JPH06256897A - Steel for hot forging die - Google Patents
Steel for hot forging dieInfo
- Publication number
- JPH06256897A JPH06256897A JP5067537A JP6753793A JPH06256897A JP H06256897 A JPH06256897 A JP H06256897A JP 5067537 A JP5067537 A JP 5067537A JP 6753793 A JP6753793 A JP 6753793A JP H06256897 A JPH06256897 A JP H06256897A
- Authority
- JP
- Japan
- Prior art keywords
- steel
- toughness
- present
- less
- die
- 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
- 239000010959 steel Substances 0.000 title claims abstract description 42
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 41
- 238000005242 forging Methods 0.000 title claims abstract description 22
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 7
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 6
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 6
- 239000012535 impurity Substances 0.000 claims abstract description 5
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 4
- 229910052748 manganese Inorganic materials 0.000 claims abstract 2
- 229910052742 iron Inorganic materials 0.000 claims 1
- 238000011161 development Methods 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 4
- 238000012360 testing method Methods 0.000 description 8
- 230000007423 decrease Effects 0.000 description 7
- 239000000463 material Substances 0.000 description 7
- 230000007704 transition Effects 0.000 description 6
- 230000035882 stress Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000010791 quenching Methods 0.000 description 4
- 230000000171 quenching effect Effects 0.000 description 4
- 229910001315 Tool steel Inorganic materials 0.000 description 3
- 238000007656 fracture toughness test Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000005121 nitriding Methods 0.000 description 3
- 229910001563 bainite Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 229910000734 martensite Inorganic materials 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process 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
- 238000005520 cutting process Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000009863 impact test Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 229910001562 pearlite Inorganic materials 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 229920001169 thermoplastic Polymers 0.000 description 1
- 239000004416 thermosoftening plastic Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Landscapes
- Forging (AREA)
Abstract
(57)【要約】
【構成】 重量％で、Ｃ：０．２５〜０．４５％、Ｓ
ｉ：０．５０％以下、Ｍｎ：０．２０〜１．０％、Ｐ：
０．０１５％以下、Ｓ：０．００５％以下、Ｎｉ：０．
５〜２．０％、Ｃｒ：２．８〜４．２％、Ｍｏ：１．０
〜２．０％、Ｖ：０．１〜０．５％、残部はＦｅおよび
不可避的不純物より構成する。
【効果】 高温強度、靱性に優れた鋼を提供することが
でき、熱間鍛造金型鋼として使用時には、ヒートチェッ
ク、亀裂の進展、大割れに対して改善されているので、
従来よりも寿命の長い金型を提供することができる。(57) [Summary] [Structure] Weight%, C: 0.25 to 0.45%, S
i: 0.50% or less, Mn: 0.20 to 1.0%, P:
0.015% or less, S: 0.005% or less, Ni: 0.
5 to 2.0%, Cr: 2.8 to 4.2%, Mo: 1.0
.About.2.0%, V: 0.1 to 0.5%, the balance being Fe and inevitable impurities. [Effect] It is possible to provide a steel having excellent high temperature strength and toughness, and when used as a hot forging die steel, it is improved against heat check, crack development, and large crack.
It is possible to provide a mold having a longer life than conventional ones.
Description
【０００１】[0001]
【産業上の利用分野】本発明は、高負荷、高速の熱間鍛
造プレス型などに供される金型用鋼に関するものであ
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel for a die used for a hot forging press die having a high load and a high speed.
【０００２】[0002]
【従来の技術】一般的には、ＪＩＳ Ｇ ４４０４に規
定されたＳＫＴ４、ＳＫＤ６１の合金工具鋼が鋼、アル
ミニウム合金などの熱間鍛造用金型に使用されている。2. Description of the Related Art Generally, SKT4 and SKD61 alloy tool steels defined in JIS G 4404 are used for hot forging dies such as steel and aluminum alloys.
【０００３】[0003]
【発明が解決しようとする課題】熱間鍛造用金型に生じ
る損傷は、熱間被加工物と金型の摩擦による金型型口
の磨耗、金型表面で急加熱、急冷却が繰り返されるこ
とにより生ずる熱塑性歪による亀裂（ヒートチェッ
ク）、成形荷重などの機械的応力による亀裂の進展と
大割れである。The damage that occurs in the hot forging die is repeated wear of the die mouth due to friction between the hot work piece and the die, rapid heating and rapid cooling on the die surface. These are cracks (heat check) due to thermoplastic strain caused by the above, and crack development and large cracks due to mechanical stress such as molding load.
【０００４】金型の損傷を改善するために、ＳＫＴ４あ
るいはＳＫＤ６１の材質改善、金型素材製造技術の改
善、窒化などの金型表面処理による改善が行われてい
る。しかしながら、鍛造サイクルの高速化、鍛造製品形
状の複雑化など金型使用条件が厳しくなり、結果とし
て、前記した改善が行われているにもかかわらず金型寿
命は短命化しているのが現状である。In order to improve the damage to the mold, the material of SKT4 or SKD61 has been improved, the technology for manufacturing the mold material has been improved, and the surface of the mold such as nitriding has been improved. However, in the current situation, the mold use conditions become stricter, such as faster forging cycle and complicated forged product shape, and as a result, the life of the mold is shortened despite the above improvements. is there.
【０００５】また、鍛造サイクルの高速化、鍛造製品形
状の複雑化により、金型の主な廃却原因は従来の磨耗か
ら亀裂へと変わっている。特に、亀裂の進展に関する主
な原因は低サイクルの材料疲労である。Further, due to the speeding up of the forging cycle and the complicated shape of the forged product, the main cause of scrapping of the die has changed from conventional wear to cracking. In particular, the main cause for crack growth is low cycle material fatigue.
【０００６】本発明の目的は、鍛造サイクルの高速化、
鍛造製品形状の複雑化など厳しい金型使用条件下におい
てもヒートチェック、亀裂の進展（低サイクル疲労）、
大割れに対して優れた熱間鍛造金型用鋼を提供すること
である。The object of the present invention is to speed up the forging cycle,
Heat check, crack development (low cycle fatigue), even under severe mold use conditions such as complicated forged product shape,
An object of the present invention is to provide a hot forging die steel which is excellent against large cracks.
【０００７】[0007]
【課題を解決するための手段】前記した本発明の目的を
達成するために、本発明者等は、鋭意実験、研究を重ね
た結果、熱間鍛造金型用鋼の亀裂の発生および進展を抑
えるには、以下に示す条件を満足することが有効である
ことを知見した。[Means for Solving the Problems] In order to achieve the above-mentioned object of the present invention, the inventors of the present invention have conducted diligent experiments and researches, and as a result, It was found that it is effective to satisfy the following conditions to suppress it.
【０００８】一般に、熱間鍛造金型用鋼の亀裂の進展
（低サイクル疲労）に対しては、工具鋼の耐力、延性
（引張破断絞り）、靱性（破壊靱性値）が影響を及ぼす
ことが知られている。Generally, the crack propagation (low cycle fatigue) of hot forging die steel is affected by the yield strength, ductility (tensile fracture drawing) and toughness (fracture toughness value) of the tool steel. Are known.
【０００９】しかし、本発明者等は金型の亀裂調査、熱
応力、機械的応力の解析、金型用鋼の亀裂進展試験を行
った結果、亀裂の進展には金型用鋼の靱性が大きく影響
することを知見した。さらに、ヒートチェックには、主
として高温強度が影響すること、大割れには靱性が影響
することも知見した。However, the inventors of the present invention conducted a crack investigation of the mold, an analysis of thermal stress, a mechanical stress, and a crack propagation test of the mold steel, and as a result, the toughness of the mold steel was found to be large in the crack propagation. It was found that it has a great influence. Furthermore, it was also found that the high-temperature strength mainly affects the heat check, and the toughness affects the large crack.
【００１０】従って、亀裂の進展、ヒートチェック、大
割れに対して優れた金型用鋼を得るためには、靱性と高
温強度に優れていることが必要であることが判明した。Therefore, it has been found that it is necessary to have excellent toughness and high temperature strength in order to obtain a die steel which is excellent in crack development, heat check and large cracks.
【００１１】そこで、本発明者等は金型用鋼の靱性、高
温強度におよぼす合金元素および不純物元素、さらに組
織の影響を調査した結果、次の３つの事実が明らかにな
った。 Ｎｉ、Ｍｏの添加が靱性の向上に有効であり、Ｃ、Ｓ
ｉ、Ｃｒ、Ｖ、Ｐ、Ｓの添加が靱性の低下を招くこと。 マルテンサイト組織が靱性に優れ、ベイナイト、パー
ライト組織は靱性の低下を招くこと。 Ｓｉ、Ｃｒ、Ｍｏ、Ｖの添加が高温強度の向上に有効
であり、さらに、マルテンサイト組織も高温強度の向上
に有効であること。Then, the present inventors investigated the influence of alloying elements and impurity elements, and the structure on the toughness and high temperature strength of the die steel, and as a result, the following three facts were clarified. Addition of Ni and Mo is effective in improving toughness, and C and S
The addition of i, Cr, V, P, and S leads to a decrease in toughness. The martensite structure is excellent in toughness, and the bainite and pearlite structures cause deterioration in toughness. The addition of Si, Cr, Mo and V is effective for improving the high temperature strength, and the martensite structure is also effective for improving the high temperature strength.
【００１２】本発明は、上記した知見に基づいて成され
たものであり、その要旨とするところは、重量％で、
Ｃ：０．２５〜０．４５％、Ｓｉ：０．５０％以下、Ｍ
ｎ：０．２０〜１．０％、Ｐ：０．０１５％以下、Ｓ：
０．００５％以下、Ｎｉ：０．５〜２．０％、Ｃｒ：
２．８〜４．２％、Ｍｏ：１．０〜２．０％、Ｖ：０．
１〜０．５％を含有し、残部はＦｅおよび不可避的不純
物よりなる靱性と高温強度に優れた熱間鍛造金型用鋼で
ある。The present invention was made on the basis of the above-mentioned findings, and the gist of the present invention is, in terms of weight%,
C: 0.25 to 0.45%, Si: 0.50% or less, M
n: 0.20 to 1.0%, P: 0.015% or less, S:
0.005% or less, Ni: 0.5 to 2.0%, Cr:
2.8-4.2%, Mo: 1.0-2.0%, V: 0.
It is a hot forging die steel which contains 1 to 0.5% and the balance is Fe and inevitable impurities and is excellent in toughness and high temperature strength.
【００１３】[0013]
【作用】以下に、本発明における熱間鍛造金型用鋼の成
分組成の限定理由について述べる。 Ｃ：Ｃは鋼の焼入性を向上させるために不可欠の元素で
あるが、その含有量が０．４５％を越えると靱性の低下
を招く。また、含有量が低下すると、焼入性が低下し、
大断面サイズ金型焼入時にベイナイトが析出し、靱性を
低下させることを考慮して本発明はその含有量を０．２
５〜０．４５％とした。The reason for limiting the composition of the hot forging steel according to the present invention will be described below. C: C is an essential element for improving the hardenability of steel, but if its content exceeds 0.45%, toughness is deteriorated. Further, if the content decreases, hardenability decreases,
In consideration of the fact that bainite is precipitated during quenching of a die having a large cross-section size and reduces the toughness, the content of the present invention is 0.2.
It was set to 5 to 0.45%.
【００１４】Ｓｉ：Ｓｉは高温強度の向上、変態点の上
昇に有効な元素であるが、０．５０％を越えると靱性が
著しく低下することを考慮して本発明はその含有量を
０．５０％以下とした。しかし、ＳｉはＰ、Ｓと共に靱
性に及ぼす影響が大きいので、０．３０％以下が望まし
い。Si: Si is an element effective in improving the high temperature strength and increasing the transformation point. However, in the present invention, the content is set to 0. It was set to 50% or less. However, Si has a great influence on toughness together with P and S, so 0.30% or less is desirable.
【００１５】Ｍｎ：Ｍｎは溶鋼の脱酸、焼入性の向上に
有効な元素であるので下限を０．２０％とした。しか
し、１．０％を越えると被切削性が著しく低下すること
を考慮して上限を１．０％とした。Mn: Mn is an element effective in deoxidizing molten steel and improving hardenability, so the lower limit was made 0.20%. However, the upper limit was set to 1.0% considering that the machinability is significantly reduced when the content exceeds 1.0%.
【００１６】Ｐ：Ｐは不純物元素であり、その含有量が
多いと凝固時のミクロ偏析を助長し、ヒートチェックの
発生、靱性の低下を促すことを考慮して本発明はその含
有量を０．０１５％以下とした。しかし、ヒートチェッ
ク、靱性を考慮すると、その含有量は０．０１０％以下
が望ましい。P: P is an impurity element, and if the content thereof is large, microsegregation at the time of solidification is promoted, and in view of promoting the occurrence of heat check and lowering of toughness, the present invention sets its content to 0. It was set to 0.015% or less. However, considering heat check and toughness, the content is preferably 0.010% or less.
【００１７】Ｓ：Ｓは硫化物介在物を形成し、この介在
物が鍛造時に延伸して、鍛造直角方向の靱性を著しく低
下させるので、これを考慮して本発明はその含有量を
０．００５％以下とした。しかし、０．００２％以下が
好ましい。S: S forms sulfide inclusions, and these inclusions are stretched at the time of forging to significantly reduce the toughness in the direction perpendicular to the forging. It was made 005% or less. However, 0.002% or less is preferable.
【００１８】Ｎｉ：Ｎｉは鋼の靱性の向上、焼入性の向
上に有効な元素であるので、下限を０．５％とした。し
かし、その含有量が増加すると焼入時の残留オーステナ
イト量が増加し、被削性を低下させることを考慮して上
限を２．０％とした。Ni: Ni is an element effective in improving the toughness and hardenability of steel, so the lower limit was made 0.5%. However, the upper limit was set to 2.0% in consideration that the amount of retained austenite at the time of quenching increases and the machinability decreases as its content increases.
【００１９】Ｃｒ：Ｃｒは鋼の焼入性の向上、炭化物生
成による耐磨耗性向上、高温強度の向上、窒化硬さの向
上、軟化抵抗の向上など工具鋼には不可欠な元素である
が、その含有量が４．２％を越えると靱性の低下を招
く。一方、２．８％未満では、特に耐磨耗性の低下が顕
著になることを考慮して本発明はその含有量を２．８〜
４．２％とした。Cr: Cr is an indispensable element for tool steels such as improvement of hardenability of steel, improvement of wear resistance due to formation of carbide, improvement of high temperature strength, improvement of nitriding hardness, improvement of softening resistance. If the content exceeds 4.2%, the toughness is lowered. On the other hand, in the case where the content is less than 2.8%, the present invention considers that the wear resistance is particularly lowered, and therefore the content of the present invention is 2.8 to
It was 4.2%.
【００２０】Ｍｏ：ＭｏはＣｒと同様に工具鋼の主要元
素であり、特に鋼の焼入性の向上、高温強度の向上、靱
性の向上に有効な元素であるが、その含有量が２．０％
を越えると靱性の低下を招く。一方、１．０％未満で
は、高温強度の改善に十分な効果を得られないことを考
慮して本発明はその含有量を１．０〜２．０％とした。Mo: Mo, like Cr, is a main element of tool steel and is an element which is particularly effective for improving the hardenability, high temperature strength and toughness of steel, but its content is 2. 0%
If it exceeds, the toughness is lowered. On the other hand, if the content is less than 1.0%, the content is set to 1.0 to 2.0% in the present invention in consideration of the fact that sufficient effect for improving the high temperature strength cannot be obtained.
【００２１】Ｖ：ＶもＣｒ、Ｍｏとともに工具鋼の主要
元素であり、鋼の耐磨耗性向上、高温強度の向上、窒化
硬さの向上、軟化抵抗の向上などに有効な元素である
が、その含有量が０．５％を越えると炭化物偏析により
靱性が大きく低下する。一方、０．１％未満では、高温
強度の改善、結晶粒の微細化に十分な効果を得られない
ことを考慮して本発明はその含有量を０．１〜０．５％
とした。V: V is also a main element of tool steel together with Cr and Mo and is an element effective for improving wear resistance, high temperature strength, nitriding hardness and softening resistance of steel. However, if its content exceeds 0.5%, the segregation of carbides causes a significant decrease in toughness. On the other hand, if the content is less than 0.1%, the content of the present invention is 0.1 to 0.5% in view of the fact that sufficient effects cannot be obtained for improvement of high temperature strength and refinement of crystal grains.
And
【００２２】[0022]
【実施例】次に本発明の一実施例を比較例と対比しなが
ら説明する。なお、これらの実施例は本発明の効果を示
す例示であって、本発明の技術的範囲を何等制限するも
のでないことは勿論である。EXAMPLES Next, one example of the present invention will be described in comparison with a comparative example. It is needless to say that these examples are examples showing the effects of the present invention and do not limit the technical scope of the present invention.
【００２３】表１（本発明鋼）および表２（比較鋼）に
示す化学成分の鋼を溶製、鍛造（鍛練比５）、焼鈍した
後に半仕上加工して大物鍛造品（製品単重約１５ｋｇ）
成形用金型素材を製造した。さらに、これを９００〜１
０２０ OＣに加熱して、油焼入れした後に５７０〜６１
０ OＣの温度で焼戻しを行い、鋼の硬さをＨR Ｃ４５前
後に調整し、金型素材を製造した。本発明鋼はＪＩＳ規
格ＳＫＤ６１と比較してＣｒおよびＶ含有量を低減させ
ているため、炭化物の球状化焼鈍を省略しても靱性が低
下しない。また、焼入温度を９００〜９８０ OＣとＳＫ
Ｄ６１の場合（１０１０〜１０２０ OＣ）より下げるこ
とができる。この金型素材を型彫加工の後に硬質クロム
メッキ処理を施し、熱間鍛造金型として使用した。Steels having chemical compositions shown in Table 1 (inventive steels) and Table 2 (comparative steels) are melted, forged (forging ratio 5), annealed, and then semi-finished to make a large forged product (product weight: approx. 15kg)
A mold material for molding was manufactured. Furthermore, this is 900-1
It was heated to 020 O C, after oil quenching 570-61
Tempering was performed at a temperature of 0 O C to adjust the hardness of the steel to around H R C45, and a die material was manufactured. Since the steels of the present invention have lower Cr and V contents compared to JIS standard SKD61, the toughness does not decrease even if spheroidizing annealing of carbide is omitted. In addition, the quenching temperature 900~980 O C and SK
It can be lowered than that of D61 (1010~1020 O C). This die material was subjected to a hard chrome plating treatment after die-cutting and used as a hot forging die.
【００２４】[0024]
【表１】 [Table 1]
【００２５】[0025]
【表２】 [Table 2]
【００２６】前記金型素材の鍛造方向と直角な方向より
試験片を採取し、高温引張試験、破壊靱性試験、衝撃遷
移温度曲線試験および亀裂進展試験を行った。６００ O
Ｃの温度下での引張試験の０．２％耐力値を高温強度と
した。また、衝撃遷移温度は２ｍｍＵノッチのシャルピ
ー衝撃試験の延性−脆性５０％破面率温度を求めた。さ
らに、前記熱間鍛造金型使用より型打命数および金型寿
命原因を調査した。Test pieces were taken from a direction perpendicular to the forging direction of the die material and subjected to a high temperature tensile test, a fracture toughness test, an impact transition temperature curve test and a crack growth test. 600 O
The 0.2% proof stress value of the tensile test under the temperature of C was defined as the high temperature strength. In addition, the impact transition temperature was determined as the ductility-brittleness 50% fracture surface temperature in a Charpy impact test with a 2 mm U notch. Furthermore, the number of die hits and the cause of die life were investigated by using the hot forging die.
【００２７】これらの鋼のうちのＮｏ．１６〜１８およ
びＮｏ．３６、３７の高温強度測定結果を図１に、破壊
靱性試験結果を図２に、衝撃遷移温度試験結果を図３
に、さらに亀裂進展試験結果を図４に示す。また、熱間
鍛造金型として使用した結果（型打命数および金型寿命
原因）を表３に示す。No. out of these steels 16-18 and No. The high temperature strength measurement results of 36 and 37 are shown in FIG. 1, the fracture toughness test result is shown in FIG. 2, and the impact transition temperature test result is shown in FIG.
Fig. 4 shows the results of the crack growth test. Table 3 shows the results (number of die hits and cause of die life) when used as a hot forging die.
【００２８】[0028]
【表３】 [Table 3]
【００２９】図１より本発明の鋼は、従来の鋼よりも高
温強度が優れていることは明らかである。また、図２よ
り本発明の鋼は、従来の鋼よりも靱性が高いことは明ら
かである。図３より本発明の鋼は、従来の鋼よりも遷移
温度が低いことは明らかである。従来の鋼は金型温度を
１５０〜２００ OＣに維持しないと大割れを起こしやす
いが、本発明の鋼の遷移温度は、ＨＢ５００でも１００
OＣ以下であり、金型温度が低下しても大割れが生じる
懸念はない。図４より本発明の鋼は、応力拡大係数の変
化が大きい領域において、亀裂進展抵抗が高いことを示
している。表３より本発明の鋼は、熱間鍛造金型に使用
時は従来の鋼よりも寿命が長いことは明らかである。即
ち、本発明によると、高温強度と靱性が優れている鋼を
得ることができる。From FIG. 1, it is clear that the steel of the present invention has higher high temperature strength than the conventional steel. Further, it is clear from FIG. 2 that the steel of the present invention has higher toughness than the conventional steel. From FIG. 3, it is clear that the steel of the present invention has a lower transition temperature than the conventional steel. Conventional steel prone to large cracks and does not maintain a mold temperature of 150 to 200 O C, but the transition temperature of the steel of the present invention, even HB500 100
Since it is O C or less, there is no concern that large cracks will occur even if the mold temperature decreases. FIG. 4 shows that the steel of the present invention has high crack growth resistance in a region where the change in stress intensity factor is large. It is clear from Table 3 that the steel of the present invention has a longer life than the conventional steel when used in a hot forging die. That is, according to the present invention, it is possible to obtain steel having excellent high temperature strength and toughness.
【００３０】[0030]
【発明の効果】前記した如く、本発明は高温強度、靱性
に優れた鋼を提供することができ、熱間鍛造金型鋼とし
て使用時には、ヒートチェック、亀裂の進展、大割れに
対して改善されているので、従来よりも寿命の長い金型
を提供することができる。As described above, the present invention can provide a steel excellent in high temperature strength and toughness, and when used as a hot forging die steel, it is improved against heat check, crack development and large crack. Therefore, it is possible to provide a mold having a longer life than conventional ones.
【図１】本実施例のうちのＮｏ．１６〜１８およびＮ
ｏ．３６、３７の高温強度測定結果（６００ OＣ温度条
件下での０．２％耐力測定値）を示す図である。FIG. 1 is a diagram showing the No. of the present embodiment. 16-18 and N
o. It is a figure which shows the high temperature strength measurement result of 36, 37 (0.2% proof stress measurement value under 600 OC temperature conditions).
【図２】本実施例のうちのＮｏ．１６〜１８およびＮ
ｏ．３６、３７の破壊靱性試験結果を示す図である。2 is a diagram showing the No. of the present embodiment. 16-18 and N
o. It is a figure which shows the fracture toughness test result of 36,37.
【図３】本実施例のうちのＮｏ．１６〜１８およびＮ
ｏ．３６、３７の衝撃遷移温度試験結果を示す図であ
る。FIG. 3 is a diagram showing the No. of the present embodiment. 16-18 and N
o. It is a figure which shows the impact transition temperature test result of 36,37.
【図４】本実施例のうちのＮｏ．１６〜１８およびＮ
ｏ．３６、３７の亀裂進展試験結果を示す図である。FIG. 4 is a diagram showing the No. of the present embodiment. 16-18 and N
o. It is a figure which shows the crack growth test result of 36,37.
Claims (1)
Ｓｉ：０．５０％以下、Ｍｎ：０．２０〜１．０％、
Ｐ：０．０１５％以下、Ｓ：０．００５％以下、Ｎｉ：
０．５〜２．０％、Ｃｒ：２．８〜４．２％、Ｍｏ：
１．０〜２．０％、Ｖ：０．１〜０．５％を含有し、残
部はＦｅおよび不可避的不純物よりなる靱性と高温強度
に優れた熱間鍛造金型用鋼。1. C: 0.25 to 0.45% by weight,
Si: 0.50% or less, Mn: 0.20 to 1.0%,
P: 0.015% or less, S: 0.005% or less, Ni:
0.5-2.0%, Cr: 2.8-4.2%, Mo:
Hot forging die steel containing 1.0 to 2.0%, V: 0.1 to 0.5%, and the balance consisting of Fe and inevitable impurities and excellent in toughness and high temperature strength.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6753793A JP2959319B2 (en) | 1993-03-02 | 1993-03-02 | Hot forging die steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6753793A JP2959319B2 (en) | 1993-03-02 | 1993-03-02 | Hot forging die steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06256897A true JPH06256897A (en) | 1994-09-13 |
| JP2959319B2 JP2959319B2 (en) | 1999-10-06 |
Family
ID=13347832
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6753793A Expired - Lifetime JP2959319B2 (en) | 1993-03-02 | 1993-03-02 | Hot forging die steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2959319B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0756018A1 (en) * | 1995-07-26 | 1997-01-29 | National-Oilwell, L.P. | Alloy steel for roll caster shell |
| EP1087030A2 (en) * | 1999-09-22 | 2001-03-28 | Sumitomo Metal Industries, Ltd. | Method of producing tool steel and tool |
| JP2015221933A (en) * | 2014-05-23 | 2015-12-10 | 大同特殊鋼株式会社 | Steel for metal mold and metal mold |
| JP2015224363A (en) * | 2014-05-27 | 2015-12-14 | 大同特殊鋼株式会社 | Steel for metallic mold and metallic mold |
| EP3050649A1 (en) | 2015-01-28 | 2016-08-03 | Daido Steel Co.,Ltd. | Steel powder and mold using the same |
| WO2019028227A1 (en) * | 2017-08-02 | 2019-02-07 | Kennametal Inc. | Tool steel articles from additive manufacturing |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5456913A (en) * | 1977-10-15 | 1979-05-08 | Daido Steel Co Ltd | Steel for hot rolling mold |
| JPS6267152A (en) * | 1985-09-18 | 1987-03-26 | Hitachi Metals Ltd | Tool steel for hot working |
| JPS62161942A (en) * | 1986-01-08 | 1987-07-17 | Hitachi Metals Ltd | Tool steel for hot working |
| JPS62250158A (en) * | 1986-04-24 | 1987-10-31 | Sumitomo Metal Ind Ltd | Steel for hot forging molds |
| JPS63203751A (en) * | 1987-02-17 | 1988-08-23 | Daido Steel Co Ltd | Alloy tool steel |
| JPS6462444A (en) * | 1987-09-02 | 1989-03-08 | Kawasaki Steel Co | Press die steel |
| JPH02138439A (en) * | 1989-10-18 | 1990-05-28 | Daido Steel Co Ltd | Tool steel for tool for forming |
| JPH04318148A (en) * | 1991-04-18 | 1992-11-09 | Hitachi Metals Ltd | Tool steel for hot working |
-
1993
- 1993-03-02 JP JP6753793A patent/JP2959319B2/en not_active Expired - Lifetime
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5456913A (en) * | 1977-10-15 | 1979-05-08 | Daido Steel Co Ltd | Steel for hot rolling mold |
| JPS6267152A (en) * | 1985-09-18 | 1987-03-26 | Hitachi Metals Ltd | Tool steel for hot working |
| JPS62161942A (en) * | 1986-01-08 | 1987-07-17 | Hitachi Metals Ltd | Tool steel for hot working |
| JPS62250158A (en) * | 1986-04-24 | 1987-10-31 | Sumitomo Metal Ind Ltd | Steel for hot forging molds |
| JPS63203751A (en) * | 1987-02-17 | 1988-08-23 | Daido Steel Co Ltd | Alloy tool steel |
| JPS6462444A (en) * | 1987-09-02 | 1989-03-08 | Kawasaki Steel Co | Press die steel |
| JPH02138439A (en) * | 1989-10-18 | 1990-05-28 | Daido Steel Co Ltd | Tool steel for tool for forming |
| JPH04318148A (en) * | 1991-04-18 | 1992-11-09 | Hitachi Metals Ltd | Tool steel for hot working |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0756018A1 (en) * | 1995-07-26 | 1997-01-29 | National-Oilwell, L.P. | Alloy steel for roll caster shell |
| EP1087030A2 (en) * | 1999-09-22 | 2001-03-28 | Sumitomo Metal Industries, Ltd. | Method of producing tool steel and tool |
| US6478898B1 (en) | 1999-09-22 | 2002-11-12 | Sumitomo Metal Industries, Ltd. | Method of producing tool steels |
| EP1087030A3 (en) * | 1999-09-22 | 2003-05-14 | Sumitomo Metal Industries, Ltd. | Method of producing tool steel and tool |
| JP2015221933A (en) * | 2014-05-23 | 2015-12-10 | 大同特殊鋼株式会社 | Steel for metal mold and metal mold |
| JP2015224363A (en) * | 2014-05-27 | 2015-12-14 | 大同特殊鋼株式会社 | Steel for metallic mold and metallic mold |
| EP3050649A1 (en) | 2015-01-28 | 2016-08-03 | Daido Steel Co.,Ltd. | Steel powder and mold using the same |
| US10975460B2 (en) | 2015-01-28 | 2021-04-13 | Daido Steel Co., Ltd. | Steel powder and mold using the same |
| WO2019028227A1 (en) * | 2017-08-02 | 2019-02-07 | Kennametal Inc. | Tool steel articles from additive manufacturing |
| US10889872B2 (en) | 2017-08-02 | 2021-01-12 | Kennametal Inc. | Tool steel articles from additive manufacturing |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2959319B2 (en) | 1999-10-06 |
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