Abstract
This paper deals with the development of a new type machining system for ultra-precise micro-aspherical parts, which is assisted with electrorheological phenomenon. Now, it is trying to machine the small parts utilizing a micro-grinding and -polishing with the same tool as a series of processes. As a diamond micro-quill for the grinding/polishing processes has a small diameter (0.1-1.0mm), an on-machine truing of the quill is very difficult and a tool life becomes short. A new method is developed, which is named an electrorheological fluid assisted polishing. In this process, polishing slurry is mixture of fine abrasive (diamond, GC or WA) and electrorheological fluid. A strong electric field (0-4kV/mm) is applied between a very sharp tool like a needle (negative electrode) and a fixed electrode on the workpiece surface (positive electrode), and viscosity of the polishing slurry is increased. The abrasive particles gather around the tip of the tool, and are softly held. The necessary instrumentation and control system have been designed and built. The machine has NC controlled 2-axis slide tables driven with ultrasonic linear motors and ultra-precision air spindles. Basic motion errors of the machine were investigated.
