- In this paper we present an experimental analysis of an impact mill that includes a sensitivity analysis followed by an analysis of the main phenomena related to milling, such as agglomeration of the fine product, energy consumption, and product flow ability and tendency to cake. A simple analysis shows that the main mechanism controlling the grinding process is impact and that the shear loads are minor, despite the fact that the pins are rotated within a narrow gap with a sieve. We also show the effect of the repetition of impact loads (when not using a sieve) that is known as fatigue. Furthermore, we analyze the energy consumption and show that for our system the results compare well with Bond's model. Finally, we show how the flow ability of the product is affected by the grinding parameters, and that the surface activation of the particles caused by the mechanical loads leads to a decrease in flow ability and an increase in the tendency to cake.