In order to study the effects of particle properties on the solid particle erosion mechanisms of brittle bulk materials, six target materials were tested using two different powders (alumina and glass) at velocities ranging from 25 to 75 m/s. Following in depth characterizations of the targets and of the particles before and after testing, it was found that lateral fracture was the dominant material removal mechanism as predicted by the elasto-plastic theory of erosion. In the case of glass powder, for which the hardness of the particle is lower than the hardness of the target, particle deformation and fragmentation were found to be important factors explaining lower erosion rates. The higher than predicted velocity exponents point toward a velocity-dependent damage accumulation mechanism which was found to be correlated to target yield pressure (H (3) /E (2)). Although damage accumulation seems to be necessary for material removal when using both powders, the effect is more pronounced for the softer glass powder because of kinetic energy dissipation through different means.