Development and application of material extrusion produced ultra-fine diamond grinding tools for machining hard brittle materials

Abstract

Hard-brittle materials have found application in numerous advanced technologies. The machining of these materials necessitates an increase in the efficiency and sustainability of production, while maintaining the requisite quality and precision. Achieving this objective requires the advancement of machining processes, including the development of abrasive technologies with geometrically undefined cutting edges. In this context, innovations in grinding tool development are an essential approach that can focus on efficient tool production as well as enhanced tool properties, such as fine, partially elastic tools to enable a ductile grinding regime for high workpiece quality. In this paper, a novel composite material consisting of diamond grains, zirconium oxide particles, and polyamide 12 (PA 12) is presented. This composite material enables the flexible process of additive manufacturing (AM) of diamond-based ultra-fine grinding tools. The filament-based material extrusion (MEX) process is utilized to fabricate ultra-fine grinding tools with a selected tool geometry, employing a range of additive manufacturing parameters. These parameters were examined in terms of material properties. Preliminary material analyses indicate that the distribution of the filament’s components is homogeneous and that the bond between the layers is solid. In a CNC grinding process, the performance of AM tools was successfully evaluated using planar samples made of fused silica. A comparison was conducted to determine the grinding performance of AM tools in relation to that of a conventional synthetic resin bond tool. By ultra-fine grinding application of the AM tools, it is possible to accomplish reproducible low roughness values Rq ranging from 10 to 14 nm. This result corresponds to a substantial reduction in roughness, reaching 97%, when compared to the initial fine ground surface. The results of the study indicate that additively manufactured ultra-fine grinding tools have a promising potential to enable economical, efficient production of optical components with high surface requirements.