High-Temperature Extrusion Behavior of a Superplastic Zirconia-Based Ceramic |
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Authors: | Bruce J. Kellett Claude Carry Alain Mocellin |
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Affiliation: | Laboratoire de Céramique, Ecole Polytechnique Fédérale de Lausanne, Swiss Federal Institute of Technology, CH-1007, Lausanne, Switzerland |
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Abstract: | Workability of 3-mol%-yttria-stabilized tetragonal ZrO2 has been gauged through a series of extrusion experiments performed under vacuum with graphite dies at 1500°C and 35 MPa piston stress. It is shown that dense and smooth extrusions can be obtained from solid billets when graphite paper is used as a lubricant. Sigmoidal dies and conical dies with cone angles of 18.4°, 26.6°, and 45° and diameter ratios of 1.5, 2, and 3 were used to explore extrusion behavior. Observed piston velocities correspond to what may be predicted from the experimental uniaxial constitutive creep equation and a simple slab analysis. A precise analysis, however, is not attempted because of lack of steady-state behavior of the material itself. |
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Keywords: | zirconia extrusion processing yttrium rheology |
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