Investigations on the Development of a New Magnetorheological Grinding Tool for Finishing of Cylindrical Blind Holes Surface

Abstract

Fine finishing of the inner surfaces of cylindrical blind hole (CBH) components is currently in high demand in the manufacturing industry as a means of reducing friction and improving functional efficiency. The industries like automobile, medical, and mould manufacturing are currently looking for fine finished CBH-type components with increased functional performance. Fine finished CBH-type industrial components like moulds are used to make plastic parts such as drosophila vials, bottle caps, light covers, etc. This increases the service life of finished products while also improving their aesthetic appearance and dimensional precision. The other CBH-type components like femoral head-neck taper junction and brake master cylinder also require fine finishing for increasing their functional performance. For the finishing of such CBH-type workpieces in industries, the most common method is to use a traditional handheld grinding technique. In this process, the bonded abrasive wheel is utilized for finishing the CBH workpiece surfaces which result in tensile residual stresses, heat-affected zones, microcracks, and many other defects. Surface fatigue, contact stiffness, and corrosion can all increase if these faults are not removed. Beyond that, there is no control over the finishing forces that act on the workpiece surface during the traditional finishing process. To achieve efficient and defect-free finished surfaces, a permanent magnet-based technique with two tools was recently developed for the MR finishing of longitudinal and bottom flat surfaces of the CBH type workpieces. The use of permanent magnets restricts the in-process control over the finishing forces. Also, this process can be utilized for the finishing of workpieces having a particular diameter size. Therefore, a tool is required for fine finishing of straight or tapered longitudinal and flat end surfaces of the CBH-type workpieces of variable sizes. This is possible only by keeping the tool eccentric from the central axis of the workpiece. Further, in-