JP2959319B2 - Hot forging die steel - Google Patents
Hot forging die steelInfo
- Publication number
- JP2959319B2 JP2959319B2 JP6753793A JP6753793A JP2959319B2 JP 2959319 B2 JP2959319 B2 JP 2959319B2 JP 6753793 A JP6753793 A JP 6753793A JP 6753793 A JP6753793 A JP 6753793A JP 2959319 B2 JP2959319 B2 JP 2959319B2
- Authority
- JP
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- Prior art keywords
- steel
- toughness
- present
- hot forging
- mold
- 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.)
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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 mold used for a high-load, high-speed hot forging press die or the like.
【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 specified 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 caused by repeated wear of the die opening due to friction between the hot workpiece and the die, rapid heating and rapid cooling on the die surface. This is a crack (heat check) due to thermoplastic strain caused by the crack, a crack progressing due to mechanical stress such as a forming load, and a large crack.
【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。[0004] In order to improve the damage of the mold, improvement of the material of SKT4 or SKD61, improvement of mold material manufacturing technology, and improvement by mold surface treatment such as nitriding have been performed. However, the use conditions of the mold, such as the speeding up of the forging cycle and the complication of the forged product shape, have become severe, and as a result, the mold life has been shortened despite the aforementioned improvements being made. 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。[0005] In addition, due to the speeding up of the forging cycle and the complicated shape of the forged product, the main cause of scrapping the mold has been changed from conventional wear to cracking. In particular, the main cause for crack propagation 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。An object of the present invention is to speed up a forging cycle,
Heat check, crack growth (low cycle fatigue), even under severe mold use conditions such as complicated forged product shapes,
An object of the present invention is to provide an excellent hot forging die steel 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 present inventors have conducted intensive experiments and studies, and as a result, have found that the generation and propagation of cracks in the steel for hot forging die. It has been found that it is effective to satisfy the following conditions to suppress this.
【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。In general, the strength, ductility (tensile fracture drawing), and toughness (fracture toughness) of tool steel affect the crack growth (low cycle fatigue) of hot forging die 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, as a result of the present inventors' investigation of cracks in the mold, analysis of thermal stress and mechanical stress, and a crack growth test of the mold steel, the toughness of the mold steel was found to be small. It was found that it had a significant effect. Furthermore, it was found that the high-temperature strength mainly affected the heat check, and the toughness affected 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, in order to obtain a mold steel excellent in crack propagation, heat check, and large cracks, it has been found that it is necessary to have excellent toughness and high-temperature strength.
【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。The inventors of the present invention have investigated the effects of alloying elements and impurity elements on the toughness and high-temperature strength of mold steel and the structure thereof, and have found the following three facts. Addition of Ni and Mo is effective in improving toughness, and C and S
Addition of i, Cr, V, P, and S causes a decrease in toughness. The martensite structure has excellent toughness, and the bainite and pearlite structures cause toughness to decrease. 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：０．３６〜０．４５％、Ｓｉ：０．５０％以下、Ｍ
ｎ：０．２０〜１．０％、Ｐ：０．０１５％以下、Ｓ：
０．００５％以下、Ｎｉ：０．８５〜２．０％、Ｃｒ：
２．８〜４．２％、Ｍｏ：１．０〜２．０％、Ｖ：０．
１〜０．５％未満を含有し、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 has been made based on the above-mentioned findings, and the gist of the present invention is that the weight%
C: 0. 36 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. 8 5~2.0%, Cr:
2.8-4.2%, Mo: 1.0-2.0%, V: 0.
It is a hot forging die steel containing 1 to less than 0.5%, with the balance being Fe and inevitable impurities and having excellent 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０．３６〜０．４５％とし
た。The reason for limiting the component composition of the steel for hot forging die in the present invention will be described below. C: C is an indispensable element for improving the hardenability of steel, but if its content exceeds 0.45%, the toughness is reduced. In addition, when the content decreases, the hardenability decreases, and bainite precipitates during the quenching of a large-section size die, and the present invention considers that the content is 0. 36 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 for improving the high-temperature strength and increasing the transformation point. However, in consideration of the fact that if it exceeds 0.50%, the toughness is remarkably reduced, the present invention sets the content to 0.1%. 50% or less. However, Si has a large effect on toughness together with P and S, so that 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 for improving the deoxidation and hardenability of molten steel, so the lower limit was made 0.20%. However, the upper limit was set to 1.0% in consideration of the fact that if it exceeds 1.0%, the machinability is significantly reduced.
【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. If the content of P is large, micro segregation during solidification is promoted, the occurrence of heat check and the reduction of toughness are considered. 0.015% or less. However, considering heat check and toughness, the content is desirably 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 elongated during forging, and significantly reduce the toughness in the direction perpendicular to the forging. 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０．８５％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: Since Ni is an element effective for improving the toughness and hardenability of steel, the lower limit is set to 0.1%. It was 8 5%.
However, the upper limit was made 2.0% in consideration of the fact that when the content increases, the amount of retained austenite at the time of quenching increases and the machinability is reduced.
【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 in tool steel, such as improvement in hardenability of steel, improvement in wear resistance due to carbide formation, improvement in high-temperature strength, improvement in nitriding hardness, and improvement in softening resistance. If the content exceeds 4.2%, the toughness is reduced. On the other hand, if the content is less than 2.8%, the present invention considers that the abrasion resistance is remarkably reduced, and the content of the present invention is 2.8 to 2.8%.
It was set to 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: Like Cr, Mo is a main element of tool steel. In particular, Mo is an effective element for improving hardenability, high-temperature strength, and toughness of steel. 0%
If it exceeds, the toughness is reduced. On the other hand, if the content is less than 1.0%, a sufficient effect for improving the high-temperature strength cannot be obtained, and the present invention sets the content to 1.0 to 2.0%.
【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％以上であ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
％未満とした。V: V is also a main element of tool steel together with Cr and Mo, and is an effective element for improving the wear resistance, high-temperature strength, nitriding hardness, and softening resistance of steel. , the content is the toughness is greatly reduced by the carbide segregation and Ru der 0.5% or more. On the other hand, if the content is less than 0.1%, the present invention considers that a sufficient effect of improving the high-temperature strength and refining the crystal grains cannot be obtained, so that the content is set to 0.1 to 0.5.
It was less than%.
【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。Next, an embodiment of the present invention will be described in comparison with a comparative example. It should be noted that these embodiments are exemplifications showing the effects of the present invention, and do not limit the technical scope of the present invention at all.
【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（鍛錬比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℃に加熱して、油焼入れした後に５７０〜６１０
℃の温度で焼戻しを行い、鋼の硬さをＨR Ｃ４５（ＨＢ
４２０）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
℃とＳＫＤ６１の場合（１０１０〜１０２０℃）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。[0023] Table 1 (invention steels) and Table 2 Steels of chemical compositions shown in (comparative steel), forging (forging refining ratio 5), finishing half after annealing processing to big forgings (Product unit weight About 15kg)
A mold material for molding was manufactured. Furthermore, this is 900-1
After heating to 020 ° C. and oil quenching, 570 to 610
Tempering at a temperature of ℃ C, the hardness of the steel HR C45 (HB
420) Adjusting back and forth to produce a mold material. Since the steel of the present invention has reduced Cr and V contents as compared with JIS standard SKD61, the toughness does not decrease even if the spheroidizing annealing of carbide is omitted. Further, the quenching temperature is 900 to 980.
° C and SKD61 (1010 to 1020 ° C). This mold material was subjected to hard chrome plating after engraving, and used as a hot forging mold.
【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℃
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。硬さ、高温強度および破壊靱性値を表
１、表２に併せて示す。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。 Test pieces were taken from a direction perpendicular to the forging direction of the mold 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 ° C
The high-temperature strength was defined as the 0.2% proof stress value of the tensile test at the temperature of. The impact transition temperature was a ductile-brittle 50% fracture surface temperature in a Charpy impact test of 2 mm U notch. Further, the number of die strokes and the cause of die life were investigated by using the hot forging die. Shows hardness, high temperature strength and fracture toughness values
1 and Table 2 together. Also used as hot forging die
Table 3 shows the results (number of die strokes and die life).
You.
【００２７】これらの鋼のうち、Ｎｏ．１７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。 Of these steels, No. 17 and No
FIG. 1 shows the results of the high-temperature strength measurements of Nos. 36 and 37, FIG. 2 shows the results of the fracture toughness test, FIG. 3 shows the results of the impact transition temperature test, and FIG. 4 shows the results of the crack growth test .
【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 is superior in high-temperature strength to the conventional steel. Further, it is apparent from FIG. 2 that the steel of the present invention has higher toughness than the conventional steel. FIG. 3 clearly shows 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
O C or less, the mold temperature does not concern a large crack occurs even decreased. FIG. 4 shows that the steel of the present invention has a high crack growth resistance in a region where the change in the stress intensity factor is large. From Table 3, it is clear that the steel of the present invention has a longer life than a conventional steel when used in a hot forging die. That is, according to the present invention, a steel having excellent high-temperature strength and toughness can be obtained.
【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. When used as a hot forging die steel, it is improved against heat check, crack propagation and large cracks. Therefore, it is possible to provide a mold having a longer life than before.
【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. 16-18 and N
o. 37 is a diagram showing a (0.2% proof stress measurement at 600 O C temperature conditions) temperature strength measurements of.
【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。FIG. 16-18 and N
o. It is a figure which shows the fracture toughness test result of Nos. 36 and 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. 16-18 and N
o. It is a figure which shows the impact transition temperature test result of No. 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. 16-18 and N
o. It is a figure which shows the crack growth test results of Nos. 36 and 37.
フロントページの続き (56)参考文献 特開 昭64−62444（ＪＰ，Ａ) 特開 昭62−161942（ＪＰ，Ａ) 特開 平４−318148（ＪＰ，Ａ) 特開 昭63−203751（ＪＰ，Ａ) 特開 昭54−56913（ＪＰ，Ａ) 特開 平２−138439（ＪＰ，Ａ) 特開 昭62−250158（ＪＰ，Ａ) 特開 昭62−67152（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) C22C 38/00 301 C22C 38/46 Continuation of the front page (56) References JP-A-64-62444 (JP, A) JP-A-62-161942 (JP, A) JP-A-4-318148 (JP, A) JP-A-63-203751 (JP, A) JP-A-54-56913 (JP, A) JP-A-2-138439 (JP, A) JP-A-62-250158 (JP, A) JP-A-62-67152 (JP, A) (58) Field surveyed (Int. Cl. 6 , DB name) C22C 38/00 301 C22C 38/46
Claims (1)
Ｓｉ：０．５０％以下、Ｍｎ：０．２０〜１．０％、
Ｐ：０．０１５％以下、Ｓ：０．００５％以下、Ｎｉ：
０．８５〜２．０％、Ｃｒ：２．８〜４．２％、Ｍｏ：
１．０〜２．０％、Ｖ：０．１〜０．５％未満を含有
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. The method according to claim 1, wherein C: 0.1% by weight. 36 to 0.45%,
Si: 0.50% or less, Mn: 0.20 to 1.0%,
P: 0.015% or less, S: 0.005% or less, Ni:
0. 8 5~2.0%, Cr: 2.8~4.2% , Mo:
A hot forging die steel containing 1.0 to 2.0% and V: less than 0.1 to 0.5%, with the balance being Fe and inevitable impurities, and having excellent 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 JPH06256897A (en) | 1994-09-13 |
| JP2959319B2 true 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) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5599497A (en) * | 1995-07-26 | 1997-02-04 | National-Oilwell, L.P. | Alloy steel roll caster shell |
| US6478898B1 (en) | 1999-09-22 | 2002-11-12 | Sumitomo Metal Industries, Ltd. | Method of producing tool steels |
| JP6647771B2 (en) * | 2014-05-23 | 2020-02-14 | 大同特殊鋼株式会社 | Mold steel and 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 |
| US10975460B2 (en) | 2015-01-28 | 2021-04-13 | Daido Steel Co., Ltd. | Steel powder and mold using the same |
| US10889872B2 (en) | 2017-08-02 | 2021-01-12 | Kennametal Inc. | Tool steel articles from additive manufacturing |
Family Cites Families (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 |
| JPH0765141B2 (en) * | 1985-09-18 | 1995-07-12 | 日立金属株式会社 | 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 die |
| JPH0796696B2 (en) * | 1987-02-17 | 1995-10-18 | 大同特殊鋼株式会社 | 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
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06256897A (en) | 1994-09-13 |
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