JPH02154834A - Manufacture of metal belt for power transmission - Google Patents
Manufacture of metal belt for power transmissionInfo
- Publication number
- JPH02154834A JPH02154834A JP30826288A JP30826288A JPH02154834A JP H02154834 A JPH02154834 A JP H02154834A JP 30826288 A JP30826288 A JP 30826288A JP 30826288 A JP30826288 A JP 30826288A JP H02154834 A JPH02154834 A JP H02154834A
- Authority
- JP
- Japan
- Prior art keywords
- residual stress
- belt
- compressive residual
- nitriding
- treatment
- 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
- 239000002184 metal Substances 0.000 title claims abstract description 18
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 18
- 230000005540 biological transmission Effects 0.000 title claims description 15
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 230000035882 stress Effects 0.000 claims abstract description 102
- 238000000034 method Methods 0.000 claims abstract description 24
- 230000032683 aging Effects 0.000 claims abstract description 22
- 239000007788 liquid Substances 0.000 claims abstract description 16
- 238000005507 spraying Methods 0.000 claims abstract description 14
- 238000011282 treatment Methods 0.000 claims description 40
- 239000002245 particle Substances 0.000 claims description 28
- 239000012530 fluid Substances 0.000 claims description 18
- 239000000203 mixture Substances 0.000 claims description 3
- 238000005121 nitriding Methods 0.000 abstract description 34
- 229910000831 Steel Inorganic materials 0.000 abstract description 15
- 239000010959 steel Substances 0.000 abstract description 15
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 10
- 238000002156 mixing Methods 0.000 abstract description 7
- 229910001240 Maraging steel Inorganic materials 0.000 abstract description 5
- 230000006835 compression Effects 0.000 abstract description 3
- 238000007906 compression Methods 0.000 abstract description 3
- 229910052698 phosphorus Inorganic materials 0.000 abstract description 3
- 239000002994 raw material Substances 0.000 abstract 1
- 238000005480 shot peening Methods 0.000 description 14
- 230000007423 decrease Effects 0.000 description 13
- 239000010410 layer Substances 0.000 description 11
- 239000000463 material Substances 0.000 description 8
- 238000012545 processing Methods 0.000 description 8
- 238000007796 conventional method Methods 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 238000005452 bending Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 239000011521 glass Substances 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000005096 rolling process Methods 0.000 description 4
- 238000005482 strain hardening Methods 0.000 description 4
- 238000005255 carburizing Methods 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 229910052759 nickel Inorganic materials 0.000 description 3
- 239000003921 oil Substances 0.000 description 3
- 235000019198 oils Nutrition 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 239000007921 spray Substances 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 101100136092 Drosophila melanogaster peng gene Proteins 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 239000010687 lubricating oil Substances 0.000 description 2
- 239000006104 solid solution Substances 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 229910000997 High-speed steel Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000003483 aging Methods 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 238000001192 hot extrusion Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910000765 intermetallic Inorganic materials 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 235000010446 mineral oil Nutrition 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000004881 precipitation hardening Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000007779 soft material Substances 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 235000015112 vegetable and seed oil Nutrition 0.000 description 1
- 239000008158 vegetable oil Substances 0.000 description 1
- 230000003245 working effect Effects 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、自動車の自動変速機や種々の産業機械等に使
用される動力伝達用金属ベルトの製造方法、およびその
方法によって製造された動力伝達用金属ベルトに関する
。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for manufacturing a metal belt for power transmission used in automatic transmissions of automobiles and various industrial machines, and a method for manufacturing power transmission belts used in automatic transmissions of automobiles and various industrial machines, and Related to transmission metal belts.
（従来の技術〕
近年、自動車の自動変速機においては、ＣＶＴベルトの
如き金属製ベルトを使用した無段変速機が使用され始め
ている。ここで使用される動力伝達用金属ベルトには、
高靭性、高硬度とともに優れた加工性および疲労強度・
寿命が要求される。(Prior Art) In recent years, continuously variable transmissions using metal belts such as CVT belts have begun to be used in automatic transmissions for automobiles.The metal belts for power transmission used here include:
High toughness and hardness as well as excellent workability and fatigue strength.
Long life is required.
そのため、このベルトには、疲労強度・寿命を化学的、
物理的に高めたマルエージ鋼が一般に用いられている。Therefore, the fatigue strength and lifespan of this belt is determined by
Physically enhanced marage steels are commonly used.
マルエージ鋼の疲労強度・寿命を高めるための手段とし
ては、素材中の介在物を減少させる「化学的な手段」と
、ベルト表面への圧縮残留応力を付与する「物理的な手
段」が有効とされている。Effective means to increase the fatigue strength and life of marage steel are "chemical means" that reduce inclusions in the material, and "physical means" that apply compressive residual stress to the belt surface. has been done.
しかし、前者の「化学的な手段」では大きな効果が期待
できないので、通常は後者の「物理的な手段」に重点が
おかれている。後者の「物理的な手段」 （圧縮残留応
力付与手段）は更に、ｒ浸炭、窒化１といった表面硬化
による冶金的手段と、ｒ塑性変形」、ｒショットピーニ
ング１といった機械的手段とに分類できる。However, since the former ``chemical means'' cannot be expected to have great effects, the emphasis is usually placed on the latter ``physical means.'' The latter "physical means" (compressive residual stress imparting means) can be further classified into metallurgical means by surface hardening such as r-carburizing and nitriding1, and mechanical means such as r-plastic deformation and r-shot peening1.
「物理的な手段」 （圧縮残留応力付与手段）について
具体例をあげて説明すると、例えば、特開昭５３−４２
１７２号公報には、ローラによる曲げでベルト表層にｒ
塑性変形１で圧縮残留応力を付加する方法が開示されて
いる。また、特開昭６２−１９２５２８号公報には、溶
体化処理、「塑性変形１による圧縮応力付与、時効を兼
ねたｒ窒化Ｊ（４８０’Ｃ）を順に行って、表面圧縮残
留応力を付与する方法が開示されている。しかし、いず
れの方法によっても、疲労強度・寿命は満足なレベルに
達しない。To explain the "physical means" (compressive residual stress imparting means) with specific examples, for example, JP-A-53-42
No. 172 discloses that r is applied to the belt surface layer by bending with a roller.
A method of applying compressive residual stress during plastic deformation 1 is disclosed. In addition, JP-A No. 62-192528 describes that solution treatment, "applying compressive stress by plastic deformation 1, and r-nitriding J (480'C) which also serves as aging are performed in order to impart surface compressive residual stress. Several methods have been disclosed. However, none of these methods achieves a satisfactory level of fatigue strength and life.
本発明者が考える満足なレベルとは、両＠換算応力振幅
７５ ｋｇ ｆ ／Ｍ”での回転試験でベルトが破断す
るまでの繰り返し回数が５００万回以上であり、そのた
めにベルトの表面に付与されなければならない圧縮残留
応力は、後で詳しく述べるが、外表面については１５０
ｋｇｆ／ｍ”以上、内表面についても１２０ ｋｇ ｆ
／ａｒｍ”以上であることが、本発明者の研究から明
らかとなっている。The satisfactory level that the inventor considers is that the number of repetitions until the belt breaks in a rotation test at a converted stress amplitude of 75 kg f / M" is 5 million times or more, and for that reason, the amount of stress applied to the surface of the belt is The compressive residual stress that must be applied to the outer surface is 150
kgf/m” or more, and 120 kgf for the inner surface
/arm'' or more has become clear from research by the present inventor.
（発明が解決しようとする課題）
このような観点から上記従来技術を見ると、前者の特開
昭５３−４２１７２号公報に開示されたｒ塑性変形１で
得られる圧縮残留応力は、付与加工度に限度があるため
、高々ｌｏｏｋｇｆ／ｍ”にしかならない、しかも、こ
の場合は内表面側の残留応力が引張応力側に移行するた
め、たとえ逆方向に曲げを加えても内外表面ともにその
圧縮残留応力を１００ ｋｇ ｒ ／ｍ”以上にするこ
とは困難である。(Problems to be Solved by the Invention) Looking at the above-mentioned prior art from this perspective, the compressive residual stress obtained by r plastic deformation 1 disclosed in the former Japanese Patent Application Laid-Open No. 53-42172 is Since there is a limit to the bending force, the maximum value is "look f/m".Moreover, in this case, the residual stress on the inner surface side shifts to the tensile stress side, so even if bending is applied in the opposite direction, the compressive residual stress on both the inner and outer surfaces will be reduced. It is difficult to increase the stress to 100 kg r /m'' or more.
一方、ｒ浸炭・窒化ｊでは、ベルトの内外表面にともに
圧縮残留応力を与えることは可能であるが、残留応力レ
ベルを高めるために表面のＣ，Ｎ壷を多くすると、表面
に脆化層が生じ、かえって疲労強度・寿命が低下する。On the other hand, in carburizing and nitriding, it is possible to apply compressive residual stress to both the inner and outer surfaces of the belt, but if the number of C and N pots on the surface is increased to increase the residual stress level, a brittle layer is formed on the surface. This results in a decrease in fatigue strength and life.
特開昭６２−１９２５２８号に開示された方法は、ｒ塑
性変形ｊとｒ窒化１を採用するものの、ここで得られる
圧縮残留応力は、窒化処理後の表面硬度を高くすれば、
１６０ｋｇｆ ／ａｍ”にも達するが、表面に脆化層を
生じ、疲労破壊以前に回転曲げ中に脆性破断が生じる０
表面に脆化層が生じないようにしようとすると、表面硬
度を８６０８ｖ以下に抑える必要があり、そうした場合
は、ｒ窒化１のみで圧縮残留応力は３０〜６０ｋｇｆ／
蘭ｆにしか過ぎず、窒化前にｒ塑性変形」を加えても圧
縮機残留応力を１２０ｋｇｆ ７ｇ１ｍ”に到達させる
ことはできない。Although the method disclosed in JP-A-62-192528 employs r plastic deformation j and r nitriding 1, the compressive residual stress obtained here can be reduced by increasing the surface hardness after nitriding.
160kgf/am”, but a brittle layer is formed on the surface, and brittle fracture occurs during rotary bending before fatigue fracture occurs.
In order to prevent a brittle layer from forming on the surface, it is necessary to suppress the surface hardness to 8608 V or less, and in such a case, the compressive residual stress will be 30 to 60 kgf/
The compressor residual stress cannot reach 120kgf7g1m'' even if ``plastic deformation'' is applied before nitriding.
疲労強度の高い１８％Ｎｉマルエージ鋼を例にとって更
に詳しく説明すると、０．０５ Ｃ−０，０４Ｓｉ−０
，０３３Ｍｎ−０，００７Ｐ−０，００２Ｓ−１８，３
Ｎ＋−８，７Ｃｏ−０，６５Ｔｉ−０，０７Ａｊ２−０
． ＯＯ２Ｎのものは、４７５〜４９０’ＣＸ３ ｈｒ
の時効でビッカース硬さは５００〜５５０Ｈｖになる。To explain in more detail using 18% Ni maraging steel with high fatigue strength as an example, 0.05 C-0,04Si-0
,033Mn-0,007P-0,002S-18,3
N+-8,7Co-0,65Ti-0,07Aj2-0
．． OO2N is 475-490'CX3 hr
The Vickers hardness becomes 500 to 550 Hv after aging.
更に、表面に脆化層を形成させることなくｒ窒化１を施
すと、表面硬度は７８０〜８６０ Ｈｖになる。この表
面硬度では圧縮残留応力は３０〜６０ｋｇｆ／ｍ’にし
か過ぎない、そこでｒ窒化ｊで表面硬度を９５０〜１０
００Ｈｖにすると、圧縮残留応力は１００ｋｇｆ／■８
に向上するが、それと引き換えに表面は詭化し、回転試
験中に疲労破壊ではなく脆性破壊を生じる。また、ｒ窒
化１前にｒ塑性変形１を加えても、表面脆化なしでは圧
縮残留応力が１２０ ｋｇ ｒ ／ｒＩＩｎ”に達する
ことばない。Furthermore, when r-nitriding 1 is performed without forming an embrittled layer on the surface, the surface hardness becomes 780 to 860 Hv. With this surface hardness, the compressive residual stress is only 30 to 60 kgf/m', so the surface hardness is increased to 950 to 10 by nitriding.
At 00Hv, the compressive residual stress is 100kgf/■8
However, at the cost of this, the surface becomes rougher and brittle fracture occurs instead of fatigue fracture during the rotation test. Furthermore, even if 1 r plastic deformation is applied before 1 nitriding, the compressive residual stress will never reach 120 kg r /rIIn'' without surface embrittlement.
他方、ｒショットピーニングｊは、広い意味ではｒ塑性
変形１に含まれる圧縮残留応力付与手段である。特開昭
６２−１９２５２８号公報にも、その「塑性変形１がｒ
ショットピーニング」に代替えできることが明らかにさ
れている。このｒショットピーニング１は、−船釣には
ステンレス鋼、Ａ２合金などの軟質材料に対して、ガラ
ス球やアルミナを投射させる形で実施されている。しか
し、ガラス球の場合は、金属製ベルトの如き硬質材に対
しては、衝突時に破壊を生じ、圧縮残留応力の増大に寄
与しないばかりでなく、表面に疵を付ける。そして、何
よりも、金属製ベルトの圧縮残留応力付与に有効であっ
たとしても、それが広い意味でｒ塑性変形１に含まれる
以上は、それ単独でベルトの内外表面に１２０ｋｇｆ／
ｍ”以上の圧縮残留応力を付与することは不可能であり
、また、従来の組合せ技術をもってしても同様である。On the other hand, the r-shot peening j is a compressive residual stress imparting means included in the r-plastic deformation 1 in a broad sense. JP-A No. 62-192528 also states that “plastic deformation 1 is r
It has been revealed that it can be used as an alternative to "shot peening." This r-shot peening 1 is carried out in the form of projecting a glass ball or alumina onto a soft material such as stainless steel or A2 alloy for boat fishing. However, in the case of a glass bulb, when it collides with a hard material such as a metal belt, it breaks, and not only does it not contribute to an increase in compressive residual stress, but also causes scratches on the surface. Above all, even if it is effective in imparting compressive residual stress to a metal belt, as long as it is included in r plastic deformation 1 in a broad sense, it alone will cause 120 kgf/
It is impossible to impart a compressive residual stress of more than m'', and the same is true even with conventional combination techniques.
従って、両振換算応力振幅７５ｋｇｆ／■１での回転試
験でベルトが破断するまでの繰り返し回数が５ＯＯ万回
以上という前述した疲労強度・寿命についての目標は達
成されない。Therefore, the above-mentioned target for fatigue strength and life of 500,000 or more repetitions until the belt breaks in a rotation test at a double-conversion stress amplitude of 75 kgf/1 is not achieved.
本発明は、上記目標を達成できる動力伝達用金属ベルト
の製造方法、およびその方法によって製造された上記目
標達成の動力伝達用金属ベルトを提供することを目的と
する。An object of the present invention is to provide a method for manufacturing a metal belt for power transmission that can achieve the above goals, and a metal belt for power transmission that achieves the above goals manufactured by the method.
ところで、前記特開昭６２−１９２５２８号公報には、
前述したように、広い意味でのｒ塑性変形１とｒ窒化１
とを組合せた圧縮残留応力付与手段が開示されている。By the way, in the above-mentioned Japanese Patent Application Laid-open No. 192528/1983,
As mentioned above, r plastic deformation 1 and r nitriding 1 in a broad sense
A compressive residual stress applying means is disclosed that combines the following.
単独で十分な圧縮ＩＡ留応力が確保できない以上、この
組合せという思想は有効と考えられる。しかし、表面に
脆化層が形成されない程度のｒ窒化１では、ｒ塑性変形
ｊと組合されても内外表面の圧縮残留応力は１００ｋｇ
ｆ／鵬１程度であり、ｒ窒化１単独では３０〜６０ｋｇ
ｆ／鍾８に過ぎないことは、前述したとおりである。The idea of this combination is considered to be effective as long as sufficient compressive IA retention stress cannot be ensured by either method alone. However, in r-nitriding 1, where no brittle layer is formed on the surface, the compressive residual stress on the inner and outer surfaces is 100 kg even when combined with r-plastic deformation j.
f/Peng is about 1, and r nitriding 1 alone is 30 to 60 kg.
As mentioned above, it is only f/8.
本発明者は、その原因を■のように解析し、その結果、
■の知見を得た。The inventor analyzed the cause as shown in ■, and as a result,
■We obtained the following knowledge.
■ 前記特開昭６２−１９２５２８号公報に開示されて
いる圧縮残留応力付与手段では、ｒ塑性変形ｊによる圧
縮残留応力付与後、時効を兼ねたｒ窒化１を行っている
。ｒ窒化１前に残留応力を付与すると、ｒ窒化１は加速
されるものの、処理時間が短くなり過ぎ、処理効果がバ
ッチ単位で大きく変動する。また、ｒ窒化ｊ前に付与し
た圧縮残留応力がｒ窒化１により緩和されてしまう。更
に、時効と「窒化」とを同時に行っているが、ここで採
用されている処理温度（４８０”以下）では十分な時効
硬化を得ることができず、圧縮残留応力が不足する。こ
のようなことから、「塑性変形１とｒ窒化１とを組み合
わせるにもかかわらず、圧縮残留応力は十分に付与され
ない。(2) In the compressive residual stress imparting means disclosed in JP-A-62-192528, after imparting compressive residual stress by r plastic deformation j, r-nitriding 1 which also serves as aging is performed. If residual stress is applied before r-nitriding 1, r-nitriding 1 will be accelerated, but the treatment time will be too short and the treatment effect will vary greatly from batch to batch. Moreover, the compressive residual stress applied before r-nitriding is relaxed by r-nitriding 1. Furthermore, although aging and "nitriding" are performed simultaneously, sufficient age hardening cannot be obtained at the treatment temperature employed here (480" or less), resulting in insufficient compressive residual stress. Therefore, "despite combining plastic deformation 1 and r-nitriding 1, compressive residual stress is not sufficiently applied.
■ これに対し、予め時効処理を行って十分な析出硬化
を得た後にｒ窒化ｊ等で表面硬化を行と、ｒ窒化１は遅
れるが、処理時間が十分制御できるようになり、圧縮残
留応力は安定する。それでも、表面に脆化層を形成させ
ないようにとすると、得られる圧縮残留応力は３０〜６
０ｋｇｆ／■２である。そこで、表面硬化後に更に「塑
性変形１を行うと、表面硬化までに得た圧縮残留応力は
緩和されず、表面硬化までに得た圧縮残留応力にｒ塑性
変形１で得た圧縮残留応力がそのまま相乗される。■ On the other hand, if surface hardening is performed with r-nitriding after obtaining sufficient precipitation hardening by performing aging treatment in advance, r-nitriding 1 will be delayed, but the treatment time will be fully controllable and the compressive residual stress will be reduced. becomes stable. However, if we try not to form a brittle layer on the surface, the resulting compressive residual stress is 30 to 6
It is 0 kgf/■2. Therefore, if plastic deformation 1 is further performed after surface hardening, the compressive residual stress obtained before surface hardening will not be relaxed, and the compressive residual stress obtained during plastic deformation 1 will remain in the compressive residual stress obtained before surface hardening. Synergized.
また、表面硬化層は延性があるため、ショットピーニン
グによっても割れの生じる心配がない、従って、ｒ塑性
変形１だけでは、高々１００ｋｇｆ／ｍ”でしかない圧
縮残留応力も、ｒ塑性変形１の前に時効、ｒ窒化１等を
順番に行っておくことにより、最終的には圧縮残留応力
を１２０ ｋｇ ｆ ／ａｍ”以上にできる。In addition, since the surface hardening layer is ductile, there is no risk of cracking even when shot peening is performed. Therefore, with r-plastic deformation 1 alone, compressive residual stress of only 100 kgf/m" can be reduced even before r-plastic deformation 1. By sequentially performing aging, r-nitriding, etc., the compressive residual stress can finally be increased to 120 kg f /am'' or more.
また、■の知見とは別に、次のような知見を本発明者は
得ている。Furthermore, in addition to the finding (2), the present inventor has obtained the following finding.
■ 疲労強度・寿命についての前記目標を達成するため
には、ベルト表面に１２０ｋｇｆｌ閤２の圧縮残留応力
を付与することが必要であるが、ベルト外表面に残留応
力を付与するだけでは前記目標は達成されない、前記目
標達成のためにはベルト内表面にも同等の圧縮残留応力
が必要である０例えば、内表面の圧縮残留応力が８０
ｋｇ ｆ ７ｍ”では、外面の圧縮残留応力がいくら高
くても、前記目標は達成されない。■ In order to achieve the above goals regarding fatigue strength and service life, it is necessary to apply a compressive residual stress of 120 kgfl2 to the belt surface, but it is not possible to achieve the above goals by simply applying residual stress to the belt outer surface. In order to achieve the above target, an equivalent compressive residual stress is required on the inner surface of the belt. For example, if the compressive residual stress on the inner surface is 80
kg f 7 m'', this goal is not achieved no matter how high the compressive residual stress on the outer surface.
■ 特開昭５３−４２１７２号公報や特開昭６２−１９
２５２８号公報に示されているローラ曲げによるｒ塑性
変形１で圧縮残留応力を得た場合、内面側の残留応力は
引張応力の側に移行するので、たとえ１２０ｋｇｆ／ｍ
”の圧縮残留応力が得られたとしても、前記目標は達成
されない、前記目標達成のためには、内外面ともに圧縮
残留応力を付与し得るｒｔｐｌ性変形１手段が必要であ
り、圧縮残留応力レベルとしては、外表面については１
５０ｋｇｆ／閣３以上、内表面については１２０ｋｇｆ
／鵬２以上である。■ JP-A-53-42172 and JP-A-62-19
When compressive residual stress is obtained by r plastic deformation 1 due to roller bending as shown in Publication No. 2528, the residual stress on the inner surface side shifts to the tensile stress side, so even if it is 120 kgf/m
Even if a compressive residual stress of As for the outer surface, 1
50kgf/cabinet 3 or higher, 120kgf for inner surface
/ Peng is 2 or higher.
■ 内外面ともに圧縮残留応力を付与できる手段として
は、ｒショットピーニングｊがあり、なかでも特にアル
ミナ等の難破損性粒子に水等の液体を媒体として組合せ
たものが効果的である。これによると、粒子衝突時の衝
撃が緩和され、また粒子間の衝突が防止され、その結果
、粒子の破壊が防止され、ベルト内外面に十分な圧縮残
留応力が付与される。しかも、壊れた粒子が液流により
べルト表面から除去され、ベルト表面の疵発生が防止さ
れる。空気を媒体とした場合は、アルミナでさえ粒子間
の衝突とベルト表面への衝突とにより粒子の保有する運
動エネルギーが損失し、また、衝突により壊れた粒子が
ベルト表面に残留し、ベルト使用時にその表面に疵を付
ける。(2) As a means for applying compressive residual stress to both the inner and outer surfaces, shot peening is available, and among these, a combination of hard-to-break particles such as alumina and a liquid such as water as a medium is particularly effective. According to this, the impact at the time of particle collision is alleviated, collision between particles is prevented, and as a result, destruction of the particles is prevented, and sufficient compressive residual stress is imparted to the inner and outer surfaces of the belt. Moreover, the broken particles are removed from the belt surface by the liquid flow, thereby preventing the occurrence of flaws on the belt surface. When air is used as a medium, even alumina particles lose their kinetic energy due to collisions between particles and collisions with the belt surface, and particles broken due to collisions remain on the belt surface, causing problems when the belt is used. Scratch the surface.
■ 難破損性粒子に液体を組合せたｒシロットビーニグ
１によると、圧延やその後の熱処理で生じた微小な表面
疵も除去され、これもベルトの疲労強度・寿命に好影響
を与える。また、ベルト表面には０．２〜１μｍ程度の
ミクロ的な凹凸が形成され、これがベルトを重ねて使用
する場合に潤滑油の油溜として機能し、これも又、ベル
トの疲労強度・寿命に好結果をもたらす。(2) According to the r-Shirott Beenig 1, which combines hard-to-break particles with a liquid, minute surface flaws caused by rolling and subsequent heat treatment are also removed, which also has a positive effect on the belt's fatigue strength and service life. In addition, microscopic irregularities of approximately 0.2 to 1 μm are formed on the belt surface, and these function as oil reservoirs for lubricating oil when belts are stacked, which also affects the belt's fatigue strength and service life. Brings good results.
本発明の製造方法は、以上の知見に基づき開発されたも
ので、時効処理後に表面硬化処理を受けた金属ベルトの
内外表面に、難破損性粒子と液体との混合流体を吹き付
ける方法である。The manufacturing method of the present invention was developed based on the above findings, and is a method in which a mixed fluid of unbreakable particles and liquid is sprayed onto the inner and outer surfaces of a metal belt that has undergone surface hardening treatment after aging treatment.
また、本発明の金属ベルトは、この方法によって製造さ
れた外表面１５０ｋｇｆ／ｍ”以上、内裏面１２０ ｋ
ｇ ｆ ７ｍ”以上の各圧縮残留応力を保有するベルト
である。Furthermore, the metal belt of the present invention manufactured by this method has an outer surface of 150 kgf/m or more and an inner back surface of 120 kgf/m.
The belt has a compressive residual stress of 7 m'' or more.
時効処理後にｒ窒化１等の表面硬化処理を行うことによ
り、時効処理時間が十分に制御され、圧縮残留応力が安
定する。これらの処理の後にｒショットピーニング１を
行うことにより、時効処理、表面硬化処理で得られた圧
縮残留応力に、ｒショットピーニング１による圧ｔｉ残
留応力がそのまま相乗される。破壊損性粒子に流体を組
合せた「ショットピーニング」は、単にその衝突衝撃に
よってベルト内外面に圧縮残留応力を付与するだけでな
（、ショット後にベルト表面に残留する粒子を除去する
とともに、圧延や熱処理段階で生じた表面疵を除去し、
更にミクロ的な油溜をベルト表面に形成し、これらの相
乗によりベルトの疲労強度・寿命を著しく改善する。そ
の結果、表面硬化処理において、表面脆化を生じさせる
ことなく、ベルト表面に１２０ｋｇｆ／鋪２以上、更に
は１５０ｋｇｆ／鵬容以上の圧縮残留応力の付与を可能
ならしめる。By performing a surface hardening treatment such as r-nitriding 1 after the aging treatment, the aging treatment time can be sufficiently controlled and the compressive residual stress can be stabilized. By performing r-shot peening 1 after these treatments, the pressure Ti residual stress due to r-shot peening 1 is directly added to the compressive residual stress obtained by the aging treatment and surface hardening treatment. "Shot peening", which combines fracture-damaging particles with fluid, not only applies compressive residual stress to the inner and outer surfaces of the belt due to the impact impact (but also removes particles remaining on the belt surface after shot, and Removes surface flaws caused during the heat treatment stage,
Furthermore, microscopic oil pockets are formed on the belt surface, and the synergistic effect of these effects significantly improves the fatigue strength and life of the belt. As a result, in the surface hardening treatment, it is possible to impart a compressive residual stress of 120 kgf/space or more, and even 150 kgf/space or more, to the belt surface without causing surface embrittlement.
本発明のベルトは、外表面に１５０ｋｇｆ／ｍ”の圧縮
残留応力を有し、内表面にも１２０ｋｇｆ／鴎８以上の
圧縮残留応力を保有し、両県換算応力振幅７５ ｋｇ
ｆ ７ｍ”での回転試験における破断までの繰り返し回
数は５００万回以上に達する。The belt of the present invention has a compressive residual stress of 150 kgf/m" on the outer surface, and a compressive residual stress of 120 kgf/m" or more on the inner surface, with a stress amplitude of 75 kg converted to both prefectures.
The number of repetitions until breakage in the rotation test at f 7 m" reaches more than 5 million times.
第１図は、この繰り返し回数と圧縮残留応力との関係を
本発明法および従来法について示したグラフである。い
ずれも前述した１８％Ｎ＋マルエージ鋼を対象とし、従
来法では時効を兼ねた「窒化ｊ後、ローラ曲げによるｒ
ｌ性変形１で圧縮残留応力付与を行い、本発明法では時
効、ｒ窒化１を順番に行った後、表面に球状アルミナと
水との混合流体を吹き付けるｒショットピーニング１を
行った。FIG. 1 is a graph showing the relationship between the number of repetitions and the compressive residual stress for the method of the present invention and the conventional method. In both cases, the above-mentioned 18%N+ marage steel is targeted, and in the conventional method, after nitriding, which also serves as aging, r
In the method of the present invention, aging and r-nitriding 1 were performed in order, and then r-shot peening 1 was performed in which a mixed fluid of spherical alumina and water was sprayed onto the surface.
従来法では、圧縮残留応力は最大で１２０ｋｇｆ／ｍ”
であり、そのときの繰り返し回数は２０万回である。こ
れに対し、本発明法では、圧縮残留応力は１２０ｋｇｆ
／ｍ”以上が可能であり、１５０ ｋｇ ｆ ／ｗａｓ
”をも超えている。また、残留応力が１２０ ｋｇ ｆ
７ｍ”の場合の操り返し回数を従来法と本発明法とで
比較すると、従来法では２０万回であるのに対し、本発
明法では２００万回を超えている。これは、本発明法で
採用されているｒショットピーニング１、すなわち難破
損性粒子と液体との混合流体によるｒショットピーニン
グ１が、単に圧縮残留応力を高めるだけでなく、疲労破
壊の起点となる圧延や熱処理で生じた微小な表面疵を取
り除き、その一方でベルト表面に油溜となるミクロ的な
凹凸を付与し、これらが疲労強度・寿命の改善に効果的
に寄与しているためである。With the conventional method, the maximum compressive residual stress is 120 kgf/m”
The number of repetitions at that time is 200,000 times. In contrast, in the method of the present invention, the compressive residual stress is 120 kgf
/m” or more is possible, and 150 kg f /was
In addition, the residual stress exceeds 120 kg f
Comparing the number of repetitions in the case of 7 m'' between the conventional method and the method of the present invention, it is 200,000 times with the conventional method, while it is over 2 million times with the method of the present invention. R-shot peening 1, which is used in R-shot peening 1 using a mixed fluid of hard-to-break particles and liquid, not only increases compressive residual stress, but also reduces stress caused by rolling and heat treatment, which is the starting point of fatigue fracture. This is because it removes minute surface flaws and at the same time imparts microscopic irregularities that become oil pockets on the belt surface, which effectively contributes to improving fatigue strength and life.
以下に本発明の代表的な実施の態様について説明する。 Typical embodiments of the present invention will be described below.
Ｏ素材鋼およびその加工法
本発明において用いることのできる素材鋼は、この種の
金属ベルトに供されるマルエージ鋼であればいずれもよ
いが、特に以下に示す成分組成からなるマルエージ鋼を
素材鋼とするのが好ましい。O material steel and its processing method The material steel that can be used in the present invention may be any marage steel that is used for this type of metal belt, but in particular marage steel having the composition shown below may be used as the material steel. It is preferable that
すなわち、ＣｊＯ，０１％以下、Ｓｊ：０．０５％以下
、Ｍｎ：０．０５％以下、Ｐ：０．００８％以下、Ｓ：
０．００４％以下、Ｎｉ：１５〜１９％、Ｃ。That is, CjO, 01% or less, Sj: 0.05% or less, Mn: 0.05% or less, P: 0.008% or less, S:
0.004% or less, Ni: 15-19%, C.
：８〜１５％、Ｍｏ：３．Ｏ〜５．５％、Ｔｉ：０．４
〜１．５％、／ｌ：０．０５〜０．１５％、Ｎ：０．０
０５％以下を含有し、残部不可避不純物およびＦｅから
なるマルエージ鋼である。:8-15%, Mo:3. O ~ 5.5%, Ti: 0.4
~1.5%, /l: 0.05~0.15%, N: 0.0
It is a maraging steel containing 0.05% or less of Fe, with the remainder consisting of unavoidable impurities and Fe.
なお、各成分の限定理由は次に述べる通りである。Note that the reasons for limiting each component are as described below.
Ｃ：０．０１％を超えると炭化物を形成し、金属間化合
物の析出量が減少して疲労強度を低下させるので、０．
０１％以下とする。C: If it exceeds 0.01%, carbides are formed and the amount of precipitated intermetallic compounds decreases, reducing fatigue strength.
01% or less.
Ｓｔ、Ｍｎ：いずれもＳｌｏｗ、Ｍｎ０１Ｍｎ５などの
介在物を形成し、疲労強度を低下させるので、０．０５
％以下とする。St, Mn: Both form inclusions such as Slow, Mn01Mn5, and reduce fatigue strength, so 0.05
% or less.
Ｐ、Ｓ：いずれも清浄度を悪くして靭性、延性を低下さ
せ、かつ疲労強度を低下させるので、Ｐについては０．
００８％以下、Ｓについては０．００４％以下とする。P, S: Since both impair cleanliness, reduce toughness and ductility, and reduce fatigue strength, P is 0.
0.008% or less, and S is 0.004% or less.
Ｎｉ：１５％未満では強度、靭性が低下し、１９％を超
えると１００％マルテンサイトが得られず強度低下を生
じるので、１５〜１９％とする。Ni: If it is less than 15%, the strength and toughness will decrease, and if it exceeds 19%, 100% martensite will not be obtained and the strength will decrease, so the Ni content is set at 15 to 19%.
Ｃｏ：８％未満では強度低下を生じ、１５％を超えると
靭性が低下するので、８〜１５％とする。Co: If it is less than 8%, the strength will decrease, and if it exceeds 15%, the toughness will decrease, so it is set at 8 to 15%.
Ｍｏ：３％未満では必要な強度が得られず、５．５％を
超えると靭性低下が著しいので、３．０〜５．５％とす
る。Mo: If it is less than 3%, the necessary strength cannot be obtained, and if it exceeds 5.5%, the toughness will be significantly lowered, so it is set to 3.0 to 5.5%.
Ｔｉ：０．４％未満では必要な強度が得られず、ｌ。Ti: If it is less than 0.4%, the necessary strength cannot be obtained, and l.
５％を超えるとＴｉｃ、ＴＩＮが増加して靭性が低下す
るので０．４〜１．５％とする。If it exceeds 5%, Tic and TIN will increase and the toughness will decrease, so the content is set at 0.4 to 1.5%.
Ａｌ：脱酸のために０．０５％以上が必要であるが、０
．１５％を超えるとＡ２□Ｏ，ｌ介在物が多（なって靭
性が低下するので、０．０５〜０．１５％とする。Al: 0.05% or more is required for deoxidation, but 0
．． If it exceeds 15%, there will be a large number of A2□O,l inclusions, resulting in a decrease in toughness, so the content is set at 0.05 to 0.15%.
Ｎ：疲労強度に悪影響を与える有害元素で、０．００５
％を超えるとＴｉＮが増加し、靭性を低下させるのに加
えて、これが点列状となって疲労強度を著しく低下させ
るので、０．００５％以下とする。N: A harmful element that adversely affects fatigue strength, 0.005
If it exceeds 0.005%, TiN will increase and in addition to lowering the toughness, it will also form a dot array and significantly lower the fatigue strength.
上記素材鋼は介在物量を低くするために、■ＯＤ等の脱
ガス処理をして製造してもよいが、好ましくは真空誘導
溶解を行って１を棒鋼片を得、これを高真空アークによ
る再溶解にて素材鋼塊とするのが望ましい。In order to reduce the amount of inclusions, the above steel material may be manufactured by degassing treatment such as It is desirable to make a raw steel ingot by remelting.
上記素材鋼塊は、通常は熱間鍛造あるいは熱間押出によ
って厚肉中空の継目無管に加工し、これを直接あるいは
例えば８３０°Ｃに１時間保持後空冷する固溶化処理し
て、内外面切削し、その後、冷間加工により主として肉
厚を滅じてベルト用素管とする。The above-mentioned raw steel ingot is usually processed into a thick-walled hollow seamless tube by hot forging or hot extrusion, which is then subjected to solution treatment either directly or by holding it at, for example, 830°C for 1 hour and then cooling in air, so that the inner and outer surfaces are It is cut and then cold-worked to mainly reduce the wall thickness to obtain a raw belt tube.
この場合、上記熱間加工は１０００〜１２００°Ｃの温
度域で行うのが望ましい、すなわち、１０００゛Ｃ未満
では変形抵抗が大きく、また１２００°Ｃを超えると延
性が低下し、表面欠陥のない継目無管を高能率に得難い
が、上記温度域であれば問題なく継目無管が得られる。In this case, it is desirable to carry out the above hot working in a temperature range of 1000 to 1200°C. In other words, below 1000°C, the deformation resistance is large, and above 1200°C, the ductility decreases and there is no surface defect. Although it is difficult to obtain seamless pipes with high efficiency, seamless pipes can be obtained without problems in the above temperature range.
また、冷間加工に先って固溶化処理を施す場合、その処
理は８００〜８５０°Ｃの温度域で施すのがよい、すな
わち、８００°Ｃ未満では未固溶析出物が残って靭性が
低下し、また８５０℃を趙えると結晶粒が粗大化して延
性が低下するからである。In addition, when performing solution treatment prior to cold working, it is best to perform the treatment at a temperature range of 800 to 850°C. This is because if the temperature is lowered and the temperature exceeds 850°C, the crystal grains will become coarser and the ductility will decrease.
さらに、冷間加工はスピニング加工とベルト圧延の２つ
の手段がよく知られており、通常はこれらを単独あるい
は組合せて実施するが、スピニング加工を施す場合の１
回当りの加工率（減肉率）は９０％以下で行うのが望ま
しい。Furthermore, two well-known methods of cold working are spinning and belt rolling, and these are usually carried out singly or in combination;
It is desirable that the processing rate (thickness reduction rate) per cycle be 90% or less.
すなわち、９０％を超えると延性が低下し、加工中に割
れが生じるからである。また、この冷間加工における最
終肉厚は０．３ｍｍ以上とするのが望ましい、すなわち
、０．３ｍ未満の肉厚に加工すると割れが発生し易くな
るからである。That is, if it exceeds 90%, ductility decreases and cracks occur during processing. Further, it is desirable that the final wall thickness in this cold working is 0.3 mm or more, because cracks are likely to occur if the wall thickness is less than 0.3 m.
なお、冷間加工を複数回繰り返して施す場合は、その加
工繰り返し間で上記した８００〜８５０°Ｃでの軟化の
ため固溶化処理を施す。In addition, when cold working is repeated multiple times, the solid solution treatment for softening at 800 to 850°C is performed between the repeated workings.
上記冷間加工によって０．３ｍｓ以上の肉厚に加工した
ベルト素管は、例えば８３０°Ｃに１時間保持して後空
冷する最終の固溶化処理を施して後、ベルトとして必要
な幅に適宜切断され、ベルト圧延機を用いて所定肉厚、
直径のベルトに加工するが、この時の加工率は５０％以
下で行うのがよい、すなわち、５０％を趙えると次工程
で施す時効処理後の延性が劣化するためである。また、
上記必要幅への切断時に切断パリを生じさせないことが
必要である。すなわち、切断パリが発生するとこれが疲
労破壊の起点となる恐れがあるからである。The belt raw tube processed into a wall thickness of 0.3 ms or more by the above-mentioned cold processing is subjected to a final solid solution treatment, for example, held at 830°C for 1 hour and then air cooled, and then adjusted to the width required as a belt. Cut to a specified thickness using a belt rolling machine.
The belt is processed into a belt with a certain diameter, but the processing rate at this time is preferably 50% or less, because if the processing rate is reduced by 50%, the ductility after the aging treatment performed in the next step will deteriorate. Also,
It is necessary to avoid cutting edges when cutting to the required width. That is, if a cut burr occurs, it may become a starting point for fatigue failure.
Ｏ時効処理
上記の加工によって得られたＨν３００程度のベルト硬
度をＨｖ５００〜５５０程度に高めるために時効処理を
施す、このための時効処理条件としては、４５０〜５２
０°Ｃの温度域に１〜ｌＯ時間保持するのが望ましい。O Aging Treatment Aging treatment is performed to increase the belt hardness of about Hv300 obtained by the above processing to about Hv500-550.The aging treatment conditions for this are 450-52
It is desirable to maintain the temperature in the 0°C temperature range for 1 to 10 hours.
すなわち、４５０°Ｃ未満、１時間未満の処理では硬度
上昇が図れず、使用中にベルトが伸びて破断してしまう
からであり、また、５２０°Ｃを超え、１０時間を鰯え
る処理では軟化してしまうからである。In other words, processing at temperatures below 450°C for less than 1 hour will not increase the hardness and the belt will stretch and break during use, while processing at temperatures above 520°C for 10 hours will soften the belt. This is because you end up doing it.
Ｏ表面硬化処理
表面硬化処理手段としては浸炭あるいは窒化いずれの手
段も採用しうるが、望ましくは窒化手段を採用するのが
よい、そして、窒化手段の処理条件としては、純アンモ
ニアガス中で４５０〜５３０°Ｃの温度域に２〜１０時
間保持するのが望ましい、すなわち、４５０°Ｃ未満、
２時間未満の処理ではベルトの表面硬度を後述するＨｖ
７８０以上とすることができないからであり、また５３
０℃超え、１０時間趙えの処理では後述するベルトの表
面硬度がＨｖ８６０を超えてしまうからである。O surface hardening treatment As the surface hardening treatment means, either carburizing or nitriding can be used, but it is preferable to use nitriding.The treatment conditions for the nitriding means are It is desirable to hold in the temperature range of 530 °C for 2 to 10 hours, i.e. below 450 °C,
When the treatment time is less than 2 hours, the surface hardness of the belt is Hv, which will be described later.
This is because it cannot be more than 780, and 53
This is because the surface hardness of the belt, which will be described later, will exceed Hv860 if the temperature exceeds 0° C. for 10 hours.
表面硬化処理後のベルトの表面硬度は、内外面とも７８
０〜８６０Ｈｖの範囲円に調整することが望まれる。７
８０Ｈｖ未満ではショットピーニング後に１２０ｋｇｆ
／閤１以上の圧縮残留応力が確保されない可能性があり
、８６０Ｈｖ超では表面が読比する危険性がある。なお
、この表面硬化なしでは、引き続きショットピーニング
を行っても高々１００ ｋｇ ｆ ／ｃｍ”の圧縮残留
応力しか得られない。The surface hardness of the belt after surface hardening treatment is 78 on both the inner and outer surfaces.
It is desirable to adjust the range circle from 0 to 860 Hv. 7
Below 80Hv, 120kgf after shot peening
There is a possibility that a compressive residual stress of 1/1 or more cannot be secured, and if it exceeds 860 Hv, there is a risk that the surface will become uneven. Note that without this surface hardening, even if shot peening is subsequently performed, a compressive residual stress of only 100 kg f /cm'' can be obtained at most.
Ｏショットピーニング
難破…性粒子の種類
液体に分散させるため、比重が小さく、しかも高硬度の
ベルト表面に衝突して、変形・破壊が容易には生じ難い
材料が望ましい。具体的にはアルミナ、ジルコニア等の
セラミックあるいはＪＩＳ０４４０４ ５ＫＳ４〜５Ｋ
Ｓ４４規定されるハイス等がこれに合致する。なかでも
アルミナは、経済性、比重の点でも最も好ましい、ガラ
スは容易に破壊され、吹き付は時のエネルギーをベルト
表面に与えることがなく、疵を付けるだけである。Types of O-shot peening breakable particles Since the particles are dispersed in a liquid, it is desirable to use a material that has a low specific gravity and is not easily deformed or broken when it collides with the highly hard belt surface. Specifically, ceramics such as alumina and zirconia or JIS04404 5KS4~5K
High speed steel etc. specified in S44 correspond to this. Among them, alumina is the most preferable in terms of economy and specific gravity.Glass is easily destroyed, and spraying does not apply time energy to the belt surface and only causes scratches.
難破損性粒子の径
５〜１０μｍを適当とする。５μｍ未満になると粒子の
もつエネルギーが小さく、ベルト表面に十分な塑性変形
を与えることが出来ない。その結果として、圧縮残留応
力は十分に増大せず、また表面の凹凸も小さく、潤滑油
を貯えることが出来ない、一方、１００μｍを超えると
ベルト表面に衝突する確率が低くなり、局所的に圧縮残
留応力の変化が生じるとともに、表面の凹凸が大きくな
り、疲労破壊の起点となる。ベルト表面の疵は、長さ２
０μｍを超えると疲労破壊の起点になり得る。衝突時の
変形面積を考えると５０μｍ以下が特に好ましい。The suitable diameter of the hard-to-break particles is 5 to 10 μm. When the particle size is less than 5 μm, the energy of the particles is small and it is not possible to impart sufficient plastic deformation to the belt surface. As a result, the compressive residual stress does not increase sufficiently, and the surface unevenness is small, making it impossible to store lubricating oil.On the other hand, if it exceeds 100 μm, the probability of collision with the belt surface is low, and local compression As the residual stress changes, the surface irregularities become larger, which becomes the starting point for fatigue failure. The flaw on the belt surface has a length of 2
If it exceeds 0 μm, it may become a starting point for fatigue failure. Considering the deformation area at the time of collision, the thickness is particularly preferably 50 μm or less.
液体の種類
難破損性粒子をショットする際の媒体である液体として
は、具体的には水、粘度が水の１〜２倍程度の鉱物油、
植物油、更にはアルコール、アセトン等を用いることが
できるが、工業的には水が最も好ましい。Types of liquids Examples of liquids used as a medium for shooting hard-to-break particles include water, mineral oil with a viscosity about 1 to 2 times that of water,
Although vegetable oil, alcohol, acetone, etc. can be used, industrially, water is most preferred.
難破損性粒子と液体の混合比
重量比で１／２〜ｌ／１０が望ましい、ｌ：２より濃い
場合、混合液の分散が十分でなくノズル内で詰まり易く
なる。１： １０より薄い場合は、吹き付時間を長くし
ても圧縮残留応力を大きくすることが出来ない。The mixing ratio of the hard-to-break particles and the liquid is preferably 1/2 to 1/10 by weight; if it is thicker than 1:2, the mixed liquid is not sufficiently dispersed and tends to clog in the nozzle. If it is thinner than 1:10, the compressive residual stress cannot be increased even if the spraying time is increased.
第２図は前述した１８％Ｎｉマルエージ鋼を素材とする
金属ベルトに時効処理、窒化処理を加えて硬度８３０Ｈ
ｖ、圧縮残留応力６５ｋｇｆ１０ｎ”に調整したベルト
表面に、球状アルミナと水の混合流体を吹き付けた時の
混合比と吹き付は後の圧縮残留応力との関係を示したグ
ラフである。球状アルミナの粒径は２０μｍ、混合流体
の吹き付は時間、吹き付は圧力（元圧）は夫々３０秒／
ｃｍ、３．５気圧で、いずれも一定である。混合流体
の吹き付けにより圧縮残留応力は上昇するが、なかでも
混合比が特に１／２〜ｌ／１０の間で圧縮残留応力がほ
ぼ一定で高い値を示している。Figure 2 shows a metal belt made from the aforementioned 18% Ni marage steel that has been subjected to aging treatment and nitriding treatment to reach a hardness of 830H.
This is a graph showing the relationship between the mixture ratio of spherical alumina and water and the subsequent compressive residual stress when a mixed fluid of spherical alumina and water is sprayed onto the belt surface adjusted to have a compressive residual stress of 65kgf10n''. The particle size is 20 μm, the time for spraying the mixed fluid, and the pressure (original pressure) for spraying are 30 seconds/30 seconds each.
cm and 3.5 atm, both of which are constant. Although the compressive residual stress increases due to the spraying of the mixed fluid, the compressive residual stress remains almost constant and exhibits a high value especially when the mixing ratio is between 1/2 and 1/10.
混合流体の吹き付は圧力
元圧で２．５〜１０気圧が望ましい。これが２．５気圧
未満になると、粒子に与えるエネルギーが小さ（なり、
残留応力は小さくなる。また混合液体をノズルから円滑
に吹き付けことが困難となる。The mixed fluid is preferably sprayed at a pressure source of 2.5 to 10 atm. When this becomes less than 2.5 atmospheres, the energy given to the particles becomes small (
Residual stress becomes smaller. Moreover, it becomes difficult to spray the mixed liquid smoothly from the nozzle.
１０気圧を超えると、粒子による塑性変形を通り越し、
表面を研磨するようになり、せっかく高い残留応力を付
与しても、その層を取り除いてしまう、しかもベルトは
基本的に１＜（０，２■以下）、不必要に振動させたり
、変形させてしまう。When the pressure exceeds 10 atm, plastic deformation due to particles is overcome,
The surface is polished, and even if a high residual stress is applied, that layer is removed, and the belt is basically 1 < (0, 2 ■ or less), causing unnecessary vibration or deformation. It ends up.
混合流体の吹き付は時間
１ａ＋＋当り吹き付は時間を１５秒未満にすると、圧縮
残留応力層は浅くなり、表面の圧縮残留応力も低下する
。これが６０秒を超えると圧縮残留応力付与効果が飽和
し、さらに続けると、圧縮残留応力層が深くはなるが逆
に圧縮残留応力は減少する。従って、１ｃｍ当り吹き付
は時間で表わして１５〜６０秒が望ましい。When the mixed fluid is sprayed for less than 15 seconds per time 1a++, the compressive residual stress layer becomes shallow and the compressive residual stress on the surface also decreases. If this exceeds 60 seconds, the compressive residual stress imparting effect becomes saturated, and if it continues further, the compressive residual stress layer becomes deeper, but the compressive residual stress decreases. Therefore, it is desirable to spray for 15 to 60 seconds per 1 cm.
第３図は、第２図を求めるにあたって使用したベルト表
面に、同一の混合流体（但し混合比ｌ：６で一定）を吹
き付けたときの、吹き付は圧力および時間の圧縮残留応
力に対する影響度を示したグラフである。吹き付は時間
が６０秒以下では吹き付は圧力が大きくなるほど、圧縮
残留応力が増大する。また、いずれの圧力の場合も吹き
付は時間が１５秒／ ｃｔａ以上で特に大きな応力増大
が見られる。Figure 3 shows the influence of pressure and time on compressive residual stress when the same mixed fluid (mixing ratio l:6 is constant) is sprayed onto the belt surface used to obtain Figure 2. This is a graph showing When the spraying time is 60 seconds or less, the compressive residual stress increases as the spraying pressure increases. In addition, for any pressure, a particularly large increase in stress is observed when the spraying time is 15 seconds/cta or more.
次に、本発明の実施結果を説明する。Next, the results of implementing the present invention will be explained.
前述した１８％Ｎ＋マルエージ鋼を素材とするベルト（
厚み０．１５〜０．２ｍ）に、第１表に示す条件１−Ｖ
で時効処理および窒化処理を施した。A belt made of the aforementioned 18% N + marage steel (
thickness 0.15 to 0.2 m), under the conditions 1-V shown in Table 1.
Aging treatment and nitriding treatment were performed.
窒化処理後のベルトの外表面および内表面に種々の条件
で球状難破損性粒子と水との混合流体を吹き付け、内外
面の圧縮残留応力付与を行った後、両県応力振幅７５
ｋｇ ｆ ７ｍ”での回転試験でベルトが破断するまで
の繰り返し回数を調査した。結果を第２表にＡ−Ｆに示
す、なお、Ｃには比較のために行ったガラスと空気の混
合流体の吹き付は結果も合せて示している。また、一部
については、１０枚のベルトを重ね合わせたものに同一
試験（１０枚の平均応力振幅を７５ｋｇｆ、／＋＋＊”
に調整）を施した結果も示している。ベルトを重ねた合
せた場合の破断とは、いずれかのベルトに最初に生じた
破断のことである。破断までの操り返し回数が５００万
回以上のものを本発明例、それ以外のものを比較例とし
て区分している。なお、これらの例は、前述した１８％
Ｎ！マルエージ鋼を対象としており、対象鋼が変われば
この区分も当然変化して来る０例えば、前述した１８％
Ｎｉマルエージ鋼においてＴｉ量を減少させれば、それ
だけでベルトの疲労強度・寿命が改善される。その結果
、Ｔｉ減少前に比較例に区分されていたものもＴＩ減少
後は本発明例に区分される事態も生じ得るのである。After nitriding, a mixed fluid of spherical breakable particles and water was sprayed on the outer and inner surfaces of the belt under various conditions to impart compressive residual stress to the inner and outer surfaces.
We investigated the number of repetitions until the belt breaks in a rotation test at 7 m".The results are shown in Table 2, A-F. C shows a mixed fluid of glass and air for comparison. The spraying results are also shown.In addition, for some parts, the same test was carried out on 10 overlapping belts (average stress amplitude of 10 belts was 75 kgf, /++*"
The results are also shown. A rupture in the case of stacked belts is a rupture that occurs first in one of the belts. Those that have been repeated 5,000,000 times or more before breaking are classified as examples of the present invention, and the others as comparative examples. Note that these examples are based on the 18% mentioned above.
N! It targets maraging steel, and if the target steel changes, this classification will naturally change.For example, the 18% mentioned above
Reducing the amount of Ti in Ni maraging steel can improve the fatigue strength and life of the belt. As a result, a situation may arise where what was classified as a comparative example before the Ti reduction is classified as an inventive example after the Ti reduction.
第 １
表
Ａは、窒化処理後の表面硬度（圧縮残留応力）を変化さ
せた例である。窒化処理後の表面硬度が７３０ Ｈｖの
場合は、操り返し回数が１７２万回であるが、７８０．
８５０Ｈｖの場合は４０００万回を超え、１０枚重ねて
も疲労強度は殆ど低下していない、９３０Ｈｖの場合は
表面に脆化層が形成され、１６万回で望性破壊を生じた
。Table 1 A shows examples in which the surface hardness (compressive residual stress) after nitriding treatment was changed. When the surface hardness after nitriding treatment is 730 Hv, the number of repetitions is 1.72 million times, but 780.
In the case of 850Hv, the fatigue strength was more than 40 million times, and the fatigue strength hardly decreased even after stacking 10 sheets.In the case of 930Hv, an embrittlement layer was formed on the surface, and desired failure occurred after 160,000 times.
Ｂは、最終圧縮残留応力をベルトの内外面で変化させた
例である。内面の圧縮残留応力が８０ｋｇｆ／ｍ”と低
い場合は、外面の圧縮残留応力が１６０ｋｇ（／ｌａｎ
”と高（でも疲労寿命が掻めて低い。B is an example in which the final compressive residual stress is varied on the inner and outer surfaces of the belt. When the compressive residual stress on the inner surface is as low as 80 kgf/m, the compressive residual stress on the outer surface is as low as 160 kg (/lan).
” and high (but the fatigue life is extremely low.
また、このベルトの破面を調査したところ、起点は内表
面直下にあり、内面より疲労破壊したことが判った。Further, when the fracture surface of this belt was investigated, it was found that the starting point was just below the inner surface, indicating that the fatigue fracture occurred from the inner surface.
Ｃは、球状粒子の材質、粒径を種々変更した例である。C is an example in which the material and particle size of the spherical particles were variously changed.
ガラスおよび粒径が１５０μｍのアルミナを除けば、い
ずれも繰り返し回数は１０００万回を超えている。Except for glass and alumina with a particle size of 150 μm, the number of repetitions exceeded 10 million times in all cases.
Ｄは、粒子と水との混合比（重量比）を変更した例であ
る。この比率が１ｚ４のものを除けば、繰り返し回数は
全て５００万回を超えている。D is an example in which the mixing ratio (weight ratio) of particles and water was changed. With the exception of the one with a ratio of 1z4, the number of repetitions is all over 5 million.
Ｅは、混合流体の吹き付は圧を変化させた例である。２
気圧の場合に繰り返し回数が２５万回である以外は、９
００万回を超え、７気圧の場合は３７００万回に及んで
いる。E is an example in which the pressure of the mixed fluid is varied. 2
9 except that in the case of atmospheric pressure, the number of repetitions is 250,000 times.
It exceeds 37 million times at 7 atmospheres.
Ｆは、混合流体の吹き付は時間を変化させた例である。F is an example in which the spraying time of the mixed fluid is varied.
吹き付は時間が５秒のものを除けば、いずれも２００万
回を超えている。All sprays were sprayed more than 2 million times, except for the one that lasted 5 seconds.
Ｇは、シｑｙトのみで時効処理、窒化処理を行わなかっ
た場合、シッットに代えてローラによる曲げ変形で圧縮
残留応力を付与した場合、シッットを行わずに表面硬化
のままで回転試験を実施した場合を示している。いずれ
も繰り返し回数は僅かで、疲労強度・寿命は著しく劣っ
た結果になっている。For G, when aging treatment and nitriding treatment were not performed with sit only, when compressive residual stress was applied by bending deformation with a roller instead of sitting, and when a rotation test was performed with the surface hardened without sitting. This shows the case where In both cases, the number of repetitions was small, and the results showed that the fatigue strength and life were significantly inferior.
本発明の製造方法は、従来技術では達し得ながった高レ
ベルの疲労強度・寿命を金属製ベルトに付与し得る。従
って、本発明の方法およびこれによって製造された本発
明ベルトは、自動車用無段変速機や高トルクが要求され
る各種産業機械等の動力伝達用ベルトに適用して、その
耐久性を著しく向上させるものである。The manufacturing method of the present invention can provide a metal belt with a high level of fatigue strength and life that could not be achieved using conventional techniques. Therefore, the method of the present invention and the belt of the present invention produced by the method can be applied to power transmission belts for continuously variable transmissions for automobiles and various industrial machines that require high torque, and their durability can be significantly improved. It is something that makes you
第１図は圧縮残留応力と疲労寿命との関係を従来法と本
発明法とについて示した図表、第２図は圧縮残留応力に
対する混合流体の混合比の影響度を示す図表、第３図は
同じく混合流体の吹き付は圧および吹き付は時間の影響
度を示すグラフである。
圧縮残留応力（に１／−）Figure 1 is a chart showing the relationship between compressive residual stress and fatigue life for the conventional method and the method of the present invention, Figure 2 is a chart showing the influence of the mixing ratio of mixed fluids on compressive residual stress, and Figure 3 is a chart showing the influence of the mixing ratio of mixed fluids on compressive residual stress. Similarly, the graph shows the influence of pressure and time on spraying of mixed fluid. Compressive residual stress (1/-)
Claims (1)
外表面に、難破損性粒子と液体との混合流体を吹き付け
ることを特徴とする動力伝達用金属ベルトの製造方法。 ２、請求項１に記載の製造方法によって製造された外表
面１５０ｋｇｆ／ｍｍ＾２以上、内表面１２０ｋｇｆ／
ｍｍ＾２以上の各圧縮残留応力を保有する動力伝達用金
属ベルト。[Claims] 1. A method for manufacturing a metal belt for power transmission, which comprises spraying a fluid mixture of unbreakable particles and liquid onto the inner and outer surfaces of a metal belt that has undergone surface hardening treatment after aging treatment. 2. Outer surface 150 kgf/mm^2 or more and inner surface 120 kgf/mm^2 manufactured by the manufacturing method according to claim 1.
A metal belt for power transmission that has compressive residual stress of mm^2 or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30826288A JPH02154834A (en) | 1988-12-06 | 1988-12-06 | Manufacture of metal belt for power transmission |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30826288A JPH02154834A (en) | 1988-12-06 | 1988-12-06 | Manufacture of metal belt for power transmission |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02154834A true JPH02154834A (en) | 1990-06-14 |
Family
ID=17978894
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30826288A Pending JPH02154834A (en) | 1988-12-06 | 1988-12-06 | Manufacture of metal belt for power transmission |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02154834A (en) |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3616716A1 (en) * | 1985-05-18 | 1986-11-20 | Honda Giken Kogyo K.K., Tokio/Tokyo | LAMINATED METAL TAPE FOR TORQUE TRANSMISSION DEVICES AND METHOD FOR THE PRODUCTION THEREOF |
| JPH09323133A (en) * | 1996-06-05 | 1997-12-16 | Hirata:Kk | Method for manufacturing multilayer belt made of metal |
| WO1999054639A1 (en) * | 1998-04-17 | 1999-10-28 | Honda Giken Kogyo Kabushiki Kaisha | Belt for continuously variable transmission |
| JP2000225567A (en) * | 1999-02-05 | 2000-08-15 | Toyota Motor Corp | Shot peening method for metal plate |
| US6309474B1 (en) | 1999-03-04 | 2001-10-30 | Honda Giken Kogyo Kabushiki Kaisha | Process for producing maraging steel |
| JP2002038251A (en) * | 2000-07-24 | 2002-02-06 | Dowa Mining Co Ltd | Method for manufacturing endless ring for metal belt of continuously variable transmission |
| FR2823766A1 (en) * | 2001-04-18 | 2002-10-25 | Imphy Ugine Precision | Ring made from maraging steel band for manufacture of a belt for a continuously variable transmission used in a motor vehicle is surface-hardened by pre-stressed shot blasting |
| JP2003145427A (en) * | 2001-11-19 | 2003-05-20 | Toyota Motor Corp | Endless metal belt manufacturing method |
| US6733600B2 (en) * | 2000-07-24 | 2004-05-11 | Nissan Motor Co., Ltd. | Nitrided maraging steel and method of manufacture thereof |
| US6858099B2 (en) | 2001-04-06 | 2005-02-22 | Honda Giken Kogyo Kabushiki Kaisha | Steel material production method |
| JP2005256870A (en) * | 2004-03-09 | 2005-09-22 | Toyota Motor Corp | Method for manufacturing endless metal belt |
| WO2007142312A1 (en) * | 2006-06-08 | 2007-12-13 | K. K. Endo Seisakusho | Tube for fixing and process for producing the same |
| JP2016503865A (en) * | 2012-12-27 | 2016-02-08 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツングＲｏｂｅｒｔ Ｂｏｓｃｈ Ｇｍｂｈ | Drive belt provided with a ring set of a steel ring with a nitride layer and method for determining the thickness of such a nitride layer |
| JP2016505092A (en) * | 2012-12-24 | 2016-02-18 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツングＲｏｂｅｒｔ Ｂｏｓｃｈ Ｇｍｂｈ | Heat treatment process in manufacturing method of ring set for drive belt |
-
1988
- 1988-12-06 JP JP30826288A patent/JPH02154834A/en active Pending
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3616716A1 (en) * | 1985-05-18 | 1986-11-20 | Honda Giken Kogyo K.K., Tokio/Tokyo | LAMINATED METAL TAPE FOR TORQUE TRANSMISSION DEVICES AND METHOD FOR THE PRODUCTION THEREOF |
| DE3616716C2 (en) * | 1985-05-18 | 1998-08-20 | Honda Motor Co Ltd | Laminated metallic tape for torque transmission devices and method for the production thereof |
| JPH09323133A (en) * | 1996-06-05 | 1997-12-16 | Hirata:Kk | Method for manufacturing multilayer belt made of metal |
| US6432012B1 (en) | 1998-04-17 | 2002-08-13 | Honda Giken Kogyo Kabushiki Kaisha | Belt for continuously variable transmission |
| WO1999054639A1 (en) * | 1998-04-17 | 1999-10-28 | Honda Giken Kogyo Kabushiki Kaisha | Belt for continuously variable transmission |
| JPH11303943A (en) * | 1998-04-17 | 1999-11-02 | Honda Motor Co Ltd | Belt for continuously variable transmission |
| JP2000225567A (en) * | 1999-02-05 | 2000-08-15 | Toyota Motor Corp | Shot peening method for metal plate |
| US6309474B1 (en) | 1999-03-04 | 2001-10-30 | Honda Giken Kogyo Kabushiki Kaisha | Process for producing maraging steel |
| JP2002038251A (en) * | 2000-07-24 | 2002-02-06 | Dowa Mining Co Ltd | Method for manufacturing endless ring for metal belt of continuously variable transmission |
| US6733600B2 (en) * | 2000-07-24 | 2004-05-11 | Nissan Motor Co., Ltd. | Nitrided maraging steel and method of manufacture thereof |
| US6858099B2 (en) | 2001-04-06 | 2005-02-22 | Honda Giken Kogyo Kabushiki Kaisha | Steel material production method |
| FR2823766A1 (en) * | 2001-04-18 | 2002-10-25 | Imphy Ugine Precision | Ring made from maraging steel band for manufacture of a belt for a continuously variable transmission used in a motor vehicle is surface-hardened by pre-stressed shot blasting |
| JP2003145427A (en) * | 2001-11-19 | 2003-05-20 | Toyota Motor Corp | Endless metal belt manufacturing method |
| JP2005256870A (en) * | 2004-03-09 | 2005-09-22 | Toyota Motor Corp | Method for manufacturing endless metal belt |
| WO2007142312A1 (en) * | 2006-06-08 | 2007-12-13 | K. K. Endo Seisakusho | Tube for fixing and process for producing the same |
| JP2016505092A (en) * | 2012-12-24 | 2016-02-18 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツングＲｏｂｅｒｔ Ｂｏｓｃｈ Ｇｍｂｈ | Heat treatment process in manufacturing method of ring set for drive belt |
| JP2016503865A (en) * | 2012-12-27 | 2016-02-08 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツングＲｏｂｅｒｔ Ｂｏｓｃｈ Ｇｍｂｈ | Drive belt provided with a ring set of a steel ring with a nitride layer and method for determining the thickness of such a nitride layer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101626848B (en) | Seamless steel pipe, hollow spring utilizing seamless steel pipe, and process for manufacturing the same | |
| JP5251868B2 (en) | Carbonitriding induction-hardened steel parts with excellent surface pressure fatigue strength at high temperatures and methods for producing the same | |
| JPH02154834A (en) | Manufacture of metal belt for power transmission | |
| WO2000049186A1 (en) | Spring of excellent fatigue resisting characteristics and surface treatment method for manufacturing the same | |
| JP5207805B2 (en) | Steel parts with excellent bending fatigue strength and manufacturing method thereof | |
| JP3562192B2 (en) | Component for induction hardening and method of manufacturing the same | |
| JP2009030134A (en) | Semifinished product for nitrided gear, and nitrided gear | |
| JP2007131907A (en) | Steel for induction hardening with excellent cold workability, and its manufacturing method | |
| JP2001073072A (en) | Carbo-nitrided parts excellent in pitching resistance | |
| JPH0421757A (en) | High surface pressure gear | |
| JPH10251804A (en) | High strength spring steel | |
| WO2004065646A1 (en) | Steel product for induction hardening, induction-hardened member using the same, and methods for producing them | |
| JPH11131176A (en) | Induction hardened parts and production thereof | |
| JPH06172961A (en) | Parts for machine structure excellent in fatigue resistance, particularly in face fatigue strength and its production | |
| JPH1171654A (en) | Carburized gear | |
| JPH04311529A (en) | Continuous heat treating method for oil tempered steel wire for spring having high strength and high toughness | |
| JPS5916949A (en) | Soft-nitriding steel | |
| US6858099B2 (en) | Steel material production method | |
| JP2003003241A (en) | High strength spring steel wire | |
| JP2002121645A (en) | Steel for gear having excellent dedendum bending fatigue characteristic and facial pressure fatigue characteristic and gear | |
| JP3847350B2 (en) | Spring with excellent fatigue resistance and surface treatment method for producing the spring | |
| JP4006857B2 (en) | Cold forging steel for induction hardening, machine structural parts and manufacturing method thereof | |
| JP4976985B2 (en) | Manufacturing method of wire rod and steel bar with excellent low-temperature torsional characteristics | |
| JP4976986B2 (en) | Manufacturing method of steel wire with excellent low-temperature torsional characteristics | |
| JPH11131135A (en) | Induction-hardened parts and production thereof |