Che Nor Aiza JAAFAR, Ismail ZAİNOL, Recep ÇALIN

Effects of Heat Treatment on the Hardness Properties and Microstructure of Al-6505 Alloy

The effects of heat treatment on the ageing response, hardness properties and the microstructure development of Al-6505 alloy have been investigated. In order to study these effects, the alloy sample was solution treated at 550°C for 30 minutes and then quenched into cold water at room temperature followed by artificially aged at elevated temperature of 100 oC, 185 oC and 300 oC. The ageing response of Al-6505 alloy was monitored using Vickers hardness test. The distribution of the precipitates formed in Al-6505 alloy was monitored by transmission electron microscopy (TEM). The results showed that time to reach peak hardness and peak hardness values decreased as the ageing temperatures increased. It was found that increasing in hardness values of the alloy were due to needle-shaped precipitates formation during ageing treatment. Prolonged ageing time to over-aged condition resulting in increased the size but reduced the number of precipitates; as a result the hardness of Al-6505 alloy was reduced. The effects of heat treatment on the ageing response, hardness properties and the microstructure development of Al-6505 alloy have been investigated. In order to study these effects, the alloy sample was solution treated at 550°C for 30 minutes and then quenched into cold water at room temperature followed by artificially aged at elevated temperature of 100 oC, 185 oC and 300 oC. The ageing response of Al-6505 alloy was monitored using Vickers hardness test. The distribution of the precipitates formed in Al-6505 alloy was monitored by transmission electron microscopy (TEM). The results showed that time to reach peak hardness and peak hardness values decreased as the ageing temperatures increased. It was found that increasing in hardness values of the alloy were due to needle-shaped precipitates formation during ageing treatment. Prolonged ageing time to over-aged condition resulting in increased the size but reduced the number of precipitates; as a result the hardness of Al-6505 alloy was reduced.

Keywords:

Al 6505, heat treatment, ageing response,

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Aiza Jaafar, C.N., Azmi R., Zuhailawati, H., Ismail Z,. (2011) Effect of Mg, Si and Cu content on the microstructure of dilute 6000 series aluminium alloys, Journal of Alloys and Compounds, 509, 8632– 8640.
Aiza Jaafar, C.N., Ismail Z., Harun, M., Yazid., A.A. (2013). Relationship between the microstructure and property of Al-0.21 wt%Mg-0.41wt%Si alloy, Malaysian Journal of Microscopy, 9, 42-46.
Aiza Jaafar, C.N., Ismail Z., Mohamad Sapri1, M.A.Z. (2015). The Effects of Thermal Ageing on Properties and Microstructure of Al-6063 Alloy, Key Engineering Materials, 694, 111-115.
Emma, S., Salem., S. (2010).The heat treatment pf Al-Si-Cu-Mg casting alloys, Journal of Materials Processing Technology, 210, 249-1259.
Polmear, I.J. (2017). Light Alloys from traditional alloys to nanocrystals. 5th edition, Oxford: Butterworth Heinmann. Zhenguo L., Zhijun Z., Guangwen Z., Pizhi Z., Warren J. P. (2021). The effect of Mg and Si content on the microstructure, texture and bendability of Al-Mg-Si alloys Materials Science & Engineering A, 814.