Cutting performance and failure characteristic of new cutting tool in dry milling of high-strength steel

30CrNi3MoV high-strength steel is a difficult-to-cut material which is extensive used in vehicle and aircraft. The possibility of high efficiency dry milling with cemented carbide added with TaC, NbC and Si3N4 composite ceramic is discussed based on the analysis of the material mechanical properties. The result of cutting tool wear and life shows that, the cutting tool life of 49 min and 55 min respectively is obtained within the cutting speed range of 118 to 186 m/min. The indices in the cutting tool life expressions of ceramic is bigger than that of cemented carbide, which shows that the composite ceramic is more suitable for the face milling of 30CrNi3MoV high-strength steel in the high speed range. The main wear form is the long irregular wear land in flank face, crater in the middle of the chamfer, as well as sector peeling in rake face and triangular breakage in the corner due to the high cutting temperature and the periodical mechanical shock. (4 pages)