JPH0513762B2 - - Google Patents
Info
- Publication number
- JPH0513762B2 JPH0513762B2 JP63226075A JP22607588A JPH0513762B2 JP H0513762 B2 JPH0513762 B2 JP H0513762B2 JP 63226075 A JP63226075 A JP 63226075A JP 22607588 A JP22607588 A JP 22607588A JP H0513762 B2 JPH0513762 B2 JP H0513762B2
- Authority
- JP
- Japan
- Prior art keywords
- phase
- cutting
- ticn
- cutting tool
- hard phase
- 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.)
- Expired - Lifetime
Links
- 239000011195 cermet Substances 0.000 claims description 19
- 239000002344 surface layer Substances 0.000 claims description 11
- 239000010410 layer Substances 0.000 claims description 8
- 239000011230 binding agent Substances 0.000 claims description 7
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 5
- 239000010936 titanium Substances 0.000 claims description 5
- 229910052719 titanium Inorganic materials 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 150000002739 metals Chemical class 0.000 claims description 4
- 150000004767 nitrides Chemical class 0.000 claims description 4
- 239000012535 impurity Substances 0.000 claims description 3
- 230000000737 periodic effect Effects 0.000 claims description 3
- 150000001247 metal acetylides Chemical class 0.000 claims description 2
- 230000008520 organization Effects 0.000 claims 1
- 239000012071 phase Substances 0.000 description 29
- 238000005245 sintering Methods 0.000 description 16
- 238000000034 method Methods 0.000 description 12
- 239000012298 atmosphere Substances 0.000 description 7
- 239000000203 mixture Substances 0.000 description 7
- 239000000843 powder Substances 0.000 description 7
- 239000012299 nitrogen atmosphere Substances 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 239000002994 raw material Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Landscapes
- Cutting Tools, Boring Holders, And Turrets (AREA)
Description
〔産業上の利用分野〕
この発明は、特に高速切削や、高送りおよび高
切込み切削などの重切削に用いた場合にすぐれた
切削性能を長期に亘つて発揮する炭窒化チタン
（以下TiCNで示す）基サーメツト製切削工具に
関するものである。
〔従来の技術〕
従来、一般に、鋼などの切削に、
結合相形成成分としてCoおよびNiのうちの１
種または２種：５〜30％、
硬質相形成成分として周期律表の4a、5a、お
よび6a族金属の炭化物、窒化物、および炭窒化
物、並びにこれらの２種以上の固溶体（ただし、
TiCN、並びに6a族金属の窒化物および炭窒化物
を除くとともに、これら全体を(M)Ｃ・Ｎで示し、
Ｍは周期律表の4a、5aおよび6a族金属の１種以
上を示す）のうちの１種または２種以上：0.1〜
35％、
を含有し、残りが同じく硬質相形成成分としての
TiCNと不可避不純物からなる組成（以上重量
％、以下％は重量％を示す）を有するTiCN基サ
ーメツト製切削工具が用いられている。この
TiCN基サーメツト製切削工具の組織は、硬質相
と結合相からなり、上記硬質相は有芯部と外周部
で成分組成の異なる２重相構造（有芯構造）組
織、または上記２重相構造と全体が均一な成分組
成を有する単相構造の混合組織を有することが知
られている。
〔発明が解決しようとする課題〕
一方、近年の切削加工能率の高能率化に伴い、
高速切削や高送り切削が適用される傾向にある
が、上記の従来TiCN基サーメツト製切削工具に
おいては、高速切削や高送り切削に用いた場合に
は、比較的短時間で使用寿命に至るのが現状であ
る。
〔課題を解決するための手段〕
そこで、本発明者等は、上述のような観点か
ら、上記の従来TiCN基サーメツト製切削工具よ
りも一層長期に亘つて優れた切削性能を発揮する
TiCN基サーメツト製切削工具を得るべく研究を
行なつた結果、
従来TiCN基サーメツト製切削工具の製造にお
いて、その焼結に際しては、主成分であるTiCN
や他の合金成分である窒化物および炭窒化物が分
解して脱窒しないようにするために、少なくとも
脱窒開始温度から焼結温度までの昇温過程、焼結
温度保持過程、および冷却過程を窒素雰囲気とし
ていたが、これを、常温から脱窒開始温度越え〜
液相出現温度末端の範囲内の所定温度までの昇温
過程を、真空などの脱窒雰囲気またはCO2ガス含
有の脱炭雰囲気とし、続いての残りの焼結温度ま
での昇温過程、焼結温度保持過程、および冷却過
程を同じく窒素雰囲気とすると、焼結後のTiCN
基サーメツトの表面部には、単相構造の硬質相と
結合相からなる組織の表面層が形成されるように
なり、この表面層を有する炭窒化チタン基サーメ
ツト製切削工具を高速切削や高送り切削に用いた
場合にすぐれた切削性能を長期に亘つて発揮する
ようになるという知見を得たのである。
この発明は、上記知見にもとづいてなされたも
のであつて、
結合相形成成分としてCoおよびNiのうちの１
種または２種：５〜30％、
硬質相形成成分としての(M)Ｃ・Ｎのうちの１種
または２種：0.1〜35％、
を含有し、残りが同じく硬質相形成成分としての
TiCNと不可避不純物からなる組成を有し、かつ
硬質相が、２重相構造（有芯構造）組織、または
２重相構造と単相構造の混合組織を有するTiCN
基サーメツト製切削工具の表面部に、単相構造の
硬質相と結合相からなる表面層を１〜10μｍの平
均層厚で形成してなるTiCN基サーメツト製切削
工具に特徴を有するものである。
つぎに、この発明の切削工具において、TiCN
基サーメツトの成分組成および表面層の平均層厚
を上記の通りに限定した理由を説明する。
(a) CoおよびNiの含有量
これらの成分には、分散する硬質相と強固に
結合し、かつ靱性を向上させる作用があるが、
その含有量が５％未満では前記作用に所望の効
果が得られず、一方その含有量が30％を越える
と耐摩耗性が低下するようになることから、そ
の含有量を５〜30％と定めた。
(b) (M)Ｃ・Ｎの含有量
これらの成分には、焼結性を向上させ、かつ
強度を向上させる作用があるが、その含有量が
0.1％未満では前記作用に所望の効果が得られ
ず、一方その含有量が35％を越えると耐摩耗性
が低下するようになることから、その含有量を
0.1〜35％と定めた。
(c) 表面層の平均層厚
表面層は、単相構造の硬質相と結合相からな
る組織を有するものであるが、その平均層厚が
1μｍ未満では所望の切削寿命を確保すること
ができず、一方その平均層厚が10μｍを越える
と、靱性が低下するようになることから、その
平均層厚を１〜10μｍと定めた。
また、表面層は、上記の通り焼結雰囲気を調整
することによつて形成することができるが、その
層厚は、配合組成の全Ｎ／CN比、焼結雰囲気の
昇温過程における窒素雰囲気への切換え温度、並
びに前記窒素雰囲気におけるN2分圧などを制御
することによつて調整することができる。
〔実施例〕
つぎに、この発明のTiCN基サーメツト製切削
工具を実施例により具体的に説明する。
原料粉末として、いずれも１〜1.5μｍの範囲内
の所定の平均粒径を有するTiCN粉末、各種の(M)
Ｃ・Ｎ粉末、Co粉末、およびNi粉末を用意し、
これら原料粉末をそれぞれ第１表に示される配合
組成に配合し、ボールミルにて72時間湿式混合
し、乾燥した後、SNMG432の規格形状にプレス
成形し、ついで、
常温から1100℃までの昇温過程：10-2torrの真
空雰囲気、
1100℃から1350℃までの昇温過程：10torrの
CO2雰囲気、
1350℃から1420〜1500℃の範囲内の所定の焼結
温度までの昇温過程、前記焼結温度に１時間の保
持過程、および前記焼結温度から常温までの冷却
過程：10torrのN2雰囲気、
とした条件で焼結することにより配合組成と実質
的に同じ組成をもち、かつ単相構造の硬質相と結
合相からなる組織の表面層を有する本発明TiCN
基サーメツト製切削チツプ（以下本発明サーメツ
トチツプという）１〜15をそれぞれ製造した。
また、比較の目的で、焼結条件を、
常温から1100℃までの昇温過程：10-2torrの真
空雰囲気、
1100℃から1420〜1500℃の範囲内の所定の焼結
温度までの昇温過程、前記焼結温度に１時間の保
持過程、および前記焼結温度から常温までの冷却
過程：5torrのN2雰囲気、
とする以外は同一の条件で、表面層の形成がない
従来TiCN基サーメツト製切削チツプ（以下従
[Industrial Application Field] This invention is based on titanium carbonitride (hereinafter referred to as TiCN), which exhibits excellent cutting performance over a long period of time, especially when used for heavy cutting such as high-speed cutting, high-feed, and high-depth cutting. ) This relates to a cutting tool made of base cermet. [Conventional technology] Conventionally, in cutting steel, etc., one of Co and Ni was generally used as a binder phase forming component.
Species or two: 5 to 30%, carbides, nitrides, and carbonitrides of metals from Groups 4a, 5a, and 6a of the periodic table as hard phase forming components, and solid solutions of two or more of these (however,
TiCN, as well as nitrides and carbonitrides of group 6a metals are excluded, and the entirety thereof is indicated by (M)C/N,
M represents one or more metals from groups 4a, 5a, and 6a of the periodic table): 0.1 to
35%, and the rest is also a hard phase forming component.
A cutting tool made of TiCN-based cermet is used, which has a composition consisting of TiCN and unavoidable impurities (the above % by weight and the % below indicate weight %). this
The structure of a cutting tool made of TiCN-based cermet consists of a hard phase and a bonding phase, and the hard phase has a double-phase structure (core structure) structure in which the component composition differs between the core part and the outer periphery, or the above-mentioned double-phase structure. It is known to have a single-phase mixed structure with a uniform component composition throughout. [Problems to be solved by the invention] On the other hand, with the recent increase in cutting efficiency,
There is a tendency for high-speed cutting and high-feed cutting to be applied, but the conventional TiCN-based cermet cutting tools mentioned above reach the end of their service life in a relatively short period of time when used for high-speed cutting and high-feed cutting. is the current situation. [Means for Solving the Problems] Therefore, from the above-mentioned viewpoints, the present inventors have developed a cutting tool that exhibits superior cutting performance over a long period of time compared to the conventional TiCN-based cermet cutting tool described above.
As a result of conducting research to obtain cutting tools made of TiCN-based cermet, it was found that in the production of conventional cutting tools made of TiCN-based cermet, the main component, TiCN, was
In order to prevent nitrides and carbonitrides, which are other alloy components, from decomposing and denitrifying, at least the temperature raising process from the denitrification starting temperature to the sintering temperature, the sintering temperature holding process, and the cooling process are necessary. was in a nitrogen atmosphere, but this was changed from room temperature to above the denitrification start temperature.
The heating process to a predetermined temperature within the range of the liquid phase appearance temperature end is performed in a denitrifying atmosphere such as a vacuum or a decarburizing atmosphere containing CO 2 gas, and then the heating process to the remaining sintering temperature, sintering. If the same nitrogen atmosphere is used during the sintering temperature holding process and the cooling process, TiCN after sintering
On the surface of the base cermet, a surface layer consisting of a single-phase hard phase and a binder phase is formed, and titanium carbonitride-based cermet cutting tools with this surface layer can be used for high-speed cutting and high-feeding. They obtained the knowledge that when used for cutting, it exhibits excellent cutting performance over a long period of time. This invention was made based on the above findings, and includes one of Co and Ni as a bonding phase forming component.
Contains one or two types: 5 to 30%, one or two types of (M)C/N as a hard phase forming component: 0.1 to 35%, and the rest is also a hard phase forming component.
TiCN which has a composition consisting of TiCN and inevitable impurities, and whose hard phase has a double phase structure (cored structure) structure or a mixed structure of a double phase structure and a single phase structure.
A TiCN-based cermet cutting tool is characterized in that a surface layer consisting of a single-phase hard phase and a binder phase is formed on the surface of the cermet-based cutting tool with an average layer thickness of 1 to 10 μm. Next, in the cutting tool of this invention, TiCN
The reason why the component composition of the base cermet and the average layer thickness of the surface layer are limited as described above will be explained. (a) Content of Co and Ni These components have the effect of strongly bonding with the dispersed hard phase and improving toughness.
If the content is less than 5%, the desired effect cannot be obtained, while if the content exceeds 30%, the wear resistance will decrease, so the content should be set at 5 to 30%. Established. (b) Content of (M)C/N These components have the effect of improving sinterability and strength, but their content is
If the content is less than 0.1%, the desired effect cannot be obtained, while if the content exceeds 35%, the wear resistance will decrease.
It was set at 0.1-35%. (c) Average layer thickness of the surface layer The surface layer has a single-phase structure consisting of a hard phase and a binder phase.
If the average layer thickness is less than 1 μm, the desired cutting life cannot be ensured, and if the average layer thickness exceeds 10 μm, the toughness will decrease, so the average layer thickness was set at 1 to 10 μm. In addition, the surface layer can be formed by adjusting the sintering atmosphere as described above, but the layer thickness depends on the total N/CN ratio of the compound composition and the nitrogen atmosphere during the temperature rise process of the sintering atmosphere. This can be adjusted by controlling the switching temperature, the N 2 partial pressure in the nitrogen atmosphere, etc. [Example] Next, the TiCN-based cermet cutting tool of the present invention will be specifically explained with reference to Examples. As raw material powder, TiCN powder and various (M) powders each have a predetermined average particle size within the range of 1 to 1.5 μm.
Prepare C/N powder, Co powder, and Ni powder,
Each of these raw material powders was blended into the composition shown in Table 1, wet-mixed in a ball mill for 72 hours, dried, and then press-molded into the standard shape of SNMG432, followed by a heating process from room temperature to 1100℃. : 10 -2 torr vacuum atmosphere, heating process from 1100℃ to 1350℃ : 10torr
CO 2 atmosphere, heating process from 1350°C to a predetermined sintering temperature within the range of 1420 to 1500°C, holding process at the sintering temperature for 1 hour, and cooling process from the sintering temperature to room temperature: 10 torr By sintering in an N 2 atmosphere of
Cutting chips made of base cermet (hereinafter referred to as cermet chips of the present invention) 1 to 15 were manufactured, respectively. For comparison purposes, the sintering conditions are as follows: Temperature raising process from room temperature to 1100℃: 10 -2 torr vacuum atmosphere, temperature increase from 1100℃ to a predetermined sintering temperature within the range of 1420 to 1500℃ A conventional TiCN-based cermet without the formation of a surface layer was prepared under the same conditions except for the process, holding process at the sintering temperature for 1 hour, and cooling process from the sintering temperature to room temperature: 5 torr of N 2 atmosphere. manufactured cutting chips (hereinafter referred to as
【表】【table】
第１表に示される結果から、いずれのサーメツ
トチツプもすぐれた靱性を示すが、本発明サーメ
ツトチツプ１〜15の方が、表面層の形成によつ
て、これの形成がない従来サーメツトチツプ１〜
15に比して、優れた切削性能を示すことが明らか
である。
上述のように、この発明のTiCN基サーメツト
製切削工具は、単相構造の硬質相と結合相からな
る組織を有する表面層の形成によつて断続切削に
すぐれた切削性能を有するばかりでなく、高速切
削や高送り切削に用いてもすぐれた耐摩耗性を示
し、著しく長い使用寿命を示すなど工業上有用な
特性を有するのである。
From the results shown in Table 1, all the thermet chips exhibit excellent toughness, but the thermet chips 1 to 15 of the present invention are superior to the conventional thermet chips 1 to 15, which do not have this formation, due to the formation of a surface layer.
It is clear that this material has superior cutting performance compared to No. 15. As mentioned above, the TiCN-based cermet cutting tool of the present invention not only has excellent cutting performance in interrupted cutting due to the formation of a surface layer having a structure consisting of a single-phase hard phase and a binder phase. It has industrially useful properties such as excellent wear resistance even when used in high-speed cutting and high-feed cutting, and a significantly long service life.
Claims (1)
１種または２種：５〜30％、 硬質相形成成分として周期律表の4a、5a、お
よび6a族金属の炭化物、窒化物、および炭窒化
物、並びにこれらの２種以上の固溶体（ただし炭
窒化チタン、並びに6a族金属の窒化物および炭
窒化物は除く）のうちの１種または２種以上：
0.1〜35％、 を含有し、残りが同じく硬質相形成成分としての
炭窒化チタンと不可避不純物からなる組成（以上
重量％）を有し、 かつ硬質相が、２重相構造（有芯構造）組織、
または２重相構造と単相構造の混合組織を有する
炭窒化チタン基サーメツト製切削工具において、 上記切削工具の表面部に、単相構造の硬質相と
結合相からなる組織を有する表面層を１〜10μｍ
の平均層厚で形成してなる炭窒化チタン基サーメ
ツト製切削工具。[Claims] 1. One or two of Co and Ni as binder phase forming components: 5 to 30%; as hard phase forming components carbides and nitrides of metals from groups 4a, 5a, and 6a of the periodic table; one or more of the following:
0.1 to 35%, with the remainder consisting of titanium carbonitride and unavoidable impurities as hard phase forming components (weight percent), and the hard phase has a double phase structure (cored structure). organization,
Or, in a titanium carbonitride-based cermet cutting tool having a mixed structure of a double-phase structure and a single-phase structure, a surface layer having a structure consisting of a hard phase and a binder phase having a single-phase structure is added to the surface of the cutting tool. ~10μm
A titanium carbonitride-based cermet cutting tool formed with an average layer thickness of .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22607588A JPH0276606A (en) | 1988-09-09 | 1988-09-09 | Cutting tool made of high abrasion-resistant titanium carbide-nitride radical cermet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22607588A JPH0276606A (en) | 1988-09-09 | 1988-09-09 | Cutting tool made of high abrasion-resistant titanium carbide-nitride radical cermet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0276606A JPH0276606A (en) | 1990-03-16 |
| JPH0513762B2 true JPH0513762B2 (en) | 1993-02-23 |
Family
ID=16839423
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22607588A Granted JPH0276606A (en) | 1988-09-09 | 1988-09-09 | Cutting tool made of high abrasion-resistant titanium carbide-nitride radical cermet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0276606A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE519832C2 (en) * | 1999-05-03 | 2003-04-15 | Sandvik Ab | Titanium-based carbonitride alloy with binder phase of cobalt for easy finishing |
| SE519834C2 (en) * | 1999-05-03 | 2003-04-15 | Sandvik Ab | Titanium-based carbonitride alloy with binder phase of cobalt for tough machining |
| JP2014029001A (en) * | 2012-07-31 | 2014-02-13 | Sumitomo Electric Hardmetal Corp | Cermet, method for manufacturing the cermet, and cutting tool |
| JP5900638B2 (en) * | 2012-10-02 | 2016-04-06 | 株式会社タンガロイ | Cermet tool |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54139815A (en) * | 1978-04-24 | 1979-10-30 | Mitsubishi Metal Corp | Sintered hard alloy having hardened surface layer |
| JPS54150411A (en) * | 1978-05-19 | 1979-11-26 | Mitsubishi Metal Corp | Tough thermet having soft surface layer |
| JPS62278267A (en) * | 1986-05-24 | 1987-12-03 | Hitachi Tool Eng Ltd | Surface-coated ticn cermet |
-
1988
- 1988-09-09 JP JP22607588A patent/JPH0276606A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54139815A (en) * | 1978-04-24 | 1979-10-30 | Mitsubishi Metal Corp | Sintered hard alloy having hardened surface layer |
| JPS54150411A (en) * | 1978-05-19 | 1979-11-26 | Mitsubishi Metal Corp | Tough thermet having soft surface layer |
| JPS62278267A (en) * | 1986-05-24 | 1987-12-03 | Hitachi Tool Eng Ltd | Surface-coated ticn cermet |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0276606A (en) | 1990-03-16 |
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