JPH0336254A - Method for hardening surface of titanium-based alloy - Google Patents
Method for hardening surface of titanium-based alloyInfo
- Publication number
- JPH0336254A JPH0336254A JP17117289A JP17117289A JPH0336254A JP H0336254 A JPH0336254 A JP H0336254A JP 17117289 A JP17117289 A JP 17117289A JP 17117289 A JP17117289 A JP 17117289A JP H0336254 A JPH0336254 A JP H0336254A
- Authority
- JP
- Japan
- Prior art keywords
- based alloy
- layer
- titanium
- iron
- alloy layer
- 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.)
- Pending
Links
- 239000000956 alloy Substances 0.000 title claims abstract description 72
- 229910045601 alloy Inorganic materials 0.000 title claims abstract description 71
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 title claims description 39
- 239000010936 titanium Substances 0.000 title claims description 39
- 229910052719 titanium Inorganic materials 0.000 title claims description 39
- 238000000034 method Methods 0.000 title claims description 16
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 62
- 229910052742 iron Inorganic materials 0.000 claims abstract description 31
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 14
- 238000011282 treatment Methods 0.000 claims abstract description 14
- 238000005255 carburizing Methods 0.000 claims description 21
- 238000005121 nitriding Methods 0.000 claims description 18
- 239000010410 layer Substances 0.000 abstract description 44
- 238000009792 diffusion process Methods 0.000 abstract description 6
- 150000004767 nitrides Chemical class 0.000 abstract description 6
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 4
- 239000002344 surface layer Substances 0.000 abstract description 4
- 238000005256 carbonitriding Methods 0.000 abstract 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- 239000007789 gas Substances 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 150000001247 metal acetylides Chemical class 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- 238000007751 thermal spraying Methods 0.000 description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 238000004880 explosion Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 description 2
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 229910000713 I alloy Inorganic materials 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 description 1
- CKUAXEQHGKSLHN-UHFFFAOYSA-N [C].[N] Chemical compound [C].[N] CKUAXEQHGKSLHN-UHFFFAOYSA-N 0.000 description 1
- XMAGQOHRYPDFNV-UHFFFAOYSA-N [C].[N].[N] Chemical compound [C].[N].[N] XMAGQOHRYPDFNV-UHFFFAOYSA-N 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 238000005219 brazing Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000001723 curing Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- -1 oxides Chemical class 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明はチタン基合金の表面硬化処理方法に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for surface hardening treatment of titanium-based alloys.
［従来の技術］
チタン基合金は高比強度林料として最近使用量が増大し
ている。[Prior Art] Titanium-based alloys have recently been increasingly used as forest materials with high specific strength.
しかしチタン基合金は無潤滑の状態で摩擦係数が０．５
〜０．６と大きく、摺動部や他金属との接触部に使用す
る場合、焼付きの問題が生じ、使用上の制約となってい
る。However, titanium-based alloys have a friction coefficient of 0.5 without lubrication.
It has a large value of ~0.6, and when used in sliding parts or parts that come in contact with other metals, the problem of seizure occurs, which is a restriction on use.
この焼付きを防止するには、チタン基合金の表面を硬化
することが必要であり、下記の表面処理方法が“金属チ
タンどその応用“ （昭和５９年７月５日２日刊工業新
聞社発行１頁２７５〜頁２７７）に記載されている。In order to prevent this seizure, it is necessary to harden the surface of the titanium-based alloy, and the following surface treatment method is used in the application of titanium metal etc. (published by Nikkan Kogyo Shimbun on July 5, 1980). 1, pages 275 to 277).
（１〉侵入型元素硬化法
（２〉めっき法
（３）ろう付け、溶射、拡散接合、肉盛溶接法この中で
侵入型元素硬化法は、炭素、酸素、窒素等の侵入型固溶
元素を表面に固溶させるか、又は化合物を生成させて硬
化させる一般的に広く用いられている表面硬化法である
。(1) Interstitial elemental hardening method (2) Plating method (3) Brazing, thermal spraying, diffusion bonding, overlay welding This is a generally widely used surface curing method in which the compound is solid-dissolved on the surface or a compound is formed and hardened.
この侵入型元素硬化法で炭素、酸素を固溶させる場合、
チタンでは表層に多孔質で剥離性の酸化物層を形成しや
すく、従ってこの酸化物層の形威を防止するため、酸素
分圧を厳密にコントロールしながら炭素８酸素の侵入型
元素硬化法を行う必要がある。When carbon and oxygen are dissolved in solid solution using this interstitial element hardening method,
Titanium tends to form a porous and peelable oxide layer on its surface. Therefore, in order to prevent the formation of this oxide layer, an interstitial elemental hardening method using carbon 8 oxygen is used while strictly controlling the oxygen partial pressure. There is a need to do.
又、チタンは炭化物、酸化物１窒化物を形威しやすいた
め、内部へ深いこれらの元素の拡散層を形成させること
が困難であり、従来の方法で得られている酸素拡散層、
窒化層の最大厚さは約５０−であった。In addition, since titanium tends to form carbides, oxides, and nitrides, it is difficult to form deep diffusion layers of these elements inside, and oxygen diffusion layers, which are obtained by conventional methods, are difficult to form.
The maximum thickness of the nitride layer was about 50-.
［発明が解決しようとする課題］
表面性状の良好な表面硬化層をチタン基合金の表面に形
成するには、表層での多孔質で剥離性の酸化物層の形成
を防止する必要があり、このため従来の方法では酸素分
圧を厳密にコントロールする必要がある。[Problems to be Solved by the Invention] In order to form a hardened surface layer with good surface properties on the surface of a titanium-based alloy, it is necessary to prevent the formation of a porous and peelable oxide layer on the surface layer. Therefore, in the conventional method, it is necessary to strictly control the oxygen partial pressure.
又、従来の方法では酸素拡散層、窒化層を内部へ深く形
成するのは困難であり、長時間の処理においても、これ
らの層の得られる最大厚さは約５０１ｔｍであり、例え
ば窒化層３０１１ｍを形威させるのに８５０℃では４０
時間を要する等の問題がある。Furthermore, it is difficult to form an oxygen diffusion layer and a nitride layer deep inside using conventional methods, and even in long-term processing, the maximum thickness that can be obtained for these layers is approximately 501 tm. 40 at 850℃ to make it appear
There are problems such as time required.
本発明は、以上の如き問題点を解決するためのチタン基
合金の表面硬化処理方法を提供することを目的とするも
のである。The object of the present invention is to provide a method for surface hardening treatment of titanium-based alloys to solve the above-mentioned problems.
［課題を解決するための手段］
本発明は、
チタン基合金の表面上に鉄基からなる合金層を形成した
後、浸炭処理又は窒化処理を施すに際し、（ａ）浸炭処
理又は窒化処理前の前記鉄基合金層の炭素含有量を０９
０８重量％以下とする。[Means for Solving the Problems] The present invention provides the following steps when performing carburizing or nitriding after forming an iron-based alloy layer on the surface of a titanium-based alloy: (a) before carburizing or nitriding; The carbon content of the iron-based alloy layer is 09
08% by weight or less.
（ｂ）浸炭処理又は窒化処理後のビッカース硬さが５１
３以上である表面からの深さ（ｔ２）と前記鉄基合金層
の厚み（ｔ１）の比率（ｔ２／１１）を０．８以下とす
る。(b) Vickers hardness after carburizing or nitriding is 51
The ratio (t2/11) of the depth from the surface (t2) which is 3 or more and the thickness (t1) of the iron-based alloy layer is 0.8 or less.
上記（ａ）及び（ｂ）の条件をともに満たすことを特徴
とするチタン基合金の表面硬化方法である。This is a method for surface hardening a titanium-based alloy, characterized by satisfying both conditions (a) and (b) above.
なお本発明のチタン基合金とは、重量において５０％以
上のチタンを含む純チタン、 Ｔｉ−６ＡＩ−４Ｖ合金
、 Ｔｉ−１５Ｖ−３Ｃｒ−３Ｓｎ−３ＡＩ合金等の各
種チタン合金であり、また鉄基合金とは重量において５
０％以上の鉄を含む各種鉄合金をいうものである。The titanium-based alloy of the present invention refers to various titanium alloys such as pure titanium, Ti-6AI-4V alloy, Ti-15V-3Cr-3Sn-3AI alloy, etc. containing 50% or more of titanium by weight, and iron-based Alloy is 5 in weight
It refers to various iron alloys containing 0% or more iron.
［作用］
本発明のチタン基合金の表面硬化方法でのチタン基合金
表面上の鉄基合金層は表面硬化層を得るための必須条件
である。[Function] The iron-based alloy layer on the surface of the titanium-based alloy in the method for surface hardening of a titanium-based alloy of the present invention is an essential condition for obtaining a surface-hardened layer.
チタン基合金に浸炭、窒化処理を施した場合、チタン基
合金中のチタンと炭素、窒素とが反応し炭化物、窒化物
を形成するため、内部に深いこれらの元素の拡散層を形
成させることは困難となる。When carburizing and nitriding a titanium-based alloy, the titanium in the titanium-based alloy reacts with carbon and nitrogen to form carbides and nitrides, so it is impossible to form a deep diffusion layer of these elements inside. It becomes difficult.
しかし、鉄基合金は高温のオーステナイト相で炭素２窒
素の溶解度をもつため、浸炭２窒化処理により容易に表
面硬化層を得ることが出来る。However, since iron-based alloys have carbon dinitrogen solubility in the high-temperature austenite phase, a surface hardening layer can be easily obtained by carburizing dinitriding treatment.
ここで鉄基合金層の形成方法は圧着、爆着、溶射等いず
れの方法でも可能であり、特定の方法によらない。Here, the iron-based alloy layer can be formed by any method such as compression bonding, explosion bonding, thermal spraying, etc., and is not limited to a specific method.
また浸炭、窒化方法として鉄基合金に用いられている従
来の方法の適用が可能であり、例えばガス浸炭法、ガス
窒化法、固体浸炭法の適用が可能である。Furthermore, conventional methods used for iron-based alloys can be used as carburizing and nitriding methods, such as gas carburizing, gas nitriding, and solid carburizing.
従って本発明ではチタン基合金上に鉄基合金層を形威し
、浸炭、窒化処理を施すことが基本的な必要条件である
。Therefore, in the present invention, a basic requirement is to form an iron-based alloy layer on a titanium-based alloy and to perform carburizing and nitriding treatments.
本発明では浸炭、窒化処理前の炭素量が０．０８重量％
以下であることを規定したのは、炭素量が０．０８重量
％以上である場合、浸炭、窒化処理中にチタン基合金層
と鉄基合金層との界面に炭化物を形成し、チタン基合金
層と鉄基合金層どの接合度の低下を招くためである。In the present invention, the amount of carbon before carburizing and nitriding is 0.08% by weight.
The following is specified because if the carbon content is 0.08% by weight or more, carbides are formed at the interface between the titanium-based alloy layer and the iron-based alloy layer during carburizing and nitriding, and the titanium-based alloy This is because the degree of bonding between the iron-based alloy layer and the iron-based alloy layer decreases.
さらに本発明で鉄基からなる合金層厚さ（ｔ１）と硬度
Ｈ≧５１３の浸炭、窒化処理深さ（ｔ２）■
との関係を
１２／１１＜ｏ、８
と規定したのは以下の理由による。Furthermore, in the present invention, the relationship between the iron-based alloy layer thickness (t1) and the carburizing and nitriding depth (t2) with hardness H≧513 is defined as 12/11<o, 8 for the following reasons. by.
つまり浸炭、窒化処理深さが大きくなり、炭素窒素が鉄
基合金層とチタン基合金層との界面まで拡散した場合、
鉄基合金層とチタン基合金層との界面にチタン炭化物、
チタン窒化物を形成し、このため鉄基合金層とチタン基
合金層どの接合度の低下を招くため浸炭、窒化硬化層の
深さを制限するものである。In other words, when the carburizing and nitriding depth increases and carbon nitrogen diffuses to the interface between the iron-based alloy layer and the titanium-based alloy layer,
Titanium carbide is present at the interface between the iron-based alloy layer and the titanium-based alloy layer.
The depth of the carburized and nitrided hardened layer is limited because titanium nitride is formed, which leads to a decrease in the degree of bonding between the iron-based alloy layer and the titanium-based alloy layer.
つまり
ｔ２ ／ ｔ １ ＜ ０．８の条件を
満足する場合には、鉄基合金層とチタン基合金層との界
面までの炭素、窒素の拡散による到達がなく、従って界
面でのチタン炭化物、チタン窒化物の形成に基づく接合
強度の低下を防ぐことが可能となる。In other words, when the condition t2/t1 < 0.8 is satisfied, carbon and nitrogen do not diffuse to the interface between the iron-based alloy layer and the titanium-based alloy layer, and therefore titanium carbide and titanium at the interface do not reach the interface between the iron-based alloy layer and the titanium-based alloy layer. It becomes possible to prevent a decrease in bonding strength due to the formation of nitrides.
次に本発明の実施例について述べる。Next, examples of the present invention will be described.
［実施例］
チタン基合金としてＪＩＳ２種純チタン、 Ｔｌ−６Ａ
Ｉ−４Ｖ合金、 Ｔｌ−１５Ｖ−３Ｃｒ−３Ｓｎ−３Ａ
Ｉ合金、 Ｔｌ−８５Ａ合金を、また鉄基合金としてＳ
ＣＭ８２２相当、 ５ＬＩＳ３０４相当の合金を用意し
、熱間圧延、爆着、溶射によりチタン基合金上に板厚１
ｉｎの鉄基合金層を形成したものを供試材とした。[Example] JIS Class 2 pure titanium, Tl-6A as a titanium-based alloy
I-4V alloy, Tl-15V-3Cr-3Sn-3A
I alloy, Tl-85A alloy, and S as an iron-based alloy.
We prepared alloys equivalent to CM822 and 5LIS304, and applied them to a titanium-based alloy with a thickness of 1 by hot rolling, explosion bonding, and thermal spraying.
A sample material was prepared by forming an iron-based alloy layer.
この時の鉄基合金の炭素量は０．０７〜０．１０重量％
と変化させた。The carbon content of the iron-based alloy at this time is 0.07 to 0.10% by weight
and changed it.
表面硬化処理は上記サンプルを用い、石英ガラス管にサ
ンプルと炭酸ナトリウムを２重量％含む活性炭を封入し
て処理する固体浸炭を行い、さらに滴下式浸炭炉を用い
、浸炭剤としてピロペンゾールを用いたガス浸炭を行い
２次にピット炉を用い、窒化剤としてＮＨ３ガスを流し
てガス窒化処理を行ったが、浸炭温度は９００℃、９５
０℃の２温度、浸炭時間は１〜７時間１窒化温度は５１
０℃。For the surface hardening treatment, the above sample was used, and solid carburization was performed by enclosing the sample and activated carbon containing 2% by weight of sodium carbonate in a quartz glass tube.Furthermore, using a dropping carburizing furnace, gas was applied using pyropenzole as a carburizing agent. Carburizing was carried out and then gas nitriding was carried out using a pit furnace and flowing NH3 gas as a nitriding agent, but the carburizing temperature was 900°C, 95°C
2 temperatures of 0℃, carburizing time 1 to 7 hours, 1 nitriding temperature 51
0℃.
窒化時間は５０〜８０時間とした。The nitriding time was 50 to 80 hours.
表面硬化処理の評価は、ＪＩＳ Ｇ ０５５７に基づく
Ｈｖ≧５１３以上の表面硬化深さとＪＩＳ Ｇ ０６０
１に基づくせん断試験により評価した。Evaluation of surface hardening treatment is based on JIS G 0557, surface hardening depth of Hv≧513 or more, and JIS G 060
Evaluation was made by a shear test based on 1.
表１に行った表面硬化処理条件とその特性を示す。Table 1 shows the conditions of the surface hardening treatment and its characteristics.
本発明を遵守するかぎり、せん断強度１４ｋｇｆ／ｍ＋
ｅ２以上の優れたチタン風合金と表面硬化鉄基合金との
接合特性をもつ表面硬度に優れたチタン基合金が製造さ
れる。As long as the present invention is complied with, shear strength: 14 kgf/m+
A titanium-based alloy with excellent surface hardness and bonding properties between a titanium-like alloy and a surface-hardened iron-based alloy of e2 or higher is produced.
［発明の効果］
本発明のチタン基合金の表面硬化方法によれば、せん断
強度１４ｋｇｆ’／ｍｍ２以上のチタン基合金と鉄基合
金の接合強度をもつ表面硬度の優れたチタン基合金を製
造することが可能となる。[Effects of the Invention] According to the method for surface hardening a titanium-based alloy of the present invention, a titanium-based alloy with excellent surface hardness and a bonding strength between a titanium-based alloy and an iron-based alloy with a shear strength of 14 kgf'/mm2 or more is produced. becomes possible.
手続補正書 （自発） １゜ 事件の表示 特願平１−１７１１７２号 ２゜ 発明の名称 チタン基合金の表面硬化方法 ３゜ 補正をする者 事件との関係 名称 （４］、２）Procedural amendment (spontaneous) 1゜ Display of incidents Patent Application No. 1-171172 2゜ name of invention Surface hardening method for titanium-based alloys 3゜ person who makes corrections Relationship with the incident Name (4), 2)
Claims (1)
炭処理又は窒化処理を施すに際し、（ａ）浸炭処理又は
窒化処理前の前記鉄基合金層の炭素含有量を０．０８重
量％以下とする。 （ｂ）浸炭処理又は窒化処理後のビッカース硬度が５１
３以上である表面からの深さ（ｔ＿ｎ）と前記鉄基合金
層の厚み（ｔ＿１）の比率 （ｔ＿２／ｔ＿１）が０．８以下とする。 上記（ａ）及び（ｂ）の条件をともに満たすことを特徴
とするチタン基合金の表面硬化方法。[Scope of Claims] After forming an iron-based alloy layer on the surface of a titanium-based alloy material, when performing carburizing treatment or nitriding treatment, (a) the carbon content of the iron-based alloy layer before carburizing treatment or nitriding treatment; The amount should be 0.08% by weight or less. (b) Vickers hardness after carburizing or nitriding is 51
The ratio (t_2/t_1) of the depth (t_n) from the surface, which is 3 or more, to the thickness (t_1) of the iron-based alloy layer is 0.8 or less. A method for surface hardening a titanium-based alloy, characterized by satisfying both conditions (a) and (b) above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17117289A JPH0336254A (en) | 1989-07-04 | 1989-07-04 | Method for hardening surface of titanium-based alloy |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17117289A JPH0336254A (en) | 1989-07-04 | 1989-07-04 | Method for hardening surface of titanium-based alloy |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0336254A true JPH0336254A (en) | 1991-02-15 |
Family
ID=15918335
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17117289A Pending JPH0336254A (en) | 1989-07-04 | 1989-07-04 | Method for hardening surface of titanium-based alloy |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0336254A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5699166A (en) * | 1993-11-09 | 1997-12-16 | Seiko Epson Corporation | Copying machine for reproducing an image on a continuous web of labels |
-
1989
- 1989-07-04 JP JP17117289A patent/JPH0336254A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5699166A (en) * | 1993-11-09 | 1997-12-16 | Seiko Epson Corporation | Copying machine for reproducing an image on a continuous web of labels |
| US6040918A (en) * | 1993-11-09 | 2000-03-21 | Sieko Epson Corporation | Copying machine |
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