The objective of this work is to develop a material model for the compaction of a ceramic powder, suitable for use in the finite element simulation of wire forming operations using the "powder in tube" technique. The specific material investigated is a fine grained Bi{sub}2Si{sub}2CaCu{sub}2O{sub}8 (Bi-2212) powder, which is a precursor to a high temperature superconductor, and is being investigated for use in a "wind and react" coil manufacturing strategy. The powder was precompacted at a range of pressures, machined to specimen shape as needed, and tested. Properties measured included elastic moduli, bend strength, compression strength, and yield and flow response to triaxial compaction. A material model was constructed as a set of mathematical algorithms which approximated the measured material behavior. The model is isotropic, expressed in terms of the first two stress invariants, uses relative density as the internal variable, and is set so that strength, yield stress, and stiffness are zero at the pouring density. The structure in stress space is an elastic region, bounded by a friction line and a yield cap. The yield cap does not conform to associative flow or convexity, which may be attributed to some combination of granular and plastic flow.
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