Experimental and numerical studies of microsphere oblique impact with planar surfaces

Oblique impact experiments have been carried out with stainless-steel micro spheres and silicon surfaces under a range of impact velocities from 0.45 t o 1.90 m s(-1) and different incident angles. When the normal velocity comp onent for oblique impact is less than the capture velocity as seen for norm al impact, no capture was observed. The experimental results also reveal th at the pattern of impulse ratio variation with incident angle varies with d ifferent initial impact velocities. Furthermore, the measured coefficient o f restitution values can be predicted by a dynamic simulation model, and th e measured impulse ratios can be matched if the microspheres are assumed to have initial angular velocities. (C) 2000 Elsevier Science Ltd. All rights reserved.