US 11,919,092 B2
Cutting tool
Yasuki Kido, Itami (JP); Anongsack Paseuth, Itami (JP); Susumu Okuno, Itami (JP); and Shinya Imamura, Itami (JP)
Assigned to SUMITOMO ELECTRIC HARDMETAL CORP., Itami (JP)
Appl. No. 17/291,282
Filed by Sumitomo Electric Hardmetal Corp., Itami (JP)
PCT Filed Feb. 27, 2020, PCT No. PCT/JP2020/008144
§ 371(c)(1), (2) Date May 5, 2021,
PCT Pub. No. WO2020/213260, PCT Pub. Date Oct. 22, 2020.
Claims priority of application No. 2019-078672 (JP), filed on Apr. 17, 2019.
Prior Publication US 2022/0001456 A1, Jan. 6, 2022
Int. Cl. B23B 27/14 (2006.01); B23C 5/16 (2006.01)
CPC B23B 27/148 (2013.01) [B23C 5/16 (2013.01); B23B 2222/04 (2013.01); B23B 2222/88 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A cutting tool including a rake face, a flank face, and a cutting edge portion connecting the rake face and the flank face together,
the cutting tool comprising a substrate and an AlTiN layer provided on the substrate,
the AlTiN layer including cubic AlxTi1-xN crystal grains,
an atomic ratio x of Al in the cubic AlxTi1-xN crystal grains being 0.7 or more and 0.95 or less on each of the rake face, the flank face and the cutting edge portion,
the AlTiN layer including a central portion,
the central portion of the AlTiN layer being a region sandwiched between a first imaginary plane and a second imaginary plane, the first imaginary plane being an imaginary plane which passes through a point 1 μm away in a direction of thickness from a first interface located on a side of the substrate and is parallel to the first interface, the second imaginary plane being an imaginary plane which passes through a point 1 μm away from a second interface opposite to the side of the substrate in the direction of thickness and is parallel to the second interface,
the first interface being parallel to the second interface,
the central portion of the AlTiN layer at the rake face being occupied in area at a ratio of 80% or more by first cubic AlxTi1-xN crystal grains having a (200) plane with a normal thereto having a direction within ±15° with respect to a direction of a normal to the second interface at the rake face,
the central portion of the AlTiN layer at the flank face being occupied in area at a ratio of 80% or more by second cubic AlxTi1-xN crystal grains having a (200) plane with a normal thereto having a direction within ±15° with respect to a direction of a normal to the second interface at the flank face,
the central portion of the AlTiN layer at the cutting edge portion being occupied in area at a ratio of 80% or more by third cubic AlxTi1-xN crystal grains having a (200) plane with a normal thereto having a direction within ±15° with respect to a direction of a normal to the cutting edge portion,
the direction of the normal to the cutting edge portion being a direction of a normal to a third imaginary plane including a boundary line on the substrate between the rake face and the cutting edge portion and a boundary line on the substrate between the flank face and the cutting edge portion.