SUMITOMO ELECTRIC HARDMETAL CORP.

A cutting tool comprising a base material and a coating; wherein: the coating comprises a titanium compound layer and an α-Al 2 O 3 layer; the α-Al 2 O 3 layer comprises a region A 1 and a region A 2 ; the titanium compound layer comprises a region B 1 and a region B 2 ; an average particle diameter a1 of the α-Al 2 O 3 particles in the region A 1 , an average particle diameter a2 of the α-Al 2 O 3 particles in the region A 2 , an average particle diameter b1 of the titanium compound particles in the region B 1 , and an average particle diameter b2 of the titanium compound particles in the region B 2 satisfy relationships represented by respective expressions 1 to 3: 0.80≤ a 2/ b 2≤1.27  Expression 1 1.50≤ a 1/ a 2≤10  Expression 2 1.45≤ b 1/ b 2≤5  Expression 3 ; and the average particle diameter b1 is 0.10 μm or more and 0.50 μm or less.

Provided is a machining condition determination support device that supports determination of a machining condition for a machine tool that machines a workpiece with a tool. The device includes: a determination unit configured to, based on target shape information indicating a shape of the workpiece, path information indicating a movement path of the tool, and tool shape information indicating a shape of the tool, determine a contact position between the tool and the workpiece when the tool moves along the movement path; and a first generation unit configured to generate contact position information indicating temporal transition of the contact position when the tool moves along the movement path.

A cutting insert includes: a rake face; a flank face; and a cutting edge constituted of a ridgeline between the rake face and the flank face. The cutting edge has a first cutting edge portion for corner processing, a second cutting edge portion for pulling processing, a third cutting edge portion for finished-surface processing, a first connection cutting edge portion, and a second connection cutting edge portion. The third cutting edge portion is disposed between the first cutting edge portion and the second cutting edge portion. The first cutting edge portion has a curved shape. A curvature radius of the first cutting edge portion is 0.1 mm or more and 2.4 mm or less. The second cutting edge portion has a straight line shape or a curved shape having a curvature radius of 3 mm or more.

A cutting tool includes: a substrate; and a coating film including a first layer and a second layer, the first layer consists of a multilayer structure consisting of a first unit layer composed of Ti a Al 1-a-b B b N, and the second unit layer composed of TiN, where 0.30≤a≤0.50 and 0.005≤b≤0.10, the second layer is composed of TiC x N 1-x , where 0.05≤x≤0.40, the second layer includes a first region and a second region, in the first region, an average C1 of percentages of the numbers of carbon atoms with respect to totals of the numbers of the carbon atoms and the numbers of nitrogen atoms is 25% or more and 50% or less, in the second region, an average C2 of percentages of the numbers of carbon atoms with respect to totals of the numbers of the carbon atoms and the numbers of nitrogen atoms is 1% or more and 10% or less.