The Study of Micro-segregation in Al-Cu Alloys Using Thermal Analysis and Numerical Modeling

مهندسی متالورژی و مواد

Article 6, Volume 28, Issue 1 - Serial Number 15, March 2017, Pages 51-72   

Document Type: Original Articles

DOI: 10.22067/ma.v28i1.33513

Authors

Mohammad Hasan Avazkonandeh Gharavol¹; Mohsen Haddad Sbzevar^{* 2}

¹Hakim Sabzevari University, Sabzevar, Iran

²Ferdowsi University of Mashhad, Mashhad, Iran

Abstract

The micro-segregation in binary Al-Cu alloys containing 2.2, 3.7, and 4.8 wt.% copper was investigated by differential thermal analysis (DTA) and numerical modeling. For this purpose, the alloys were melted using a DTA furnace with the capability of quenching samples during solidification. The melted samples were cooled at 0.008 and 0.083 K/s and subsequently quenched from predetermined temperatures during cooling. The evolution of the microstructure and micro-segregation was modeled with and without considering excess vacancies formed during solidification. It was found that the experimental and modeling results show a better correlation when excess vacancies are considered

Keywords

Al-Cu Binary Alloys; Micro-Segregation; Thermal Analysis; Excess Vacancy

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