Effectiveness of Hard Turning

Abstract

Hard turning is a turning operation performed on hard materials (hardness more than 45 HRC) in order to reach surface roughness close to that obtained in grinding. The development of this technology was accompanied by the development of new cutting materials such as cutting ceramics, cubic boron nitride and polycrystalline diamond. Especially cubic boron nitride has found its use in hard part turning operations because of its characteristics. However, new cutting materials result in new questions, which researchers are trying to solve. The major consideration for a user of this relatively new technology is the quality of parts produced and how the new cutting material will behave during machining. This paper aims to document and describe the process of wear on the cutting edge of a tool made from cubic boron nitride of a different grade and with a different geometry of the cutting edge, and its influence on surface roughness and quality. Wear was documented by a digital microscope with measurement option. Surface roughness was measured by a roughness meter. A notable observation from this research is that the flank wear of the cutting tool has a large impact on the quality of machined parts (especially surface finish and surface integrity) [1].

The Effect of Cutting Tool Geometry on Surface Integrity: A Case Study of CBN Tools and the Inner Surface of Bearing Rings

“…Moreover, when harder materials underwent machining with chamfered tools, an increase in both the axial and the circumferential residual stresses has been reported for increased cutting speeds [18]. Adamik et al examined the process of different geometry cutting edge wear and its effect on machined surface quality [19]. They pointed out that the flank wear had a large impact on the final component's quality in terms of surface integrity and roughness.…”

Hard Turning on JIS S45C Structural Steel: An Experimental, Modelling and Optimisation Approach

“…The technological advancement of this innovative technology is developing with the incorporation of newer advanced cutting tools for example cemented carbide, ceramics, and cubic boron nitride and polycrystalline diamond. The focal goal of the manufacturers and scientific researcher of this new process is the production of quality components and behaviour of new cutting tool material during the process [1]. Indeed, the crucial significant characteristics of hard turning are noticeable removal of material in a single operation rather than an extensive grinding process to diminish production processing time, cost of production, surface quality, and setup time to remain competitive.…”