Modification of the Density-Pressure Relationship due to the Internal Friction and Cohesion of a Powder Mass Undergoing Closed Die Compaction

Abstract:

The existing density-pressure laws for a powder undergoing die compaction fit experimental data very well except for the low-pressure end of curves for some materials (SiC, Al2O3). To improve this, density - pressure relationship was modified by considering the internal friction and cohesion. For constant internal friction and vanishing cohesion, the modified relationship became mathematically equivalent to the existing one. For density-dependent friction, the modified and original relationships were able to provide nearly the same densities at medium and higher pressures but slightly different values at the low-pressure region.

• Periodical: Key Engineering Materials (Volume 409)
• Pages: 334-337
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.409.334
• Online since: March 2009
• Authors: Miriam Kupková
• Keywords: Cohesion, Density-Pressure Relationship, Die Compaction, Internal Friction

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