Skip to main content
Log in

Fluidized bed heat treatment of cast Al-Si-Cu-Mg alloys

  • Published:
Metallurgical and Materials Transactions A Aims and scope Submit manuscript

Abstract

The effects of fluidized bed heat treatment on the microstructural and mechanical properties of Al-Si-Cu-Mg cast alloys, namely, 354 and 319, were studied. The heating rate in fluidized beds (FBs) is greatervis-à-vis conventional electrical resistance furnaces (CFs). The high heating rate in FBs increases the kinetics of metallurgical phenomena such as Si fragmentation and spherodization during solution heat treatment, as well as the precipitation rate of phases such as Al5Cu2Mg8Si6 and Al2Cu during aging. It is observed that the dissolution rate of phases such as Mg2Si and Al5Cu2Mg8Si6 takes place very rapidly. The solution heat treatment of 319 alloy using FB results in complete dissolution of Mg2Si and Al5Cu2Mg8Si6 particles within 45 minutes. However, for phases such as Al2Cu and Ferich intermetallics, the dissolution rate is relatively slow. Even on prolonged solution heat treatment for 6 hours, these phases do not dissolve completely. It is observed that incomplete dissolution of the Al2Cu phase does not significantly affect tensile properties of T4-treated alloys. The optimum solution heat-treatment time in FB for both 354 and 319 alloys is 45 minutes at 527 °C and 493 °C, respectively. Thermal analysis shows an exothermic peak owing to recrystallization and coarsening of eutectic grains during solution heat treatment. The high heating rate in FB causes this transformation to take place at a lower temperature than in CF. It is observed that the nucleation rate of Al5Cu2Mg8Si6 during aging in FB is greater than using CF. Thermal analysis of samples during the ramp-up stage while aging using FB did not show any phase transformation, while those using CF show two endothermic transformations, which are most likely due to the dissolution of GP zones or the co-cluster of solutes. Aging at 200 °C results in a greater number density of precipitates than those at 240 °C. The tensile strength of samples aged at 200 °C is greater than those aged at 240 °C, because the amount of precipitates formed at 200 °C is greater than that at 240 °C. The total heat-treatment time for T6 temper is less than 2 hours in FBs, which is a significant reduction in heat-treatment time, as well as energy consumption.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. D. Apelian, S. Shivkumar, and G. Sigworth:AFS Trans., 1989, vol. 89–137, pp. 727–41.

    Google Scholar 

  2. ASM Handbook, vol. 2,Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASM INTERNATIONAL, Materials Park, OH, 1991, pp. 159–67.

  3. S. Shivkumar, L. Wang, and C. Keller:Z. Metallkd., 1994, vol. 85 (6), pp. 394–99.

    CAS  Google Scholar 

  4. Z. Li, A.M. Samuel, F.H. Samuel, C. Ravindran, S. Valtierra, and H.W. Doty:Mater. Sci. Eng., A, 2004, vol. 367 (1–2), pp. 96–110.

    Google Scholar 

  5. A.M. Samuel and F.H. Samuel:Metall. Mater. Trans. A, 1995, vol. 26A (9), pp. 2359–72.

    CAS  Google Scholar 

  6. E.J. Martinez, M.A. Cisneros, S. Valtierra, and J. Lacaze:Scripta Mater., 2005, vol. 52 (6), pp. 439–43.

    Article  Google Scholar 

  7. L. Backerud, G. Chai, and J. Tamminen:AFS/SKANALUMINIUM, 1990, vol. 71, pp. 79–85.

    Google Scholar 

  8. J.H. Sokolowski, M.B. Djurdjevic, C.A. Kierkus, and D.O. Northwood:J. Mater. Processing Technol., 2001, vol. 109 (1–2), pp. 174–80.

    Article  CAS  Google Scholar 

  9. R.X. Li, R.D. Li, Y.H. Zhao, L.Z. He, C.X. Li, H.R. Guan, and Z.Q. Hu:Mater. Lett., 2004, vol. 58 (15), pp. 2096–101.

    Article  CAS  Google Scholar 

  10. D.L. Zhang and L. Zheng:Metall. Mater. Trans. A, 1996, vol. 27A (12), pp. 3983–991.

    Article  CAS  Google Scholar 

  11. S. Zafar, N. Ikram, M.A. Shaik, and K.A. Shoaib:J. Mater. Sci., 1990, vol. 25 (5), pp. 2595–97.

    Article  CAS  Google Scholar 

  12. H.G. Kang, M. Kida, H. Miyahara, and K. Ogi:AFS Trans. 1999, vol. 107, pp. 507–15.

    CAS  Google Scholar 

  13. P. Oullet and F.H. Samuel:J. Mater. Sci., 1999, vol. 34 (19), pp. 4671–97.

    Article  Google Scholar 

  14. H. Beumler, A. Hammerstad, B. Wieting, and R. Dasgupta:AFS Trans., 1986, vol. 96, pp. 1–12.

    Google Scholar 

  15. S.K. Chaudhury, L. Wang, and D. Apelian,AFS Trans., 2004, vol. 112, Paper 04-055, pp. 1–16.

    Google Scholar 

  16. R.W. Reynoldson:Heat Treatment in Fluidized Bed Furnaces, ASM INTERNATIONAL, Materials Park, OH, 1995, pp. 34–36.

    Google Scholar 

  17. J. Keist:J. Met., 2005, vol. 57 (4), pp. 34–39.

    CAS  Google Scholar 

  18. D. Apelian and S.K. Chaudhury:J. Phys. IV, 2004, vol. 120, pp. 555–62.

    CAS  Google Scholar 

  19. D. Holland-Moritz, D.M. Herlach, and K. Urban:Physical Rev. Lett., 1993, vol. 71 (8), pp. 1196–99.

    Article  CAS  Google Scholar 

  20. X. Yan, L. Ding, S.L. Chen, F. Xie, M. Chu, and Y.A. Chang:Light Metals, 130th TMS Annual Meeting, New Orleans, LA, Feb. 11–15, 2001, TMS, Warrendale, PA, 2001, pp. 1091–97.

    Google Scholar 

  21. S.L. Chen, F. Zhang, S Daniel, F.Y. Xie, X.Y. Yan, Y.A. Chang, R. Schmid-Fetzer, and W.A. Oates:J. Met., 2003, vol. 55 (12), pp. 48–51.

    CAS  Google Scholar 

  22. M.H. Mulazimoglu, N. Tenekdijev, B.M. Closet, and J.E. Gruzleski:Cast Met., 1993, vol. 6, pp. 16–28.

    Google Scholar 

  23. L.A. Narayanan, F.H. Samuel, and J.E. Gruzleski:Metall. Mater. Trans. A, 1994, vol. 25A (8), pp. 1761–73.

    CAS  Google Scholar 

  24. Q.G. Wang and C.J. Davidson:J. Mater. Sci., 2001, vol. 36 (3), pp. 739–50.

    Article  CAS  Google Scholar 

  25. M. Caudillo, M. Herrera-Trejo, M.R. Castro, E. Ramirez, C.R. Gonzalez, and J.I. Juarez:J. Biomed. Mater. Res. A, 2002, vol. 59 (2), pp. 378–85.

    Article  CAS  Google Scholar 

  26. F. Vermolen, K. Vuik, and S. Van der Zwaag:Mater. Sci. Eng. A, 1998, vol. 254 (1–2), pp. 13–32.

    Google Scholar 

  27. M. Slamova, M. Karlik, M. Cieslar, B. Chalupa, and P. Merle:Kovove Mater., 2002, vol. 40 (6), pp. 389–401.

    CAS  Google Scholar 

  28. C.H. Caceres, J.H. Sokolowski, and P. Gallo:Mater. Sci. Eng. A, 1999, vol. 271 (1–2), pp. 53–61.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Chaudhury, S.K., Apelian, D. Fluidized bed heat treatment of cast Al-Si-Cu-Mg alloys. Metall Mater Trans A 37, 2295–2311 (2006). https://doi.org/10.1007/BF02586148

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02586148

Keywords

Navigation