Two start and Three Start Helical Abrasive Flow Machining for Brittle Materials

Abstract

In the experimental investigation on drill bit assisted AFM setup, a developed spline, two start helical profile and three start helical profile have been studied. It has been found that the use of new developed profile led to an improvement in the response parameter of percentage improvement in surface finish and material removal.Drill bit assisted abrasive flow machining is a non-conventional finishing operation. Before the advent of drill bit assisted abrasive flow machining simple abrasive flow machining was used. In simple abrasive flow machining media is simply move up and down through the work piece. In drill bit assisted abrasive flow machining a drill bit is used which passes through the work piece which helps to define the path of media responsible for finishing operation. In the present work three types of drill bits are used spline, two star helical and three star helical.For the design of experiment, the taguchi method approach has been employed. L9 OA has been used for the plan of experiments.The three process parameters viz drill bit type, number of cycle, extrusion pressure all have significant effect for the response parameter of MR .The result shows that type of rod have 33.4%, extrusion pressure have 23.46% and number of cycle have 19.53% contribution for response parameter of MR. At selected parameters a maximum improvement of 69.06% has been observed in the Surface finish. With the initial roughness 6.2 microns, an improvement to 1.91 has been observed on the inner cylindrical surface of the cast iron work piece.