Effect of Cooling Rate and Copper Content on the Non-Equilibrium Eutectic Formation in Binary Al-Cu Alloys by Computer- Aided Cooling Curve Method

Subject Areas :

Mehdi  Dehnavi ¹ (کارشناسی ارشد، گروه مهندسی متالورژی و مواد، دانشگاه فردوسی مشهد)
Mohsen  Haddad Sabzevar ² (استاد، گروه مهندسی متالورژی و مواد، دانشگاه فردوسی مشهد، مشهد)

Received: 2016-09-13 Accepted : 2016-09-13 Published : 2016-08-22

Keywords: Cooling curve, Latent heat, First Derivative Curve, Non- Equilibrium Eutectic,

Abstract :

In this study, the effect of cooling rate and copper addition was taken into consideration in non- equilibrium eutectic transformation of binary Al-Cu melt via cooling curve analysis.  For this purpose, melts with different copper weight percent of 2.2, 3.7 and 4.8 were prepared and cooled in controlled rates of 0.04 and 0.42 °C/sec. Results show that, latent heat of alloy highly depends upon the post- solidification cooling rate and composition. As copper content of alloy and cooling rate increase, achieved non- equilibrium eutectic phase increases that leads to release of much latent heat and appearing of second deviation in cooling curve. This deviation can be seen in first time derivative curve in the form of a definite peak.

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