EP1048744A1 - Acier pour roulements presentant une excellente resistance au roulement - Google Patents
Acier pour roulements presentant une excellente resistance au roulement Download PDFInfo
- Publication number
- EP1048744A1 EP1048744A1 EP99951124A EP99951124A EP1048744A1 EP 1048744 A1 EP1048744 A1 EP 1048744A1 EP 99951124 A EP99951124 A EP 99951124A EP 99951124 A EP99951124 A EP 99951124A EP 1048744 A1 EP1048744 A1 EP 1048744A1
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- EP
- European Patent Office
- Prior art keywords
- mass
- less
- fatigue life
- rolling contact
- contact fatigue
- 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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Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
Definitions
- the present invention relates to bearing steels which are used as components for rolling bearings, such as roller bearings and ball bearings. More particularly, the invention relates to a bearing steel used as a component for bearings having superior rolling contact fatigue life.
- Bearing steels used for rolling bearings and the like are required to have a long rolling contact fatigue life. It is well known that, in general, hard oxide non-metallic inclusions in the steel adversely affect the rolling contact fatigue life of the bearing.
- Japanese Unexamined Patent Application Publication No. 3-126839 discloses a method of adjusting the number of oxide non-metallic inclusions per unit area or per unit volume, namely, a method of adjusting the distribution thereof.
- Japanese Unexamined Patent Application Publication No. 5-25587 discloses a method of adjusting the predicted maximum diameter of the oxide non-metallic inclusions calculated based on statistics of extreme value , namely, a method of adjusting the shape thereof. In either case, the influence of the oxide non-metallic inclusions is reduced by adjusting the distribution or shape of the oxide non-metallic inclusions, not by adjusting the amount thereof.
- the present invention has been carried out to achieve the object described above. Owing to recent steelmaking techniques, when approximately 1 mass% of C is incorporated, it is possible to reduce the O content to approximately 0.0010 mass% even without adding Si or Al as the deoxidizing agent. The improvement in hardenability and in rolling contact fatigue life can be achieved by the addition of a large amount of Cr instead of by the addition of Si or Al. Accordingly, the present inventors have carried out researches on the influences of impurity elements, using a material which contains approximately 1 mass% of C and a large amount of Cr, and does not contain Si or Al, in which the O content is reduced to approximately 10 ppm. As a result, it has been found that Sb which is mixed into the steel as the impurity element adversely affects the rolling contact fatigue life.
- the rolling contact fatigue life was investigated using a specimen which contains 0.98 to 1.05 mass% of C, 1.65 to 3.45 mass% of Cr, 0.0008 to 0.0012 mass% of O, 0.0001 to 0.0100 mass% of Sb, and the balance being substantially Fe.
- the number of oxide non-metallic inclusions was 100 to 200 pieces/320 mm 2 , and the maximum diameter thereof was 8 to 12 ⁇ m in an observation area of 320 mm 2 .
- FIG. 1 shows the influence of the Sb content in steel on the rolling contact fatigue life. When the Sb content in the steel was decreased to 0.0015 mass% or less, the rolling contact fatigue life improved. At approximately 0.0010 mass%, the improvement effect was saturated. Although the reason for such a phenomenon is not always clear, when the Sb content in steel exceeds a certain limit, excessive Sb is believed to segregate in grain boundaries, thus promoting fatigue cracks propagation and accelerating the occurrence of fracture.
- the present invention has been achieved based on the knowledge described above.
- a bearing steel having superior rolling contact fatigue life contains 0.95 to 1.10 mass% of C, more than 1.60 to 3.50 mass% of Cr, 0.0015 mass% or less of O, 0.0010 mass% or less of Sb, and the balance being Fe and incidental impurities.
- the bearing steel may further contain at least one element selected from the group consisting of 2.5 mass% or less of Si, 2.5 mass% or less of Mn, 2.5 mass% or less of Mo, 3.0 mass% or less of Ni, 1.5 mass% or less of Nb, 1.5 mass% or less of V, 2.0 mass% or less of Cu, and 0.08 mass% or less of Al.
- Carbon is an element that dissolves in the matrix and effectively strengthens martensite. Carbon is incorporated in order to secure strength after quenching and tempering and to improve rolling contact fatigue life. If the carbon content is less than 0.95 mass%, the above effects are not achieved. If the carbon content exceeds 1.10 mass%, giant carbides are formed in the casting process, resulting in a decrease in workability and in rolling contact fatigue life. Therefore, the carbon content is set in the range of 0.95% to 1.10 mass%.
- Chromium stabilizes carbides and makes the carbides remain after quenching, thus being effective in improving wear resistance. Chromium also improves hardenability and improves cold workability by promoting spheroidization of structure. If the chromium content is 1.60 mass% or less, the above effects are not achieved. If the chromium content exceeds 3.50 mass%, the amount of carbides remaining due to quenching increases. As a result, the amount of carbon dissolved in the matrix is decreased, resulting in a decrease in strength and in rolling contact fatigue life. Therefore, the chromium content is set in the range of more than 1.60% to 3.50 mass%, and preferably, in the range of more than 1.60 to 2.50 mass%.
- the oxygen content is set in the range of 0.0015 mass% or less, and preferably, at 0.0010 mass% or less. Sb: 0.0010 mass% or less
- Antimony is a particularly important element in the present invention. Antimony suppresses the formation of a decarburized layer and improves the productivity in heat treatment, which is advantageous. However, antimony decreases hot workability and toughness and significantly decreases rolling contact fatigue life. Therefore, the antimony content must be limited to 0.0010 mass% or less.
- Silicon is an element that retards softening during tempering. Consequently, strength after quenching and tempering is increased and rolling contact fatigue life is improved. Silicon is an element that also acts as a deoxidizing agent in the melting process to reduce oxygen in the steel. However, if the amount of silicon added exceeds 2.5 mass%, workability and toughness are decreased. Therefore, the silicon content is set in the range of 2.5 mass% or less, and preferably, in the range of 0.15% to 2.0 mass%.
- Manganese is an element that improves the hardenability of steel. Consequently, manganese improves the toughness and strength of matrix martensite and improves rolling contact fatigue life. However, if the manganese content exceeds 2.5 mass%, machinability and toughness are decreased. Therefore, the manganese content is set in the range of 2.5 mass% or less, and preferably, in the range of 0.10 to 2.0 mass%.
- Molybdenum is an element that improves hardenability. Consequently, molybdenum improves strength as well as rolling contact fatigue life. However, if the amount of molybdenum added exceeds 2.5 mass%, carbides are stabilized. As a result, the strength is decreased and the rolling contact fatigue life is decreased. Molybdenum is also an expensive element. Therefore, the molybdenum content is set in the range of 2.5 mass% or less, and preferably, in the range of 0.10 to 1.5 mass%.
- Nickel is an element that improves hardenability. Consequently, nickel improves strength as well as rolling contact fatigue life. However, the effects of addition in the amount exceeding 3.0 mass% are saturated. Nickel is also an expensive element. Therefore, in view of the effect gained and cost, the nickel content is set in the range of 3.0 mass% or less, and preferably, in the range of 0.10 to 2.0 mass%.
- Niobium is an element that improves hardenability. Consequently, niobium improves strength as well as rolling contact fatigue life. However, if the amount of niobium added exceeds 1.5 mass%, carbides are stabilized. As a result, the strength is decreased and the rolling contact fatigue life is decreased. Niobium is also an expensive element. Therefore, the niobium content is set in the range of 1.5 mass% or less, and preferably, in the range of 0.05 to 1.0 mass%.
- Vanadium is an element that improves hardenability. Consequently, vanadium improves strength as well as rolling contact fatigue life. However, if the amount of vanadium added exceeds 1.5 mass%, carbides are stabilized. As a result, the strength is decreased and the rolling contact fatigue life is decreased. Vanadium is also an expensive element. Therefore, the vanadium content is set at 1.5 mass%or less, and preferably, in the range of 0.05% to 1.0mass%.
- Aluminum is an element that increases resistance to temper softening. Consequently, strength after quenching and tempering is increased and rolling contact fatigue life is improved. Aluminum is an element that also acts as a deoxidizing agent in the melting process to reduce oxygen in the steel. If the amount of silicon added exceeds 0.08 mass%, workability and toughness are decreased. Therefore, the aluminum content is set in the range of 0.08 mass% or less, and preferably, in the range of 0.005 to 0.05 mass%.
- phosphorus, sulfur, titanium, and nitrogen, as impurity elements are desirably restricted within the ranges described below.
- Phosphorus decreases the toughness and rolling contact fatigue life of the steel. Therefore, it is desirable that the phosphorus content be as low as possible.
- the permissible upper limit of the phosphorus content is set at 0.025 mass%, and preferably, at 0.015 mass%.
- Sulfur combines with manganese to form MnS and improves machinability. However, rolling contact fatigue life is decreased when a large amount of sulfur is incorporated.
- the permissible upper limit of the sulfur content is set at 0.025 mass%, and preferably, at 0.010 mass%.
- Titanium forms hard nitrides and decreases rolling contact fatigue life. Therefore, it is desirable that the titanium content be as low as possible.
- the permissible upper limit of the titanium content is set at 0.010 mass%, and preferably, at 0.005 mass%.
- Nitrogen forms hard nitrides and decreases rolling contact fatigue life. Therefore, it is desirable that the nitrogen content be as low as possible.
- the permissible upper limit of the nitrogen content is set at 0.015 mass%, and preferably, at 0.008 mass%.
- Each of the steels having the chemical composition shown in Tables 1 and 2 were melted in a converter, and then a bloom having a size of 400 ⁇ 560 mm was produced by continuous casting.
- the bloom was subjected to soaking at 1,200°C for 30 hours, and hot rolled to a steel bar with a diameter of 65 mm.
- the steel bar was subjected to normalizing at 860°C and spheroidizing annealing in the range of 760 to 800°C, and was maintained at 830°C for 30 minutes, followed by quenching, and then tempering was performed at 180°C for 2 hours.
- the tempered material was cut and lapped, and 12 specimens for a rolling contact fatigue test, which were shaped like a disk having a size of 60 mm in diameter by 5 mm thick, were obtained for each steel.
- the rolling contact fatigue test was performed with a Mori thrust-type rolling contact fatigue tester under operating conditions of a maximum Hertzian contact stress of 5,260 MPa and a stress cycle frequency of 30 Hz, using #68 turbine oil as a lubricant oil.
- the test results were plotted onto a probability paper in accordance with a Weibull distribution, and the B 10 life (the total number of load cycles which were repeatedly applied until flaking occurred at an accumulated failure probability of 10%) was obtained. Evaluation was performed based on the relative ratio to the life of Steel No. 1 (JIS steel type: SUJ2) as a conventional steel being set as 1.
- a bearing steel having significantly superior rolling contact fatigue life can be obtained by merely adjusting the composition, such as by adding a large amount of Cr, and in particular, by limiting the Sb content in the steel to 0.0010 mass% or less.
- the Sb content can be easily limited by controlling scraps, which is advantageous in view of productivity, and industrial contributions are great.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Rolling Contact Bearings (AREA)
- Paper (AREA)
- Heat Treatment Of Articles (AREA)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP31879598A JP3779078B2 (ja) | 1998-11-10 | 1998-11-10 | 転動疲労寿命に優れる軸受用鋼 |
JP31879598 | 1998-11-10 | ||
PCT/JP1999/005986 WO2000028100A1 (fr) | 1998-11-10 | 1999-10-28 | Acier pour roulements presentant une excellente resistance au roulement |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1048744A1 true EP1048744A1 (fr) | 2000-11-02 |
EP1048744A4 EP1048744A4 (fr) | 2001-02-28 |
Family
ID=18103038
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP99951124A Withdrawn EP1048744A4 (fr) | 1998-11-10 | 1999-10-28 | Acier pour roulements presentant une excellente resistance au roulement |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP1048744A4 (fr) |
JP (1) | JP3779078B2 (fr) |
KR (1) | KR100508463B1 (fr) |
CA (1) | CA2317658A1 (fr) |
TW (1) | TW454042B (fr) |
WO (1) | WO2000028100A1 (fr) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1354971A1 (fr) * | 2001-01-26 | 2003-10-22 | Kawasaki Steel Corporation | Materiau antifriction |
EP1614761A1 (fr) * | 2003-04-16 | 2006-01-11 | JFE Steel Corporation | Matiere en acier possedant une excellente longevite a la fatigue due au roulement et son procede de production |
CN102399533A (zh) * | 2011-09-26 | 2012-04-04 | 宁国市东方碾磨材料有限责任公司 | 耐磨耐腐蚀纳米研磨材料及其制备方法 |
EP2794175A4 (fr) * | 2011-12-20 | 2015-11-11 | Skf Ab | Procédé, anneau & palier |
US9593389B2 (en) | 2007-12-20 | 2017-03-14 | Posco | Steel wire rod for bearing steel, manufacturing method of steel wire rod for bearing steel, heat treatment method of steel bearing, steel bearing and soaking method of bearing steel |
CN108559913A (zh) * | 2018-05-16 | 2018-09-21 | 浙江健力股份有限公司 | 一种GCr15轴承钢管及其制备工艺 |
CN112111696A (zh) * | 2020-09-29 | 2020-12-22 | 钢铁研究总院 | 高等向性和长接触疲劳寿命的高碳轴承钢及制造方法 |
US11788579B2 (en) | 2020-02-17 | 2023-10-17 | Nsk Ltd. | Rolling bearing and method for producing same |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4586313B2 (ja) * | 2001-07-31 | 2010-11-24 | Jfeスチール株式会社 | 二次加工性に優れた高炭素継目無鋼管の製造方法 |
JP5857433B2 (ja) * | 2011-04-14 | 2016-02-10 | 日本精工株式会社 | 転がり案内装置の製造方法 |
JP5810867B2 (ja) * | 2011-11-25 | 2015-11-11 | 新日鐵住金株式会社 | 軸受鋼 |
JP2015510452A (ja) * | 2011-12-20 | 2015-04-09 | アクティエボラゲット・エスコーエッフ | フラッシュバット溶接によって鋼構成要素を製造する方法、および本方法を用いて作成された構成要素 |
JP6056647B2 (ja) * | 2012-06-28 | 2017-01-11 | Jfeスチール株式会社 | 軸受鋼の製造方法およびその製造方法で得られる軸受鋼 |
CN103045957B (zh) * | 2013-01-06 | 2015-07-22 | 奉化市金燕钢球有限公司 | 一种高碳铬不锈轴承钢 |
CN104087866B (zh) * | 2014-07-31 | 2016-04-06 | 宁国市宁武耐磨材料有限公司 | 一种球磨机用高耐热耐磨球 |
CN104109794B (zh) * | 2014-08-01 | 2016-06-01 | 宁国市宁武耐磨材料有限公司 | 一种中铬多元合金耐磨球 |
CN105296838A (zh) * | 2015-10-22 | 2016-02-03 | 宁国市南方耐磨材料有限公司 | 一种高硬高韧耐磨球 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH0649589A (ja) * | 1992-07-29 | 1994-02-22 | Nkk Corp | 冷間成形用軸受鋼 |
JPH06287704A (ja) * | 1993-03-30 | 1994-10-11 | Kawasaki Steel Corp | 繰り返し応力負荷によるミクロ組織変化の遅延特性と熱処理生産性とに優れた軸受鋼 |
JPH06287691A (ja) * | 1993-03-30 | 1994-10-11 | Kawasaki Steel Corp | 熱処理生産性ならびに繰り返し応力負荷によるミクロ組織変化の遅延特性に優れた軸受鋼 |
JPH0711386A (ja) * | 1993-06-25 | 1995-01-13 | Nkk Corp | 冷間成形用軸受鋼 |
JPH07316728A (ja) * | 1994-05-27 | 1995-12-05 | Kawasaki Steel Corp | 熱処理生産性ならびに繰り返し応力負荷によるミクロ組織変化の遅延特性に優れた軸受部材 |
EP0825270A1 (fr) * | 1996-02-29 | 1998-02-25 | Kawasaki Steel Corporation | Materiau de roulements |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH06271982A (ja) * | 1993-03-23 | 1994-09-27 | Kawasaki Steel Corp | 繰り返し応力負荷によるミクロ組織変化の遅延特性に優れた軸受鋼 |
JP3233725B2 (ja) * | 1993-03-30 | 2001-11-26 | 川崎製鉄株式会社 | 繰り返し応力負荷によるミクロ組織変化の遅延特性に優れた軸受鋼 |
JPH0892689A (ja) * | 1994-09-21 | 1996-04-09 | Kawasaki Steel Corp | 繰り返し応力負荷によるミクロ組織変化の遅延特性に優れた軸受用鋼 |
JP3308836B2 (ja) * | 1996-12-06 | 2002-07-29 | 川崎製鉄株式会社 | 軸受用鋼 |
-
1998
- 1998-11-10 JP JP31879598A patent/JP3779078B2/ja not_active Expired - Lifetime
-
1999
- 1999-10-28 KR KR10-2000-7007005A patent/KR100508463B1/ko active IP Right Grant
- 1999-10-28 WO PCT/JP1999/005986 patent/WO2000028100A1/fr active IP Right Grant
- 1999-10-28 EP EP99951124A patent/EP1048744A4/fr not_active Withdrawn
- 1999-10-28 CA CA002317658A patent/CA2317658A1/fr not_active Abandoned
- 1999-11-02 TW TW088119071A patent/TW454042B/zh not_active IP Right Cessation
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH0649589A (ja) * | 1992-07-29 | 1994-02-22 | Nkk Corp | 冷間成形用軸受鋼 |
JPH06287704A (ja) * | 1993-03-30 | 1994-10-11 | Kawasaki Steel Corp | 繰り返し応力負荷によるミクロ組織変化の遅延特性と熱処理生産性とに優れた軸受鋼 |
JPH06287691A (ja) * | 1993-03-30 | 1994-10-11 | Kawasaki Steel Corp | 熱処理生産性ならびに繰り返し応力負荷によるミクロ組織変化の遅延特性に優れた軸受鋼 |
JPH0711386A (ja) * | 1993-06-25 | 1995-01-13 | Nkk Corp | 冷間成形用軸受鋼 |
JPH07316728A (ja) * | 1994-05-27 | 1995-12-05 | Kawasaki Steel Corp | 熱処理生産性ならびに繰り返し応力負荷によるミクロ組織変化の遅延特性に優れた軸受部材 |
EP0825270A1 (fr) * | 1996-02-29 | 1998-02-25 | Kawasaki Steel Corporation | Materiau de roulements |
Non-Patent Citations (7)
Title |
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"ASM Speciality Handbook, Carbon and Alloy Steels." 1996 , ASM INTERNATIONAL , ASM, MATERIALS PARK, OH 44073-0002, OHIO, USA XP002155310 ISBN: 0-87170-557-5 *pages 575-577 and 585* * table 2 * * |
PATENT ABSTRACTS OF JAPAN vol. 018, no. 285 (C-1206), 31 May 1994 (1994-05-31) & JP 06 049589 A (NKK CORP), 22 February 1994 (1994-02-22) * |
PATENT ABSTRACTS OF JAPAN vol. 1995, no. 01, 28 February 1995 (1995-02-28) & JP 06 287691 A (KAWASAKI STEEL CORP), 11 October 1994 (1994-10-11) * |
PATENT ABSTRACTS OF JAPAN vol. 1995, no. 01, 28 February 1995 (1995-02-28) & JP 06 287704 A (KAWASAKI STEEL CORP), 11 October 1994 (1994-10-11) * |
PATENT ABSTRACTS OF JAPAN vol. 1995, no. 04, 31 May 1995 (1995-05-31) & JP 07 011386 A (NKK CORP), 13 January 1995 (1995-01-13) * |
PATENT ABSTRACTS OF JAPAN vol. 1996, no. 04, 30 April 1996 (1996-04-30) & JP 07 316728 A (KAWASAKI STEEL CORP), 5 December 1995 (1995-12-05) * |
See also references of WO0028100A1 * |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1354971A1 (fr) * | 2001-01-26 | 2003-10-22 | Kawasaki Steel Corporation | Materiau antifriction |
EP1354971A4 (fr) * | 2001-01-26 | 2006-01-04 | Jfe Steel Corp | Materiau antifriction |
EP1614761A1 (fr) * | 2003-04-16 | 2006-01-11 | JFE Steel Corporation | Matiere en acier possedant une excellente longevite a la fatigue due au roulement et son procede de production |
EP1614761A4 (fr) * | 2003-04-16 | 2007-02-28 | Jfe Steel Corp | Matiere en acier possedant une excellente longevite a la fatigue due au roulement et son procede de production |
US7763124B2 (en) | 2003-04-16 | 2010-07-27 | Jfe Steel Corporation | Steel material with excellent rolling fatigue life and method of producing the same |
US9593389B2 (en) | 2007-12-20 | 2017-03-14 | Posco | Steel wire rod for bearing steel, manufacturing method of steel wire rod for bearing steel, heat treatment method of steel bearing, steel bearing and soaking method of bearing steel |
CN102399533A (zh) * | 2011-09-26 | 2012-04-04 | 宁国市东方碾磨材料有限责任公司 | 耐磨耐腐蚀纳米研磨材料及其制备方法 |
EP2794175A4 (fr) * | 2011-12-20 | 2015-11-11 | Skf Ab | Procédé, anneau & palier |
CN108559913A (zh) * | 2018-05-16 | 2018-09-21 | 浙江健力股份有限公司 | 一种GCr15轴承钢管及其制备工艺 |
US11788579B2 (en) | 2020-02-17 | 2023-10-17 | Nsk Ltd. | Rolling bearing and method for producing same |
CN112111696A (zh) * | 2020-09-29 | 2020-12-22 | 钢铁研究总院 | 高等向性和长接触疲劳寿命的高碳轴承钢及制造方法 |
Also Published As
Publication number | Publication date |
---|---|
TW454042B (en) | 2001-09-11 |
EP1048744A4 (fr) | 2001-02-28 |
KR100508463B1 (ko) | 2005-08-17 |
WO2000028100A1 (fr) | 2000-05-18 |
JP2000144326A (ja) | 2000-05-26 |
CA2317658A1 (fr) | 2000-05-18 |
KR20010033504A (ko) | 2001-04-25 |
JP3779078B2 (ja) | 2006-05-24 |
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