Metallurgical Engineering

Metallurgical Engineering

Study on the effect of first step agetemperature on the mechanical properties and microstructure of Al-Cu-Mg alloy intwo steps aging process

Document Type : Research Paper

Authors
bahman mirzakhani 1
Yousef Payandeh 2
hamed talebi 2
Mohammad Maleki 3
Mohsen Bahrami 4
1 School of Metallurgy and Materials Science, Iran University of Science and Technology
2 Department of Materials Science and Engineering, Arak University, Arak,
3 Department of Materials Science and Engineering, Arak University
4 Research and Development of Techno Arak,
10.22076/me.2018.77964.1165
Abstract
In this research, the effect of first step age temperature during two steps aging process on the strength, ductility, hardness and microstructure of Al-Cu-Mg alloy has been investigated to obtain an optimum combination of strength and ductility. After solution treatment and quenching the samples in the water, they have artificially been aged for 2 hours in 175, 190, 205°C. Then the samples were naturally aged for 10, 50, 100 hours. To investigate the mechanical properties, all the samples were subjected to tensile test and microstructure analysis after each cycle. The data of one and two steps aging treatment and also the effect of first step temperature were compared. The results show that second step of natural aging by affecting the stability of precipitates and microstructure leads to change in tensile properties. With increasing the first step aging temperature, the impact of second step aging process decreases. Also two steps aging process with temperature of 190°C in first step and time of 50 hours in naturally aging results in and optimum combination of strength and ductility.
Keywords
Al-Cu-Mg alloy
two steps aging
tensile properties
Microstructure
 
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  • Receive Date 08 January 2018
  • Revise Date 09 May 2018
  • Accept Date 13 May 2018