Densification of nanosized alumina powders by hot isostatic pressing (HIP)
- Forschungszentrum, Karlsruhe (Germany)
The densification of nanosized alumina powders to compacts of nearly theoretical density by Hot Isostatic Pressing was the aim of this work. Three types of powders produced by the so called exploding wire technique in the mesh size between 20 to 80 nm were used. Because of the big internal friction during dry pressing the densities achieved were only in the range of about 30% TD. Therefore it was necessary to use a second post densification step by cold isostatic pressing (CIP). With pressures as high as 750 MPa the authors received a density of 58% TD. The pellets were sealed in capsules of stainless steel which were densified at different temperatures between 900 C and 1,350 C with pressures between 120 and 300 MPa. The resulting compacts were examined by scanning electron microscopy. The resulting phases were determined by X-ray diffraction. Grain size measurement at the as fabricated compacts was a decisive criterion for the success of the experiments.
- OSTI ID:
- 442806
- Report Number(s):
- CONF-960515--; ISBN 0-87170-568-0
- Country of Publication:
- United States
- Language:
- English
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