Abstract
This paper describes a study of the unloading characteristics of compacts made from the uniaxial compression of metal powders in a cylindrical die. Spherical, irregular and dendritic copper powders and spherical stainless-steel powder were investigated to determine size, shape and material effects on the unloading response. This response was characterized in terms of Young's modulus and Poisson's ratio. Measures of these quantities were made at different relative densities by unloading from different peak axial stresses. With both parameters, there was a strong dependence on particle shape. The load response of lightly compressed material was found to be dominated by its particulate nature and interparticle forces. Unloading material in this condition gave values of Young's modulus that increased slightly and Poisson's ratio that decreased with increasing values of relative density. In contrast, the load response of heavily compressed material was found to be similar to that of a porous solid. Unloading material in this condition gave values of Young's modulusthat increased more steeply and Poisson's ratio that increased with increasing values for the starting relative density. Transition between these two types of behaviour depended on the particle shape, and also, to a lesser extent, the particle material. © 1998 Kluwer Academic Publishers
Similar content being viewed by others
References
P. C. Carnavas and N. W. Page, to be published.
W. B. Crandall, (1960) see Reference [3].
R. M. Spriggs, J. Amer. Ceram. Soc. 44 (1961) 628.
S. M. Lang, (1960) see Reference [11].
J. A. Haglund and J. A. Hunter, J. Amer. Ceram. Soc. 56 (1973) 327.
P. Panakkal, H. Willems and W. Arnold, J. Mater. Sci. 25 (1990) 1397.
C. J. Yu, R. J. Henry, T. Prucher, S. Parthasarathi and J. Jo, in Proceedings of Powder Metallurgy World Congress, Vol. 6 (Metal Powder Industries Association, Princeton, NJ, 1992) p. 319.
Coble and Kingery (1956) see Reference [3].
S. B. Brown and G. G. A. Weber, in “Modern Developments in Powder Metallurgy”, Vol. 18–21 (Metal Powders Industry Federation, Princeton, NJ, 1988) p. 465.
C. J. Yu and T. Prucher, in 'Powders, Characterization, Testing and Quality Control; Advances in Powder Metallurgy and Particulate Materials, Vol. 1 (Metal Powder Industries Association, Princeton, NJ, 1993) p. 273.
E. A. Dean, J. Amer. Ceram. Soc. 66 (1983) 847.
J. C. Wang, J. Mater. Sci. 19 (1984a) 801.
T. J. Watson and J. A. Wert, Metall. Trans. A 24A (1993) 2071.
R. M. German, “Powder Metallurgy Science”, 2nd edn (Metal Powder Industries Association, Princeton, NJ, 1994).
A. K. Maitra and K. K. Phani, J. Mater. Sci. 29 (1994) 4415.
M. Arnold, A. R. Boccaccini and G. Ondarek, ibid. 31 (1996) 1643.
H. A. Kuhn and C. L. Downey, Int. J. Powder Metall. 7 (1971) 15.
B. O. Hardin and G. E. Blandford, J. Geotech. Engng 115 (1989) 788.
M. Hehenberger, P. Samuelson, O. Alm, L. Nilsson and T. Olofsson, in IUTAM Conference on the Deformation and Failure of Granular Materials, Delft, September 1982, p. 381.
P. C. Carnavas and N. W. Page, in MECH-94 International Mechanical Engineering Congress, Perth, Western Australia, 15–19 May 1994, Preprints of Papers, Vol. 2 (The Institution of Engineers Australia, 1994) p. 24.
B. Bever, “Encyclopaedia of Materials Science and Engineering” (Plenum Press, New York, 1986).
S. Kalpakjian, “Manufacturing Processes for Engineering Materials” (Wiley, Chichester, 1985).
P. C. Carnavas, PhD thesis, University of Queensland (1996).
J. C. Wang, J. Mater. Sci. 19 (1984b) 809.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Carnavas, P., Page, N. Elastic properties of compacted metal powders. Journal of Materials Science 33, 4647–4655 (1998). https://doi.org/10.1023/A:1004445527430
Issue Date:
DOI: https://doi.org/10.1023/A:1004445527430