ABSTRACT
In the processing of particulate solids, there are circumstances under which interparticle and particle-wall impacts cause damage to the particles. The impact of particles causes a transient stress whose magnitude depends on a number of factors such as impact velocity, particle size, material properties, and contact geometry. To address the impact breakage of particulate solids on a fundamental basis, fracture mechanics are used to define the conditions for propagation of various types of cracks. i.e. radial and median cracks for the fragmentation, and lateral cracks for chipping. The transition velocities from plastic deformation to chipping and from chipping to fragmentation are important features of particle breakage by impact. Impact damage depends on the mode of failure, which in turn depends on material properties and contact geometry. The rate of breakage and particle transition size and velocities are all affected by the mechanical characteristics such as hardness, toughness and stiffness.
