Diamond tool wear in ultra-precision machining

Diamond has many outstanding properties, such as high hardness, great toughness, high capability up to a nanometric tool cutting edge, high thermal conductivity, low friction, and high wear resistance. Accordingly, it is employed as an efficient tool in ultra-precision machining (UPM). However, diamond tool wear (DTW) in UPM is an inevitable physical phenomenon and even a little DTW will produce a direct impact on nanometric surface roughness. With a focus on diamond's physical characteristics, this paper looks at the current investigations of DTW and posits an improved understanding of DTW in UPM. Firstly, the differences in DTW caused by different workpiece materials are reviewed, as are the factors influencing DTW and its effects. Secondly, the DTW mechanisms are summarized, including DTW anisotropy, DTW features, and DTW behaviors, with diamond tool performances. Thirdly, DTW measuring, DTW monitoring, DTW controlling, and DTW modeling are introduced. Thirdly, different methods for DTW suppression are surveyed with a view to improving the cutting performance of diamond tools. Finally, the challenges and opportunities for DTW, which may be of particular interest for future studies, are discussed with several conclusions.