抄録
In order to develop CBN finishing hobs, the cutting performance of the sintered CBN tool is valued based on the intermittent turning tests. The sintered CBN cutting tool is very hard but fragile. The cutting edge of hob is liable to break, because the cutting mechanism on the hobbing is a kind of intermittent cutting. chamfering of the cutting edge is effective as a prevention against chipping. In this paper, first, the optimum form and size of chamfer is found out based on cutting tests. Secondly, the tool wear and the surface roughness are investigated under various cutting conditions. In spite of the cutting by CBN tools, a dead metal occurs on the cutting edge. It acts as built up edge and roughes the cutting surface.
