US 12,269,098 B2
Cutting tool
Susumu Okuno, Itami (JP); Takato Yamanishi, Itami (JP); Masahito Hikiji, Itami (JP); and Fumiyoshi Kobayashi, Itami (JP)
Assigned to SUMITOMO ELECTRIC HARDMETAL CORP., Itami (JP)
Appl. No. 17/924,360
Filed by Sumitomo Electric Hardmetal Corp., Itami (JP)
PCT Filed May 21, 2021, PCT No. PCT/JP2021/019381
§ 371(c)(1), (2) Date Nov. 10, 2022,
PCT Pub. No. WO2022/244243, PCT Pub. Date Nov. 24, 2022.
Prior Publication US 2024/0216997 A1, Jul. 4, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. B23B 27/14 (2006.01); C23C 16/30 (2006.01); C23C 16/32 (2006.01); C23C 16/34 (2006.01); C23C 16/36 (2006.01); C23C 16/40 (2006.01); C23C 16/56 (2006.01)
CPC B23B 27/148 (2013.01) [C23C 16/308 (2013.01); C23C 16/32 (2013.01); C23C 16/34 (2013.01); C23C 16/36 (2013.01); C23C 16/403 (2013.01); C23C 16/56 (2013.01); B23B 2228/105 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A cutting tool comprising a substrate and a coating provided on the substrate,
the coating comprising:
a first alumina layer provided on the substrate,
a titanium compound layer provided directly on the first alumina layer, and
a second alumina layer provided directly on the titanium compound layer, wherein a portion adjacent to the titanium compound layer in the first alumina layer serves as an interface region,
a portion that is not the interface region in the first alumina layer serves as a non-interface region,
a content of nitrogen in the interface region is 0.2 at % or more and 12 at % or less, and
a content of nitrogen in the non-interface region is 0 at % or more and 0.15 at % or less; and
the titanium compound layer comprises a multilayer structure layer adjacent to the first alumina layer,
the multilayer structure layer is composed of a first unit layer and a second unit layer,
the first unit layer and the second unit layer are alternately stacked in the multilayer structure layer,
the first unit layer is made of titanium carbonitride, and
the second unit layer is made of titanium carbonitroxide.