Manufacturing and characterisation of highly porous metal bonded diamond grinding wheels

Abstract

Currently, there is no economical method for producing porous metal-bonded diamond grinding wheels. The availability of such a method would allow for the combination of the advantages of a highly porous vitrified-bonded grinding wheel with the high strength of a metal-bonded grinding wheel. This work investigates two methods for the production of porous metal-bonded grinding wheels to achieve this goal. It is shown that it is possible to produce porous metal bonds for grinding tools based upon small adjustments to a FAST sintering process. This allows the production of porous metal-bonded grinding tools with existing infrastructure and known bonding systems. A model is derived for the reproducible design of porosity up to 30 % by volume based on manufacturing parameters, as well as the influence of the pore content on the mechanical properties of the bond material. Secondly, a method for evaluating the self-sharpening behaviour of grinding wheel bonds depending on the workpiece material is proposed. In grinding experiments using dense and porous metal-bonded grinding wheels, the increased self-sharpening effect for the porous bond is confirmed as well as a reduction in grinding forces. This shows the high potential of metallic porous bonds with regard to self-sharpening.