Internal mirror grinding with a metal/metal-resin bonded abrasive wheel

Precision internal cylindrical surfaces are increasingly utilized in industries where highly efficient methods to fabricate such surfaces are of great importance. Presently, several processes usually performed on different machines are used successively to achieve a mirror finish. In this paper, a novel method is presented to accomplish roughing and finishing processes on one machine, using super abrasive cast-iron-bond CBN (CIB-CBN) wheels and metal-resin-bond CBN (MRB-CBN) wheels. Two dressing methods, electrolytic interval dressing and electrolytic in-process dressing (ELID). are also developed for these wheels respectively. The CIB-CBN wheel is trued by an on-machine electrical discharge truer (EDT) and dressed at intervals with a pipe-shape electrode; the MRB-CBN wheel is dressed in process, in which no specific dressing electrode is utilized, instead the conductive workpiece acts as a dressing electrode. Precision grinding has been carried out on an ordinary grinder with an attachment for internal cylindrical grinding. Wheels of #325, #1200, #2000, and #4000 grit sizes have been applied in the process to obtain mirror surfaces. (C) 2000 Elsevier Science Ltd. All rights reserved.