An Anisotropic Model for the Plastic Response of Powder Compacts


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In this paper we present an anisotropic compaction model based on a generic modeling framework. The model is a generalization of Hill’s anisotropic model to compressible materials and reduces to a Cam-clay type model in the isotropic limit. The model has been calibrated using experimental data for a commercial steel powder obtained from a computer controlled triaxial cell in which the yield surface was probed following loading along different paths in stress and strain space. Closed-form analytical expressions are presented for the yield surface as a function of the inelastic strain. The model has been implemented in the general purpose finite element code ABAQUS. Simulations are presented which explore the effect of a detailed structure of the constitutive law on the compaction response.



Materials Science Forum (Volumes 561-565)

Main Theme:

Edited by:

Young Won Chang, Nack J. Kim and Chong Soo Lee




W. R. Ruziwa and A. C.F. Cocks, "An Anisotropic Model for the Plastic Response of Powder Compacts", Materials Science Forum, Vols. 561-565, pp. 1809-1812, 2007

Online since:

October 2007




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