抄録
The relation between stress and strain in the compaction of dry powdered materials is generally given by Tani's equation (σ=kεn). On the other hand, the σ-ε relation of damp powders under low compacting stress must be corrected in accordance with the progress of compaction because of the agglomerative nature of floclike mass. As has been reported previously, the σ-ε relation of damp powders which does not bring about deformation and cracks of constituent particles is shown as σ=kiεni+di, where subscripts refer to the consecutive opposing processes of three stages.
The consistency of damp powders dealt with in this work follows the relation given above, and also the expressions for three stages of compaction are newly characterized by
Kψi=(σ-di)(1+bi)-1·ε-1
where Kψi=ki(1+bi)-1, di=ci/(1+bi), ni=1+bi, and these constants depend on the mechanical properties of particle packing structure. In particular, the degree of performance for the compaction of damp powdered materials can be expressed better with the help of consistency constant Kψi. It appears that the above relation is useful enough to yield an understanding of the packing mechanism of damp powder beds.
