JPS6023618A - Cast iron crankshaft with high strength - Google Patents
Cast iron crankshaft with high strengthInfo
- Publication number
- JPS6023618A JPS6023618A JP58128476A JP12847683A JPS6023618A JP S6023618 A JPS6023618 A JP S6023618A JP 58128476 A JP58128476 A JP 58128476A JP 12847683 A JP12847683 A JP 12847683A JP S6023618 A JPS6023618 A JP S6023618A
- Authority
- JP
- Japan
- Prior art keywords
- pin
- hardened
- coil
- crankshaft
- cast iron
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229910001018 Cast iron Inorganic materials 0.000 title claims description 9
- 229910000734 martensite Inorganic materials 0.000 claims abstract description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 22
- 230000006698 induction Effects 0.000 claims description 14
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 12
- 229910052742 iron Inorganic materials 0.000 claims description 11
- 229910002804 graphite Inorganic materials 0.000 claims description 8
- 239000010439 graphite Substances 0.000 claims description 8
- 239000002344 surface layer Substances 0.000 claims description 8
- 229910001141 Ductile iron Inorganic materials 0.000 claims description 7
- 229910001566 austenite Inorganic materials 0.000 claims description 7
- 238000001816 cooling Methods 0.000 claims description 7
- 229910000831 Steel Inorganic materials 0.000 claims description 5
- 239000010410 layer Substances 0.000 claims description 5
- 239000010959 steel Substances 0.000 claims description 5
- 230000005496 eutectics Effects 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 230000000717 retained effect Effects 0.000 claims description 2
- 238000001556 precipitation Methods 0.000 claims 1
- 239000007788 liquid Substances 0.000 abstract description 2
- 238000010791 quenching Methods 0.000 description 8
- 230000000171 quenching effect Effects 0.000 description 7
- 229910000859 α-Fe Inorganic materials 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 4
- 239000000498 cooling water Substances 0.000 description 4
- 229910000976 Electrical steel Inorganic materials 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 238000005299 abrasion Methods 0.000 description 1
- 229910001563 bainite Inorganic materials 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C3/00—Shafts; Axles; Cranks; Eccentrics
- F16C3/04—Crankshafts, eccentric-shafts; Cranks, eccentrics
- F16C3/06—Crankshafts
- F16C3/08—Crankshafts made in one piece
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Ocean & Marine Engineering (AREA)
- Mechanical Engineering (AREA)
- Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、高強度鋳鉄製クランクシャフトに関し、詳し
くは、球状黒鉛鋳鉄製クランクシャフトを高周波焼入処
理によって、強度・＠Ｉ摩耗性の向上を図った高強度鋳
鉄製クランクシャフトにかかる。Detailed Description of the Invention The present invention relates to a crankshaft made of high-strength cast iron, and more specifically, a crankshaft made of spheroidal graphite cast iron that is made of high-strength cast iron with improved strength and @I wear resistance by induction hardening treatment. hangs on the crankshaft.
球状黒鉛鋳鉄を高周波焼入する場合、ｖｔ鉄鉄地地中炭
素濃度の変動が大きく、また、球状黒鉛の周囲は、ブル
ースアイと呼ばれる大きなフェライト部が存在するため
、高周波焼入してもフェライトが焼入硬化層に残存した
り、あるいは、このフェライトをもオーステナイト化す
るために、高周波焼入温度を上げると、焼入硬化層に残
留オーステナイトが残留して、高周波焼入の優れた特性
である焼入硬化層の圧縮残留応力が、安定して１ｑられ
ないという欠点がある。When spheroidal graphite cast iron is induction hardened, the underground carbon concentration of the VT iron varies greatly, and there is a large ferrite area called a blue eye around the spheroidal graphite, so ferrite is not produced even after induction hardening. If the induction hardening temperature is increased to change the ferrite to austenite, residual austenite will remain in the hardened layer and the excellent properties of induction hardening will be lost. There is a drawback that the compressive residual stress of a certain quench-hardened layer cannot be stably reduced to 1q.
このため、鋳鉄製クランクシャフトの強度、および、耐
摩耗性の向上には、クランクシャフトをオーステナイト
化温度域から、所定温度の塩浴に浸漬して恒温変態させ
る、いわゆる、ヘイナイ１〜処理が行われることがある
。Therefore, in order to improve the strength and wear resistance of cast iron crankshafts, the so-called Heinai 1 treatment, in which the crankshaft is immersed in a salt bath at a predetermined temperature to undergo isothermal transformation from the austenitizing temperature range, is carried out. It may happen.
しかし、このベイナイト処理では、クランクシャフト全
体の硬さが上昇すること、残留オーステナイトが残留し
やすいことから加工硬化性が強く、著しく機械加工性を
悪化する欠点がある。However, this bainite treatment has the disadvantage that the hardness of the entire crankshaft increases and that residual austenite tends to remain, resulting in strong work hardening and significantly deteriorating machinability.
本発明は、球状黒鉛鋳鉄の基地中の炭素濃度の変動や球
状黒鉛の周囲のブルースアイと呼ばれるフェライｌ一部
をも、十分オーステナイ１〜化さセるため、遊離黒鉛は
鉄に固溶するが、鉄と酸素との共晶点以下となる温度に
高周波加熱し、過共析鋼でも残留オーステナイトを析出
しない温度まで放冷後、急冷とする高周波焼入により、
球状黒鉛鋳鉄製クランクシャフトのピン平行部外周、お
よび、ピンの力・ランタウエイト側では、ピンとカウン
タウェイトの接続曲面部まで延在せしめた表面硬化層を
、マルテンサイトとトルースタイトの組織となし、圧縮
残留応力をもった表面硬化層とし、強度および耐摩耗性
を向」ニしたことを特徴とする高強度鋳鉄製クランクシ
ャフトを提供することを目的としている。The present invention sufficiently changes the carbon concentration in the matrix of spheroidal graphite cast iron and the part of the ferrite called blue eye around the spheroidal graphite into austenite. Therefore, free graphite is dissolved in iron. However, by induction quenching, which involves induction heating to a temperature below the eutectic point of iron and oxygen, cooling to a temperature at which residual austenite does not precipitate even in hypereutectoid steel, and then rapid cooling,
On the outer periphery of the parallel part of the pin of the spheroidal graphite cast iron crankshaft, and on the force/runtau weight side of the pin, a hardened surface layer extends to the connecting curved surface of the pin and counterweight, with a structure of martensite and troostite. The object of the present invention is to provide a high-strength cast iron crankshaft characterized by having a hardened surface layer with compressive residual stress and improved strength and wear resistance.
このような目的は、本発明によれば、球状黒鉛ｔＩ鉄製
クランクシャフトの、ビン平行部外周、および、ピンの
カウンタウェイト側では、ピンとカウンタウェイトの接
続曲面部まで、表面硬化層を延在−ｕしめた高強度鋳鉄
製クランクシャフトであって、
前記表面硬化層を、遊離黒鉛は鉄に固溶するが、鉄と酸
素との共晶点以下となる温度に高周波崩御すシし、過共
析鋼でも残留オーステナ−（１−を析出しない温度なで
防冷後、急冷する高周波焼入により、マルテンサイトと
トルースタイト
圧縮残留応力をもった表面硬化層としたことを特徴とす
る高強度鋳鉄製クランクシャフトにょって達成される。According to the present invention, a hardened surface layer is provided on the outer periphery of the parallel portion of the spherical graphite tI iron crankshaft and on the counterweight side of the pin to the connecting curved surface between the pin and the counterweight. A crankshaft made of high-strength cast iron with a high tensile strength, wherein the surface hardening layer is formed by high frequency disintegration at a temperature below the eutectic point of iron and oxygen, although free graphite is solidly dissolved in the iron. A high-strength cast iron characterized by having a hardened surface layer with martensite and troostite compressive residual stress by induction hardening, which involves rapid cooling after cooling at a temperature at which residual austainer (1-) does not precipitate even in analytical steel. This is achieved by using a manufactured crankshaft.
以下、添伺図面に基づいて、本発明の詳細な説明する。Hereinafter, the present invention will be described in detail based on the accompanying drawings.
クランクシャフトのピンｌ （φ４ ８ ｍｍＸ ２
６ ｍｍ）を、半円環状のカウンタウェイト側焼入′：
１イル５と、ピン１を包囲し°ζこれと対向するように
配置された、半円環状の外側焼入コイル９によって、ピ
ンに接触しないように包囲する。Crankshaft pin l (φ4 8 mm x 2
6 mm), semicircular counterweight side quenching':
The pin 1 is surrounded by a semicircular outer hardening coil 9 which surrounds the pin 1 and faces the pin 1 so as not to come into contact with the pin.
この時、半円環状のカウンタウェイト側焼入コイル５と
、半円環状の外側焼入コイル９は、それぞれに有してい
る２個の接点において接触されている。At this time, the semicircular counterweight-side hardened coil 5 and the semicircular outer hardened coil 9 are in contact with each other at their two contact points.
そして、半円環状の外側焼入コイル９に設げられた、図
示されないリード部に、８ＫＩＩＺ、８ （１ （１０
Ａ、４５Ｖの高周波電流を５秒間流すことによって、
前記外側焼入コイル９とカウンタウェイト側焼入二ｌイ
ルにより、ピン１のカウンタウェイト側２、および、ピ
ン１の外側４を含むピンｌの平行部外周ならびにピン１
とカウンタウェイトの接続曲面部３を加！；１シした後
、７秒間放冷して、カウンタウェイト側焼入コイル５の
冷Ｊ、１１水噴躬孔６、および、外側焼入コイル９の冷
却水噴射孔１ （ｌから、６０ｊ２／ｍｉｎの水用の焼
入液を、１５秒間噴射して第１図に示すように焼入硬化
層を形成させるものである。Then, 8KIIZ, 8 (1 (10
A. By passing a high frequency current of 45V for 5 seconds,
The outer quenching coil 9 and the counterweight side quenching coil reduce the outer periphery of the parallel portion of the pin 1 including the counterweight side 2 of the pin 1 and the outer side 4 of the pin 1, as well as the pin 1.
Add the connecting curved surface part 3 of the counterweight! After cooling for 7 seconds, the cooling water injection holes 6 of the counterweight side quenching coil 5 and the cooling water injection hole 1 of the outer quenching coil 9 (from l to 60j2/ A quenching liquid for water of 100 min was sprayed for 15 seconds to form a quenched hardened layer as shown in FIG.
このような、凸周波焼入過程におし」る、ピンｌのカウ
ンタウェイト側２、ピン１の外側４、および、ピンｌと
カウンタウェイトの接続曲面部３の部位の時間による温
度変化を第３図に示す。Temperature changes over time at the counterweight side 2 of the pin l, the outer side 4 of the pin 1, and the connecting curved surface portion 3 between the pin l and the counterweight during such a convex frequency hardening process are described below. Shown in Figure 3.
なお、」１記高周波焼入において、半円環状カランクラ
エイト側焼入コイル５には、ピン１とカウンタウェイト
の接続曲面部３を加熱するために、第２図に示すように
、突起部８と珪素鋼板７を配設しである。In addition, in the induction hardening described in item 1, the semicircular ring-shaped hardening coil 5 has a protrusion as shown in FIG. 8 and a silicon steel plate 7 are arranged.
一方、半円環状外側焼入二１イル９Ｇ、１、ピン■の外
側焼入部４の焼入体積を小さくするために、珪素鋼板１
１とフェライトコア１２を配設して、し１示されないリ
ードから供給されノコ１０１周波電流が、外側焼入コイ
ル内周部１３に流れにくくするように配慮しである。On the other hand, in order to reduce the hardened volume of the outside hardened part 4 of the semicircular outer hardened part 9G, 1, the silicon steel plate 1
1 and a ferrite core 12 are arranged to make it difficult for the saw 101 frequency current supplied from the leads (not shown) to flow into the inner circumferential portion 13 of the outer hardened coil.
以上により明らかなよ・うに、本発明にががるｉ！’！
＋強度紡鉄製クランクりャフトにＪ，れぽ、球状黒鉛鋳
鉄の基地中の炭素濃度の変動や球状黒鉛の周囲のブルー
スアイと呼ばれる７１５４１〜部をも、十分オーステナ
ー（ １−化さ・Ｕるため、遊！’１１１黒鉛は鉄に固
溶するが、鉄と炭素との共晶点以下となる温度に加熱し
、過共析鋼でも残留オーステナイトを析出しない温度ま
で放冷後、急冷とする高周波焼入により、球状黒鉛鋳鉄
製クランクシャフトのピン平行部外周、および、ピンの
カウンタウェイト側では、ピンとカウンタウェイトの接
続曲面部まで延在〜ｕしめた表面硬化層を、マルテンサ
イトとトルースタイトの組繊となし、圧縮残留応力をも
った表面硬化層とし、強度および耐摩耗性を向上できる
利点がある。As is clear from the above, the present invention is advantageous to i! '!
+ For crankshafts made of strong spun iron, changes in carbon concentration in the base of spheroidal graphite cast iron and the part 71541~ called blue eye around spheroidal graphite can be sufficiently austained (1-ized). Therefore, Yu!'111 graphite dissolves in iron, but it is heated to a temperature below the eutectic point of iron and carbon, allowed to cool to a temperature that does not precipitate retained austenite even in hypereutectoid steel, and then rapidly cooled. By induction hardening, a hardened surface layer is formed on the outer periphery of the parallel pin part of the spheroidal graphite cast iron crankshaft and on the counterweight side of the pin, extending to the connecting curved part of the pin and counterweight. It has the advantage of being a hardened surface layer with compressive residual stress, improving strength and abrasion resistance.
ちなみに、本発明にかかる高強度鋳鉄製クランクシャフ
トは、従来の高周波焼入しないクランクシャフトに比べ
、ねじり疲労強度が３０〜５０％、曲げ疲労強度が３０
〜５０％向上し、ピンの摩耗ｐが１１５〜１／ＩＯに低
減するばかりでなく、ビンｒＩＩＴ摩後に、ピンの打痕
つきの危険性が少ない。Incidentally, the high-strength cast iron crankshaft according to the present invention has a torsional fatigue strength of 30 to 50% and a bending fatigue strength of 30% compared to conventional crankshafts that are not induction hardened.
Not only is the pin wear p reduced by 115 to 1/IO, but there is also less risk of pin dents after IIT wear.
第１図は本発明にかかるクランクシャフトの断面図、第
２図は本発明にかかるクランクシャフトの高周波焼入状
態を示す主要ＩＪｉ面図、第３図は高周波焼入時におり
る、第２図の部位２、部位３、部位４の熱履歴を示す図
である。
１−−−−ピン
２ −−−ピンのカウンタウェイ１−側３− ピンとカ
ウンタウェイトの接続曲面４−・−ピンの外側
５−−−−−カウンタウェイト側焼入コイル６−−−一
−−冷却水噴射孔
７−−−−−一珪素鋼板
８−−−−−一突起（４１１
９−−−−−−外側焼入コイル
１０−−−−−・冷却水孔
１ｉ−−−−一珪素鋼板
１２−−−−・フェライトコア
１３−−−−−−外側焼入コイル内周部Ａ −−一焼入
硬化部Fig. 1 is a sectional view of the crankshaft according to the present invention, Fig. 2 is a main IJi plane view showing the state of induction hardening of the crankshaft according to the invention, and Fig. 3 is a cross-sectional view of the crankshaft according to the invention during induction hardening. It is a figure showing the thermal history of part 2, part 3, and part 4 of. 1---Pin 2---Counterway 1 side of pin 3- Connection curved surface between pin and counterweight 4---Outside of pin 5---Counterweight side hardened coil 6---1- - Cooling water injection hole 7 ------- Monosilicon steel plate 8 ------- One protrusion (411 9 ------- Outer hardened coil 10 ------- Cooling water hole 1i ---- Single-silicon steel plate 12 --- Ferrite core 13 ---Outer quenched coil inner peripheral part A ---First quench hardened part
Claims (1)
用、および、ピンのカウンタウェイト側では、ピンとカ
ウンタウェイトの接続曲面部まで、表面硬化層を延在せ
しめた高強度紡ｖ：、製クランクシャフトであって、 前記表面硬化層を、遊離黒鉛は鉄に固溶するが、鉄と酸
素との共晶点以下となる温度に高周波加熱し、過共析鋼
でも残留オーステナイトを析出しない温度なで防冷後、
急冷する高周波焼入により、マルテンサイトとトルース
タイトの組織となして、圧縮残留応力をもった表面硬化
層としたことを特徴とする高強度鋳鉄製クランクシャフ
ト。[Claims] A crankshaft made of 16-ball spheroidal graphite cast iron, a high-strength spun v with a hardened surface layer extending to the connecting curved surface of the pin and the counterweight on the pin parallel part for external use and on the counterweight side of the pin. :, the surface hardened layer is heated with high frequency to a temperature that is below the eutectic point of iron and oxygen, although free graphite is dissolved in iron, and retained austenite is formed even in hypereutectoid steel. After cooling at a temperature that will not cause precipitation,
A high-strength cast iron crankshaft characterized by rapid cooling and induction hardening to form a martensite and troostite structure into a hardened surface layer with compressive residual stress.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58128476A JPS6023618A (en) | 1983-07-14 | 1983-07-14 | Cast iron crankshaft with high strength |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58128476A JPS6023618A (en) | 1983-07-14 | 1983-07-14 | Cast iron crankshaft with high strength |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6023618A true JPS6023618A (en) | 1985-02-06 |
| JPH057447B2 JPH057447B2 (en) | 1993-01-28 |
Family
ID=14985675
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58128476A Granted JPS6023618A (en) | 1983-07-14 | 1983-07-14 | Cast iron crankshaft with high strength |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6023618A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63201206U (en) * | 1987-06-17 | 1988-12-26 | ||
| JPH03202418A (en) * | 1989-12-28 | 1991-09-04 | Nissan Motor Co Ltd | Heat treatment of cast-iron casting parts |
| JPH0429650U (en) * | 1990-06-29 | 1992-03-10 | ||
| JPH04191327A (en) * | 1990-11-27 | 1992-07-09 | Toyota Motor Corp | Manufacture of cast crank shaft |
| JPH07268480A (en) * | 1994-02-04 | 1995-10-17 | Mitsubishi Motors Corp | Cast iron crankshaft |
| JP2012247029A (en) * | 2011-05-30 | 2012-12-13 | Toyota Motor Corp | Crankshaft, and method of modifying surface thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5174918A (en) * | 1974-11-22 | 1976-06-29 | Motoren Turbinen Union |
-
1983
- 1983-07-14 JP JP58128476A patent/JPS6023618A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5174918A (en) * | 1974-11-22 | 1976-06-29 | Motoren Turbinen Union |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63201206U (en) * | 1987-06-17 | 1988-12-26 | ||
| JPH03202418A (en) * | 1989-12-28 | 1991-09-04 | Nissan Motor Co Ltd | Heat treatment of cast-iron casting parts |
| JPH0429650U (en) * | 1990-06-29 | 1992-03-10 | ||
| JPH04191327A (en) * | 1990-11-27 | 1992-07-09 | Toyota Motor Corp | Manufacture of cast crank shaft |
| JPH07268480A (en) * | 1994-02-04 | 1995-10-17 | Mitsubishi Motors Corp | Cast iron crankshaft |
| JP2012247029A (en) * | 2011-05-30 | 2012-12-13 | Toyota Motor Corp | Crankshaft, and method of modifying surface thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH057447B2 (en) | 1993-01-28 |
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