Influence of Solution Heat Treatment Temperature and Time on the Microstructure and Mechanical Properties of Gas Induced Semi-Solid (GISS) 6061 Aluminum Alloy

Abstract:

The influence of solution heat treatment (SHT) temperature and time on the microstructure and mechanical properties of semi-solid 6061 aluminum alloy has been investigated in this study. Microstructure of the as-cast 6061 aluminum alloy mainly consisted of globular α-Al matrix and eutectic phase (α-Al + Mg₂Si) at the grain boundary (GB). Iron rich intermetallic phase was also observed at the grain boundary. Eutectic phase started to dissolve after solution heat treatment. The dissolution of eutectic phase increased with increasing solution treatment time, however, the amount of remaining eutectic phase was found to be slightly changed after solution treating longer than 1 h at 550 °C and 2 h at 530 °C. Hardness and tensile results of specimens after artificial aging were utilized to compare and select the optimum solution heat treatment condition cooperating with the microstructural observation. The optimum solution heat treatment condition of the alloy in this study was at 530 °C for 2 h.

• Periodical: Applied Mechanics and Materials (Volumes 313-314)
• Pages: 67-71
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.313-314.67
• Online since: March 2013
• Authors: Nitikarn Pajaroen, Thawatchai Plookphol, Jessada Wannasin, Sirikul Wisutmethangoon
• Keywords: AA6061 Aluminum Alloy, Gas Induced Semi-Solid (GISS) Process, Solution Heat Treatment

References

[1] C.Y. Chou, S.L. Lee and J.C. Lin: Mater. Sci. Eng. A 485 (2008), pp.461-467.

[2] H. Demir and S. Gündüz: Mater. Design 30 (2009), pp.1480-1483.

[3] T. Oppenheim, O.R. Clark and W.E. Frazier: Engineering Failure Analysis Vol. 14 (2007), pp.218-225.

[4] K. Dehghani, M. Salehi, M. Salehi and H. Aboutalebi: Mater. Sci. Eng. A 489 (2008), pp.245-252.

[5] F.Ozturk, A. Sisman, S.Toros, S. Kilic and R.C. Picu: Mater. Design 31 (2010), pp.972-975.

DOI: 10.1016/j.matdes.2009.08.017

[6] T.V. Rajan, C.P. Sharma and A. Sharma, in: Heat Treatment: Principles and Techniques, Prentice-Hall of India Private Limited, New Delhi (2003), pp.321-339.

[7] J.R. Davis, in: ASM Specialty Handbook: Aluminum and Aluminum alloys, Mater. Inf. Soc. (1993).

[8] R.P. Garrett, J. Lin and T.A. Dean: Int. J. Plast. 21 (2005), pp.1640-1657.

[9] W.F. Smith, in: Structure and Properties of Engineering Alloys: Aluminium Alloy (1993), pp.203-209.

[10] J. Wannasin, S. Janudom, T. Rattanochaikul, R. Canyook, R. Burapa, T. Chucheep and S.Thanabumrungkul: Trans. Nonferrous. Met. Soc. 20 (2010), p. s1010-s1015.

DOI: 10.1016/s1003-6326(10)60622-x

[11] Y. L. Liu, S.B. Kang and H.W. Kim: Mater. Letters. 41 (1999), pp.267-272.

[12] J. Zander and R. Sandström: Mater. Design 29 (2008), pp.1540-1548.

[13] L. Wang and X.Y. Q, in: Scripta Mater. 49 (2003), pp.243-248.

[14] E. Tan and B. Ögel: Turkish J. Eng. Env. Sci. 31 (2007), pp.53-60.