Ultraprecision grinding of the tungsten carbide
22nd International Congress of Mechanical Engineering (COBEM 2013) November 3-7, 2013, Ribeirão Preto, SP, Brazil. Copyright © 2013 by ABCM
Abstract
The surface characteristics and removal mechanism of tungsten carbide cobalt (WC-Co) materials with different compositions (88% WC, 90% WC and 94% WC) in Ultraprecision Grinding were investigated. The motivation for this study is the material’s high hardness and potential application for micromolds. The tests were conducted using an ASG 2500 Rank Pneumo™ Surface Generator. A V-shaped metal-bond 75mm diameter diamond wheel was used. The surface roughness (arithmetic average value Ra) of the three microstructural tungsten carbides was measured, using a white-light optical interferometer (Wyko™ NT1100). The results of the grinding process indicate that the average surface roughness was smaller than 10 nm Ra for all grain sizes. The results indicated that, depending on the cutting conditions, it is possible to grind WC in the plastic regime resulting in damage-free smooth surfaces. The grain size of the WC-Co samples and the depth of cut showed little influence on the surface roughness and material removal mechanism without induction of grinding damage in the WC-Co materials. Ultraprecision grinding showed to be a viable option for the fabrication of components made of tungsten carbide with submicrometer surface finish possibly eliminating traditional optical manufacturing processes such as lapping and polishing.
Keywords: ultraprecision, grinding, tungsten carbide, integrity surface
