Suppression mechanism of tool wear by phosphorous addition in diamond turning of electroless nickel deposits

An appropriate phosphorous addition to electroless nickel deposits remarkably reduces tool wear in diamond turning. To understand the wear suppression mechanism of phosphorous addition, erosion tests simulating tool wear process and ab initio molecular dynamics calculations of interactions between diamond and Ni-P and Ni are carried out. The erosion tests show that carbon diffusion into the workpiece is reduced, and the ab initio calculations suggest that dissociation of carbon atoms on diamond surface due to the interaction with the workpiece is reduced. The results suggest that another possible additive to suppress tool wear can be found by the method proposed. (C) 2010 CIRP.