JP2014184522A - Surface-coated wc-based super hard alloy-made cutting tool with hard coating layer exhibiting superior adhesiveness - Google Patents

Surface-coated wc-based super hard alloy-made cutting tool with hard coating layer exhibiting superior adhesiveness Download PDF

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JP2014184522A
JP2014184522A JP2013061377A JP2013061377A JP2014184522A JP 2014184522 A JP2014184522 A JP 2014184522A JP 2013061377 A JP2013061377 A JP 2013061377A JP 2013061377 A JP2013061377 A JP 2013061377A JP 2014184522 A JP2014184522 A JP 2014184522A
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Akira Motohana
章 素花
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Mitsubishi Materials Corp
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Abstract

PROBLEM TO BE SOLVED: To provide a surface-coated WC-based super hard alloy- made cutting tool in which a hard coating layer exerts superior peeling resistance and wear resistance in high speed-high feed cutting of a steel, cast iron or the like.SOLUTION: There is provided surface-coated WC-based super hard alloy-made cutting tool containing WC, further at least a Ti component as a hard phase component, and Co as a coupling phase. A hard coating layer comprises a first layer (modified AlN layer) coated on the surface of a tool substrate, a second layer (TiAlC layer or TiAlCN layer) coated on the surface of the first layer, and a third layer (AlOlayer) according to needs. In the first layer, W, Co and Ti are included by dispersion from the tool substrate. The W content of the boundary of a tool substrate side is 2.2 to 7.8 atom%, the Co content 1.2 to 4.2 atom% and the Ti content 2.4 to 9.6 atom%. Every content of W, Co and Ti in the first layer exhibits such a composition inclined structure as reducing gradually as moving from the tool substrate side to the second layer side.

Description

この発明は、鋼や鋳鉄を高速高送り切削加工した場合でも、耐剥離性にすぐれ、長期の使用にわたってすぐれた耐摩耗性と耐欠損性を発揮する表面被覆WC基超硬合金製切削工具(以下、被覆超硬工具という)に関するものである。   This invention is a cutting tool made of a surface-coated WC-based cemented carbide that has excellent peeling resistance and excellent wear resistance and fracture resistance over a long period of use even when steel or cast iron is processed at high speed and high feed. Hereinafter, it is related to a coated carbide tool.

従来、鋼や鋳鉄の切削加工用工具としては、例えば、特許文献1に示されるように、WC基超硬合金を工具基体とし、その表面に、Tiの炭化物、窒化物、炭窒化物、炭酸化物、窒酸化物および炭窒酸化物のうち一種またはそれ以上の層、また、必要に応じて、4a,5a,6a族の炭化物、窒化物、酸化物、硼化物およびこれらの固溶体もしくは化合物並びに酸化アルミニウムから選ばれる一種もしくはそれ以上からなる単層または複層を被覆形成した被覆超硬工具が知られている。
従来の被覆超硬工具においては、高速重切削加工において切刃に作用する高負荷の切削条件に対応するため、工具の靭性向上、耐摩耗性向上とともに、硬質被覆層の耐剥離性向上が求められており、このような課題を解決すべく、種々の提案がなされている。
Conventionally, as a tool for cutting steel or cast iron, for example, as shown in Patent Document 1, a WC-based cemented carbide is used as a tool base, and Ti carbide, nitride, carbonitride, carbonic acid is formed on the surface thereof. One or more layers of nitrides, nitrides and carbonitrides, and optionally 4a, 5a, 6a group carbides, nitrides, oxides, borides and solid solutions or compounds thereof, and A coated cemented carbide tool in which a single layer or multiple layers selected from aluminum oxide is coated is known.
In conventional coated carbide tools, it is necessary to improve the toughness and wear resistance of the tool and improve the peel resistance of the hard coating layer in order to cope with the high-load cutting conditions that act on the cutting edge in high-speed heavy cutting. Various proposals have been made to solve such problems.

例えば、特許文献2に示すように、結合相形成成分としてCo:5〜25重量%を含有する炭化タングステン基超硬合金基体の表面に3層からなる硬質被覆層を構成し、かつ上記基体に接する第1層を平均層厚:0.1〜1μmの炭化チタン層、第2層を同4〜10μmの炭窒化チタン層、および第3層を同1〜2μmの酸化アルミニウム層とすると共に、前記第1層および第2層中に、基体を構成するWおよびCo成分を拡散含有させることによって、高送りおよび高切込みなどの重切削における耐チッピング性、耐欠損性を改善することが提案されている。   For example, as shown in Patent Document 2, a hard coating layer composed of three layers is formed on the surface of a tungsten carbide base cemented carbide substrate containing Co: 5 to 25% by weight as a binder phase forming component, and The first layer in contact is an average layer thickness: 0.1-1 μm titanium carbide layer, the second layer is the same 4-10 μm titanium carbonitride layer, and the third layer is the same 1-2 μm aluminum oxide layer, It has been proposed to improve the chipping resistance and fracture resistance in heavy cutting such as high feed and high cutting by diffusing and containing W and Co components constituting the base in the first layer and the second layer. ing.

また、例えば、特許文献3に示すように、超硬合金基体の表面に、CVD法によって、Ti1−XAlN層、Ti1−XAlC層およびTi1−XAlCN層(式中、Xは0.65〜0.95である)の少なくとも一つの層を被覆形成し、この上にAl層を外層として被覆形成することによって、硬質被覆層の断熱性、亀裂抵抗性を改善することが提案されている。 For example, as shown in Patent Document 3, a Ti 1-X Al X N layer, a Ti 1-X Al X C layer, and a Ti 1-X Al X CN layer are formed on the surface of a cemented carbide substrate by a CVD method. (Wherein X is 0.65 to 0.95), and heat-insulating the hard coating layer by coating the Al 2 O 3 layer as an outer layer thereon, It has been proposed to improve crack resistance.

特開昭58−55560号公報JP 58-55560 A 特開平7−243023号公報Japanese Patent Application Laid-Open No. 7-243023 特表2011−516722号公報Special table 2011-516722 gazette

近年の切削加工の高性能化はめざましく、一方で切削加工に対する省力化および省エネ化、さらに低コスト化の要求が強く、これに伴い、切削加工は一段と高速化の傾向にあるが、特許文献1〜3に示す従来被覆超硬工具においては、これを通常の条件下で使用した場合には特段の問題は生じないが、例えば鋼や鋳鉄の高速高送り切削加工に供した場合には、高熱発生とともに、切刃に作用する高負荷によって、硬質被覆層の剥離、欠損等の異常損傷が発生し易く、この結果、比較的短時間で使用寿命に至るのが現状である。   In recent years, there has been a remarkable increase in performance of cutting work, while there is a strong demand for labor saving and energy saving and further cost reduction for cutting work. With this, cutting work tends to be further speeded up. In the conventional coated cemented carbide tools shown in No. 3 to 3), there is no particular problem when used under normal conditions. For example, when used for high-speed high-feed cutting of steel or cast iron, Along with the occurrence, abnormal loads such as peeling and chipping of the hard coating layer are likely to occur due to the high load acting on the cutting edge, and as a result, the service life is reached in a relatively short time.

そこで本発明者等は、上述のような観点から、高熱発生を伴い、切刃に高負荷が作用する鋼や鋳鉄の高速高送り切削加工に供した場合でも、硬質被覆層が欠損、剥離等の異常損傷を発生することなく、長期の使用に亘ってすぐれた耐摩耗性を発揮する被覆超硬工具について鋭意研究したところ、以下の知見を得た。   In view of the above, the present inventors have found that the hard coating layer is damaged, peeled off, etc., even when subjected to high-speed high-feed cutting of steel or cast iron that is accompanied by high heat generation and a high load acts on the cutting blade, from the above viewpoint. As a result of earnest research on coated carbide tools that exhibit excellent wear resistance over a long period of time without causing abnormal damage, the following findings were obtained.

すなわち、少なくともTiをその成分として含有するWC基超硬合金を工具基体とし、第1層としてのAlの窒化物(以下、「AlN」で示す)層、また、第2層としてのTiとAlの複合炭化物(以下、「TiAlC」で示す)層またはTiとAlの複合炭窒化物(以下、「TiAlCN」で示す)層、さらに、必要により、第3層としての酸化アルミニウム(以下、「Al」で示す)層からなる硬質被覆層を化学蒸着法で被覆形成するにあたり、第1層を形成した後、1100〜1250℃で熱処理を行い、第1層を、所定量のW、CoおよびTiが濃度勾配を形成するように含有せしめた改質層とすることによって、工具基体と硬質被覆層間の密着性が向上し、高熱発生を伴い、切刃に高負荷が作用する鋼や鋳鉄の高速高送り切削加工において、欠損、剥離等の異常損傷を発生することなく、長期の使用に亘ってすぐれた耐摩耗性を発揮するようになることを見出したのである。 That is, a WC-based cemented carbide containing at least Ti as a component thereof is used as a tool base, an Al nitride (hereinafter referred to as “AlN”) layer as a first layer, and Ti and Al as a second layer Composite carbide (hereinafter referred to as “TiAlC”) layer, Ti and Al composite carbonitride (hereinafter referred to as “TiAlCN”) layer, and, if necessary, aluminum oxide (hereinafter referred to as “Al”) as a third layer. In forming a hard coating layer composed of a layer represented by 2 O 3 ) by chemical vapor deposition, after forming the first layer, heat treatment is performed at 1100 to 1250 ° C., and the first layer is subjected to a predetermined amount of W, By adopting a modified layer containing Co and Ti so as to form a concentration gradient, the adhesion between the tool base and the hard coating layer is improved, high heat is generated, and a high load acts on the cutting blade. High speed high feed of cast iron It has been found that in cutting work, excellent wear resistance can be exhibited over a long period of use without causing abnormal damage such as chipping and peeling.

本発明は、上記知見に基づいてなされたものであって、
「(1) 硬質相成分としてWCを含有し、さらに、少なくともTi成分を含有するとともに、結合相成分としてCoを含有するWC基超硬合金を工具基体とし、該工具基体表面に、硬質被覆層を化学蒸着で被覆形成した表面被覆WC基超硬合金製切削工具において、
(a)上記硬質被覆層は、工具基体表面に被覆された第1層と、第1層の表面に被覆された第2層からなり、
(b)第1層は、0.5〜2μmの平均層厚を有するAlの窒化物を主体とする改質層、また、第2層は、2〜10μmの平均層厚を有するTiとAlの複合炭化物層またはTiとAlの複合炭窒化物層からなり、
(c)上記第1層中には、工具基体からの拡散によってW、CoおよびTiが含有され、第1層中における工具基体側界面のW含有量は2.2原子%以上7.8原子%以下、Co含有量は1.2原子%以上4.2原子%以下、Ti含有量は2.4原子%以上9.6原子%以下であり、
(d)上記第1層中におけるW含有量、Co含有量およびTi含有量は、いずれも、工具基体側から第2層側へ行くにしたがい、次第に減少している組成傾斜構造を示すことを特徴とする表面被覆WC基超硬合金製切削工具。
(2) 上記表面被覆WC基超硬合金製切削工具において、上記第2層の表面に、さらに、3〜10μmの平均層厚のAl層からなる第3層を化学蒸着により被覆形成したことを特徴とする前記(1)に記載の表面被覆WC基超硬合金製切削工具。」
を特徴とするものである。
The present invention has been made based on the above findings,
“(1) A WC-based cemented carbide containing WC as a hard phase component and further containing at least a Ti component and Co as a binder phase component is used as a tool base, and a hard coating layer is formed on the surface of the tool base. In a surface-coated WC-based cemented carbide cutting tool coated with chemical vapor deposition,
(A) The hard coating layer includes a first layer coated on the surface of the tool base and a second layer coated on the surface of the first layer,
(B) The first layer is a modified layer mainly composed of Al nitride having an average layer thickness of 0.5 to 2 μm, and the second layer is Ti and Al having an average layer thickness of 2 to 10 μm. A composite carbide layer of Ti or Al and a composite carbonitride layer of Ti and Al,
(C) The first layer contains W, Co, and Ti by diffusion from the tool base, and the W content at the tool base side interface in the first layer is 2.2 atomic% or more and 7.8 atoms. %, Co content is 1.2 atomic% or more and 4.2 atomic% or less, Ti content is 2.4 atomic% or more and 9.6 atomic% or less,
(D) The W content, the Co content, and the Ti content in the first layer all indicate a composition gradient structure that gradually decreases from the tool base side to the second layer side. A surface-coated WC-based cemented carbide cutting tool.
(2) In the surface-coated WC-based cemented carbide cutting tool, a third layer made of Al 2 O 3 having an average layer thickness of 3 to 10 μm is formed on the surface of the second layer by chemical vapor deposition. The surface-coated WC-based cemented carbide cutting tool according to (1) above, wherein "
It is characterized by.

次に、この発明の被覆超硬工具について説明する。   Next, the coated carbide tool of the present invention will be described.

(a)WC基超硬合金からなる工具基体
本発明の被覆超硬工具の工具基体を構成するWC基超硬合金は、WCを硬質相成分の主体として含有するが、この他に、少なくとも、Ti(例えば、炭化物、窒化物、炭窒化物等として)成分をさらに含有する。
Ti成分は後記するように、硬質被覆層の第1層に拡散し、かつ、工具基体側から第2層側へ行くにしたがい、次第にTi含有割合が減少するような濃度分布を形成する。
WC基超硬合金の硬質相成分であるTiの含有は、母材強度、高温硬度、耐摩耗性の向上に効果があるが、多量に含有した場合には、強度低下を招く恐れがあるが、その一方、硬質被覆層の第1層に拡散含有させる必要があることから、WC基超硬合金中におけるTi成分の含有量は3〜15質量%とすることが望ましい。
(A) Tool substrate made of WC-based cemented carbide The WC-based cemented carbide constituting the tool substrate of the coated cemented carbide tool of the present invention contains WC as a main component of the hard phase component. It further contains a Ti component (eg, as carbide, nitride, carbonitride, etc.).
As will be described later, the Ti component diffuses into the first layer of the hard coating layer, and forms a concentration distribution in which the Ti content ratio gradually decreases as it goes from the tool base side to the second layer side.
Inclusion of Ti, which is a hard phase component of a WC-based cemented carbide, is effective in improving the base material strength, high-temperature hardness, and wear resistance. On the other hand, the content of the Ti component in the WC-based cemented carbide is preferably 3 to 15% by mass because it is necessary to diffuse and contain it in the first layer of the hard coating layer.

本発明の被覆超硬工具の工具基体を構成するWC基超硬合金は、結合相形成成分として、少なくともCoを含有する。
Co成分には、結合相を形成して基体の強度および靭性を向上させる作用があるが、WC基超硬合金中の平均Co含有量が5質量%未満では、特に靭性に所望の向上効果が得られず、さらに、硬質被覆層の第1層中に拡散する量も少なくなり、一方、平均Co含有量が15質量%を越えると、塑性変形が起り易くなって、偏摩耗の進行が促進されるようになることから、WC基超硬合金中の平均Co含有量は5〜15質量%とすることが望ましい。
The WC-based cemented carbide constituting the tool base of the coated cemented carbide tool of the present invention contains at least Co as a binder phase forming component.
The Co component has an action of improving the strength and toughness of the substrate by forming a binder phase. However, when the average Co content in the WC-based cemented carbide is less than 5% by mass, the desired improvement effect is particularly exerted on the toughness. In addition, the amount of diffusion into the first layer of the hard coating layer is reduced. On the other hand, if the average Co content exceeds 15% by mass, plastic deformation tends to occur and the progress of uneven wear is promoted. Therefore, the average Co content in the WC-based cemented carbide is preferably 5 to 15% by mass.

(b)第1層(AlNを主体とする改質層)
WC基超硬合金からなる工具基体表面に形成されるAlNを主体とする改質層(第1層。以下、場合により、「改質AlN層」ともいう)は、Alの窒化物を主体とするが、後記する化学蒸着後の熱処理における拡散によって、WC基超硬合金の成分であるW、CoおよびTiを含有する。
改質AlN層中において、WC基超硬合金からの拡散によって含有される工具基体側界面のW含有量は2.2原子%以上7.8原子%以下、Co含有量は1.2原子%以上4.2原子%以下、Ti含有量は2.4原子%以上9.6原子%以下であることが必要である。
改質AlN層中に含有されるW含有量およびCo含有量が、それぞれの上限値を超えると、改質AlN層中に異相が形成され耐摩耗性が著しく低下するようになるためであり、また、Ti含有量が9.6原子%を超えるようになると改質AlN層中におけるTi含有量の濃度勾配が大きくなりすぎ、改質AlN層の形成が不均一となり、膜性能にバラツキが生じるため、工具基体側界面の改質AlN層中におけるTi含有量は9.6原子%以下であることが必要である。
一方、工具基体側界面の改質AlN層中に含有されるW、Co、Ti含有量がそれぞれの下限を下回るようになると、工具基体と改質AlN層との密着性向上効果が現れないことから、W含有量、Co含有量、Ti含有量の下限は、それぞれ、2.2原子%、1.2原子%、2.4原子%とすることが必要である。
また、W、Co、Tiのいずれもが、WC基超硬合金からの拡散によって改質AlN層中に含有されるものであるから、工具基体側から第2層側へ行くにしたがい、W、Co、Tiのいずれもが、次第にその含有量が減少する組成傾斜構造を示すようになる。
本発明の改質AlN層(第1層)は、AlNを主体とする層であることによって、該層中へのTi成分の拡散を促進し、また、上記の如きW、Co、Tiの組成傾斜構造を示すことによって、改質AlN層(第1層)は靭性が向上する。さらに、WC基超硬合金からなる工具基体表面と強固な密着性を有し、また、TiAlC層またはTiAlCN層からなる第2層との密着性にもすぐれ、その結果、高熱発生を伴い、切刃に高負荷が作用する鋼や鋳鉄の高速高送り切削加工において、欠損、剥離等の異常損傷を発生することなく、長期の使用に亘ってすぐれた耐摩耗性を発揮する。
(B) First layer (modified layer mainly composed of AlN)
A modified layer mainly composed of AlN formed on the surface of a tool base made of a WC-based cemented carbide (first layer; hereinafter also referred to as “modified AlN layer” in some cases) is composed mainly of Al nitride. However, it contains W, Co, and Ti, which are components of the WC-based cemented carbide, by diffusion in the heat treatment after chemical vapor deposition described later.
In the modified AlN layer, the W content at the tool base side interface contained by diffusion from the WC-based cemented carbide is 2.2 atomic% to 7.8 atomic%, and the Co content is 1.2 atomic%. It is necessary that the content is 4.2 atomic percent or less and the Ti content is 2.4 atomic percent or more and 9.6 atomic percent or less.
This is because when the W content and the Co content contained in the modified AlN layer exceed the respective upper limit values, a different phase is formed in the modified AlN layer and the wear resistance is significantly reduced. Further, when the Ti content exceeds 9.6 atomic%, the concentration gradient of Ti content in the modified AlN layer becomes too large, and the formation of the modified AlN layer becomes non-uniform, resulting in variations in film performance. Therefore, the Ti content in the modified AlN layer at the tool base side interface needs to be 9.6 atomic% or less.
On the other hand, if the contents of W, Co, and Ti contained in the modified AlN layer on the tool base side interface are lower than the respective lower limits, the effect of improving the adhesion between the tool base and the modified AlN layer does not appear. Therefore, the lower limits of the W content, the Co content, and the Ti content must be 2.2 atomic%, 1.2 atomic%, and 2.4 atomic%, respectively.
Further, since all of W, Co, and Ti are contained in the modified AlN layer by diffusion from the WC-based cemented carbide, as W goes from the tool base side to the second layer side, W, Both Co and Ti exhibit a composition gradient structure in which the content gradually decreases.
The modified AlN layer (first layer) of the present invention is a layer mainly composed of AlN, thereby promoting the diffusion of Ti component into the layer, and the composition of W, Co, and Ti as described above. By showing the inclined structure, the toughness of the modified AlN layer (first layer) is improved. Furthermore, it has strong adhesion to the surface of the tool base made of WC-based cemented carbide, and also has excellent adhesion to the second layer made of TiAlC layer or TiAlCN layer. In high-speed, high-feed cutting of steel or cast iron where a high load acts on the blade, it exhibits excellent wear resistance over a long period of use without causing abnormal damage such as chipping or peeling.

(c)第2層(TiAlC層またはTiAlCN層)
第1層の表面に化学蒸着で形成するTiAlC層またはTiAlCN層は、いずれも熱伝導率が低く断熱性にすぐれるとともに、亀裂抵抗性が高いことから、高熱発生を伴い、切刃に高負荷が作用する鋼や鋳鉄の高速高送り切削加工において、欠損、剥離等の異常損傷の発生が抑制される。
TiAlC層、TiAlCN層を、それぞれ、
組成式:(Ti1−YAl)C、
組成式:(Ti1−ZAl)CN、
で表した場合、0.7≦Y又はZ≦0.95、(但し、Y、Zは原子比)であることが望ましい。これは、Y、Zの値が0.7未満であると、膜の断熱性および亀裂抵抗性が低下し、一方、Y、Zの値が0.95を超えると、膜硬度が低下することから、Y、Zの値は、0.7≦Y又はZ≦0.95(但し、Y、Zは原子比)であることが望ましい。
(C) Second layer (TiAlC layer or TiAlCN layer)
The TiAlC layer or TiAlCN layer formed by chemical vapor deposition on the surface of the first layer has both low thermal conductivity and excellent heat insulation properties, and high crack resistance. In high-speed, high-feed cutting of steel or cast iron on which cracking occurs, the occurrence of abnormal damage such as chipping and peeling is suppressed.
TiAlC layer, TiAlCN layer,
Composition formula: (Ti 1-Y Al Y ) C,
Formula: (Ti 1-Z Al Z ) CN,
It is preferable that 0.7 ≦ Y or Z ≦ 0.95 (where Y and Z are atomic ratios). This is because when the values of Y and Z are less than 0.7, the heat insulation and crack resistance of the film are lowered, and when the values of Y and Z are more than 0.95, the film hardness is lowered. Therefore, the values of Y and Z are preferably 0.7 ≦ Y or Z ≦ 0.95 (where Y and Z are atomic ratios).

(d)第3層(Al層)
Al層からなる第3層は、必要に応じ、第2層の表面に当業者に良く知られた通常の化学蒸着法によって形成することができる。
Al層は、よく知られているように、すぐれた硬さ、耐熱性、耐摩耗性を有し、被覆超硬工具の長寿命化を図ることができる。
第3層の平均層厚が、3μm未満であると第3層を形成したことの効果が十分に発揮できず、一方、その平均層厚が10μmを超えると、耐チッピング性、耐欠損性が低下傾向を示すことから、第3層を形成する場合、その平均層厚は3〜10μmとすることが望ましい。
(D) Third layer (Al 2 O 3 layer)
The third layer composed of the Al 2 O 3 layer can be formed on the surface of the second layer by a normal chemical vapor deposition method well known to those skilled in the art, if necessary.
As is well known, the Al 2 O 3 layer has excellent hardness, heat resistance, and wear resistance, and can extend the life of the coated carbide tool.
If the average layer thickness of the third layer is less than 3 μm, the effect of forming the third layer cannot be sufficiently exhibited. On the other hand, if the average layer thickness exceeds 10 μm, chipping resistance and fracture resistance are Since a decreasing tendency is shown, when the third layer is formed, the average layer thickness is preferably 3 to 10 μm.

(e)被覆超硬工具の製造
本発明の被覆超硬工具は、例えば、以下の手順で製造することができる。
(E) Production of coated carbide tool The coated carbide tool of the present invention can be produced, for example, by the following procedure.

(イ)まず、WCを硬質相成分の主体として含有し、また、少なくとも、Ti成分を含有し、さらに、Coを結合相成分とするWC基超硬合金基体表面に、
例えば、通常の化学蒸着装置を用い、
反応ガス組成(容量%):AlCl 5〜15%、残りN
反応雰囲気温度:950〜1050℃、
反応雰囲気圧力:12〜20kPa、
の条件でAlN層からなる下地層を、所定の層厚(0.5〜2μm)で蒸着形成する。
(A) First, WC is contained as a main component of the hard phase component, and at least a Ti component is contained, and further, on the surface of the WC-based cemented carbide substrate having Co as a binder phase component,
For example, using normal chemical vapor deposition equipment,
Reaction gas composition (volume%): AlCl 3 5-15%, remaining N 2 ,
Reaction atmosphere temperature: 950 to 1050 ° C.
Reaction atmosphere pressure: 12-20 kPa,
Under the conditions, an underlayer composed of an AlN layer is formed by vapor deposition with a predetermined layer thickness (0.5 to 2 μm).

(ロ)ついで、上記(イ)で、下地層を蒸着形成したWC基超硬合金を、
熱処理雰囲気:Ar 100%
熱処理温度:1100〜1250℃
熱処理時間:90〜240分
の条件で熱処理を行い、WC基超硬合金の成分であるW、Co、Tiを下地層中に拡散させることにより、下地層を改質AlN層に改質する。
なお、改質AlN層中におけるW、Co、Tiの含有量、組成傾斜構造は、上記熱処理条件、特に、熱処理温度と熱処理時間によって調整することができる。
例えば、熱処理温度1100℃、熱処理時間90分の場合には、工具基体側界面の改質AlN層中のW、Co、Ti含有量は、それぞれ、2.2原子%、1.2原子%、4.2原子%となり、一方、熱処理温度1250℃、熱処理時間240分の場合には、工具基体側界面の改質AlN層中のW、Co、Ti含有量は、それぞれ、4.3原子%、2.8原子%、5.1原子%となる。
(B) Next, in the above (a), the WC-based cemented carbide in which the underlayer is formed by vapor deposition,
Heat treatment atmosphere: Ar 100%
Heat treatment temperature: 1100-1250 ° C
Heat treatment time: Heat treatment is performed under conditions of 90 to 240 minutes, and W, Co, and Ti, which are components of the WC-base cemented carbide, are diffused into the underlayer, thereby modifying the underlayer into a modified AlN layer.
The content of W, Co, Ti and the composition gradient structure in the modified AlN layer can be adjusted by the above heat treatment conditions, in particular, the heat treatment temperature and the heat treatment time.
For example, when the heat treatment temperature is 1100 ° C. and the heat treatment time is 90 minutes, the W, Co, and Ti contents in the modified AlN layer on the tool base side interface are 2.2 atomic% and 1.2 atomic%, respectively. On the other hand, when the heat treatment temperature is 1250 ° C. and the heat treatment time is 240 minutes, the contents of W, Co, and Ti in the modified AlN layer on the tool base side interface are 4.3 atom%, respectively. 2.8 atomic% and 5.1 atomic%.

(ハ)ついで、通常の化学蒸着装置を用い、
反応ガス組成(容量%):TiCl 0.1〜2.0%、AlCl 0.5〜2.8%、NH 1.2〜4.8%、CH1.8〜6.6%、N0〜15.5%、残りH
反応雰囲気温度:750〜900℃、
反応雰囲気圧力:1〜4kPa、
の条件でTiAlC層あるいはTiAlCN層からなる第2層を、所定の層厚(2〜10μm)で蒸着形成する。
上記(イ)〜(ハ)で作製した被覆超硬工具は、鋼や鋳鉄の高速高送り切削加工に供した場合には、欠損、剥離等の異常損傷を発生することなく、すぐれた耐摩耗性を発揮する。
(C) Next, using a normal chemical vapor deposition system,
Reaction gas composition (volume%): TiCl 4 0.1 to 2.0%, AlCl 3 0.5 to 2.8%, NH 3 1.2 to 4.8%, CH 4 1.8 to 6.6 %, N 2 0 to 15.5%, remaining H 2
Reaction atmosphere temperature: 750 to 900 ° C.
Reaction atmosphere pressure: 1-4 kPa,
A second layer made of a TiAlC layer or a TiAlCN layer is formed by vapor deposition with a predetermined layer thickness (2 to 10 μm) under the conditions described above.
The coated carbide tools produced in (a) to (c) above have excellent wear resistance without causing abnormal damage such as chipping or peeling when subjected to high-speed high-feed cutting of steel or cast iron. Demonstrate sex.

(ニ)(イ)〜(ハ)で被覆超硬工具を作製した後、第3層として3〜10μmのAl層を蒸着形成することによって、一段と耐摩耗性を高めることができ、被覆超硬工具のより一層の長寿命化を図ることができる。 (D) After producing the coated carbide tool in (i) to (c), the wear resistance can be further improved by forming a 3 to 10 μm Al 2 O 3 layer as the third layer by vapor deposition. The service life of the coated carbide tool can be further increased.

本発明の被覆超硬工具によれば、密着性にすぐれた改質AlN層が工具基体表面に形成されていることから、高熱発生を伴い、切刃に高負荷が作用する鋼や鋳鉄の高速高送り切削加工において、欠損、剥離等の異常損傷を発生することなく、長期の使用に亘ってすぐれた耐摩耗性を発揮することができるのである。   According to the coated carbide tool of the present invention, since the modified AlN layer with excellent adhesion is formed on the surface of the tool base, high-speed production of steel or cast iron that causes high heat generation and a high load acts on the cutting edge. In high-feed cutting, excellent wear resistance can be exhibited over a long period of use without causing abnormal damage such as chipping and peeling.

次に、本発明の表面被覆WC基超硬合金製切削工具(被覆超硬工具)について、実施例により具体的に説明する。   Next, the surface-coated WC-based cemented carbide cutting tool (coated cemented carbide tool) of the present invention will be specifically described with reference to examples.

(a) 原料粉末として、いずれも0.5〜3μmの平均粒径を有するWC粉末、TiC粉末、TiN粉末、TaC粉末、NbC粉末、Cr粉末およびCo粉末を、表1に示す割合に配合し、さらにワックスを加えてアセトン中で72時間ボールミル混合し、減圧乾燥した後、100MPaの圧力で所定形状の圧粉体にプレス成形した。
このプレス成形により得た圧粉体を、6Paの真空中、1400℃にて1時間保持の条件で真空焼結して焼結体を作製し、WC基超硬合金1〜5を製造した。
これらのWC基超硬合金1〜4に、R:0.07mmのホーニング加工を施すことにより、ISO・CNMG120408に規定されるインサート形状をもった工具基体1〜4を製造した。
(A) The ratio of WC powder, TiC powder, TiN powder, TaC powder, NbC powder, Cr 3 C 2 powder and Co powder each having an average particle diameter of 0.5 to 3 μm as raw material powders as shown in Table 1 The mixture was further mixed with wax, ball milled in acetone for 72 hours, dried under reduced pressure, and pressed into a green compact of a predetermined shape at a pressure of 100 MPa.
The green compact obtained by this press molding was vacuum sintered in a 6 Pa vacuum at 1400 ° C. for 1 hour to produce a sintered body, and WC-based cemented carbides 1 to 5 were produced.
By applying honing of R: 0.07 mm to these WC-based cemented carbides 1 to 4, tool bases 1 to 4 having an insert shape defined in ISO · CNMG120408 were manufactured.

(b) ついで、表2に示す下地層の化学蒸着条件で、工具基体1〜4の表面に表4に示す目標平均層厚のAlN層を形成した。 (B) Next, an AlN layer having a target average layer thickness shown in Table 4 was formed on the surfaces of the tool bases 1 to 4 under the chemical vapor deposition conditions of the underlayer shown in Table 2.

(d) ついで、下地層を化学蒸着で被覆形成した上記本発明工具基体1〜4を、熱処理炉に装入し、表3に示す本発明熱処理条件で熱処理を施し、表4に示す目標平均層厚の改質AlN層として改質形成した。 (D) Next, the above-mentioned tool bases 1 to 4 according to the present invention in which the base layer was formed by chemical vapor deposition were placed in a heat treatment furnace, subjected to heat treatment under the heat treatment conditions of the present invention shown in Table 3, and the target average shown in Table 4 A modified AlN layer having a layer thickness was modified and formed.

(c) ついで、工具基体の表面に、表2に示す化学蒸着条件で、目標平均層厚かつ目標組成の第2層(TiAlC層またはTiAlCN層)を形成した。表4、表5に示す本発明の被覆超硬工具1〜8(以下、本発明被覆工具1〜8という)を製造した。 (C) Next, a second layer (TiAlC layer or TiAlCN layer) having a target average layer thickness and a target composition was formed on the surface of the tool base under the chemical vapor deposition conditions shown in Table 2. The coated carbide tools 1 to 8 of the present invention shown in Tables 4 and 5 (hereinafter referred to as the present coated tools 1 to 8) were produced.

また、上記で作製した本発明被覆工具1〜8の内のいくつかについては、第2層の表面に、表2に示すAl層の化学蒸着条件で、表5に示す目標平均層厚のAl層を第3層として形成することにより、表4、表5に示す本発明の被覆超硬工具9〜12(以下、本発明被覆工具9〜12という)を製造した。 Also, for some of the present invention coated tool 1-8 prepared above, on the surface of the second layer, the chemical vapor deposition conditions of the Al 2 O 3 layer shown in Table 2, the target average layer shown in Table 5 By forming a thick Al 2 O 3 layer as the third layer, coated carbide tools 9 to 12 of the present invention shown in Tables 4 and 5 (hereinafter referred to as the present coated tools 9 to 12) were produced.

本発明被覆工具1〜12の硬質被覆層の縦断面について、電子線マイクロアナライザを用い、0.1μm×0.2μmの領域において面分析により、工具基体側界面の改質AlN層中であって、工具基体側界面から0.1μmまでの深さ領域におけるW、Co、Tiの含有量を測定し、それぞれの10点の測定値を平均することにより、工具基体側界面の改質AlN層中における平均W含有量、平均Co含有量および平均Ti含有量を求めた。
また、改質AlN層中におけるW、Co、Ti成分が、工具基体側から第2層側へ行くにしたがい、次第にその含有量が減少する組成傾斜構造を形成していることを確認するために、改質AlN層の層厚中間地点における平均W含有量、平均Co含有量および平均Ti含有量、さらに、改質AlN層の第2層との界面における平均W含有量、平均Co含有量および平均Ti含有量を、上記と同様にして求めた。
表4に、これらの値を示す。
なお、本発明における改質AlN層中のW含有量、Co含有量、Ti含有量とは、上記測定法によって求められた上記各成分の平均含有量のことを意味する。
About the longitudinal section of the hard coating layer of the present coated tool 1-12, using an electron beam microanalyzer, in the modified AlN layer on the tool substrate side interface by surface analysis in the region of 0.1 μm × 0.2 μm, In the modified AlN layer at the tool base side interface, the contents of W, Co, and Ti in the depth region from the tool base side interface to 0.1 μm are measured, and the measured values at the respective 10 points are averaged. The average W content, average Co content, and average Ti content were determined.
In order to confirm that the W, Co, Ti component in the modified AlN layer forms a composition gradient structure in which the content gradually decreases as it goes from the tool substrate side to the second layer side. The average W content, the average Co content and the average Ti content at the intermediate point of the layer thickness of the modified AlN layer, and the average W content, the average Co content at the interface between the modified AlN layer and the second layer, and The average Ti content was determined in the same manner as described above.
Table 4 shows these values.
In addition, the W content, the Co content, and the Ti content in the modified AlN layer in the present invention mean the average contents of the respective components obtained by the measurement method.






比較のため、前記(a)で作製した工具基体1〜4に対して、表2に示す化学蒸着条件で目標平均層厚のAlN層を形成し、ついで、表3に示す本発明外熱処理条件で熱処理を施し、AlN層の表面に、同じく表2に示す化学蒸着条件で、目標平均層厚かつ目標組成のTiAlC層またはTiAlCN層を形成することにより、表6、表7に示す比較例の被覆超硬工具1〜8(以下、比較例被覆工具1〜8という)を製造した。
また、比較例被覆工具1〜8の内のいくつかについては、第2層の表面に、表2に示すAl層の化学蒸着条件で、表7に示す目標平均層厚のAl層を第3層として形成することにより、表6、表7に示す比較例の被覆超硬工具9〜12(以下、比較例被覆工具9〜12という)を製造した。
For comparison, an AlN layer having a target average layer thickness is formed under the chemical vapor deposition conditions shown in Table 2 on the tool bases 1 to 4 produced in (a), and then the heat treatment conditions outside the present invention shown in Table 3 are applied. The TiAlC layer or the TiAlCN layer having the target average layer thickness and the target composition is formed on the surface of the AlN layer under the chemical vapor deposition conditions shown in Table 2 as well, in the comparative examples shown in Tables 6 and 7. Coated carbide tools 1 to 8 (hereinafter referred to as comparative example coated tools 1 to 8) were produced.
In Comparative Example for some of the coated tool 1-8, the surface of the second layer, the chemical vapor deposition conditions of the Al 2 O 3 layer shown in Table 2, the target average layer thickness of the Al 2 shown in Table 7 By forming the O 3 layer as the third layer, the coated carbide tools 9 to 12 of comparative examples shown in Tables 6 and 7 (hereinafter referred to as comparative coated tools 9 to 12) were manufactured.

比較例被覆工具1〜12の硬質被覆層の縦断面について、本発明被覆工具1〜12の場合と同様、電子線マイクロアナライザを用いて、工具基体側界面のAlN層中における平均W含有量、平均Co含有量および平均Ti含有量、AlN層の層厚中間地点における平均W含有量、平均Co含有量および平均Ti含有量、さらに、AlN層の第2層との界面における平均W含有量、平均Co含有量および平均Ti含有量を求めた。
表6に、これらの値を示す。
About the longitudinal section of the hard coating layer of Comparative Examples Coated Tools 1-12, the average W content in the AlN layer at the tool base side interface, as in the case of the coated tools 1-12 of the present invention, Average Co content and average Ti content, average W content at the middle point of the layer thickness of the AlN layer, average Co content and average Ti content, and average W content at the interface of the AlN layer with the second layer, Average Co content and average Ti content were determined.
Table 6 shows these values.



つぎに、上記の本発明被覆工具1〜12および比較例被覆工具1〜12について、次の切削条件で、切削加工試験を実施した。
切削条件A:
被削材: JIS・FC300の丸棒、
切削速度: 400m/min、
切り込み: 1.5mm、
送り量: 0.6mm/rev、
切削時間: 6分、
の条件での鋳鉄の高速高送り切削試験(通常の切削速度および送りは、それぞれ、300m/min、0.3mm/rev)。
切削条件B:
被削材: JIS・SCM440の丸棒、
切削速度: 350m/min、
切り込み: 1.5mm、
送り量: 0.6mm/rev、
切削時間: 10分、
の条件での合金鋼の高速高送り切削試験(通常の切削速度および送りは、それぞれ、250m/min、0.3mm/rev)。
そして、上記それぞれの切削試験における切刃の逃げ面摩耗幅を測定した。
表8に測定結果を示す。
Next, a cutting test was performed on the above-described coated tools 1 to 12 of the present invention and comparative coated tools 1 to 12 under the following cutting conditions.
Cutting condition A:
Work material: JIS / FC300 round bar,
Cutting speed: 400 m / min,
Cutting depth: 1.5mm,
Feed amount: 0.6mm / rev,
Cutting time: 6 minutes,
High-speed, high-feed cutting test of cast iron under the conditions (normal cutting speed and feed are 300 m / min and 0.3 mm / rev, respectively).
Cutting condition B:
Work material: JIS / SCM440 round bar,
Cutting speed: 350 m / min,
Cutting depth: 1.5mm,
Feed amount: 0.6mm / rev,
Cutting time: 10 minutes,
The high-speed high-feed cutting test of the alloy steel under the conditions (normal cutting speed and feed are 250 m / min and 0.3 mm / rev, respectively).
Then, the flank wear width of the cutting edge in each of the above cutting tests was measured.
Table 8 shows the measurement results.


表4〜8の結果から、本発明の被覆超硬工具においては、高熱発生を伴うとともに、切刃に高負荷が作用する鋼、鋳鉄等の高速高送り切削加工においても、工具基体と改質AlN層(第1層)との密着性が改善されることにより、チッピング、欠損、剥離等の異常損傷の発生が抑制され、長期の使用にわたってすぐれた耐摩耗性を発揮することが分かる。
これに対して、比較例の被覆超硬工具では、チッピング、欠損、剥離等の発生により、短時間で寿命に至ることは明らかである。
From the results shown in Tables 4 to 8, the coated carbide tool of the present invention is improved with the tool base even in high-speed and high-feed cutting such as steel and cast iron that cause high heat generation and high load on the cutting edge. It can be seen that by improving the adhesion with the AlN layer (first layer), the occurrence of abnormal damage such as chipping, chipping and peeling is suppressed, and excellent wear resistance is exhibited over a long period of use.
On the other hand, it is clear that the coated carbide tool of the comparative example reaches the end of its life in a short time due to the occurrence of chipping, chipping, peeling and the like.

本発明の表面被覆WC基超硬合金製切削工具は、鋼や鋳鉄の高速高送り切削加工ばかりでなく、切れ刃に高負荷が作用する高速断続、高速高切り込み切削加工等に供した場合でも、工具基体に対する硬質被覆層の密着性を確保することができ、長期間の使用にわたってすぐれた切削性能を示すことから、切削加工の省エネ化、低コスト化に十分満足に対応できるものである。













The surface-coated WC-based cemented carbide cutting tool of the present invention is not only used for high-speed and high-feed cutting of steel and cast iron, but also when subjected to high-speed interrupting, high-speed and high-cutting processing where a high load acts on the cutting edge Since the adhesion of the hard coating layer to the tool substrate can be ensured and the cutting performance is excellent over a long period of use, it is possible to satisfactorily cope with energy saving and cost reduction of the cutting process.













Claims (2)

硬質相成分としてWCを含有し、さらに、少なくともTi成分を含有するとともに、結合相成分としてCoを含有するWC基超硬合金を工具基体とし、該工具基体表面に、硬質被覆層を化学蒸着で被覆形成した表面被覆WC基超硬合金製切削工具において、
(a)上記硬質被覆層は、工具基体表面に被覆された第1層と、第1層の表面に被覆された第2層からなり、
(b)第1層は、0.5〜2μmの平均層厚を有するAlの窒化物を主体とする改質層、また、第2層は、2〜10μmの平均層厚を有するTiとAlの複合炭化物層またはTiとAlの複合炭窒化物層からなり、
(c)上記第1層中には、工具基体からの拡散によってW、CoおよびTiが含有され、第1層中における工具基体側界面のW含有量は2.2原子%以上7.8原子%以下、Co含有量は1.2原子%以上4.2原子%以下、Ti含有量は2.4原子%以上9.6原子%以下であり、
(d)上記第1層中におけるW含有量、Co含有量およびTi含有量は、いずれも、工具基体側から第2層側へ行くにしたがい、次第に減少している組成傾斜構造を示すことを特徴とする表面被覆WC基超硬合金製切削工具。
A WC-based cemented carbide containing WC as a hard phase component and further containing at least a Ti component and Co as a binder phase component is used as a tool base, and a hard coating layer is formed on the surface of the tool base by chemical vapor deposition. In the surface-coated WC-based cemented carbide cutting tool with the coating formed,
(A) The hard coating layer includes a first layer coated on the surface of the tool base and a second layer coated on the surface of the first layer,
(B) The first layer is a modified layer mainly composed of Al nitride having an average layer thickness of 0.5 to 2 μm, and the second layer is Ti and Al having an average layer thickness of 2 to 10 μm. A composite carbide layer of Ti or Al and a composite carbonitride layer of Ti and Al,
(C) The first layer contains W, Co, and Ti by diffusion from the tool base, and the W content at the tool base side interface in the first layer is 2.2 atomic% or more and 7.8 atoms. %, Co content is 1.2 atomic% or more and 4.2 atomic% or less, Ti content is 2.4 atomic% or more and 9.6 atomic% or less,
(D) The W content, the Co content, and the Ti content in the first layer all indicate a composition gradient structure that gradually decreases from the tool base side to the second layer side. A surface-coated WC-based cemented carbide cutting tool.
上記表面被覆WC基超硬合金製切削工具において、上記第2層の表面に、さらに、3〜10μmの平均層厚のAl層からなる第3層を化学蒸着により被覆形成したことを特徴とする請求項1に記載の表面被覆WC基超硬合金製切削工具。



























In the surface-coated WC-based cemented carbide cutting tool, a third layer made of Al 2 O 3 having an average layer thickness of 3 to 10 μm is further formed on the surface of the second layer by chemical vapor deposition. The surface-coated WC-based cemented carbide cutting tool according to claim 1,



























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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017167980A1 (en) * 2016-03-31 2017-10-05 Walter Ag Coated cutting tool with h-aln and ti1-xalxcynz layers

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017167980A1 (en) * 2016-03-31 2017-10-05 Walter Ag Coated cutting tool with h-aln and ti1-xalxcynz layers
CN108884562A (en) * 2016-03-31 2018-11-23 瓦尔特公开股份有限公司 With H-ALN layers and the cutting tool of TI1-XAlXCYNZ layers of coating
JP2019511378A (en) * 2016-03-31 2019-04-25 ヴァルター アーゲー Coated cutting tools with h-AlN and Ti1-xAlxCyNz layers
US11247276B2 (en) 2016-03-31 2022-02-15 Walter Ag Coated cutting tool with h-AlN and Ti1-xAlxCyNz layers

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