Experimental investigations into rotating workpiece abrasive flow finishing

Abrasive flow finishing (AFF) is used to deburr, polish or radius surfaces and edges by flowing a semisolid abrasive medium over the intended surface to be finished. Such finishing operations play a crucial role in manufacturing process of machine parts. The cost escalates sharply when the requirement is to achieve surface roughness values near nano levels. The need for finishing is to avoid power losses due to friction, increase the wear resistance and to provide a long serviceable life to the equipment. AFF is used in the industries especially in the case of finishing complex internal and external shapes. However, AFF is a time consuming process and any effort to reduce the process time even marginally saves production time and cost of the finished product. In the present study, an effort is made towards improving the performance of AFF process by providing rotary motion to the workpiece (R-AFF: rotational abrasive flow finishing). Preliminary experimental comparative study is done on AFF and R-AFF processes to compare their process performance in terms change in Ra (ΔRa) and material removal. Later complete experimental study on R-AFF is conducted using central composite rotatable design and the responses are plotted using response surface methodology. The workpiece materials used in the present study are Al alloy, Al alloy/SiC (10%) and Al alloy/SiC (15%) metal matrix composites (MMCs). The results of R-AFF are encouraging. The present study shows that rotational speed of workpiece has significant effect on output responses (ΔRa). Indigenously developed semi solid abrasive laden medium is used in the present study. Overall, the experiments have shown that R-AFF has a very promising future for the industries in terms of better finishing.