Surface integrity and process simulation in abrasive flow machining

Trends like lightweight construction and functional integration lead to more and more complex workpieces. Often, these workpieces have to be finished after machining. Especially inner contours are difficult to finish. Hence, only a few manufacturing techniques are suitable for deburring, edge rounding and polishing of inner contours. An appropriate solution is abrasive flow machining (AFM) in which a high viscous fluid with abrasive grains is used. Despite the wide usage of AFM in industry, the knowledge about the fundamentals of abrasive flow machining processes is limited. After elaborated test series new findings concerning the surface integrity are presented in this paper. This is done in terms of the regressive development of the surface roughness on the one hand and in terms of the generated edge rounding on the other hand. In this context, it is found, that there is a factor of about 16 between chipped material at the edge and chipped material at the surface. This factor is nearly constant during processing time. Finally, the correlation between processing parameters, surface roughness, edge rounding and material removal rate can be characterized as a result of studies. Moreover, these new findings can be transferred to a comprehensive process model, which is the basis for a reliable process simulation. Due to this progress, predictions of processing results of abrasive flow machining will be possible.