CUTTING TOOL INSERT, METHOD FOR MANUFACTURING THE INSERT, AND MILLING METHOD USING THE INSERT

摘要

PROBLEM TO BE SOLVED: To provide an insert for milling to provide various wear types with excellent cutting performance during high speed cutting of an alloy steel and a tool steel and milling of a cured steel. SOLUTION: A cutting tool insert is formed of a body made of cemented carbide and a covering film and especially suitable for high speed milling for an alloy steel and a tool steel and milling for milling a cured steel. The composition of the cemented alloy body is 7.9-8.6 wt.% preferably 8.0-8.5 wt.% Co, 0.5-2.1 wt.% in a total or preferably 0.7-1.8 wt.% cubic carbide of Ta and Nb, 1.0-12.0 preferably 1.5-11.4 wt.%, average chip length 0.4-0.9μm preferably 0.5-0.8μm WC, binder phase contains W corresponding to S value 0.81-0.95 preferably 0.82-0.94. The covering film is formed of TixAlyN layer, 0.8≤x+y≤1.2, 0.25≤x/y≤1.45 preferably 0.33≤x/y≤1.1, a film thickness is 0.5-7μm preferably 1-6μm, and columnar grains are contained. COPYRIGHT: (C)2004,JPO