. ((and () have been reduced by increasing strontium content. () can be used as a parameter to control the modification of eutectic silicon. The results of this research indicate that thermal analysis technique can be used as an accurate and quick device of on-line quality control in production lines of aluminum casting industries.

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Main Subjects

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