Nano-Precision Polishing of Oxygen-Free Copper Using MCF (Magnetic Compound Fluid) Slurry

Abstract

Oxygen-free copper (OFC) is a popular material used for molds/dies in injection molding of plastic lens because of its high ductility, strong impact strength and good thermal conductivity. nanoprecision polishing is essential as the final process in its fabrication. For this purpose, a novel polishing method using magnetic compound fluid (MCF) slurry was proposed. In this article, the construction of an experimental rig to realize the proposed method was described at first. Then the effects of process parameters including MCF slurry composition, workpiece oscillation parameter f/Ap-p and clearance Δ between workpiece and MCF carrier on work-surface roughness and material removal were experimentally investigated. As a result, nanoprecision surface finish of OFC was successfully attained by polishing with MCF slurry and the optimum process parameters (f/Ap-p=30 Hz/4mm, Δ=0.6 mm with an MCF slurry (45wt.% of CIP, 12 wt.% of Al2O3 grain, 3 wt.% of α-cellulose, 40 wt.% of MF) for obtaining the smoothest work-surface were determined.