Abstract
In order to achieve the perfect dry cutting by end mill, firstly, a quite new nitride hard thin film was developed. And perfect dry cutting experiments of the difficult-to-cut material (SUS304) were done using various kinds of end mill to confirm the dry cutting performance of the new end mill. The kinds of end mills used in the experiments are 4 kinds, namely, non-coated (JIS : Z type cemented carbide), CrN coated, TiAlN coated and a new nitride hard thin film (this film is consists of the nitride of 3 (Al, Ti, Cr) elements. Cutting characteristics were examined based on the cutting resistance variation and the tool life under various cutting conditions. Both non-coated end mill of radial rake angle 0°and 5°and CrN coated end mill of the radial rake angle of 0°occurred the chipping of cutting edge immediately after the beginning of cutting and could not continue to cut. TiAlN coated end mill of radial rake angle of 5°could cut until 130m of real cutting distance and the new nitride coated end mill which has same radial angle could moreover continue to cut until 200m. From these results, it was suggested that the newly developed nitride hard thin film consisted of 3 elements could achieve the perfect dry cutting under the cutting condition of milling that suffers impulsive cutting resistance based on the discontinuous cutting.
