JPH02209413A - Manufacture of spheroidal graphite case iron gear raw material - Google Patents
Manufacture of spheroidal graphite case iron gear raw materialInfo
- Publication number
- JPH02209413A JPH02209413A JP3016889A JP3016889A JPH02209413A JP H02209413 A JPH02209413 A JP H02209413A JP 3016889 A JP3016889 A JP 3016889A JP 3016889 A JP3016889 A JP 3016889A JP H02209413 A JPH02209413 A JP H02209413A
- Authority
- JP
- Japan
- Prior art keywords
- annular cavity
- gear
- molten metal
- spheroidal graphite
- gates
- 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
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 14
- 229910002804 graphite Inorganic materials 0.000 title claims abstract description 14
- 239000010439 graphite Substances 0.000 title claims abstract description 14
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 9
- 239000002994 raw material Substances 0.000 title abstract 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title 2
- 229910052742 iron Inorganic materials 0.000 title 1
- 239000002184 metal Substances 0.000 claims abstract description 16
- 229910052751 metal Inorganic materials 0.000 claims abstract description 16
- 229910001141 Ductile iron Inorganic materials 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 claims description 31
- 239000002245 particle Substances 0.000 claims description 8
- 238000000034 method Methods 0.000 abstract description 16
- 230000002093 peripheral effect Effects 0.000 abstract 1
- 238000007796 conventional method Methods 0.000 description 8
- 229910001018 Cast iron Inorganic materials 0.000 description 7
- 238000010586 diagram Methods 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 238000001000 micrograph Methods 0.000 description 3
- 229910001563 bainite Inorganic materials 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000009661 fatigue test Methods 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、鋳鉄歯車素材、特に自動車用等に適した高強
度の鋳鉄歯車素材の製造法に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing cast iron gear materials, particularly high strength cast iron gear materials suitable for automobiles and the like.
動力伝達部品としての歯車は、近年は軽量かつ高強度で
しかも耐摩耗性、高精度を有することが要求されている
。In recent years, gears used as power transmission components are required to be lightweight, have high strength, wear resistance, and high precision.
一般に歯車素材は合金鋼が広く用いられているが、最近
特に軽量でかつ設計の自由度が大きい鋳鉄系の歯車も使
用されてきており、なかでも高強度を必要とする歯車に
ついては、オーステンバ処理を施した歯車を使う試みが
なされている。In general, alloy steel is widely used as the material for gears, but recently cast iron gears, which are particularly lightweight and offer greater freedom in design, have also come into use.For gears that require high strength, austenburized Attempts have been made to use gears with
そして、このような鋳鉄系の歯車は、従来、第２図に示
すような方法で一般に製造されている。Conventionally, such cast iron gears have been generally manufactured by a method as shown in FIG.
即ち、環状キャビティ１の外側へ設けた湯口２より溶湯
を注入し湯道３、堰５を通じて、鋳鉄歯車１を得るもの
である。しかし、上記従来方法においては、湯道付近、
例えば第２図におけるＣ部組織とその反対側、例えばＤ
部の組織が冷却速度の違いにより、０部の方がＤ部より
黒鉛粒径が大きく、また形状が悪くなり部分によって組
織が異なり均一ではない。That is, a cast iron gear 1 is obtained by injecting molten metal from a sprue 2 provided on the outside of an annular cavity 1 and passing through a runner 3 and a weir 5. However, in the above conventional method, near the runner,
For example, the C part structure in Fig. 2 and the opposite side, for example, D
Due to the difference in the cooling rate, the graphite grain size in part 0 is larger than that in part D, and the shape is worse, and the structure differs depending on the part and is not uniform.
このような不均一な組織をなくす対策方法として、第３
図に示すように、環状キャビティ１の内面に放射状に堰
３を設け、中央の湯口２より溶湯を注入するとともに環
状キャビティｌの外周の湯道３より堰８を介して溶湯を
注入する方法が開示されている（■アグネ、１９７６年
３月刊の［鋳鉄の鋳造方案図解集」の１３４頁に記載）
。As a countermeasure to eliminate such uneven structure, the third method is
As shown in the figure, there is a method in which weirs 3 are provided radially on the inner surface of an annular cavity 1, and molten metal is injected from a sprue 2 in the center and molten metal is injected from a runner 3 on the outer periphery of the annular cavity 1 via a weir 8. Disclosed (■ Agne, published on page 134 of [Illustrated collection of cast iron casting methods] published in March 1976)
.
しかしながら」１記対策方法においても、環状キャビテ
ィ１の内面に放射状に設けた堰３より環状キャビティ１
内に注入した溶湯と、環状キャビティ１の外周の湯道３
より堰８を介して環状キャビティｌ内に注入した溶湯が
合流する時間が、環状キャビティ１の外周の各部分によ
って大きく異なり、従って注入された後の冷却速度が環
状キャビティ外周の各部分によって異なる。そのため、
上記対策方法により製造された歯車素材によっても、特
に歯車の外周部の組織を均一にすることは困難であり、
本来持っている材質の強度と均一性を得ることができず
、高強度歯車素材への鋳物の適用は難しく、かつ設計者
および使用者の鋳鉄系歯車に対する信軌を損なう恐れが
ある。However, even in the countermeasure method described in item 1, the annular cavity 1 is
The molten metal injected into the interior and the runner 3 on the outer periphery of the annular cavity 1
The time for the molten metal injected into the annular cavity 1 through the weir 8 to join together differs greatly depending on each part of the outer periphery of the annular cavity 1, and therefore the cooling rate after injection differs depending on each part of the outer periphery of the annular cavity. Therefore,
Even with the gear material manufactured by the above-mentioned method, it is difficult to make the structure of the outer periphery of the gear uniform.
Since the inherent strength and uniformity of the material cannot be obtained, it is difficult to apply castings to high-strength gear materials, and designers and users may lose faith in cast iron gears.
歯車の歯部は他の部分に比べ歯車の性能レベルを決める
力がかかり、しかも歯部の強度は最も強度の弱い部分に
よって決定されるため、材質にバラツキがあることは好
ましくなく、歯部のどの部分においても均一な組織であ
ることが最も好ましい。The teeth of a gear are subjected to a force that determines the performance level of the gear compared to other parts, and the strength of the teeth is determined by the weakest part, so it is undesirable for there to be variations in the material, It is most preferable that the structure be uniform in all parts.
本発明の目的は、均一な組織で各歯部における強度のバ
ラツキがなくて、しかも高強度で信頬性の高い球状黒鉛
鋳鉄歯車素材の製造法を提供することである。An object of the present invention is to provide a method for manufacturing a spheroidal graphite cast iron gear material that has a uniform structure, has no variation in strength at each tooth portion, and has high strength and reliability.
上記目的を達成するために、本発明においては、鋳型内
の環状キャビティ中央に縦湯道を設け、環状キャビティ
下面に設けた堰より押しトげ法により、かつ同時に、縦
湯道から環状キャビティ内面へ放射状に設けた堰より溶
湯を注入し、全１溝たけの少なくても１．３倍以上の厚
さの部分における歯部において、球状化率８５％以上、
黒鉛粒径が７０μｍ以下であり、球状黒鉛の粒径が均一
に分布する球状黒鉛鋳鉄歯車素材を得ることを特徴とす
るものである。In order to achieve the above object, in the present invention, a vertical runner is provided in the center of an annular cavity in a mold, and a push-toe method is used from a weir provided on the lower surface of the annular cavity, and at the same time, from the vertical runner, the inner surface of the annular cavity is The molten metal is injected from the weir provided radially into the groove, and the spheroidization rate is 85% or more in the tooth part at least 1.3 times the thickness of one groove.
The present invention is characterized by obtaining a spheroidal graphite cast iron gear material in which the graphite particle size is 70 μm or less and the spheroidal graphite particle size is uniformly distributed.
本発明において黒鉛の球状化率はカンチメットにより測
定されたものであり、８５％以上であれば高強度歯車素
材として実用可能な程度の強度が得られる。より高強度
の歯車素材を得るためには、９５％以上とするのが好ま
しい。また、黒鉛粒径は強度向上のため７０μｍ以下と
する。７０μｍを越えることは、球状化率の低下および
組織の粗大化につながり、強度低下の原因となる。好ま
しくは２０〜５０μｍの粒径の黒鉛を均一に分散するの
が良い。In the present invention, the spheroidization rate of graphite is measured by Cantimet, and if it is 85% or more, a strength that is practical as a high-strength gear material can be obtained. In order to obtain a gear material with higher strength, it is preferably 95% or more. Further, the graphite particle size is set to 70 μm or less to improve strength. Exceeding 70 μm leads to a decrease in the spheroidization rate and coarsening of the structure, which causes a decrease in strength. Preferably, graphite having a particle size of 20 to 50 μm is uniformly dispersed.
環状キャビティ内面に放射状に設けた複数の堰を設ける
ことにより、注入された溶湯の渦流れが良好となり、歯
車素材全面において均一な組織のものが得られる。By providing a plurality of radially arranged weirs on the inner surface of the annular cavity, the vortex flow of the injected molten metal becomes good, and a uniform structure can be obtained over the entire surface of the gear material.
以下、本発明を図面を参照して更に詳述する。Hereinafter, the present invention will be explained in further detail with reference to the drawings.
第１図は本発明に係る製造法を説明するための概略構成
図である。図において、環状キャビティ１の中央に縦湯
道２を設け、これより注入された溶湯が環状キャビテイ
１内周部に放射状に設けた複数の堰６と環状キャビテイ
１下面に設けた複数の堰７により環状キャビティ１内へ
注入する。FIG. 1 is a schematic configuration diagram for explaining the manufacturing method according to the present invention. In the figure, a vertical runner 2 is provided in the center of the annular cavity 1, and the molten metal injected through the channel is passed through a plurality of weirs 6 provided radially around the inner circumference of the annular cavity 1 and a plurality of weirs 7 provided on the lower surface of the annular cavity 1. is injected into the annular cavity 1.
本発明においては、上記のように湯道３および堰６．７
を設けたため、その相乗作用により環状キャビテイ１外
周部の全周に溶湯がほぼ均一時間に流入し凝固するため
、特に歯車素材の歯成形部近傍における組織の均一が図
れるのである。In the present invention, as described above, the runner 3 and the weir 6.7
As a result of the synergistic action, the molten metal flows and solidifies all around the outer circumference of the annular cavity 1 in a substantially uniform time, so that the structure can be made uniform, especially in the vicinity of the tooth forming part of the gear material.
また、本発明においては、環状キャビティ１内に溶湯が
旋回しつつ流入するように堰を設けることが好ましく、
更に下面に形成する堰７は環状キャビティ１に対して同
心円状に配設することが組織の均一化を図る上でより好
ましい。Further, in the present invention, it is preferable to provide a weir so that the molten metal flows into the annular cavity 1 while swirling.
Furthermore, it is more preferable to arrange the weir 7 formed on the lower surface concentrically with respect to the annular cavity 1 in order to make the structure uniform.
第１表に示す化学成分（但し不可避的に混入する不純物
は表示せず）を有する球状黒鉛鋳鉄組成の溶湯を用い、
第１図に示す本発明方法と第２図に示す従来の方法で、
外径１９５ｍｍ、内径６０ｍｍ、厚さ３０ｍｍの歯車素
材をそれぞれ製造した。Using a molten metal with a composition of spheroidal graphite cast iron having the chemical components shown in Table 1 (however, impurities that are unavoidably mixed are not shown),
With the method of the present invention shown in FIG. 1 and the conventional method shown in FIG.
Gear materials each having an outer diameter of 195 mm, an inner diameter of 60 mm, and a thickness of 30 mm were manufactured.
第２表
第１表 （重量％）
このときの注湯温度は１，４００°Ｃであり、注湯速度
は１．４ｋｇ／ｓである。次に、この球状黒鉛鋳鉄製の
歯車素材を８７５°Ｃに加熱し、２時間保持した後、速
やかに３７５°Ｃの塩浴に浸漬し、２時間保持してベイ
ナイト変態させた後常温まで冷却した。Table 2 Table 1 (% by weight) The pouring temperature at this time was 1,400°C, and the pouring speed was 1.4 kg/s. Next, this spheroidal graphite cast iron gear material was heated to 875°C and held for 2 hours, then immediately immersed in a salt bath at 375°C, held for 2 hours to undergo bainite transformation, and then cooled to room temperature. did.
上記の工程で製造した歯車素材を第２表に示す歯車緒言
に加工を行った。The gear material produced in the above process was processed into the gear material shown in Table 2.
（以下、余白）
得られた歯車について、第４図Ｇこ示すようＧこ、９０
°ごとに歯４枚を選び各々の歯につ０て繰返し荷重を加
え、曲げ疲労試験を行った。その結果を第３表に示す。(Hereinafter, blank space) Regarding the obtained gear, as shown in Fig. 4, 90
A bending fatigue test was conducted by selecting four teeth at each angle and applying repeated loads to each tooth. The results are shown in Table 3.
表中の数字は繰返し数１０°回以上でも破断しない応力
を示す。The numbers in the table indicate the stress that does not cause breakage even when the number of repetitions is 10 degrees or more.
第３表で明らかなように、本発明の歯車Ｇま均一な疲労
強度を有し、歯車は最も弱し）部分で疲労力（決まるた
め本発明による歯車は従来法による歯車より約２０％の
曲げ疲労強度の向丘を得ること力（できる。尚、ここで
従来法歯車の疲労強度が本発明歯車に対し低いのは、湯
漬れの影響と考えられる。As is clear from Table 3, the gear G of the present invention has a uniform fatigue strength, and since the fatigue strength is determined at the weakest part of the gear, the gear according to the present invention has a fatigue strength of approximately 20% lower than that of the gear manufactured by the conventional method. The fatigue strength of the conventional gear is lower than that of the gear of the present invention, which is thought to be due to the effect of soaking in hot water.
次に本発明と従来法での組織の違いを説明する。Next, the difference in structure between the present invention and the conventional method will be explained.
第５図（ａ）は本発明方法の第１図により作製した歯車
素材の堰６付近Ａ部の組織を示す顕微鏡写真であり、第
５図（ｂ）は堰６付近の他の部分Ｂ部を示す。FIG. 5(a) is a micrograph showing the structure of a part A near the weir 6 of the gear material produced by the method shown in FIG. 1 of the present invention, and FIG. shows.
また、第６図（ｃ）は従来法の第２図により作製した歯
車素材の押し湯付近Ｃ部の組織を示す顕微鏡写真であり
、第６図（ｄ）は他の部分り部を示す。 第５図および
第６図から判るように、本実施例における歯車材の組織
は、基地組織がベイナイトとオーステナイトからなり、
該基地組織に黒く球状になっている黒鉛が分散した組織
構造のものである。従来方法により得られた歯車素材に
係る第６図（ｄ）は、冷却速度が他部より遅くなるため
黒鉛粒径が大きく、また球状化率は悪くなっている。こ
れに対し本発明歯車素材に係る第１図ＡおよびＢに示さ
れた第５図（ａ）および（ｂ）は、共に−様な黒鉛粒径
のものが分布しており、かつ球状化率も良好である。Moreover, FIG. 6(c) is a micrograph showing the structure of the C part near the riser of the gear material produced by the conventional method shown in FIG. 2, and FIG. 6(d) shows the other part. As can be seen from FIGS. 5 and 6, the structure of the gear material in this example is such that the base structure consists of bainite and austenite.
It has a structure in which black spherical graphite is dispersed in the matrix structure. In FIG. 6(d), which shows the gear material obtained by the conventional method, the cooling rate is slower than in other parts, so the graphite particle size is large and the spheroidization rate is poor. On the other hand, in FIGS. 5(a) and (b) shown in FIGS. 1A and 1B for the gear material of the present invention, the graphite particle size is distributed in a similar manner, and the spheroidization rate is is also good.
このように、本発明方法による歯車素材は、高強度歯車
素材として必要条件である組織の均一性が十分満足でき
るものである。As described above, the gear material produced by the method of the present invention fully satisfies the uniformity of the structure, which is a necessary condition for a high-strength gear material.
以上の説明で明らかなように、本発明方法によれば歯部
の各部分における組織が均一であるため、材料本来の特
性を十分活用することが出来、高強度でかつ信顧性の高
い歯車素材となる。As is clear from the above explanation, according to the method of the present invention, the structure in each part of the tooth portion is uniform, so the inherent characteristics of the material can be fully utilized, and the gear can be manufactured with high strength and high reliability. Becomes the material.
【図面の簡単な説明】
第１図は本発明歯車素材の製造法を示す図、第２図は従
来法歯車素材の製造法を示す図、第３図は従来法への対
策法の歯車素材の製造法を示すは第４図は歯の曲げ疲労
試験を行った歯の番号（Ｎ［Ｌ）を示す図、第５図は本
発明方法による歯車素材の金属組織を示す顕微鏡写真、
第６図は従来方法による歯車素材の金属組織を示す顕微
鏡写真である。
１：環状キャビティ、２：湯口、３：湯道、４：押し湯
、５，６，７． ８：堰、９：歯部。
（住）
区
（しン
’；；ｌ、１００
図
（ＣＩ）
’ｘ ｔｏ。[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a diagram showing the manufacturing method of the gear material of the present invention, Fig. 2 is a diagram showing the manufacturing method of the conventional gear material, and Fig. 3 is a diagram showing the gear material of the conventional method. Fig. 4 shows the manufacturing method of gear teeth, and Fig. 5 shows the tooth numbers (N[L) that were subjected to the tooth bending fatigue test.
FIG. 6 is a micrograph showing the metallographic structure of a gear material obtained by a conventional method. 1: annular cavity, 2: sprue, 3: runner, 4: riser, 5, 6, 7. 8: Weir, 9: Teeth. (Residence) ward (Shin';;l, 100 Figure (CI) 'x to.
Claims (1)
キャビティ下面に設けてある堰より押し上げ法により、
かつ同時に、前記縦湯道から前記環状キャビティ内面へ
放射状に出た堰とにより溶湯を注入し、歯部において、
球状黒鉛の粒径の分布が均一であり球状化率８５％以上
で黒鉛粒径が７０μｍ以下を特徴とする球状黒鉛鋳鉄歯
車素材の製造法。A vertical runner is provided in the center of the annular cavity in the mold, and by pushing up from a weir provided on the lower surface of the annular cavity,
At the same time, molten metal is injected from the vertical runner through a weir extending radially to the inner surface of the annular cavity, and at the tooth part,
A method for producing a spheroidal graphite cast iron gear material, characterized in that the particle size distribution of spheroidal graphite is uniform, the spheroidization rate is 85% or more, and the graphite particle size is 70 μm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3016889A JPH02209413A (en) | 1989-02-09 | 1989-02-09 | Manufacture of spheroidal graphite case iron gear raw material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3016889A JPH02209413A (en) | 1989-02-09 | 1989-02-09 | Manufacture of spheroidal graphite case iron gear raw material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02209413A true JPH02209413A (en) | 1990-08-20 |
Family
ID=12296224
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3016889A Pending JPH02209413A (en) | 1989-02-09 | 1989-02-09 | Manufacture of spheroidal graphite case iron gear raw material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02209413A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004323087A (en) * | 2003-04-28 | 2004-11-18 | Toppan Printing Co Ltd | Square cup-shaped plastic container |
| CN104789796A (en) * | 2015-05-18 | 2015-07-22 | 浙江鑫耐铝熔铸设备材料有限公司 | Graphite rotor |
-
1989
- 1989-02-09 JP JP3016889A patent/JPH02209413A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004323087A (en) * | 2003-04-28 | 2004-11-18 | Toppan Printing Co Ltd | Square cup-shaped plastic container |
| CN104789796A (en) * | 2015-05-18 | 2015-07-22 | 浙江鑫耐铝熔铸设备材料有限公司 | Graphite rotor |
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