Increasing workpiece peripheral speed as a means for improving ergonomics of cylindrical up grinding with cubic boron nitride tools

Abstract

The author pioneered in experimentally finding out that an increase in the workpiece peripheral speed proper in a wide range invariantly leads to a definitely better surface roughness, i.e., smaller thickness of cut, suggesting an improvement in the process ergonomics, in cylindrical centered up grinding under elastic attrition and linear wear conditions, with cubic boron nitride tools of various specifications, on the grinders differing in static stiffness (8.3 and 12.0 N/μm), with a wheel speed ranging from 32 to 91 m/s. A comparative assessment of grinding processes with a fixed and controllable levels of forced vibrations at idling speed has demonstrated that the weakening of the positive influence of the speed factor on the surface roughness and thickness of cut with increasing workpiece speed proper and/or wheel speed is due to the vibration-induced suppression—an increasing amplitude of the wheel-workpiece vibration displacements at rotational speeds of the wheel, workpiece, and other elements of the grinder-workpiece-tool system. Some recommendations are offered of how to improve the ergonomics of cylindrical up grinding with cBN tools by increasing the workpiece speed proper.