A constitutive model for stage 2 sintering of fine grained materials; 2: Effects of an interface reaction

Journal Article · Fri Apr 01 04:00:00 EST 1994 · Acta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-7151(94)90139-2· OSTI ID:5115469

Pan, J; Cocks, A C.F. ^[1]

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1. Cambridge Univ. (United Kingdom). Engineering Dept.

In this paper, a nonlinear constitutive model is developed for stage 2 sintering of powder compacts by grain-boundary diffusion where energy is dissipated not only in driving the flux of material around the grains but also in overcoming an interface reaction. A three dimensional material model composed of a uniform array of tetrakaidecahedra shaped grains with spherical pores at each grain-boundary vertex is adopted. The interface reaction is assumed to be a function of the grain-boundary separation rate in a power law form as suggested by Cocks. The set of kinematically compatible fields of grain-boundary separation rates, matter flux along grain-boundaries and macroscopic strain-rate proposed in the first part of this paper are used to obtain a lower bound to the scalar macroscopic strain rate potential using the lower bound theorem described by Cocks for the coupled grain-boundary diffusion and interface reaction problem. The optimum magnitudes of the adjustable parameters used to describe the kinematic fields are determined numerically and suitable analytic forms of the strain-rate potential are proposed, based on results of these computations.

• OSTI ID: 5115469
• Journal Information: Acta Metallurgica et Materialia; (United States), Journal Name: Acta Metallurgica et Materialia; (United States) Vol. 42:4; ISSN 0956-7151; ISSN AMATEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
ANALYTICAL SOLUTION
CERAMICS
DATA
FABRICATION
INFORMATION
MATHEMATICAL MODELS
NUMERICAL DATA
NUMERICAL SOLUTION
POWDERS
SINTERING
THEORETICAL DATA