Split Cutter Method for Contact Stresses Research over Flank Surface of a Cutter

Abstract

The paper presents a method for of contact load (stress) research over a flank land of a cutter by a “split cutter” (sectional cutter) method which is more preferable in cutting steels and durable materials in industrial cutting mode. The research of contact stresses distribution over surfaces of a cutter must be carried out on the special rigid four-component dynamometer for the “split cutter” with inspection of total components of cutting force Pz and Py. However, the investigation of contact loads distribution over the flank land faces the problem due to elastic deformation of measuring elements and penetration of work material into a slit between the two parts of the “split cutter”. The research of contact stresses distribution over a face of a cutter should be carried out on a lathe with horizontal radial feed, while the research of contact stresses distribution over a flank land should be done on a horizontal-milling machine with vertical radial feed of a table. The distributions of contact stresses over the flank land of the cutter in free orthogonal turning of a disk made from ductile brass (63Cu-37Zn), brittle brass (57Cu-39Zn-1Al-3Mn) are described. In machining ductile brass with formation of a continuous chip, extreme pattern of normal σh and tangential τh contact stresses epures (curves of distribution) over a flank land is observed, i.e. the highest contact stress is at some distance from the cutting edge. In machining brittle brass with formation of a discontinuous chip, the highest contact stress is observed, on the contrary, near the cutting edge. The character of normal contact stresses over a flank-land depends on the type of the chip formation due to a sag of the transient surface under the act of a radial component of the cutting force on the rake surface.