The objective of this part of the report is to present the lastest results on cornmunition under the IFPRI grant that started in 1993. We recall that the objectives of the research are to develop fundamental understanding and techniques to predict communition behaviour from a universal test. An experimental rig was built up to reproduce single impact on a target in an air jet mill. The influence of the material properties on breakdown was investigated in ultra- fine grinding.
Section 1 presents the results of the single particle impact experiments performed with the single jet apparatus. The influence of the size of particle is shown with glass beads and two polymers.
Section 2 gives the results of the study of repeated impacts. Two approaches are used to compare the efficiency with a single impact
Section 3 studies the influence of the process of different hydrargillites on their behaviour at impact.
Morphological analysis tools are used in relation with the classical study (fragmentation profiles).