抄録
To clarify the viscous behaviors of powder when sample which had been compressed once was recompressed, the relation between compression stress and displacement of upper punch was studied. There appeared a hysteresis loop in the stress-displacement diagram and from the loop area loss energy depending on the viscosity of sample was calculated, and the relation between loss energy and compression time was investigated. Some informations on the influence of additives upon loss energy were also obtained. It was proved that the fact that in the process of tabletting larger compression force was required when compression velocity was increased was the result of increasing of loss energy based on the viscosity of sample.
