Plastic flow of saturated, consolidated alumina powder compacts: Particle size and binary mixtures

The flow stresses and relaxed yield stresses of saturated, alumina powder compacts that have been consolidated via pressure filtration were measured in unconstrained uniaxial compression. Two different sized powders, as well as binary mixtures of the two powders, were investigated. Bodies that were consolidated from slurries of larger par; tides had lower flow and relaxed yield stresses, relative to bodies that were made of small particles with the same relative density and solution conditions. This result is primarily due to the lower number of particle-particle contacts per unit volume in the body that was made of the large particles. The flow stress of the body can be controlled by adjusting the fraction of large particles to small particles.