JP2010228088A - Surface-coated cutting tool - Google Patents
Surface-coated cutting tool Download PDFInfo
- Publication number
- JP2010228088A JP2010228088A JP2009081589A JP2009081589A JP2010228088A JP 2010228088 A JP2010228088 A JP 2010228088A JP 2009081589 A JP2009081589 A JP 2009081589A JP 2009081589 A JP2009081589 A JP 2009081589A JP 2010228088 A JP2010228088 A JP 2010228088A
- Authority
- JP
- Japan
- Prior art keywords
- cbn
- boron nitride
- phase
- film
- cutting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Cutting Tools, Boring Holders, And Turrets (AREA)
- Physical Vapour Deposition (AREA)
Abstract
Description
本発明は、切削加工時の耐チッピング性、耐摩耗性に優れるばかりか、被削材の仕上げ面精度にも優れ、特に、高硬度鋼等の切削工具として好適な、長期の使用にわたって優れた切削性能を発揮する表面被覆切削工具に関する。 The present invention is not only excellent in chipping resistance and wear resistance during cutting, but also excellent in the finished surface accuracy of the work material, and particularly excellent for long-term use, suitable as a cutting tool for high-hardness steel and the like. The present invention relates to a surface-coated cutting tool that exhibits cutting performance.
従来、高硬度鋼等の鉄系被削材の切削加工には、被削材との親和性の低い工具材料として、立方晶窒化ほう素（以下、ｃＢＮで示す）を用いることは良く知られており、例えば、ｃＢＮ焼結体それ自体を切削工具として使用したり（特許文献１、２）、ｃＢＮ焼結体からなる工具基体の表面にチタン系硬質膜を被覆することにより、切削工具の耐熱性、耐摩耗性、耐欠損性を高める（特許文献３）ことにより、切削工具としての特性向上が図られている。
しかし、ｃＢＮ焼結体は、通常、ｃＢＮ粉末を、金属、セラミック等の結合材と混合し、超高圧高温処理により焼結体として製造することが一般的であるが、この焼結体は、結合材を含むために、ｃＢＮに比して、硬度、熱伝導性等が劣り、ｃＢＮが本来備える特性を充分に生かしきれてはいない。
また、ｃＢＮ焼結体に硬質皮膜を被覆するにあたり、硬質膜と工具基体との付着強度が重要であり、そのため、例えば、ｃＢＮ工具基体の表面にＡｒボンバード処理などを施すことで、硬質膜と工具基体との付着強度を向上させることも知られている（特許文献４）。
しかし、近年の切削の高速化、高能率化をはじめとする切削条件の過酷化に伴い、上記のチタン系硬質膜を上記のｃＢＮ工具基体に被覆した工具では、耐熱性、耐摩耗性、耐欠損性が十分とはいえなくなってきているのが現状である。
そこで、チタン系硬質膜よりさらに硬質の膜を被覆した表面被覆切削工具の開発が期待されている。
Conventionally, it is well known to use cubic boron nitride (hereinafter referred to as cBN) as a tool material having low affinity with a work material for cutting of an iron-based work material such as high hardness steel. For example, the cBN sintered body itself can be used as a cutting tool (Patent Documents 1 and 2), or the surface of a tool base made of a cBN sintered body can be coated with a titanium-based hard film. By improving heat resistance, wear resistance, and fracture resistance (Patent Document 3), characteristics as a cutting tool are improved.
However, the cBN sintered body is generally produced by mixing cBN powder with a binder such as metal and ceramic and producing the sintered body by ultra-high pressure and high temperature treatment. Since the binder is included, the hardness, thermal conductivity, etc. are inferior to cBN, and the characteristics inherent to cBN are not fully utilized.
Further, in coating the hard film on the cBN sintered body, the adhesion strength between the hard film and the tool base is important. For example, the surface of the cBN tool base is subjected to Ar bombardment treatment, etc. It is also known to improve adhesion strength with a tool base (Patent Document 4).
However, with the recent severe cutting conditions such as high speed and high efficiency of cutting, a tool in which the above titanium-based hard film is coated on the above cBN tool base has heat resistance, wear resistance, The current situation is that the deficiency is not enough.
Therefore, development of a surface-coated cutting tool in which a hard film is further coated than a titanium-based hard film is expected.
ｃＢＮは、ダイヤモンドに次ぐ硬度を持ち、しかも熱的および化学的安定性にすぐれており、鉄系材料との反応性がダイヤモンドに比べて低いなどの特性を有することから、ｃＢＮが持っている特性を活かすべく、基材表面にｃＢＮからなる被覆層を形成することにより、低コストで基材の耐摩耗性、耐食性を向上させた成形体を得る試みが広く行われている。このようなｃＢＮによる被覆は、ＣＶＤ法やＰＶＤ法などにより、ｃＢＮの気相合成による被覆が可能になってきている。
しかしながら、上記の気相合成法によって得たｃＢＮ皮膜は、大きな内部応力をもっているため、成膜後に剥離を起こしやすい。
したがって、基材とｃＢＮ膜との付着強度を向上させることが大きな課題となっている。
cBN has the second highest hardness after diamond, and is excellent in thermal and chemical stability, and has characteristics such as low reactivity with iron-based materials compared to diamond. In order to make the best use of, the formation of a coating layer made of cBN on the surface of the base material has been widely attempted to obtain a molded body with improved wear resistance and corrosion resistance of the base material at low cost. Such cBN coating can be applied by vapor phase synthesis of cBN by CVD, PVD, or the like.
However, since the cBN film obtained by the above-mentioned vapor phase synthesis method has a large internal stress, it tends to peel off after film formation.
Therefore, improving the adhesion strength between the base material and the cBN film is a major issue.
本発明者等は、ｃＢＮ焼結体を工具基体材料とし、特に、高硬度鋼等の切削に際し最適な硬質被覆材料について鋭意研究したところ、次のような知見を得た。 The inventors of the present invention made a cBN sintered body as a tool base material, and, in particular, earnestly researched on an optimum hard coating material when cutting high-hardness steel or the like, and obtained the following knowledge.
ｃＢＮ焼結体からなる工具基体（以下、ｃＢＮ工具基体という）に含有されるｃＢＮの割合と、ｃＢＮを含有する窒化ほう素膜（以下、ｃＢＮ−ＢＮ膜で示す）の付着強度の関連性について数多くの実験を重ねたところ、比較的ｃＢＮの含有割合が高いｃＢＮ工具基体において、ｃＢＮ−ＢＮ膜の付着強度が優位であることを、まず見出した。 Regarding the relationship between the proportion of cBN contained in a tool substrate made of a cBN sintered body (hereinafter referred to as a cBN tool substrate) and the adhesion strength of a boron nitride film containing cBN (hereinafter referred to as a cBN-BN film) As a result of many experiments, it was first found that the adhesion strength of the cBN-BN film is superior in a cBN tool substrate having a relatively high content of cBN.
さらに、本発明者等は、ｃＢＮ−ＢＮ膜中のｃＢＮが、ｃＢＮ工具基体のｃＢＮ粒子の表面からエピタキシャル成長することを突き止め、ｃＢＮ粒子がｃＢＮ工具基体の表面に占める割合が多いほど、ｃＢＮ−ＢＮ膜の付着強度が向上することがわかった。即ち、膜中のｃＢＮは、工具基体の構成成分であるｃＢＮ粒子表面から柱状成長し、一方、ｃＢＮ粒子が工具基体表面に露出していない領域、例えば、結合相の上には、ｃＢＮの成長はほとんどなく、ｃＢＮ−ＢＮ膜中の、工具基体のｃＢＮ粒子表面から柱状成長して形成された柱状ｃＢＮ相の間には、六方晶窒化ほう素（以下、ｈＢＮで示す）相とアモルファスＢＮ（以下、ａ−ＢＮで示す）相を主体とする相が形成される（図１参照）。
そして、上記ｃＢＮ−ＢＮ膜中に形成されたｈＢＮ相およびａ−ＢＮ相は、潤滑性にすぐれるため、切削時の切粉と逃げ面表面との摩擦により生じるクレーター摩耗を抑制・低減することができる。
つまり、ｃＢＮ工具基体表面に、柱状ｃＢＮ相とその間を埋めるｈＢＮ相、ａ−ＢＮ相からなるｃＢＮ−ＢＮ膜を形成することによって、基体との付着強度に優れた柱状ｃＢＮ相で耐摩耗性が確保されるとともに、ｈＢＮ相、ａ−ＢＮ相の存在によって摩擦が低減され潤滑性が高められることから、耐摩耗性、高潤滑性を備えた表面被覆切削工具を提供することができる。
Furthermore, the present inventors have found that cBN in the cBN-BN film grows epitaxially from the surface of the cBN particle of the cBN tool base, and the greater the proportion of the cBN particles occupying the surface of the cBN tool base, the more cBN-BN It was found that the adhesion strength of the film was improved. That is, the cBN in the film grows in a columnar shape from the surface of the cBN particle that is a component of the tool base, while the cBN grows on a region where the cBN particle is not exposed on the tool base surface, for example, on the binder phase. In the cBN-BN film, a hexagonal boron nitride (hereinafter referred to as hBN) phase and amorphous BN (between the columnar cBN phases formed by columnar growth from the surface of the cBN particles of the tool substrate and amorphous BN ( Hereinafter, a phase mainly composed of a phase (shown as a-BN) is formed (see FIG. 1).
And since the hBN phase and the a-BN phase formed in the cBN-BN film have excellent lubricity, the crater wear caused by the friction between the chips and the flank surface during cutting is suppressed / reduced. Can do.
That is, by forming a cBN-BN film composed of a columnar cBN phase and an hBN phase and an a-BN phase between the columnar cBN phase on the surface of the cBN tool substrate, the columnar cBN phase having excellent adhesion strength to the substrate provides wear resistance. In addition to being ensured, the presence of the hBN phase and the a-BN phase reduces friction and improves lubricity, so that a surface-coated cutting tool having wear resistance and high lubricity can be provided.
更に、ｃＢＮ膜は、一般的に、成膜後に巨大な残留応力が存在することが大きな問題であったが、本発明のｃＢＮ−ＢＮ膜によれば、ｃＢＮ工具基体のｃＢＮ粒子表面からｃＢＮ相を柱状成長させるため、密着性に優れ剥離発生が防止されるばかりか、ｃＢＮ相が柱状に成長するため、ｃＢＮ−ＢＮ膜内に形成される残留応力（残留歪み）は少なく、さらに、柱状ｃＢＮ相間に存在するｈＢＮ相、ａ−ＢＮ相は、すぐれた潤滑性を有するとともに、切削時の熱衝撃、機械的衝撃を緩和し、ｃＢＮ−ＢＮ膜の剥離抑制に寄与する。 Furthermore, the cBN film generally has a big problem that a huge residual stress exists after the film formation. However, according to the cBN-BN film of the present invention, the cBN phase is separated from the cBN particle surface of the cBN tool base. The columnar growth allows excellent adhesion and prevents the occurrence of peeling, and the cBN phase grows in a columnar shape, so that the residual stress (residual strain) formed in the cBN-BN film is small, and the columnar cBN The hBN phase and the a-BN phase existing between the phases have excellent lubricity, and reduce thermal shock and mechanical shock during cutting, thereby contributing to suppression of peeling of the cBN-BN film.
以上のとおり、本発明では、ｃＢＮ工具基体表面に、柱状成長したｃＢＮ相を含むｃＢＮ−ＢＮ膜を被覆形成することによって、工具基体と被覆層の密着強度に優れ、高潤滑性とともにすぐれた耐摩耗性を備えた表面被覆切削工具を提供することができ、そして、このような表面被覆切削工具を高硬度鋼の乾式高切込み切削に用いた場合、長期の使用にわたって、すぐれた切削性能を発揮し、工具寿命も大幅に伸びることを本発明者等は知見したのである。 As described above, in the present invention, by forming a cBN-BN film containing a columnar-grown cBN phase on the surface of a cBN tool base, the adhesion strength between the tool base and the coating layer is excellent, and high lubricity and excellent resistance to resistance are obtained. Abrasive surface-coated cutting tools can be provided, and when such surface-coated cutting tools are used for dry high-cutting of high-hardness steel, they exhibit excellent cutting performance over a long period of use. The present inventors have found that the tool life is also greatly increased.
本発明は、上記知見に基づいてなされたものであって、
「 ４０〜７０体積％の立方晶窒化ほう素を含有し、残部は硬質分散相と結合相とからなる立方晶窒化ほう素基超高圧焼結材料製工具基体の表面に、０．５〜５．０μｍの平均膜厚の窒化ほう素膜を蒸着形成してなる表面被覆切削工具において、該窒化ほう素膜は、工具基体の構成成分である立方晶窒化ほう素の結晶から柱状成長した立方晶窒化ほう素からなる相と、アモルファス窒化ほう素、六方晶窒化ほう素および立方晶窒化ほう素からなる相で構成され、かつ、窒化ほう素膜に占める上記柱状成長した立方晶窒化ほう素からなる相の面積割合は、３０〜６０面積％であることを特徴とする表面被覆切削工具。」
を特徴とするものである。
The present invention has been made based on the above findings,
40 to 70% by volume of cubic boron nitride, and the balance is 0.5 to 5 on the surface of the tool base made of cubic boron nitride based ultrahigh pressure sintered material consisting of a hard dispersed phase and a binder phase. In a surface-coated cutting tool formed by vapor-depositing a boron nitride film having an average film thickness of 0.0 μm, the boron nitride film is a cubic crystal grown in a columnar shape from a cubic boron nitride crystal that is a component of the tool substrate. Consisting of a phase composed of boron nitride and a phase composed of amorphous boron nitride, hexagonal boron nitride and cubic boron nitride, and consisting of the above-grown cubic boron nitride occupying the boron nitride film A surface-coated cutting tool characterized in that the phase area ratio is 30 to 60 area%. "
It is characterized by.
本発明について、以下に説明する。 The present invention will be described below.
立方晶窒化ほう素基超高圧焼結材料製工具基体（ｃＢＮ工具基体）：
超高圧焼結材料製工具基体中の窒化ほう素（ｃＢＮ）は、きわめて硬質で、焼結材料中で分散相を形成し、そしてこの分散相によって耐摩耗性の向上を図ることができる。
本発明では、優れた耐摩耗性を備える表面被覆切削工具を提供することが大前提であるところ、ｃＢＮの含有割合が４０体積％未満であるような場合には、所望の耐摩耗性と付着強度を確保することができないので、ｃＢＮ含有割合は少なくとも４０体積％とする必要がある。一方、ｃＢＮ含有割合を多くしていくと、高硬度鋼の旋削加工において、逃げ面における耐摩耗性が低下し、本発明の被覆を行っても、所望の耐摩耗性を具備させることができなくなることから、ｃＢＮ含有割合の上限は７０体積％とする必要がある。
Cubic boron nitride based ultra-high pressure sintered material tool substrate (cBN tool substrate):
Boron nitride (cBN) in a tool base made of an ultra-high pressure sintered material is extremely hard and forms a dispersed phase in the sintered material, and this dispersed phase can improve wear resistance.
In the present invention, it is a major premise to provide a surface-coated cutting tool having excellent wear resistance. When the content of cBN is less than 40% by volume, desired wear resistance and adhesion can be obtained. Since the strength cannot be ensured, the cBN content ratio needs to be at least 40% by volume. On the other hand, when the cBN content is increased, the wear resistance on the flank face is reduced in turning of high hardness steel, and even if the coating of the present invention is performed, the desired wear resistance can be achieved. Therefore, the upper limit of the cBN content ratio needs to be 70% by volume.
例えば、ｃＢＮ工具基体の結合相等として、周期律表ＶＩａ、Ｖａ、ＶＩａ族元素の窒化物、炭化物、硼化物、酸化物ならびにこれらの固溶体からなる群の中から選択された少なくとも１種とアルミニウム化合物のセラミックス系結合材を用いるような場合には、４０〜７０体積％のｃＢＮを使用することが可能である。 For example, at least one selected from the group consisting of nitrides, carbides, borides, oxides, and solid solutions of the periodic table VIa, Va, and VIa group elements as the binder phase of the cBN tool base and an aluminum compound In the case of using such a ceramic-based binder, it is possible to use 40 to 70% by volume of cBN.
硬質膜（ｃＢＮ−ＢＮ膜）：
本発明では、マグネトロンスパッタリングによって、ｃＢＮ工具基体表面にｃＢＮ−ＢＮ膜からなる硬質膜を成膜することができる。
例えば、図２に示すように、ｈＢＮターゲット（図２中ではｈ−ＢＮで示されている）を配置したマグネトロンスパッタ装置と、高周波バイアス装置からなる反応容器を、基体温度を４５０℃に保持しながら、反応容器内にＡｒとＮ２混合ガスを流量比で１：１の割合で導入し、全圧を３．３Ｐａになるように制御し、ターゲット側に５００Ｗ、基体側に６０Ｗの電力量で、１３．５６ＭＨｚの周波数の高周波を印加し、さらに、マグネトロンスパッタ装置に１３．５６ＭＨｚの周波数の高周波を印加し、基体バイアスを−２５０Ｖにしてスパッタリングすることにより、柱状に成長したｃＢＮが含まれるｃＢＮ−ＢＮ膜を形成することができる。
また、雰囲気ガスを、ＡｒとＮ２混合ガスから１００％Ａｒガスに替えることにより、基体バイアスが−１５０Ｖという比較的低い基体バイアス電圧でも、ｃＢＮ相が形成される。この場合、低バイアスでｃＢＮ相を形成できることから、比較的内部応力の低い柱状に成長したｃＢＮが含まれるｃＢＮ―ＢＮ膜を成膜することができる。
Hard film (cBN-BN film):
In the present invention, a hard film made of a cBN-BN film can be formed on the surface of the cBN tool base by magnetron sputtering.
For example, as shown in FIG. 2, a reaction vessel comprising a magnetron sputtering apparatus having a hBN target (indicated by h-BN in FIG. 2) and a high-frequency bias apparatus is maintained at a substrate temperature of 450.degree. However, Ar and N 2 mixed gas was introduced into the reaction vessel at a flow rate ratio of 1: 1, and the total pressure was controlled to be 3.3 Pa, and the power amount was 500 W on the target side and 60 W on the substrate side. Then, a high frequency having a frequency of 13.56 MHz is applied, and a high frequency having a frequency of 13.56 MHz is applied to the magnetron sputtering apparatus, and sputtering is performed with the substrate bias set to −250 V, so that cBN grown in a columnar shape is included. A cBN-BN film can be formed.
Further, by changing the atmosphere gas from Ar and N 2 mixed gas to 100% Ar gas, a cBN phase is formed even with a relatively low substrate bias voltage of −150 V. In this case, since the cBN phase can be formed with a low bias, a cBN-BN film containing cBN grown in a column shape with relatively low internal stress can be formed.
上記のとおり、本発明では、４０〜７０体積％のｃＢＮを含有するｃＢＮ工具基体表面に、密着強度が高いｃＢＮ−ＢＮ硬質膜が形成されるため、硬質膜の剥離発生はなく、さらに、柱状成長したｃＢＮ相の間に存在するｈＢＮ相、ａ−ＢＮ相によって、切削加工時の硬質膜の潤滑性が担保されるので、本発明の表面被覆切削工具を、厳しい切削条件である高硬度鋼の乾式高切込み切削加工に用いた場合も、チッピング、欠損の発生の恐れはなく、しかも、すぐれた耐摩耗性を維持したまま、長期の使用にわたって、すぐれた切削性能を発揮し、工具寿命の大幅な延長を図ることが可能である。 As described above, in the present invention, the cBN-BN hard film having high adhesion strength is formed on the surface of the cBN tool base containing 40 to 70% by volume of cBN. The hBN phase and the a-BN phase existing between the grown cBN phases ensure the lubricity of the hard film during the cutting process, so that the surface-coated cutting tool of the present invention is made of a high-hardness steel having severe cutting conditions. Even when used in dry high-cutting machining, there is no risk of chipping or chipping, and excellent cutting performance is demonstrated over a long period of use while maintaining excellent wear resistance. A significant extension is possible.
以下に、本発明の表面被覆切削工具を実施例に基づいて説明する。 Below, the surface covering cutting tool of this invention is demonstrated based on an Example.
原料粉末として、いずれも０．５〜４μｍの範囲内の平均粒径を有する立方晶窒化硼素（ｃＢＮ）粉末、窒化チタン（ＴｉＮ）粉末、Ａｌ粉末、酸化アルミニウム（Ａｌ２Ｏ３）粉末、炭化タングステン（ＷＣ）粉末を用意し、これら原料粉末を表１に示される配合組成に配合し、ボールミルで８０時間湿式混合し、乾燥した後、１２０ＭＰａの圧力で直径：５０ｍｍ×厚さ：１．５ｍｍの寸法をもった圧粉体にプレス成形し、ついでこの圧粉体を、圧力：１Ｐａの真空雰囲気中、９００〜１３００℃の範囲内の所定温度に６０分間保持の条件で焼結して切刃片用予備焼結体とし、この予備焼結体を、別途用意した、Ｃｏ：８質量％、ＷＣ：残りの組成、並びに直径：５０ｍｍ×厚さ：２ｍｍの寸法をもったＷＣ基超硬合金製支持片と重ね合わせた状態で、通常の超高圧焼結装置に装入し、通常の条件である圧力：５ＧＰａ、温度：１２００〜１４００℃の範囲内の所定温度に保持時間：０．８時間の条件で超高圧焼結し、焼結後上下面をダイヤモンド砥石を用いて研磨し、ワイヤー放電加工装置にて一辺３ｍｍの正三角形状に分割し、さらにＣｏ：５質量％、ＴａＣ：５質量％、ＷＣ：残りの組成およびＣＩＳ規格ＣＮＧＡ１２０４１２の形状（厚さ：４．７６mm×一辺長さ：１２．７mmの正三角形）をもったＷＣ基超硬合金製チップ本体のろう付け部（コーナー部）に、質量％で、Ｃｕ：２６％、Ｔｉ：５％、Ｎｉ：２．５％、Ａｇ：残りからなる組成を有するＡｇ合金のろう材を用いてろう付けし、所定寸法に外周加工した後、切刃部に幅：０．１３ｍｍ、角度：２５°のホーニング加工を施し、さらに仕上げ研摩を施すことによりＩＳＯ規格ＣＮＧＡ１２０４１２のチップ形状をもったｃＢＮ含有割合が４０〜７０体積％であるｃＢＮ工具基体１〜１０を製造した。
また、ｃＢＮ工具基体１〜１０のｃＢＮ含有割合をｃＢＮ焼結体中のｃＢＮの配合組成に基づき体積％で算出し、ｃＢＮ工具基体１〜１０のそれぞれの表面に露出しているｃＢＮ粒子の面積割合を、ＳＥＭ（走査型電子顕微鏡）により観察された反射電子像のｃＢＮ粒子の表面に占める割合として算出し、それらの値を表３に示した。
As raw material powders, cubic boron nitride (cBN) powder, titanium nitride (TiN) powder, Al powder, aluminum oxide (Al 2 O 3 ) powder, carbonized, all having an average particle size in the range of 0.5 to 4 μm. Tungsten (WC) powder is prepared, these raw material powders are blended in the blending composition shown in Table 1, wet-mixed for 80 hours by a ball mill, dried, and then diameter: 50 mm × thickness: 1.5 mm at a pressure of 120 MPa. The green compact is then press-molded into a green compact, and the green compact is sintered and cut in a vacuum atmosphere at a pressure of 1 Pa at a predetermined temperature in the range of 900 to 1300 ° C. for 60 minutes. A pre-sintered body for blade pieces, and this pre-sintered body was prepared separately, WC-based cemented carbide with Co: 8% by mass, WC: remaining composition, and diameter: 50 mm × thickness: 2 mm Superposed with alloy support piece In a normal ultrahigh pressure sintering apparatus, and under normal conditions of pressure: 5 GPa, temperature: predetermined temperature within a range of 1200-1400 ° C., holding time: over 0.8 hours After sintering, the upper and lower surfaces are polished with a diamond grindstone and divided into 3 mm regular triangles with a wire electric discharge machine, and Co: 5 mass%, TaC: 5 mass%, WC: The remaining composition and the mass of the brazing part (corner part) of the WC-based cemented carbide chip body having the shape of CIS standard CNGA120412 (thickness: 4.76 mm × one side length: 12.7 mm) %: Cu: 26%, Ti: 5%, Ni: 2.5%, Ag: Brazing using a brazing material of an Ag alloy having the composition consisting of the remainder, and after outer peripheral processing to a predetermined dimension, the cutting blade Width: 0.13mm, angle: 25 ° Subjected to ring machining further cBN content having a tip shape of ISO standard CNGA120412 by performing finish polishing is to produce a cBN tool substrate 10 is 40 to 70 vol%.
Moreover, the cBN content ratio of the cBN tool bases 1 to 10 is calculated by volume% based on the composition of cBN in the cBN sintered body, and the area of the cBN particles exposed on the respective surfaces of the cBN tool bases 1 to 10 The ratio was calculated as the ratio of the backscattered electron image observed by the SEM (scanning electron microscope) to the surface of the cBN particles, and these values are shown in Table 3.
ついで、上記のｃＢＮ工具基体１〜１０を、アセトン中で洗浄し、乾燥した状態で、図２に示されるマグネトロンスパッタリング装置内に装着した。
４３０℃まで加熱した後、Ａｒガスを導入し、１．５ＰａのＡｒガス雰囲気とし、ｃＢＮ工具基体１に−１０５０Ｖの直流バイアス電圧を印加して、前記ｃＢＮ工具基体１〜１０をＡｒボンバード洗浄した。
（なお、Ａｒボンバード処理は、必ず行う必要のある処理であるというわけではないが、ｃＢＮ工具基体とｃＢＮ−ＢＮ膜とのより一段の密着性向上を図る上では、非常に有効な処理である。）
その後、表２に示される条件で、ＡｒとＮ２の混合ガスあるいはＡｒガスを導入し、作動圧を２〜７Ｐａになるように制御し、ターゲット側に５００Ｗ、基体側に６０Ｗ１３．５６ＭＨｚの周波数の高周波を印加し、さらにマグネトロンスパッタ装置に１３．５６ＭＮｚの周波数の高周波を印加し、基体バイアスを−１５０〜−２８０Ｖにして０．５〜２時間成膜することにより、平均膜厚０．５〜５μｍのｃＢＮ−ＢＮ膜からなる硬質膜を蒸着形成した本発明表面被覆切削工具１〜１０を得た。
Next, the cBN tool bases 1 to 10 were washed in acetone and dried, and mounted in the magnetron sputtering apparatus shown in FIG.
After heating to 430 ° C., Ar gas was introduced to form an Ar gas atmosphere of 1.5 Pa, a DC bias voltage of −1050 V was applied to the cBN tool base 1, and the cBN tool bases 1 to 10 were cleaned by Ar bombardment. .
(Note that the Ar bombardment process is not necessarily performed, but is an extremely effective process for further improving the adhesion between the cBN tool base and the cBN-BN film. .)
Thereafter, a mixed gas of Ar and N 2 or Ar gas is introduced under the conditions shown in Table 2, and the operating pressure is controlled to be 2 to 7 Pa. The frequency is 500 W on the target side and 60 W 13.56 MHz on the base side. Then, a high frequency of 13.56 MNz is applied to the magnetron sputtering apparatus, and the substrate bias is set to −150 to −280 V for 0.5 to 2 hours to form an average film thickness of 0.5. The surface-coated cutting tools 1 to 10 of the present invention in which a hard film composed of a cBN-BN film of ˜5 μm was formed by vapor deposition were obtained.
本発明表面被覆切削工具１〜１０の硬質膜（ｃＢＮ−ＢＮ膜）について、原子間力顕微鏡により組織観察したところ、いずれの硬質膜にも、柱状成長したｃＢＮ相によって形成される三角錐状の部分と、主として、ｈＢＮ相またはａ−ＢＮ相によって形成される平坦部とが観察された。
なお、硬質膜の組織に影響を与える要因は、特に、工具基体表面に露出して存在するｃＢＮ粒子の平均粒径と、ｃＢＮ粒子の面積割合である。
About the hard film (cBN-BN film) of the surface-coated cutting tools 1 to 10 of the present invention, the structure of the hard film was observed with an atomic force microscope. A portion and a flat portion mainly formed by the hBN phase or the a-BN phase were observed.
The factors that affect the structure of the hard film are, in particular, the average particle size of the cBN particles that are exposed on the surface of the tool base and the area ratio of the cBN particles.
さらに、本発明表面被覆切削工具１〜１０のｃＢＮ−ＢＮ膜中で柱状ｃＢＮ相の占める面積割合、およびｃＢＮ−ＢＮ膜の平均膜厚を測定した。
それぞれの測定法は、以下のとおりである。
ｃＢＮ−ＢＮ膜の被覆された表面被覆切削工具を切断し、断面のｃＢＮ−ＢＮ膜を透過型電子顕微鏡（ＴＥＭ）により観察し、柱状のｃＢＮを確認し、ｃＢＮ−ＢＮ膜に占めるｃＢＮの割合を算出し、それをｃＢＮの面積割合とした。
さらに、走査型電子顕微鏡（ＳＥＭ）により、断面のｃＢＮ−ＢＮ膜の膜厚を測定した。
これらの値を、表３に示す。
Further, the area ratio of the columnar cBN phase in the cBN-BN film of the surface-coated cutting tools 1 to 10 of the present invention and the average film thickness of the cBN-BN film were measured.
Each measuring method is as follows.
A surface-coated cutting tool coated with a cBN-BN film is cut, the cross-section cBN-BN film is observed with a transmission electron microscope (TEM), columnar cBN is confirmed, and the proportion of cBN in the cBN-BN film Was calculated as the area ratio of cBN.
Furthermore, the thickness of the cBN-BN film in the cross section was measured with a scanning electron microscope (SEM).
These values are shown in Table 3.
比較のため、実施例で使用したｃＢＮ工具基体１〜１０の上に、表４に示されるＴｉとＡｌの複合窒化物等からなる硬質被覆層を、アークイオンプレーティング法により０．６〜４．５μｍの平均層厚に蒸着形成することにより、比較例表面被覆切削工具１〜１０を作製した。 For comparison, on the cBN tool bases 1 to 10 used in the examples, a hard coating layer made of a composite nitride of Ti and Al shown in Table 4 is 0.6 to 4 by an arc ion plating method. Comparative example surface-coated cutting tools 1 to 10 were produced by vapor deposition to an average layer thickness of 0.5 μm.
上記の本発明表面被覆切削工具１〜１０と比較例表面被覆切削工具１〜１０を用い、以下の切削加工条件で切削加工試験を実施した。
《切削条件１》
被削材：ＪＩＳ・ＳＵＪ２の丸棒（硬さ：ＨＲＡ６０）、
切削速度：２５０ｍ／ｍｉｎ、
送り：０．１５ｍｍ／ｒｅｖ、
切込み：０．３０ｍｍ（高切込み条件に相当）、
切削時間：１０分
の条件での、焼入れ軸受鋼の乾式高速高切込み切削加工試験、
《切削条件２》
被削材：ＪＩＳ・ＳＣｒ４２０の丸棒（硬さ：ＨＲＡ６２）、
切削速度：２５０ｍ／ｍｉｎ、
送り：０．１０ｍｍ／ｒｅｖ、
切込み：０．３５ｍｍ（高切込み条件に相当）、
切削時間：１０分
の条件で、高硬度クロム鋼の高速高切込み切削加工試験、
を行い、切刃の逃げ面摩耗幅を測定した。
上記切削条件１，２による切削加工試験の測定結果を表５に示した。
Using the surface-coated cutting tools 1 to 10 of the present invention and the surface-coated cutting tools 1 to 10 of the comparative example, a cutting test was performed under the following cutting conditions.
<< Cutting conditions 1 >>
Work material: JIS / SUJ2 round bar (Hardness: H R A60),
Cutting speed: 250 m / min,
Feed: 0.15mm / rev,
Cutting depth: 0.30mm (equivalent to high cutting depth),
Cutting time: Dry high-speed high-cut cutting test of hardened bearing steel under conditions of 10 minutes,
<< Cutting conditions 2 >>
Work material: JIS / SCr420 round bar (Hardness: H R A62),
Cutting speed: 250 m / min,
Feed: 0.10mm / rev,
Cutting depth: 0.35 mm (corresponding to high cutting conditions),
Cutting time: High-speed, high-cut cutting test of high-hardness chromium steel under the condition of 10 minutes,
The flank wear width of the cutting blade was measured.
The measurement results of the cutting test under the cutting conditions 1 and 2 are shown in Table 5.
表３〜５に示される結果から、本発明表面被覆切削工具１〜１０は、４０〜７０体積％のｃＢＮを含有するｃＢＮ工具基体表面に、窒化ほう素からなる硬質膜（ｃＢＮ―ＢＮ膜）が形成され、かつ、該膜中には、３０〜６０面積％の柱状成長したｃＢＮ相が含まれ、さらに、該柱状成長したｃＢＮ相の間にｈＢＮ相、ａ−ＢＮ相、ｃＢＮ相が存在するため、ｃＢＮ工具基体と硬質膜との付着強度が向上し、すぐれた潤滑性、耐熱衝撃性、耐機械的衝撃性および耐摩耗性を兼ね備え、高硬度鋼の高切込み等の重切削条件に用いた場合でも、長期の使用にわたって、すぐれた切削性能を発揮し、工具寿命の大幅な延長が図られるのに対して、比較例表面被覆切削工具１〜１０においては、ｃＢＮ工具基体自体の破損、硬質膜の剥離・欠損等により工具寿命は短く、しかも、耐摩耗性にも劣るものであった。 From the results shown in Tables 3 to 5, the surface-coated cutting tools 1 to 10 of the present invention have a hard film (cBN-BN film) made of boron nitride on the surface of a cBN tool base containing 40 to 70% by volume of cBN. And 30-60% by area of column-grown cBN phase is included in the film, and hBN phase, a-BN phase, and cBN phase exist between the column-grown cBN phases. Therefore, the adhesion strength between the cBN tool base and the hard film is improved, and it has excellent lubricity, thermal shock resistance, mechanical shock resistance and wear resistance, and is suitable for heavy cutting conditions such as high cutting of high hardness steel. Even when used, the cutting performance is excellent over a long period of use and the tool life is greatly extended. On the other hand, in the comparative surface-coated cutting tools 1 to 10, the cBN tool base itself is damaged. , Due to peeling or chipping of hard film Ingredients life is short, moreover, it was inferior in wear resistance.
上述のように、この発明の表面被覆切削工具は、硬質膜に対して大きな熱的・機械的負荷が作用する高硬度鋼の重切削加工用の切削工具として好適であり、切削加工装置の高性能化、並びに切削加工の省力化および省エネ化、さらに低コスト化に十分満足に対応できるものであるが、各種の鋼や鋳鉄などの通常の切削条件での切削加工に使用可能であること勿論である。 As described above, the surface-coated cutting tool of the present invention is suitable as a cutting tool for heavy cutting of high-hardness steel in which a large thermal / mechanical load acts on a hard film. It can be used satisfactorily for performance, labor saving and energy saving of cutting, and cost reduction, but it can be used for cutting under normal cutting conditions such as various steels and cast irons. It is.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009081589A JP5407487B2 (en) | 2009-03-30 | 2009-03-30 | Surface coated cutting tool |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009081589A JP5407487B2 (en) | 2009-03-30 | 2009-03-30 | Surface coated cutting tool |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2010228088A true JP2010228088A (en) | 2010-10-14 |
| JP5407487B2 JP5407487B2 (en) | 2014-02-05 |
Family
ID=43044445
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2009081589A Expired - Fee Related JP5407487B2 (en) | 2009-03-30 | 2009-03-30 | Surface coated cutting tool |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5407487B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012032966A1 (en) * | 2010-09-07 | 2012-03-15 | 住友電工ハードメタル株式会社 | Cutting tool |
| JP2015110258A (en) * | 2013-10-31 | 2015-06-18 | 三菱マテリアル株式会社 | Surface coating cutting tool having excellent anti-chipping property |
| CN106119798A (en) * | 2016-08-19 | 2016-11-16 | 南京航空航天大学 | The preparation method of anode film linear ion source auxiliary cubic boron nitride coated cutting tool |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60204686A (en) * | 1984-03-27 | 1985-10-16 | 三菱マテリアル株式会社 | Surface-coated cubic boron nitride base ceramic member for cutting tool |
| JPS6141768A (en) * | 1984-07-31 | 1986-02-28 | Sumitomo Electric Ind Ltd | Composite hard film coated tool |
| JPH04280973A (en) * | 1991-03-07 | 1992-10-06 | Sumitomo Electric Ind Ltd | Boron nitride coated hard material |
| JPH0811004A (en) * | 1994-06-30 | 1996-01-16 | Nachi Fujikoshi Corp | High hardness composite covered tool |
| JP2002263913A (en) * | 2001-03-13 | 2002-09-17 | Toshiba Tungaloy Co Ltd | Covering hard member |
-
2009
- 2009-03-30 JP JP2009081589A patent/JP5407487B2/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60204686A (en) * | 1984-03-27 | 1985-10-16 | 三菱マテリアル株式会社 | Surface-coated cubic boron nitride base ceramic member for cutting tool |
| JPS6141768A (en) * | 1984-07-31 | 1986-02-28 | Sumitomo Electric Ind Ltd | Composite hard film coated tool |
| JPH04280973A (en) * | 1991-03-07 | 1992-10-06 | Sumitomo Electric Ind Ltd | Boron nitride coated hard material |
| JPH0811004A (en) * | 1994-06-30 | 1996-01-16 | Nachi Fujikoshi Corp | High hardness composite covered tool |
| JP2002263913A (en) * | 2001-03-13 | 2002-09-17 | Toshiba Tungaloy Co Ltd | Covering hard member |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012032966A1 (en) * | 2010-09-07 | 2012-03-15 | 住友電工ハードメタル株式会社 | Cutting tool |
| JPWO2012032966A1 (en) * | 2010-09-07 | 2014-01-20 | 住友電工ハードメタル株式会社 | Cutting tools |
| JP2015127095A (en) * | 2010-09-07 | 2015-07-09 | 住友電工ハードメタル株式会社 | Cutting tool |
| JP5765658B2 (en) * | 2010-09-07 | 2015-08-19 | 住友電工ハードメタル株式会社 | Cutting tools |
| US9186728B2 (en) | 2010-09-07 | 2015-11-17 | Sumitomo Electric Hardmetal Corp. | Cutting tool |
| JP2015110258A (en) * | 2013-10-31 | 2015-06-18 | 三菱マテリアル株式会社 | Surface coating cutting tool having excellent anti-chipping property |
| CN106119798A (en) * | 2016-08-19 | 2016-11-16 | 南京航空航天大学 | The preparation method of anode film linear ion source auxiliary cubic boron nitride coated cutting tool |
Also Published As
| Publication number | Publication date |
|---|---|
| JP5407487B2 (en) | 2014-02-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5614460B2 (en) | cBN sintered body tool and coated cBN sintered body tool | |
| JP5305056B1 (en) | Cutting tool made of cubic boron nitride based sintered body | |
| JP2016107396A (en) | Surface-coated cutting tool with excellent chipping resistance and wear resistance | |
| JP6439975B2 (en) | Cermet manufacturing method | |
| WO2015147249A1 (en) | Cubic boron nitride sintered body cutting tool | |
| JP5402515B2 (en) | Surface coated cutting tool | |
| JP2014121748A (en) | Surface-coated cutting tool made of cubic crystal boron nitride group superhigh pressure sintered material excellent in crack resistance | |
| JP5402507B2 (en) | Surface coated cutting tool | |
| JP2011212832A (en) | Cutting tool made of cubic boron nitride group ultrahigh pressure sintered material | |
| JP5594568B2 (en) | Cutting tool made of cubic boron nitride based ultra high pressure sintered material and cutting tool made of surface coated cubic boron nitride based ultra high pressure sintered material | |
| JP2007084382A (en) | Cubic boron nitride sintered compact, coated cubic boron nitride sintered compact, and cutting tool for quench-hardened steel comprising the same | |
| WO2016084939A1 (en) | Surface-coated cutting tool with excellent chipping resistance and wear resistance | |
| JP6213269B2 (en) | Surface-coated cutting tool that exhibits excellent chipping resistance over a long period of time when cutting hardened steel | |
| JP2008254159A (en) | Surface-coated cutting tool made of cubic boron nitride group ultrahigh-pressure sintered material | |
| JP5407487B2 (en) | Surface coated cutting tool | |
| JP2015030061A (en) | Surface-coated cutting tool superior in chipping resistance | |
| JP2010284759A (en) | Surface coated cutting tool | |
| JP2011051060A (en) | Surface coating cutting tool | |
| JP5321360B2 (en) | Surface coated cutting tool | |
| JP5686247B2 (en) | Cutting tool made of surface coated cubic boron nitride based ultra high pressure sintered material | |
| JP4770284B2 (en) | Cutting tips made of surface-coated cubic boron nitride-based ultra-high pressure sintered material with excellent wear resistance in high-speed intermittent cutting of high-hardness steel | |
| JP5246596B2 (en) | Cutting tool made of surface coated cubic boron nitride based ultra high pressure sintered material | |
| JP5239061B2 (en) | Coated cBN sintered body tool that suppresses damage at the lateral boundary of the cutting edge | |
| JP5234515B2 (en) | A surface-coated cutting tool with a hard coating layer that provides excellent fracture resistance and wear resistance | |
| JP6172519B2 (en) | Surface-coated cutting tool that exhibits excellent chipping resistance over a long period of time when cutting hardened steel |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20110928 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20130131 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20130507 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20130613 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20131008 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20131021 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 5407487 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| LAPS | Cancellation because of no payment of annual fees |