JP2000337453A - Manufacture of endless metallic belt - Google Patents
Manufacture of endless metallic beltInfo
- Publication number
- JP2000337453A JP2000337453A JP11151924A JP15192499A JP2000337453A JP 2000337453 A JP2000337453 A JP 2000337453A JP 11151924 A JP11151924 A JP 11151924A JP 15192499 A JP15192499 A JP 15192499A JP 2000337453 A JP2000337453 A JP 2000337453A
- Authority
- JP
- Japan
- Prior art keywords
- endless metal
- metal belt
- treatment
- belt
- thickness
- 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
Landscapes
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、無段変速機の動力
伝達ベルトに用いられる無端状金属ベルトの製造方法に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an endless metal belt used for a power transmission belt of a continuously variable transmission.
【０００２】[0002]
【従来の技術】Ｖ溝間隔を変換できる１対のプーリと、
両プーリ間に張設された動力伝達ベルトからなる無段変
速機が知られている。前記無段変速機では、前記動力伝
達ベルトとして複数の無端状金属ベルトを重ね合わせた
状態で保持したものが用いられている。2. Description of the Related Art A pair of pulleys capable of changing a V groove interval,
A continuously variable transmission including a power transmission belt stretched between both pulleys is known. In the continuously variable transmission, a power transmission belt in which a plurality of endless metal belts are held in an overlapping state is used.
【０００３】前記無端状金属ベルトは、前記プーリ間を
走行するときには直線状態を呈する一方、前記プーリに
沿って走行するときには湾曲状態を呈し、前記直線状態
と湾曲状態との繰り返しによる過酷な曲げ変形が加えら
れる。そこで、前記無端状金属ベルトは、前記過酷な曲
げ変形に耐える強度を備えることが必要とされる。The endless metal belt exhibits a linear state when traveling between the pulleys, and exhibits a curved state when traveling along the pulleys, and severe bending deformation due to repetition of the linear state and the curved state. Is added. Therefore, the endless metal belt is required to have strength enough to withstand the severe bending deformation.
【０００４】従来、前記過酷な曲げ変形に耐える強度を
備える材料としてマルエージング鋼が知られている。前
記マルエージング鋼は、１７〜１９％のＮｉの他、Ｃ
ｏ，Ｍｏ，Ｔｉを含む低炭素鋼であり、溶体化後、適温
に加熱することによりマルテンサイト状態において時効
硬化を生じ、高強度、高靱性を兼ね備える超強力鋼であ
るので、前記無端状金属ベルトに賞用される。Conventionally, maraging steel has been known as a material having the strength to withstand the severe bending deformation. The maraging steel contains 17-19% Ni and C
It is a low-carbon steel containing o, Mo, and Ti. It is an ultra-strength steel having age hardening in a martensitic state by heating to an appropriate temperature after solution treatment and having both high strength and high toughness. Awarded belt.
【０００５】前記無端状金属ベルトは、前記マルエージ
ング鋼の薄板の端部同士を溶接してリング状に形成した
後、所定の長さに圧延することにより形成されている。
しかし、前記動力伝達ベルト用無端状金属ベルトに用い
る場合には、さらに、耐摩耗性、耐疲労強度を備えるこ
とが望まれるので、前記マルエージング鋼に表面硬化処
理を施すことが行われている。[0005] The endless metal belt is formed by welding the ends of the thin maraging steel sheet to form a ring shape and then rolling it to a predetermined length.
However, when it is used for the endless metal belt for a power transmission belt, it is desired to further have abrasion resistance and fatigue resistance. Therefore, a surface hardening treatment is performed on the maraging steel. .
【０００６】前記表面硬化処理は、一般に、前記リング
状に形成したマルエージング鋼を所定の長さに圧延して
形成した無端状金属ベルトに、溶体化処理、周長補正、
時効処理を施した後、ガス窒化処理、ガス軟窒化処理ま
たは塩浴窒化処理を施すことにより行われる。前記ガス
窒化処理は、前記時効処理を施した無端状金属ベルト
を、アンモニアガス雰囲気中に５００〜５５０℃の処理
温度で５０〜１００時間保持するものであり、前記ガス
軟窒化処理は、ガス窒化処理のアンモニアガスに替えて
アンモニアガスとＲＸガスとの混合雰囲気を用いるもの
である。In general, the surface hardening treatment is performed by subjecting an endless metal belt formed by rolling the ring-shaped maraging steel to a predetermined length to a solution treatment, a circumference correction,
After the aging treatment, the aging treatment is performed by performing a gas nitriding treatment, a gas nitrocarburizing treatment, or a salt bath nitriding treatment. In the gas nitriding treatment, the endless metal belt subjected to the aging treatment is maintained in an ammonia gas atmosphere at a treatment temperature of 500 to 550 ° C. for 50 to 100 hours. A mixed atmosphere of ammonia gas and RX gas is used in place of the ammonia gas for the treatment.
【０００７】また、前記塩浴窒化処理は、シアン化カリ
ウム（ＫＣＮ）またはシアン化ナトリウム（ＮａＣＮ）
を主剤とし、これらが空気と反応して生じるシアン酸カ
リウム（ＫＣＮＯ）またはシアン酸ナトリウム（ＮａＣ
ＮＯ）を含む溶融塩中に、前記時効処理を施した無端状
金属ベルトを浸漬するものであり、前記溶融塩の商品名
を取ってタフトライド法と呼ばれる。前記塩浴窒化処理
は、通常、１〜２％のＣＮ- と、３１〜３５％のＣＮＯ
- とを含む前記溶融塩を５７０〜５８０℃の温度に加熱
して、該溶融塩中に前記無端状金属ベルトを所定時間浸
漬することにより行われる。Further, the salt bath nitriding treatment is performed by using potassium cyanide (KCN) or sodium cyanide (NaCN).
And potassium cyanate (KCNO) or sodium cyanate (NaC
The aging-treated endless metal belt is immersed in a molten salt containing NO), and the trade name of the molten salt is called a tuftride method. The salt bath nitriding is usually carried out with 1 to 2% of CN - and 31 to 35% of CNO.
- the molten salt containing the heated to a temperature of five hundred and seventy to five hundred eighty ° C., is carried out by the fact that the endless metal belt is immersed a predetermined time in the molten salt.
【０００８】前記表面硬化処理によれば、いずれの方法
によっても、前記無端状金属ベルトの表面に窒化層を形
成して硬化させ、耐摩耗性及び耐疲労強度を向上させる
ことができる。According to the above-mentioned surface hardening treatment, a nitride layer is formed on the surface of the endless metal belt and hardened by any of the methods, thereby improving wear resistance and fatigue resistance.
【０００９】ところで、前記一般的なガス窒化処理また
はガス軟窒化処理では前記無端状金属ベルトの表面に窒
化層を形成するために長時間を要するとの問題がある。
また、前記塩浴窒化処理では、処理温度が高温であるた
めに、前記マルエージング鋼が過時効になるとの問題が
ある。そこで、前記時効処理と窒化処理とを同時に行う
ことが提案されている。However, in the general gas nitriding or gas nitrocarburizing, there is a problem that it takes a long time to form a nitride layer on the surface of the endless metal belt.
Further, in the salt bath nitriding treatment, since the treatment temperature is high, there is a problem that the maraging steel is overaged. Therefore, it has been proposed to perform the aging treatment and the nitriding treatment at the same time.
【００１０】例えば、特開昭６２−２２４６６５号公報
には、前記窒化処理に要する時間を短縮するために、レ
トルト内滞留時間を６００〜３６００秒（分解率１〜６
％）としたアンモニアガスの雰囲気中に、４２０〜４７
０℃の処理温度で、前記無端状金属ベルトを１〜６時間
保持するガス窒化処理方法が開示されている。前記公報
には、処理温度が４５０℃以上であれば、前記窒化処理
と同時に時効処理を行うことができることが記載されて
いる。For example, Japanese Patent Application Laid-Open No. 62-224665 discloses that in order to shorten the time required for the nitriding treatment, the residence time in the retort is set to 600 to 3600 seconds (decomposition rate 1 to 6).
%) In an atmosphere of ammonia gas.
A gas nitriding method for holding the endless metal belt at a processing temperature of 0 ° C. for 1 to 6 hours is disclosed. The publication states that if the processing temperature is 450 ° C. or higher, the aging treatment can be performed simultaneously with the nitriding treatment.
【００１１】また、本出願人の出願になる特開平１０−
１２１１３０号公報には、１〜２％のＣＮ- と、３１〜
３５％のＣＮＯ- とを含む前記溶融塩を５２０〜５３０
℃の温度に加熱して、該溶融塩中に前記無端状金属ベル
トを１０〜２５分間浸漬する塩浴窒化処理方法が開示さ
れている。前記公報に記載の塩浴窒化処理方法によれ
ば、前記圧延後の無端状金属ベルトに直ちに、塩浴窒化
処理を施すことができ、溶体化処理、周長補正、時効処
理を省略することができる。すなわち、前記塩浴窒化処
理と同時に時効処理を施すことができる。Further, Japanese Patent Application Laid-Open No.
No. 121130 discloses that 1 to 2% of CN - and 31 to 31%
35% of CNO - the molten salt containing the 520-530
A salt bath nitriding method in which the endless metal belt is immersed in the molten salt for 10 to 25 minutes by heating to a temperature of 0 ° C. is disclosed. According to the salt bath nitriding method described in the publication, the endless metal belt after the rolling can be subjected to the salt bath nitriding process immediately, and the solution treatment, the circumference correction, and the aging treatment can be omitted. it can. That is, the aging treatment can be performed simultaneously with the salt bath nitriding treatment.
【００１２】しかしながら、前記窒化処理はいずれの方
法においても熱処理を伴うので、前記無端状金属ベルト
に熱処理歪みを生じて該無端状金属ベルトの周長が変化
するとの不都合がある。However, since the nitriding treatment involves a heat treatment in any method, there is a disadvantage that the heat treatment distortion occurs in the endless metal belt and the circumferential length of the endless metal belt changes.
【００１３】[0013]
【発明が解決しようとする課題】本発明は、かかる不都
合を解消して、優れた寸法安定性を備える無端状金属ベ
ルトの製造方法を提供することを目的とする。SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing an endless metal belt having excellent dimensional stability by solving such disadvantages.
【００１４】[0014]
【課題を解決するための手段】前記マルエージング鋼製
の無端状金属ベルトに時効処理及び窒化処理を施すと、
該無端状金属ベルトの表層部では窒化層が形成されるた
めに体積が膨張する傾向を示し、該無端状金属ベルトの
内部では時効により体積が収縮する傾向を示す。この結
果、前記無端状金属ベルトは組織の安定状態を維持する
ために、周長変化等の寸法変化を来すものと考えられ
る。When the maraging steel endless metal belt is subjected to aging treatment and nitriding treatment,
The surface of the endless metal belt tends to expand in volume due to the formation of a nitrided layer, and the inside of the endless metal belt tends to contract in volume due to aging. As a result, it is considered that the endless metal belt undergoes a dimensional change such as a change in circumference in order to maintain a stable state of the tissue.
【００１５】前記無端状金属ベルトの表層部の膨張と、
内部の収縮とは、前記窒化処理の種類によっても傾向が
異なり、例えばガス窒化処理またはガス軟窒化処理で
は、内部の収縮の方が表層部の膨張よりも大きく、全体
としては周長が短縮される傾向を示す。また、塩浴窒化
処理では、反対に表層部の膨張の方が内部の収縮よりも
大きく、全体としては周長が延長される傾向を示す。The expansion of the surface layer of the endless metal belt;
The internal shrinkage tends to differ depending on the type of the nitriding treatment.For example, in a gas nitriding treatment or a gas nitrocarburizing treatment, the internal shrinkage is larger than the expansion of the surface layer portion, and the circumference is shortened as a whole. Show a tendency to On the contrary, in the salt bath nitriding treatment, the expansion of the surface layer is larger than the internal contraction, and the circumference tends to be extended as a whole.
【００１６】本発明者らは、前記目的を達成するため
に、前記無端状金属ベルトの表層部に形成される窒化層
の厚さと、周長の変化との関係について種々検討を重ね
た。この結果、前記窒化層の厚さを、該無端状金属ベル
トの厚さ全体に対して特定の割合とすることにより、ガ
ス窒化処理またはガス軟窒化処理であるか塩浴窒化処理
であるかを問わず、優れた寸法安定性が得られることを
見出した。The present inventors have conducted various studies on the relationship between the thickness of the nitride layer formed on the surface layer of the endless metal belt and the change in the perimeter in order to achieve the above object. As a result, by setting the thickness of the nitrided layer to a specific ratio with respect to the entire thickness of the endless metal belt, whether the gas nitriding treatment, the gas soft nitriding treatment, or the salt bath nitriding treatment is performed. Regardless, it has been found that excellent dimensional stability can be obtained.
【００１７】そこで、本発明の無端状金属ベルト製造方
法は、マルエージング鋼の鋼板の端部同士を溶接してリ
ング状に形成し、所定の長さに圧延した後、時効処理及
び窒化処理を施して、無段変速機の動力伝達ベルトに用
いられる無端状金属ベルトを製造する方法において、該
窒化処理は、該無端状金属ベルトの表面に形成される窒
化層の厚さが該無端状金属ベルトの厚さ全体の２０〜４
０％になるように行うことを特徴とする。Therefore, in the method for producing an endless metal belt according to the present invention, the ends of a steel sheet of maraging steel are welded to form a ring, rolled to a predetermined length, and then subjected to an aging treatment and a nitriding treatment. In the method for producing an endless metal belt used for a power transmission belt of a continuously variable transmission, the nitriding treatment is performed by reducing a thickness of a nitrided layer formed on a surface of the endless metal belt. 20-4 of the entire belt thickness
It is characterized in that it is performed so as to be 0%.
【００１８】本発明の製造方法によれば、前記窒化層の
厚さを、前記無端状金属ベルトの厚さ全体に対して２０
〜４０％になるようにすることにより、該無端状金属ベ
ルトの表層部の窒化層形成による膨張と、内部の時効に
よる収縮とが釣り合い、周長の変化を極く小さくするこ
とができる。前記窒化層の厚さが前記無端状金属ベルト
の厚さ全体の２０％未満のときには、内部の時効による
収縮の作用が大きくなり、周長が短縮される傾向が顕著
になる。また、前記窒化層の厚さが前記無端状金属ベル
トの厚さ全体の４０％を超えるときには、表層部の窒化
層形成による膨張の作用が大きくなり、周長が延長され
る傾向が顕著になる。According to the manufacturing method of the present invention, the thickness of the nitride layer is set to be 20 to the entire thickness of the endless metal belt.
By setting it to 40%, the expansion due to the formation of the nitride layer on the surface layer of the endless metal belt and the shrinkage due to aging inside are balanced, and the change in the circumference can be made extremely small. When the thickness of the nitrided layer is less than 20% of the entire thickness of the endless metal belt, the effect of shrinkage due to internal aging becomes large, and the tendency for the perimeter to be shortened becomes prominent. Further, when the thickness of the nitrided layer exceeds 40% of the entire thickness of the endless metal belt, the effect of the expansion due to the formation of the nitrided layer on the surface layer increases, and the tendency of the perimeter to be extended becomes prominent. .
【００１９】本発明の製造方法によれば、前記の様に、
周長の変化が極く小さく優れた寸法安定性が得られるの
で、この結果として所定の引張強度及び耐疲労強度を確
保することができる。According to the production method of the present invention, as described above,
Since the change in the circumference is extremely small and excellent dimensional stability can be obtained, predetermined tensile strength and fatigue resistance can be ensured as a result.
【００２０】[0020]
【発明の実施の形態】次に、添付の図面を参照しながら
本発明の実施の形態についてさらに詳しく説明する。図
１は本実施形態の製造方法により得られた無端状金属ベ
ルトの構成を示す説明的断面図、図２は無端状金属ベル
トの窒化層の厚さの該ベルト全体の厚さに対する割合と
周長の変化との関係を示すグラフ、図３は無端状金属ベ
ルトの窒化層の厚さの該ベルト全体の厚さに対する割合
と引張強度との関係を示すグラフ、図４は無端状金属ベ
ルトの窒化層の厚さの該ベルト全体の厚さに対する割合
と耐疲労強度との関係を示すグラフである。Next, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 is an explanatory cross-sectional view showing the configuration of an endless metal belt obtained by the manufacturing method of the present embodiment, and FIG. 2 is a diagram showing the ratio of the thickness of the nitride layer of the endless metal belt to the overall thickness of the belt and the circumference FIG. 3 is a graph showing the relationship with the change in length, FIG. 3 is a graph showing the relationship between the ratio of the thickness of the nitrided layer of the endless metal belt to the total thickness of the belt and the tensile strength, and FIG. 4 is a graph showing a relationship between a ratio of a thickness of a nitride layer to a thickness of the entire belt and fatigue resistance.
【００２１】本実施形態に用いるマルエージング鋼は、
Ｃが０．０３％以下、Ｓｉが０．１０％以下、Ｍｎが
０．１０％以下、Ｐが０．０１％以下、Ｓが０．０１％
以下の低炭素鋼であり、１８〜１９％のＮｉ、４．７〜
５．２％のＭｏ、０．０５〜０．１５％のＡｌ、０．５
０〜０．７０％のＴｉ、８．５〜９．５％のＣｏを含む
１８％のＮｉ鋼である。The maraging steel used in the present embodiment is:
C is 0.03% or less, Si is 0.10% or less, Mn is 0.10% or less, P is 0.01% or less, and S is 0.01%.
The following low carbon steels, 18-19% Ni, 4.7-
5.2% Mo, 0.05-0.15% Al, 0.5
18% Ni steel with 0-0.70% Ti, 8.5-9.5% Co.
【００２２】本実施形態の製造方法では、まず、前記組
成を有するマルエージング鋼の薄板をベンディングして
ループ化したのち、端部を溶接して円筒状体を形成す
る。次に、これを真空炉中、８２０〜８３０℃に２０〜
６０分間保持して溶体化処理する。前記溶体化処理によ
り、結晶を再配列し、溶接歪を除去することができる。In the manufacturing method of the present embodiment, first, a thin plate of maraging steel having the above composition is bent to form a loop, and then the ends are welded to form a cylindrical body. Next, this is heated in a vacuum furnace to 820 to 830 ° C. for 20 to
Hold for 60 minutes to perform solution treatment. By the solution treatment, the crystals can be rearranged and welding distortion can be removed.
【００２３】次に、前記円筒状体を所定の幅に切断し、
リング状体を形成する。前記リング状体は前記切断によ
り、その端部にエッジが立っているので、バレル研磨に
より面取りしたのち、圧下率４０〜５０％で冷間圧延
し、無端状金属ベルトを形成する。Next, the cylindrical body is cut into a predetermined width,
Form a ring. Since the ring-shaped body has an edge at the end by the cutting, the ring-shaped body is chamfered by barrel polishing, and then cold-rolled at a rolling reduction of 40 to 50% to form an endless metal belt.
【００２４】次に、前記無端状金属ベルトに時効処理及
び窒化処理を施し、図１示のように、表層部に窒化層
１，１が形成され、内部が時効層２となっている無端状
金属ベルト３を得る。図１示の無端状金属ベルト３にお
いて、窒化層１の厚さをｔ1 ，ｔ2 、無端状金属ベルト
３全体の厚さをＴとすると、窒化層１の厚さの無端状金
属ベルト３の厚さ全体に対する割合Ａ（％）は、下式
（１）で表わされる。Next, the endless metal belt is subjected to an aging treatment and a nitriding treatment, and as shown in FIG. The metal belt 3 is obtained. In the endless metal belt 3 shown in FIG. 1, assuming that the thickness of the nitrided layer 1 is t 1 and t 2 , and the total thickness of the endless metal belt 3 is T, the thickness of the endless metal belt 3 is the same as that of the nitrided layer 1. Is expressed by the following equation (1).
【００２５】 Ａ＝（ｔ1 ＋ｔ2 ）／Ｔ×１００ ・・・（１） 本実施形態の製造方法では、Ａが２０〜４０％の範囲に
なるように、前記時効処理及び窒化処理を施す。前記時
効処理及び窒化処理は、具体的には、次のようにして行
う。A = (t 1 + t 2 ) / T × 100 (1) In the manufacturing method of the present embodiment, the aging treatment and the nitriding treatment are performed so that A is in the range of 20 to 40%. . The aging treatment and the nitriding treatment are specifically performed as follows.
【００２６】まず、前記窒化処理として、ガス窒化処理
またはガス軟窒化処理を行う場合には、前記冷間圧延を
施した無端状金属ベルトを、時効処理室と、ガス窒化処
理室またはガス軟窒化処理室とが連続して設けられた処
理装置に導入する。前記処理装置では、例えば、雰囲気
温度が４８０℃に維持されている時効処理室と、同温に
維持されているガス窒化処理室またはガス軟窒化処理室
とが、扉を隔てて連続して設けられている。前記ガス窒
化処理室にはアンモニアガス及び窒素ガスが流通され、
ガス軟窒化処理室にはアンモニアガス及びＲＸガスが流
通される。First, when a gas nitriding treatment or a gas nitrocarburizing treatment is performed as the nitriding treatment, the cold-rolled endless metal belt is subjected to an aging treatment chamber, a gas nitriding treatment chamber or a gas nitrocarburizing treatment. The processing chamber is introduced into a processing device provided continuously. In the processing apparatus, for example, an aging treatment chamber in which the ambient temperature is maintained at 480 ° C., and a gas nitriding treatment chamber or a gas nitrocarburizing treatment chamber maintained at the same temperature are provided continuously with a door interposed therebetween. Have been. Ammonia gas and nitrogen gas flow through the gas nitriding chamber,
Ammonia gas and RX gas flow through the gas nitrocarburizing chamber.
【００２７】前記処理装置に導入された前記無端状金属
ベルトは、前記時効処理室で所定時間の時効処理が施さ
れた後、前記扉を開けて、前記ガス窒化処理室またはガ
ス軟窒化処理室に移動される。前記無端状金属ベルトが
移動されたならば、前記扉が閉じられ、所定時間のガス
窒化処理またはガス軟窒化処理が施される。After the endless metal belt introduced into the processing apparatus is subjected to aging treatment for a predetermined time in the aging treatment chamber, the door is opened and the gas nitriding treatment chamber or the gas nitrocarburizing treatment chamber is opened. Moved to When the endless metal belt is moved, the door is closed, and gas nitriding or gas nitrocarburizing is performed for a predetermined time.
【００２８】本実施形態では、前記無端状金属ベルト
は、前記処理装置内に例えば３００分保持され、そのう
ち後半の６０〜９０分を前記ガス窒化処理室またはガス
軟窒化処理室内に保持することにより、前記窒化層１の
割合Ａが２０〜４０％の範囲になる。In the present embodiment, the endless metal belt is held in the processing apparatus for, for example, 300 minutes, and the latter 60 to 90 minutes is held in the gas nitriding chamber or the gas nitrocarburizing chamber. The ratio A of the nitride layer 1 is in the range of 20 to 40%.
【００２９】次に、前記窒化処理として、塩浴窒化処理
を行う場合には、前記冷間圧延を施した無端状金属ベル
トを、ＫＣＮまたはＮａＣＮ等のシアン化物、ＫＣＮＯ
またはＮａＣＮＯ等のシアン酸塩、Ｋ2 ＣＯ3 またはＮ
ａ2 ＣＯ3 等の炭酸塩からなる溶融塩に浸漬する。前記
溶融塩は、例えば、１〜２％のＣＮ- と、３１〜３５％
のＣＮＯ- とを含む。Next, in the case of performing a salt bath nitriding treatment as the nitriding treatment, the endless metal belt subjected to the cold rolling is treated with a cyanide such as KCN or NaCN, KCNO.
Or cyanate such as NaCNO, K 2 CO 3 or N
a Dipped in a molten salt made of a carbonate such as a 2 CO 3 . The molten salt comprises, for example, 1 to 2% of CN - and 31 to 35%
Of CNO - and a.
【００３０】本実施形態では、例えば５２０℃に加熱し
た前記溶融塩に、前記無端状金属ベルトを１０〜３５分
間浸漬することにより、前記窒化層１の割合Ａが２０〜
４０％の範囲になる。In the present embodiment, the endless metal belt is immersed in, for example, the molten salt heated to 520 ° C. for 10 to 35 minutes so that the ratio A of the nitrided layer 1 is 20 to 35.
It is in the range of 40%.
【００３１】次に、窒化層１の厚さの無端状金属ベルト
３の厚さ全体に対する割合Ａ（％）と、無端状金属ベル
ト３の周長との関係を図２に示す。図２から、窒化層１
の割合Ａが２０％のときには周長が０．１ｍｍ短縮され
るに過ぎず、４０％のときには周長が０．６ｍｍ延長さ
れるに過ぎないことが分かる。従って、図２から窒化層
１の割合Ａが２０〜４０％の範囲にあることにより、無
端状金属ベルト３の周長の変化が極く小さく、優れた寸
法安定性が得られることが明らかである。Next, FIG. 2 shows the relationship between the ratio A (%) of the thickness of the nitride layer 1 to the entire thickness of the endless metal belt 3 and the circumference of the endless metal belt 3. From FIG. 2, the nitride layer 1
It can be seen that when the ratio A is 20%, the circumference is reduced only by 0.1 mm, and when the ratio A is 40%, the circumference is only extended by 0.6 mm. Therefore, it is apparent from FIG. 2 that when the ratio A of the nitrided layer 1 is in the range of 20 to 40%, the change in the circumferential length of the endless metal belt 3 is extremely small, and excellent dimensional stability can be obtained. is there.
【００３２】無端状金属ベルト３は、図１示のように、
表層部に窒化層１，１が形成され、内部が時効層２とな
っており、無段変速機の動力伝達ベルトに用いるために
は時効層２による引張強度及び靱性と、窒化層１の硬度
による耐疲労強度とが共に適正な範囲にあることが望ま
れる。無端状金属ベルト３を前記無段変速機の動力伝達
ベルトに用いるには、例えば２００ｋｇｆ／ｍｍ2 以上
の引張強度と、例えば破断するまでの耐久回数が平均応
力１２２ｋｇｆ／ｍｍ2 で１×１０4 回以上の耐疲労強
度とを備えることが必要とされる。本実施形態の無端状
金属ベルト３では、窒化層１の厚さの無端状金属ベルト
３の厚さ全体に対する割合Ａ（％）が前記範囲にあるの
で、無段変速機の動力伝達ベルトとして所要の引張強度
と耐疲労強度との両方を満足させることができる。The endless metal belt 3 is, as shown in FIG.
The nitrided layers 1 and 1 are formed on the surface layer, and the inside is an aging layer 2. For use in a power transmission belt of a continuously variable transmission, the tensile strength and toughness of the aging layer 2 and the hardness of the nitrided layer 1 are provided. It is desired that both the fatigue strength and the fatigue strength of the steel are within an appropriate range. In order to use the endless metal belt 3 for the power transmission belt of the continuously variable transmission, for example, the tensile strength of 200 kgf / mm 2 or more and the number of times of endurance before breaking are 1 × 10 4 with an average stress of 122 kgf / mm 2. It is required to have fatigue resistance of more than one time. In the endless metal belt 3 of the present embodiment, since the ratio A (%) of the thickness of the nitrided layer 1 to the entire thickness of the endless metal belt 3 is in the above range, it is required as a power transmission belt of the continuously variable transmission. Can satisfy both tensile strength and fatigue resistance.
【００３３】次に、窒化層１の厚さの無端状金属ベルト
３の厚さ全体に対する割合Ａ（％）と、無端状金属ベル
ト３の引張強度との関係を図３に示す。図３から明らか
なように、窒化層１の割合Ａが２０〜４０％の範囲にあ
ることにより、無端状金属ベルト３の引張強度を２００
ｋｇｆ／ｍｍ2 以上とすることができる。FIG. 3 shows the relationship between the ratio A (%) of the thickness of the nitride layer 1 to the entire thickness of the endless metal belt 3 and the tensile strength of the endless metal belt 3. As is clear from FIG. 3, when the ratio A of the nitrided layer 1 is in the range of 20 to 40%, the tensile strength of the endless metal belt 3 is set to 200.
kgf / mm 2 or more.
【００３４】次に、窒化層１の厚さの無端状金属ベルト
３の厚さ全体に対する割合Ａ（％）と、無端状金属ベル
ト３の耐疲労強度との関係を図４に示す。図４では、無
端状金属ベルト３を無段階変速機の動力伝達ベルトに使
用したときに、破断するまでの耐久回数を指標として、
耐疲労強度を示す。図４から、ガス窒化処理またはガス
軟窒化処理の場合には窒化層１の割合Ａが２０％以上に
なると耐久回数が急激に向上し、塩浴窒化処理の場合に
は窒化層１の割合Ａが４０％以下になると耐久回数が急
激に向上することが分かる。従って図４から、窒化層１
の割合Ａが２０〜４０％の範囲にあることにより、無端
状金属ベルト３の耐疲労強度を著しく向上できることが
明らかである。Next, FIG. 4 shows the relationship between the ratio A (%) of the thickness of the nitride layer 1 to the entire thickness of the endless metal belt 3 and the fatigue resistance of the endless metal belt 3. In FIG. 4, when the endless metal belt 3 is used for a power transmission belt of a continuously variable transmission, the number of endurances before breaking is used as an index.
Shows fatigue resistance. From FIG. 4, it can be seen that in the case of the gas nitriding treatment or the gas nitrocarburizing treatment, when the ratio A of the nitrided layer 1 becomes 20% or more, the number of times of durability is sharply increased, and in the case of the salt bath nitriding treatment, the ratio A of the nitrided layer 1 is increased. It can be seen that when the value is 40% or less, the number of endurance times sharply increases. Therefore, from FIG.
It is clear that when the ratio A is in the range of 20 to 40%, the fatigue resistance of the endless metal belt 3 can be significantly improved.
【図１】本発明の製造方法により得られた無端状金属ベ
ルトの構成を示す説明的断面図FIG. 1 is an explanatory sectional view showing a configuration of an endless metal belt obtained by a manufacturing method of the present invention.
【図２】無端状金属ベルトの窒化層の厚さの該ベルト全
体の厚さに対する割合と周長の変化との関係を示すグラ
フ。FIG. 2 is a graph showing a relationship between a ratio of a thickness of a nitride layer of an endless metal belt to a thickness of the entire belt and a change of a circumference.
【図３】無端状金属ベルトの窒化層の厚さの該ベルト全
体の厚さに対する割合と引張強度との関係を示すグラ
フ。FIG. 3 is a graph showing a relationship between a ratio of a thickness of a nitrided layer of an endless metal belt to a thickness of the entire belt and tensile strength.
【図４】無端状金属ベルトの窒化層の厚さの該ベルト全
体の厚さに対する割合と耐疲労強度との関係を示すグラ
フ。FIG. 4 is a graph showing the relationship between the ratio of the thickness of the nitrided layer of the endless metal belt to the thickness of the entire belt and the fatigue resistance.
１…窒化層、 ３…無端状金属ベルト。 1 ... nitride layer, 3 ... endless metal belt.
Claims (1)
してリング状に形成し、所定の長さに圧延した後、時効
処理及び窒化処理を施して、無段変速機の動力伝達ベル
トに用いられる無端状金属ベルトを製造する方法におい
て、 該窒化処理は、該無端状金属ベルトの表面に形成される
窒化層の厚さが該無端状金属ベルトの厚さ全体の２０〜
４０％になるように行うことを特徴とする無端状金属ベ
ルトの製造方法。1. A power transmission belt for a continuously variable transmission, wherein the ends of a maraging steel plate are welded to form a ring, rolled to a predetermined length, and then subjected to aging treatment and nitriding treatment. In the method for producing an endless metal belt used in the method, the nitriding treatment is performed such that a thickness of a nitrided layer formed on a surface of the endless metal belt is 20 to a total thickness of the endless metal belt.
A method for producing an endless metal belt, wherein the production is performed so as to be 40%.
Priority Applications (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11151924A JP2000337453A (en) | 1999-05-31 | 1999-05-31 | Manufacture of endless metallic belt |
| EP00304503A EP1055739B1 (en) | 1999-05-28 | 2000-05-26 | Method of manufacturing laminated ring and molten salt composition for use in such method |
| DE60043035T DE60043035D1 (en) | 1999-05-28 | 2000-05-26 | Process for producing laminated rings and heat treatment apparatus for use in this process |
| EP09168510A EP2119800A1 (en) | 1999-05-28 | 2000-05-26 | Method of manufacturing laminated ring and heat treatment apparatus for use in such method |
| DE60042630T DE60042630D1 (en) | 1999-05-28 | 2000-05-26 | Process for producing laminated rings and molten salt composition for use in this process |
| US09/578,692 US6379473B1 (en) | 1999-05-28 | 2000-05-26 | Method of manufacturing laminated ring using molten salt composition |
| US09/580,920 US6631542B1 (en) | 1999-05-28 | 2000-05-26 | Method of manufacturing laminated ring and heat treatment apparatus for use in such method |
| EP00304504A EP1055738B1 (en) | 1999-05-28 | 2000-05-26 | Method of manufacturing laminated ring and heat treatment apparatus for use in such method |
| US10/036,424 US6663724B2 (en) | 1999-05-28 | 2002-01-07 | Molten salt composition for use in manufacturing laminated rings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11151924A JP2000337453A (en) | 1999-05-31 | 1999-05-31 | Manufacture of endless metallic belt |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000337453A true JP2000337453A (en) | 2000-12-05 |
Family
ID=15529186
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11151924A Pending JP2000337453A (en) | 1999-05-28 | 1999-05-31 | Manufacture of endless metallic belt |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000337453A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004029320A1 (en) | 2002-09-24 | 2004-04-08 | Honda Giken Kogyo Kabushiki Kaisha | Method of nitriding metal ring and apparatus therefor |
| WO2011043648A1 (en) | 2009-10-06 | 2011-04-14 | Robert Bosch Gmbh | Drive belt provided with a laminated set of steel rings |
| WO2011076397A1 (en) | 2009-12-23 | 2011-06-30 | Robert Bosch Gmbh | Drive belt provided with a steel ring |
| WO2013095089A1 (en) | 2011-12-23 | 2013-06-27 | Robert Bosch Gmbh | Flexible steel ring and drive belt provided with a laminated set of such rings |
| CN112692521A (en) * | 2020-12-23 | 2021-04-23 | 吉林建筑大学 | Fine processing method for connecting node based on assembly type steel structure |
| CN114484089A (en) * | 2022-01-25 | 2022-05-13 | 北京科技大学 | Inner surface axial diameter bidirectional gradient reinforced steel pipe and preparation method thereof |
| CN115008135A (en) * | 2022-06-21 | 2022-09-06 | 湖南华菱湘潭钢铁有限公司 | Production method of large-wall-thickness large-caliber longitudinal submerged arc welded pipe L555M |
-
1999
- 1999-05-31 JP JP11151924A patent/JP2000337453A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004029320A1 (en) | 2002-09-24 | 2004-04-08 | Honda Giken Kogyo Kabushiki Kaisha | Method of nitriding metal ring and apparatus therefor |
| WO2011043648A1 (en) | 2009-10-06 | 2011-04-14 | Robert Bosch Gmbh | Drive belt provided with a laminated set of steel rings |
| WO2011076397A1 (en) | 2009-12-23 | 2011-06-30 | Robert Bosch Gmbh | Drive belt provided with a steel ring |
| WO2013095089A1 (en) | 2011-12-23 | 2013-06-27 | Robert Bosch Gmbh | Flexible steel ring and drive belt provided with a laminated set of such rings |
| CN112692521A (en) * | 2020-12-23 | 2021-04-23 | 吉林建筑大学 | Fine processing method for connecting node based on assembly type steel structure |
| CN114484089A (en) * | 2022-01-25 | 2022-05-13 | 北京科技大学 | Inner surface axial diameter bidirectional gradient reinforced steel pipe and preparation method thereof |
| CN114484089B (en) * | 2022-01-25 | 2023-01-24 | 北京科技大学 | Inner surface axial diameter bidirectional gradient reinforced steel pipe and preparation method thereof |
| CN115008135A (en) * | 2022-06-21 | 2022-09-06 | 湖南华菱湘潭钢铁有限公司 | Production method of large-wall-thickness large-caliber longitudinal submerged arc welded pipe L555M |
| CN115008135B (en) * | 2022-06-21 | 2023-05-26 | 湖南华菱湘潭钢铁有限公司 | Production method of large-wall-thickness large-caliber longitudinal submerged arc welded pipe L555M |
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