Compaction behaviour of agglomerated alumina powders

Date

1997-03-01

Author

Briscoe, Brian J.
Özkan, Necati

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The effects of agglomerate properties, such as the binder type, binder content, moisture level, and agglomerate size, on a model compaction process was investigated by using green density-pressure interrelationships for a range of agglomerated alumina powders. The model compaction process involved single ended nominal uniaxial stress transmission in a cylindrical die. The influences of the sample aspect ratio, die wall lubrication, and compaction rate were also investigated. Two types of water soluble polymeric agents, a poly(vinyl alcohol) (PVA) and a poly(ethylene glycol) (PEG), were used. It was shown that certain agglomerate properties have a strong influence upon the compaction behaviour of these ceramic powders. The extent of the compaction is enhanced by using agglomerates with a low agglomerate yield point. In the PVA system, the agglomerate yield points decreased with increasing moisture content. The compaction behaviour of the agglomerates showed a rate dependency, that is, the compaction is retarded with increased pressing rate. The green densities of the compacts prepared in the unlubricated die were lower than those of the compacts prepared in the lubricated die due to the higher wall frictional forces operating in the unlubricated die.

Subject Keywords

Compaction, Compaction curves, Binders , Agglomerates

URI

https://hdl.handle.net/11511/30141

Journal

Powder Technology

DOI

https://doi.org/10.1016/s0032-5910(96)03210-x

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

B. J. Briscoe and N. Özkan, “Compaction behaviour of agglomerated alumina powders,” Powder Technology, pp. 195–203, 1997, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30141.