Mechanism and techniques of mechanical lapping of nature diamond cutting tools nose arc

Abstract

Rounded diamond cutting tools are used for ultraprecision cutting widely. The lapping qualities of the nose arc play a quite important role on the achieved accuracy of the machined surface. Therefore, it is urgent to solve the high-precision lapping problem of the nose arc. Firstly, based on the periodic bond chain (PBC) model, ratio model of material removal rate is proposed for tool nose arc, in which the {100} crystal plane is oriented as the rake face. And then, the optimal lapping direction is obtained for the nose arc of diamond cutting tools. More over, two lapping methods are proposed for tool nose arc according to the formula of material removal amount. The first is the lapping under variable pressure; the other is the lapping under variable time. After that, a new type lapping machine is designed by top-down method of Pro/Engineering. According to the requirements of the tools, a novel measuring method based on atomic force microscope (AFM) is put forward for nose roundness. A complete system is built for lapping of nature diamond cutting tools' nose arc.