Particle movement patterns and their prediction in abrasive flow machining

Abstract

AbstractAbrasive particle movement pattern is an important factor in estimating the wear rate of materials, especially, as it is closely related to the burring, buffing and polishing efficiency of the abrasive flow machining (AFM) process. There are generally two kinds of particle movement patterns in the AFM process, i.e. sliding–rubbing and rolling. In mechanism, AFM grain–workpiece interaction is taking place in any one or a combination of the possible modes: elastic/plastic deformation by sliding–rubbing grain movement; elastic/plastic deformation by rolling grain movement; chip formation (micro‐cutting) by rubbing grain movement; ridges formation by rubbing and rolling grain movement; and low‐cycle fatigue wear. Therefore, the machining efficiency of a machine part is predominantly dependent upon the particle movement patterns. In this paper, normal load, particle size and hardness of machine parts were investigated to understand the involved parameters of particle movement patterns and propose a computer statistic prediction of particle movement patterns. It has been found that there are two cases. In case of large‐size particles, the ratio of rolling particles is increased with increasing normal load. For small‐size particles, the ratio of grooving particles is increased with increasing normal load and vice versa. When normal load is light, the particle size cannot usually give an effect on movement patterns. That influence will be predominant under heavy normal load. Most of the particles will tend to groove when the particle size is below a certain value. Hardness of the material and their hardness difference for tribological pairs are other important monitors in predicting particle movement patterns. In this research, increasing hardness of materials results in more rolling particles, which results in much less cutting particles. Copyright © 2007 John Wiley & Sons, Ltd.