JPH0453937B2 - - Google Patents
Info
- Publication number
- JPH0453937B2 JPH0453937B2 JP22984182A JP22984182A JPH0453937B2 JP H0453937 B2 JPH0453937 B2 JP H0453937B2 JP 22984182 A JP22984182 A JP 22984182A JP 22984182 A JP22984182 A JP 22984182A JP H0453937 B2 JPH0453937 B2 JP H0453937B2
- Authority
- JP
- Japan
- Prior art keywords
- weight
- steel
- carburizing
- strain
- heat 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.)
- Expired
Links
- 229910000831 Steel Inorganic materials 0.000 claims description 28
- 239000010959 steel Substances 0.000 claims description 28
- 238000005255 carburizing Methods 0.000 claims description 20
- 229910052748 manganese Inorganic materials 0.000 claims description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- 229910052804 chromium Inorganic materials 0.000 claims description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims description 4
- 239000012535 impurity Substances 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 description 22
- 238000005275 alloying Methods 0.000 description 12
- 230000000694 effects Effects 0.000 description 9
- 239000000463 material Substances 0.000 description 8
- 238000010791 quenching Methods 0.000 description 8
- 230000000171 quenching effect Effects 0.000 description 8
- 230000007423 decrease Effects 0.000 description 7
- 238000009661 fatigue test Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000011282 treatment Methods 0.000 description 5
- 238000005452 bending Methods 0.000 description 4
- 239000006185 dispersion Substances 0.000 description 4
- 239000000203 mixture Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229910001566 austenite Inorganic materials 0.000 description 2
- 229910001563 bainite Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 229910000734 martensite Inorganic materials 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 238000010273 cold forging Methods 0.000 description 1
- 238000012669 compression test Methods 0.000 description 1
- 230000003009 desulfurizing effect Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000009931 harmful effect Effects 0.000 description 1
- 229910052745 lead Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Landscapes
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
Description
本発明は、熱処理歪量及びそのばらつきの少な
い浸炭用鋼に関する。
歯車や軸受等の鋼製品は、耐磨耗性や耐疲労性
の改善を目的として浸炭焼入れ等の表面硬化処理
がなされることが多いが、この際に熱処理歪が不
可避的に発生し、しかも、上記浸炭処理が部品加
工の最終工程であるため、上記熱処理歪がそのま
ま製品に残されて、強度の低下等の有害な影響と
なつて現われる。このような問題を解決するため
に、焼入れの際に拘束治具を用いたり、或いは熱
処理歪の少ない焼入れ液を用いる等の方法により
熱処理歪の低減を図り、又は浸炭処理後に矯正を
行なう等の方法を採用しているが、いずれも多大
の費用と労力を要する問題がある。特に、例え
ば、自動車産業に代表されるように、省エネルギ
ーを背景として、部品の軽量化が推進されている
最近においては、部品は小型化、薄肉化する傾向
が強いが、このように部品を薄肉化した場合に、
上記の浸炭処理後の熱処理歪が大きくなるので、
従来にも増して熱処理歪の少ない浸炭用鋼が要望
されるに至つている。
一般に、鋼におけるＣ及びその他の合金元素の
含有量を増すとき、その焼入れ性が高まつて、焼
入れ時にマルテンサイトやベーナイト組織の生成
量が多くなるために、芯部硬さが増すと共に熱処
理歪が増大する。本発明者らはかかる事実に鑑
み、鋼におけるＣ、Mn及びその他の合金元素の
含有量によつて本発明によつて規定される焼入れ
性パラメータ（以下、D〓と称することがある。）
が、上記各合金元素の含有量が所定範囲にあると
きは、その含有量の変動にもかかわらず、熱処理
歪挙動、特に熱処理歪率とそのばらつきがD〓に
より連続関数的に規制されることを見出して、本
発明に至つたものである。
本発明による熱処理歪量及びそのばらつきの少
ない浸炭用鋼は、C0.22〜0.28重量％、Si0.35重量
％以下及びMn0.30〜1.5重量％を含有すると共
に、Al0.020重量％以上、0.050重量％未満及び
Ti0.005〜0.050重量％から選ばれる少なくとも１
種の元素と、Cr0.30〜1.50重量％とを含有し、残
部鉄及び不可避的不純物よりなり、且つ、上記元
素によつて次式で規定される焼入れ性パラメータ
D〓＝25.4×（1.3％Ｃ＋0.1）×（2.1％Mn＋0.6）×（1
.4％Cr＋0.7）×（2.5％Mo＋1.0）
（但し、％元素はその元素の重量％を示す。）
が35〜45（mm）の範囲にあることを特徴とする。
通常、浸炭用鋼においては、芯部強度や靱性を
考慮して、Ｃ量は0.12〜0.25重量％であるが、一
般にＣは焼入れ性を介して熱処理歪に関与するば
かりでなく、マルテンサイトやベーナイト等の中
間組織の結晶格子定数を変化させるため、他の合
金元素に比べて熱処理歪に与える影響が大きい。
本発明者らの実験によれば、Ｃ量が増せば歪量は
低減するが、歪のばらつきが大きくなるため、歪
が低位で安定するためには、0.22〜0.28重量％の
範囲にあることを要する。
Siは溶製時の脱酸元素として0.05重量％以上が
必要であるが、余りに多量に含有するときは、冷
間鍛造等の加工性が低下し、また、疲労強度も低
下するので、0.35重量％を上限とする。
Mnも脱酸脱硫元素として、また、焼入れ性を
増大させて、芯部強度を向上させるために0.30重
量％以上を含有する必要があるが、余りに多量に
含有するときは、芯部強度が高くなりすぎると共
に、後述する本発明による焼入れ性パラメータ
D〓を過度に大きくして歪量を大きくするので、
1.50重量％を上限とする。
Alは一般に浸炭加熱時のオーステナイト結晶
粒の成長を抑制する効果をもつが、0.020重量％
未満ではこの効果が殆ど発現されず、一方、
0.050重量％以上に多量に含有させても、上記効
果が飽和し、また、却つて転動疲労性を劣化させ
るアルミナ系介在物量も増すので、Al量は、
0.050重量％未満とする。
Tiも、Alと同様にいずれも浸炭加熱時のオー
ステナイト結晶粒の成長を抑制する効果をもつ
が、この効果が有効に発現されるためには、いず
れの元素についても0.005重量％以上含有させる
ことを要する。しかし、0.05重量％を越えて多量
に含有させても上記効果が飽和する。
Crは鋼の焼入れ性を向上させる合金元素であ
つて、0.30重量％以上を含有させるときにその効
果が有効に発現されるが、余りに多量に含有させ
るときは、芯部硬さが高くなりすぎたり、また、
表面に異常組織が生じたりするので、その上限は
1.50重量％とする。
かかる化学成分組成を有する本発明による浸炭
用鋼は、更に、これら合金元素の鋼における含有
量によつて次式で規定される焼入れ性パラメータ
D〓＝25.4×（1.3％Ｃ＋0.1）×（2.1％Mn＋0.6）×（1
.4％Cr＋0.7）×（2.5％Mo＋1.0）
（但し、％元素はその元素の重量％を示す。以
下、同じ。）
が35〜45mmの範囲にあることを要する。
即ち、本発明者らの広範な実験による結果、上
記合金元素の含有量が上記所定範囲にあるとき、
その含有量の変動にかかわらず、歪量と歪のばら
つきがD〓に対して連続関数的に変化し、D〓が35
〜45mmの範囲にあるとき、歪を低位に安定させる
ことができる。D〓が35mmよりも小さいときは、
歪量は少なくなるが、そのばらつきが大きくな
り、一方、D〓が45mmよりも大きいときは、歪の
ばらつきは小さくなるが、歪量が大きくなる。
本発明による熱処理歪量及びそのばらつきの少
ない浸炭用鋼は、上記合金元素に加えて、S0.03
〜0.40重量％、Pb0.05〜0.35重量％及びZr0.05〜
0.20重量％から選ばれる少なくとも１種の元素と
を含有していてもよい。
これらＳ、Pb及びZrはいずれも被削性を向上
させる合金元素であるが、その効果が有効に認め
られるのは、Ｓについては0.03重量％以上、Pbに
ついては0.05重量％以上、また、Zrについては
0.05重量％以上である。しかし、余りに多量に含
有させるときは、鋼の強度特性を劣化させ、ま
た、被削性についても飽和現象が認められるの
で、その上限をS0.40重量％、Pb0.35重量％、
Zr0.20重量％とする。
以上のように、本発明の浸炭用鋼は、特定の合
金元素を特定の範囲で含有すると共に、これら合
金元素の含有量によつて規定される前記焼入れ性
パラメータD〓を所定の範囲とすることによつて、
熱処理後の歪を低位に安定させることができる。
以下に実施例を挙げて本発明を説明するが、本
発明はこれら実施例により何ら限定されるもので
はない。
実施例 １
第１表に示す化学成分と焼入れ性パラメータ
D〓とを有する種々の鋼材を高周波炉にて溶製し、
この鋼材を1150℃に加熱して熱間鍛造し、直径80
mmの丸棒に加工し、これを925℃で２時間加熱し
た後、空気中で放冷する焼ならし処理をし、次
に、第１図に示すように、高さ25mm、内径58mm、
最少外径62mm、最大外径71mmであつて、胴部中央
部に幅７mm、深さ4.5mmの環状溝を有する薄肉円
筒型の歪試験片に加工した後、925℃で３時間加
熱して浸炭、油焼入れ（油温40／60℃、Ｈ値
0.50in-1）を施した。この試験片について、浸炭
焼入れ処理前後の図示した内径の変化から歪量を
測定し、また、そのばらつきを標準偏差で求め
た。結果を第１表及び第２図に示す。第２図より
歪量及びそのばらつきがD〓に対して連続関数的
に変化し、D〓が35〜45mmの範囲にあるときに歪
を低位に安定させることができることが明らかで
ある。
実施例 ２
SCr420を素材鋼として、本発明による鋼材と、
比較鋼、即ち、D〓は本発明の範囲内にあるが、
合金元素含有量が本発明の範囲外にある鋼材及び
D〓が本発明の範囲外であるが、合金元素含有量
が本発明の範囲内にある鋼材とを実施例１と同様
にして溶製した。これら鋼材の化学成分及びD〓
を第２表に示す。
これら鋼材を用いて実施例１と同様にして試験
片を加工し、同様にして浸炭焼入れ（油温度
110／130℃、Ｈ値0.20in-1）による熱処理歪の挙
動を調べた。結果を第２表に示す。
本発明の浸炭用鋼によれば、熱処理歪量及びそ
のばらつきが少なく、歪が低位に安定しているこ
とが明らかである。
The present invention relates to a steel for carburizing with less heat treatment strain and its variation. Steel products such as gears and bearings are often subjected to surface hardening treatments such as carburizing and quenching to improve wear resistance and fatigue resistance, but heat treatment distortion inevitably occurs during this process. Since the above-mentioned carburizing treatment is the final process of parts processing, the above-mentioned heat treatment distortion remains in the product as it is, resulting in harmful effects such as a decrease in strength. In order to solve these problems, methods such as using a restraint jig during quenching, or using a quenching fluid with less heat treatment distortion are used to reduce heat treatment distortion, or straightening is performed after carburizing treatment. However, each method has the problem of requiring a large amount of cost and labor. Particularly in recent years, as exemplified by the automobile industry, where weight reduction of parts is being promoted due to energy conservation, there is a strong tendency for parts to become smaller and thinner. If the
Since the heat treatment distortion after the above carburizing treatment increases,
There is a growing demand for carburizing steel with less heat treatment distortion than ever before. Generally, when the content of C and other alloying elements in steel is increased, its hardenability increases and the amount of martensite and bainite structures generated during hardening increases, resulting in an increase in core hardness and heat treatment strain. increases. In view of this fact, the present inventors have developed a hardenability parameter (hereinafter sometimes referred to as D〓) defined by the present invention based on the content of C, Mn, and other alloying elements in steel.
However, when the content of each of the above alloying elements is within a predetermined range, the heat treatment strain behavior, especially the heat treatment strain rate and its dispersion, are regulated in a continuous function manner by D〓, despite fluctuations in the content. This discovery led to the present invention. The carburizing steel according to the present invention with a small amount of heat treatment strain and its variation contains 0.22 to 0.28 weight % of C, 0.35 weight % or less of Si, and 0.30 to 1.5 weight % of Mn, and 0.020 weight % or more of Al. Less than 0.050% by weight and
At least 1 selected from Ti0.005 to 0.050% by weight
hardenability parameter D = 25.4 x (1.3% C+0.1)×(2.1%Mn+0.6)×(1
.4% Cr + 0.7) x (2.5% Mo + 1.0) (However, % element indicates the weight % of the element.) is in the range of 35 to 45 (mm). Normally, in steel for carburizing, the amount of C is 0.12 to 0.25% by weight in consideration of core strength and toughness, but in general, C not only participates in heat treatment distortion through hardenability, but also contributes to martensite and Because it changes the crystal lattice constant of intermediate structures such as bainite, it has a greater effect on heat treatment strain than other alloying elements.
According to the experiments conducted by the present inventors, as the amount of C increases, the amount of strain decreases, but the variation in strain increases, so in order for the strain to be stable at a low level, it must be in the range of 0.22 to 0.28% by weight. It takes. 0.05% by weight or more of Si is required as a deoxidizing element during ingot manufacturing, but if it is contained in too large a quantity, workability in cold forging etc. will decrease and fatigue strength will also decrease, so 0.35% by weight The upper limit is %. Mn must also be contained in an amount of 0.30% by weight or more as a deoxidizing and desulfurizing element, and in order to increase hardenability and improve core strength, but if it is contained in too large a quantity, the core strength will be high. hardenability parameters according to the present invention, which will be described later.
By increasing D〓 excessively and increasing the amount of distortion,
The upper limit is 1.50% by weight. Al generally has the effect of suppressing the growth of austenite crystal grains during carburizing heating, but 0.02% by weight
Below this level, this effect is hardly manifested;
Even if it is contained in a large amount of 0.050% by weight or more, the above effects will be saturated, and the amount of alumina-based inclusions that deteriorate rolling fatigue properties will also increase, so the amount of Al is
Less than 0.050% by weight. Like Al, both Ti and Al have the effect of suppressing the growth of austenite grains during carburizing heating, but in order for this effect to be effectively expressed, each element must be contained at 0.005% by weight or more. It takes. However, even if the content exceeds 0.05% by weight, the above effects will be saturated. Cr is an alloying element that improves the hardenability of steel, and its effect is effectively expressed when it is contained in an amount of 0.30% by weight or more, but if it is contained in an excessively large amount, the core hardness becomes too high. Or, again,
Since abnormal tissue may occur on the surface, the upper limit is
1.50% by weight. The carburizing steel of the present invention having such a chemical composition further has a hardenability parameter D=25.4×(1.3%C+0.1)×( 2.1%Mn+0.6)×(1
.4% Cr + 0.7) x (2.5% Mo + 1.0) (However, % element indicates the weight % of the element. The same applies hereinafter) is required to be in the range of 35 to 45 mm. That is, as a result of extensive experiments by the present inventors, when the content of the alloying element is within the above predetermined range,
Regardless of the variation in its content, the amount of strain and the variation in strain change as a continuous function with respect to D〓, and D〓 is 35
When it is in the range of ~45mm, the distortion can be stabilized at a low level. When D〓 is smaller than 35mm,
The amount of distortion decreases, but its dispersion increases.On the other hand, when D〓 is larger than 45 mm, the dispersion of distortion decreases, but the amount of distortion increases. The carburizing steel according to the present invention has a small amount of heat treatment strain and its variation, in addition to the above alloying elements, S0.03
~0.40wt%, Pb0.05~0.35wt% and Zr0.05~
It may contain at least one element selected from 0.20% by weight. These S, Pb, and Zr are all alloying elements that improve machinability, but their effects are effectively recognized when S is 0.03% by weight or more, Pb is 0.05% by weight or more, and Zr about
It is 0.05% by weight or more. However, if too large amounts are contained, the strength characteristics of the steel deteriorate and saturation phenomenon is observed in machinability.
Zr shall be 0.20% by weight. As described above, the carburizing steel of the present invention contains specific alloying elements in a specific range, and the hardenability parameter D〓 defined by the content of these alloying elements is in a predetermined range. By the way,
Distortion after heat treatment can be stabilized at a low level. The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples in any way. Example 1 Chemical composition and hardenability parameters shown in Table 1
Various steel materials with D〓 are melted in a high frequency furnace,
This steel material is heated to 1150℃ and hot forged to create a diameter of 80mm.
mm round bar, heated at 925°C for 2 hours, then normalized by cooling in air. Next, as shown in Figure 1, the bar is 25 mm in height, 58 mm in inner diameter,
After processing into a thin cylindrical strain test piece with a minimum outer diameter of 62 mm and a maximum outer diameter of 71 mm, and an annular groove with a width of 7 mm and a depth of 4.5 mm in the center of the body, it was heated at 925°C for 3 hours. Carburizing, oil quenching (oil temperature 40/60℃, H value
0.50in -1 ) was applied. For this test piece, the amount of strain was measured from the change in the inner diameter shown before and after the carburizing and quenching treatment, and the variation thereof was determined as a standard deviation. The results are shown in Table 1 and Figure 2. It is clear from FIG. 2 that the amount of strain and its dispersion change in a continuous function with respect to D〓, and that when D〓 is in the range of 35 to 45 mm, the strain can be stabilized at a low level. Example 2 Using SCr420 as the material steel, the steel material according to the present invention,
Although the comparative steel, namely D〓, is within the scope of the present invention,
Steel materials whose alloying element content is outside the range of the present invention and
A steel material whose alloying element content was outside the range of the present invention but within the range of the present invention was produced in the same manner as in Example 1. Chemical composition and D〓 of these steel materials
are shown in Table 2. Using these steel materials, test pieces were processed in the same manner as in Example 1, and carburized and quenched (oil temperature
The behavior of heat treatment strain at 110/130°C and H value of 0.20 in -1 was investigated. The results are shown in Table 2. According to the steel for carburizing of the present invention, it is clear that the amount of heat treatment strain and its variation are small, and the strain is stable at a low level.
【表】【table】
【表】【table】
【表】
実施例 ３
C0.23重量％、Si0.27重量％、Mn0.58重量％、
Cr0.99重量％、Al0.031重量％、残部鉄及び不可
避的不純物よりなる鋼を高周波炉にて溶製し、熱
間鍛造にて直径25mmの丸棒に鍛造した。次いで、
925℃で30分加熱した後、空気中にて放冷して、
焼きならし処理を行なつた。これを更に直径20
mm、高さ30mmの丸棒に機械加工し、端面拘束圧縮
試験を行なつて、据込み時の変形抵抗と割れが発
生し始める限界据込み率を求めた。
また、平行部の直径が８mmの平滑疲労試験片を
機械加工し、925℃×３時間／油焼入れ、180℃×
２時間／空冷の条件で浸炭焼入れ、焼戻しを行な
つた後、回転曲げ疲労試験を行なつた。
変形抵抗は81Kgｆ／mm2、限界据込み率は80％、
疲労限度は72Kgｆ／mm2であつた。また、回転曲
げ疲労試験の結果を第３図に示す。
比較のために、C0.24重量％、Si0.54重量％、
Mn0.63重量％、Cr1.02重量％、Al0.027重量％、
残部鉄及び不可避的不純物よりなる鋼を用いた以
外は、上記と同様して、試験を行なつたところ、
変形抵抗は87Kgｆ／mm2、限界据込み率は70％、
疲労限度は62Kgｆ／mm2であつた。回転曲げ疲労
試験の結果は、第３図に示す。
以上の結果から、Si量が0.5重量％を越えると
き、冷間鍛造性及び疲労強度が低下することが示
される。[Table] Example 3 C0.23% by weight, Si0.27% by weight, Mn0.58% by weight,
A steel consisting of 0.99% by weight of Cr, 0.031% by weight of Al, the balance iron and unavoidable impurities was melted in a high frequency furnace and hot forged into a round bar with a diameter of 25 mm. Then,
After heating at 925℃ for 30 minutes, let it cool in the air.
A normalizing process was performed. Add this further to a diameter of 20
A round bar with a diameter of 30 mm and a height of 30 mm was machined, and an end face restraint compression test was performed to determine the deformation resistance during upsetting and the critical upsetting rate at which cracks begin to occur. In addition, a smooth fatigue test piece with a parallel part diameter of 8 mm was machined, 925℃ x 3 hours / oil quenching, 180℃ x
After carburizing and quenching and tempering under the conditions of 2 hours/air cooling, a rotary bending fatigue test was conducted. Deformation resistance is 81Kgf/mm 2 , limit upsetting rate is 80%,
The fatigue limit was 72Kgf/ mm2 . Furthermore, the results of the rotating bending fatigue test are shown in FIG. For comparison, C0.24wt%, Si0.54wt%,
Mn0.63% by weight, Cr1.02% by weight, Al0.027% by weight,
Tests were conducted in the same manner as above, except that steel consisting of residual iron and unavoidable impurities was used.
Deformation resistance is 87Kgf/mm 2 , limit upsetting rate is 70%,
The fatigue limit was 62Kgf/ mm2 . The results of the rotating bending fatigue test are shown in Figure 3. The above results show that when the amount of Si exceeds 0.5% by weight, cold forgeability and fatigue strength decrease.
第１図は浸炭焼入れによる熱処理歪の挙動を調
べるために本発明において用いた試験用円筒を示
す断面図、第２図は本発明による焼入れ性パラメ
ータD〓と熱処理歪との関係を示すグラフ、第３
図は本発明鋼と比較鋼について、回転曲げ疲労試
験の結果を示すグラフである。
FIG. 1 is a sectional view showing a test cylinder used in the present invention to investigate the behavior of heat treatment strain due to carburizing and quenching, and FIG. 2 is a graph showing the relationship between the hardenability parameter D〓 and heat treatment strain according to the present invention. Third
The figure is a graph showing the results of a rotating bending fatigue test on the steel of the present invention and the comparative steel.
Claims (1)
Mn0.30〜1.5重量％を含有すると共に、Al0.020重
量％以上、0.050重量％未満及びTi0.005〜0.050重
量％から選ばれる少なくとも１種の元素と、
Cr0.30〜1.50重量％とを含有し、残部鉄及び不可
避的不純物よりなり、且つ、上記元素によつて次
式で規定される焼入れ性パラメータ D〓＝25.4×（1.3％Ｃ＋0.1）×（2.1％Mn＋0.6）×（1
.4％Cr＋0.7）×（2.5％Mo＋1.0） （但し、％元素はその元素の重量％を示す。） が35〜45（mm）の範囲にあることを特徴とする熱
処理歪量及びそのばらつきの少ない浸炭用鋼。 ２ C0.22〜0.28重量％、Si0.35重量％以下及び
Mn0.30〜1.5重量％を含有すると共に、Al0.020重
量％以上、0.050重量％未満及びTi0.005〜0.050重
量％から選ばれる少なくとも１種の元素と、
Cr0.30〜1.50重量％と、S0.03〜0.40重量％、
Pb0.05〜0.35重量％及びZr0.05〜0.20重量％から
選ばれる少なくとも１種の元素とを含有し、残部
鉄及び不可避的不純物よりなり、且つ、上記元素
によつて次式で規定される焼入れ性パラメータ D〓＝25.4×（1.3％Ｃ＋0.1）×（2.1％Mn＋0.6）×（1
.4％Cr＋0.7）×（2.5％Mo＋1.0） （但し、％元素はその元素の重量％を示す。） が35〜45（mm）の範囲にあることを特徴とする熱
処理歪量及びそのばらつきの少ない浸炭用鋼。[Claims] 1 C0.22 to 0.28% by weight, Si 0.35% by weight or less, and
Contains 0.30 to 1.5% by weight of Mn, and at least one element selected from 0.020% by weight or more of Al, less than 0.050% by weight of Ti, and 0.005% to 0.050% by weight of Ti;
hardenability parameter D = 25.4 x (1.3% C + 0.1) x (2.1%Mn+0.6)×(1
.4% Cr + 0.7) x (2.5% Mo + 1.0) (However, % element indicates the weight % of the element.) is in the range of 35 to 45 (mm). Steel for carburizing with less variation. 2 C0.22 to 0.28% by weight, Si 0.35% by weight or less, and
Contains 0.30 to 1.5% by weight of Mn, and at least one element selected from 0.020% by weight or more of Al, less than 0.050% by weight of Ti, and 0.005% to 0.050% by weight of Ti;
Cr0.30~1.50wt%, S0.03~0.40wt%,
Contains at least one element selected from 0.05 to 0.35% by weight of Pb and 0.05 to 0.20% by weight of Zr, with the balance consisting of iron and unavoidable impurities, and is defined by the following formula according to the above elements. Hardenability parameter D=25.4×(1.3%C+0.1)×(2.1%Mn+0.6)×(1
.4% Cr + 0.7) x (2.5% Mo + 1.0) (However, % element indicates the weight % of the element.) is in the range of 35 to 45 (mm). Steel for carburizing with less variation.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22984182A JPS59123743A (en) | 1982-12-28 | 1982-12-28 | Carburizing steel producing slight strain due to heat treatment |
| JP22111189A JPH02277744A (en) | 1982-12-28 | 1989-08-28 | Bar steel for carburizing low in amount of heat treating strain and its variance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22984182A JPS59123743A (en) | 1982-12-28 | 1982-12-28 | Carburizing steel producing slight strain due to heat treatment |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22111189A Division JPH02277744A (en) | 1982-12-28 | 1989-08-28 | Bar steel for carburizing low in amount of heat treating strain and its variance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59123743A JPS59123743A (en) | 1984-07-17 |
| JPH0453937B2 true JPH0453937B2 (en) | 1992-08-28 |
Family
ID=16898517
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22984182A Granted JPS59123743A (en) | 1982-12-28 | 1982-12-28 | Carburizing steel producing slight strain due to heat treatment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59123743A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02277744A (en) * | 1982-12-28 | 1990-11-14 | Kobe Steel Ltd | Bar steel for carburizing low in amount of heat treating strain and its variance |
| JPS61210154A (en) * | 1985-03-13 | 1986-09-18 | Kobe Steel Ltd | Low strain carburizing steel |
| US5746842A (en) | 1995-09-29 | 1998-05-05 | Toa Steel Co., Ltd. | Steel gear |
| JP4778626B2 (en) * | 2001-04-03 | 2011-09-21 | 株式会社神戸製鋼所 | Manufacturing method of steel parts with low heat treatment strain |
| FR2935988B1 (en) * | 2008-09-12 | 2010-10-08 | Ascometal Sa | STEEL, IN PARTICULAR FOR BEARINGS AND MECHANICAL PARTS SUITABLE FOR CEMENTATION OR CARBONITURATION, AND PARTS PRODUCED WITH SAID STEEL. |
-
1982
- 1982-12-28 JP JP22984182A patent/JPS59123743A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59123743A (en) | 1984-07-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7763123B2 (en) | Spring produced by a process comprising coiling a hard drawn steel wire excellent in fatigue strength and resistance to setting | |
| JP4632931B2 (en) | Induction hardening steel excellent in cold workability and its manufacturing method | |
| WO2004029314A1 (en) | Machine part and method for manufacturing same | |
| JPH0790363A (en) | Production of machine structural part excellent in mechanical strength | |
| JPH0971841A (en) | Steel for soft-nitriding | |
| US5985044A (en) | Forged, non-heat treated, nitrided steel parts and process of making | |
| JPH0453937B2 (en) | ||
| WO2018180342A1 (en) | Shaft member | |
| JPH1162943A (en) | Soft nitrided as rolled or normalized crankshaft and manufacture thereof | |
| JPH0254416B2 (en) | ||
| US6391124B1 (en) | Non-heat treated, soft-nitrided steel parts | |
| JP3579558B2 (en) | Bearing steel with excellent resistance to fire cracking | |
| JP2614653B2 (en) | Manufacturing method of carburized parts with little heat treatment distortion | |
| JPH1046287A (en) | Steel for nitriding and production of nitriding steel product | |
| JPH09279296A (en) | Steel for soft-nitriding excellent in cold forgeability | |
| KR101984041B1 (en) | Case hardening steel | |
| JP2001049337A (en) | Production of high strength spring excellent in fatigue strength | |
| JPH0860294A (en) | Production of parts for machine structural use, excellent in fatigue strength, and case hardening steel for producing pertinent parts for machine structural use | |
| JPH04297548A (en) | High strength and high toughness non-heat treated steel and its manufacture | |
| JPH0559432A (en) | Production of carburized gear excellent in fatigue strength | |
| JP6394844B1 (en) | Shaft member | |
| JPS61210154A (en) | Low strain carburizing steel | |
| KR100501680B1 (en) | Heat treatment method of boron alloys for gear | |
| JPS60262941A (en) | Steel for warm forging | |
| JPH02217421A (en) | Production of spring with high fatigue strength and steel wire for use therein |