Effect of Slow Cooling in Reducing Pore Size in a Sintered Powder Metallurgical 6061Aluminium Alloy
S. Solay Anand, B. Mohan, T. R. Parthasarathy
DOI: 10.4236/msa.2011.27117   PDF   HTML     5,746 Downloads   10,357 Views   Citations


The usage of powder metallurgy aluminium compacts in lieu of ferrous components in automotives helps to lower vehicle weight. The major drawback in the commercially available press sintered aluminium alloy is porosity which is mainly dependent on the powder metallurgical process parameters such as compaction pressure, sintering temperature and cooling rate after sintering. In this paper the effect of particle size and furnace controlled cooling after sintering on porosity level and micro hardness of an elemental 6061 aluminium alloy has been investigated. Aluminium particle sizes of 20 µm and 150 µm were used. The elemental 6061 aluminium alloy powders are warm compacted at 175 MPa. After sintering for about one hour at 600°C, the aluminium compacts were furnace cooled at the rate of 1°C /min to different temperatures of 500°C, 400°C, 300°C and 200?C. When the cooling temperature after sintering inside the furnace is effected at various temperatures from 600°C to 200°C, for a precipitate hardened aluminium compacts with aluminium particle size of 20 µm, the porosity level reduced by 26% and that for aluminium particle size of 150µm, the porosity level reduced by 23%. Marked improvement in micro hardness value is also observed correspondingly.

Share and Cite:

S. Anand, B. Mohan and T. Parthasarathy, "Effect of Slow Cooling in Reducing Pore Size in a Sintered Powder Metallurgical 6061Aluminium Alloy," Materials Sciences and Applications, Vol. 2 No. 7, 2011, pp. 870-877. doi: 10.4236/msa.2011.27117.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] I. J. Polmear, “Light Alloys-Metallurgy of the Light Metals,” Third edition, Arnold, London, 1995.
[2] D. Slavnich, “Electric and Hybrid Vehicle,” Journal of Automobile Engineering, Vol. 27, 2002, pp. 52-60.
[3] G. B. Schaffer, Material Forum 24, 2000, pp. 109-125.
[4] A. Salak, “Ferrous Powder Metallurgy,” Cambridge International Science Publishing, Cambridge, 1997.
[5] N. Chawala, B. Jester and D. T. Vonk, “Bauschinger Effect in Porous Sintered Steels,” Journal of Materials Science Engineering A, Vol. 346, No. 1-2, 2003, pp. 266- 272. doi:10.1016/S0921-5093(02)00542-7
[6] N. Chawala, D. Babic, J. J. Williams, S. J. Polasik, M. Marcucci and K. S. Narasimhan, “Advances in Powder Metallurgy and Particulate Materials,” MPIF, 2002, p. 104.
[7] N. Chawala, T. F. Murphy, K. S. Narasimhan, M. Koopman and K. K. Chawala, “Axial Fatigue Behavior of Binder-Treated Versus Diffusion Alloyed Powder Metallurgy Steels,” Material Science Engineering A, Vol. 308, No. 1-2, 2001, pp. 180-188. doi:10.1016/S0921-5093(00)01990-0
[8] S. Polasik, J. J. Williams and N. Chawala, “Fatigue Crack Initiation and Propagation of Binder-Treated Powder Metallurgy Steels,” Metallurgical Material Transaction A, Vol. 33A, 2002, pp. 73-81. doi:10.1007/s11661-002-0006-8
[9] R. N. Lumely and G. B. Schaffer, “Precipitation Induced Densification in a Sintered Al-Zn-Mg-Cu alloy,” Journal of Scripta Materials, Vol. 55, No. 3, 2006, pp. 207-210. doi:10.1016/j.scriptamat.2006.04.021
[10] R. N. Lumley and G. B. Schaffer, “Surface Oxide and the Role of Magnesium in Liquid Phase Sintering,” Journal of Scripta Materials, Vol. 35, No. 5, 1996, pp. 589-595. doi:10.1016/1359-6462(96)00195-9
[11] R. N. Lumley and G. B. Schaffer, “The Effect of Additive Particle Size on Sintered Al-Cu Alloys,” Journal of Scripta Materials, Vol. 39, No. 8, 1998, pp. 1089-1094. doi:10.1016/S1359-6462(98)00278-4
[12] ASM Handbook Metallography and Microstructures, Vol. 9, 2004.
[13] M. Rahimian, N. Ehsania, N. Parvin and H. Baharvandi, “The Effect of Particle Size, Sintering Temperature and Sintering Time on the Properties of Al–Al2O3 Composites, Made by Powder Metallurgy,” Journal of Material Processing Technology, Vol. 209, No. 14, 2009, pp. 5387- 5393. doi:10.1016/j.jmatprotec.2009.04.007
[14] D. Kent, G. B. Schaffer and J. Drennan, “Age Hardening of a Sintered Al-Cu-Mg-Si-(Sn) Alloy,” Journal of Materials Science Engineering A, Vol. 405, No. 1-2, 2005, pp. 65-73. doi:10.1016/j.msea.2005.05.104
[15] N. Showaiter and M. Youseffi, “Compaction, Sintering and Mechanical Properties of Elemental 6061 Al Powder with and without Sintering Aids,” Journal of Materials and Design Vol. 29, No. 4, 2008, pp. 752-762. doi:10.1016/j.matdes.2007.01.027
[16] J. W. Martin, “Precipitation Hardening,” Second Editon, Oxford, 1998.
[17] W. Bonfield and P. K. Datta, “Precipitation Hardening in Al–Cu–Si–Mg Alloy at 130-220?C,” Journal of Material Science, Vol. 11, 1976, pp. 1661-1666. doi:10.1007/BF00737522
[18] L. Dutta, C. P. Harper and G. Dutta, “The Control of Grain Size and Distribution of Particles in a (6061 Alloym/(Al2O3)P Composite by Solutionizing Treatment,” Journal of Metallurgical and Materials Transactions A, Vol. 25, 1994, pp. 1591-1602. doi:10.1007/BF02668525

Copyright © 2022 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.