Abstract
In general, the heterogeneity of powder bulk density distribution formed in the powder compacts of powder plastic processes determines the mechanical strength and the dimensional accuracy of the final product and therefore is taken to be one of the most important problems to be elucidated. In order to elucidate this problem, the methods to measure the heterogeneity of the powder bulk density of powder compact, especially including loose one, can be considered to play a very important role. However, they have not yet sufficiently been developed up to now. Then, in this paper, as a first step to overcome this difficulty, the plunger penetration into powder was noticed. And the possibility to estimate the above heterogeneity using the acoustic emission generated at the above penetration experiments was experimentally discussed. As a result, it was pointed out that the distance between neighbouring loose powder bulk density zones can be predicted from acoustic emission data.
