Study of edge radius effects in mechanical micro-machining

Abstract

In mechanical micro–machining, the feature size ranges from tens of micrometres to less than a millimetre in size. At this level of cutting, the tool cannot be considered as a sharp tool, as the uncut chip thickness is comparable to the tool edge radius. Due to technological limitations, it is not possible to manufacture a perfectly sharp tool. Researchers have studied various aspects of edge radius of tools, such as size effect, minimum chip thickness effect, ploughing phenomena, etc. In the present study, FEM analysis of the orthogonal machining is presented to study the stress state ahead of the tool, in the machined surface and in the layers encompassing the chip. The uncut chip thickness in this study is chosen to be more than the edge radius of the tool. The study indicates, an optimum value for edge radius can be found and used for processes of constant uncut chip thickness.