WO2016035519A1 - 非調質型軟窒化部品 - Google Patents
非調質型軟窒化部品 Download PDFInfo
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- WO2016035519A1 WO2016035519A1 PCT/JP2015/072707 JP2015072707W WO2016035519A1 WO 2016035519 A1 WO2016035519 A1 WO 2016035519A1 JP 2015072707 W JP2015072707 W JP 2015072707W WO 2016035519 A1 WO2016035519 A1 WO 2016035519A1
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- 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
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/06—Surface hardening
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/28—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for plain shafts
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- 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
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- 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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- 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
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- 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
- C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
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- 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
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
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- 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
- C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
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- 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
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
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- 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
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
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- 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
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
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- 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
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
- C23C8/28—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases more than one element being applied in one step
- C23C8/30—Carbo-nitriding
- C23C8/32—Carbo-nitriding of ferrous surfaces
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/80—After-treatment
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C3/00—Shafts; Axles; Cranks; Eccentrics
- F16C3/04—Crankshafts, eccentric-shafts; Cranks, eccentrics
- F16C3/06—Crankshafts
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/002—Bainite
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/30—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for crankshafts; for camshafts
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2204/00—Metallic materials; Alloys
- F16C2204/60—Ferrous alloys, e.g. steel alloys
- F16C2204/74—Ferrous alloys, e.g. steel alloys with manganese as the next major constituent
Definitions
- the present invention relates to a non-tempered soft nitriding component. More specifically, the present invention relates to a non-tempered nitrocarburized part having high bending fatigue strength and excellent bending straightening properties.
- Non-tempered nitrocarburized part refers to a part that has been subjected to nitrocarburizing treatment without being subjected to “quenching-tempering treatment” which is a so-called “tempering treatment” after machining.
- quenching-tempering treatment which is a so-called “tempering treatment” after machining.
- soft-nitrided part the above-mentioned “part subjected to soft nitriding” is simply referred to as “soft-nitrided part”.
- Crankshafts and connecting rods used in automobiles, industrial machinery, and construction machinery are manufactured by forging and machining to the required shape and then performing nitrocarburizing treatment without tempering quenching and tempering. Is done.
- a process such as induction hardening or soft nitriding, which is a surface hardening process, is often performed after forging and machining.
- the above “soft nitriding” is intended to diffusion coating of nitrogen and carbon at a temperature below the A 1 transformation point, the heat treatment temperature is low, a large, wherein the heat treatment distortion compared to "induction hardening process” is small It is said.
- a “compound layer” (a layer in which a nitride such as Fe 3 N is deposited) that is observed white when corroded with nital is formed.
- a “diffusion layer” is formed between the compound layer and the dough (hereinafter also referred to as “base material”).
- soft nitrided parts such as crankshafts are required not only to have high bending fatigue strength, but also to have no cracks even when subjected to bending correction, that is, excellent bending correction. .
- the above-mentioned soft nitriding component may be represented by “crankshaft”.
- crankshaft which is the main part of the engine, has been designed to be lightweight and downsized without exception.
- extremely high bending fatigue strength of 800 MPa or more has been demanded. Yes.
- the hardness at the position of 0.05 mm from the part surface (hereinafter sometimes referred to as “surface layer hardness”) is soft nitrided. It is necessary to set the Vickers hardness (hereinafter referred to as “HV hardness”) to 410 or more after the treatment.
- crankshaft rope is required to bend and correct even for a crankshaft having a shape that is more likely to bend than before when soft nitriding, that is, high bend correction.
- Patent Document 1 describes, in mass%, C: 0.2 to 0.6%, Si: 0.05 to 1.0%, Mn : 0.25 to 1.0%, S: 0.03 to 0.2%, Cr: 0.2% or less, s-Al: 0.045% or less, Ti: 0.002 to 0.010%, N: 0.005 to 0.025% and O: 0.001 to 0.005%, and if necessary, Pb: 0.01 to 0.40%, Ca: 0.0005 to 0.005%.
- 0050% and Bi contain one or more of 0.005 to 0.40%, and 0.12 ⁇ Ti% ⁇ O% ⁇ 2.5 ⁇ Ti% and 0.04 ⁇ N% ⁇ O% ⁇ 0.7 ⁇ N% of the conditions are satisfied, the balance is made of Fe and inevitable impurities, and the structure after hot forging is ferrite and Light is a mixed microstructure of "soft-nitriding for non-heat treated steel" is disclosed.
- Patent Document 2 discloses a crankshaft having a pin portion and a journal portion, which is made of steel having a surface subjected to nitriding treatment or soft nitriding treatment.
- the steel has, as alloy components, C: 0.07% by mass to 0.12% by mass, Si: 0.05% by mass to 0.25% by mass, Mn: 0.1% by mass to 0.5% by mass %: Cu: 0.8% to 1.5% by mass, Ni: 2.4% to 4.5% by mass, Al: 0.8% to 1.5% by mass, Ti: 0.5% by mass or more and 1.5% by mass or less, and if necessary, S: 0.01% by mass to 0.10% by mass, Ca: 0.0010% by mass to 0.0050% by mass One or two of them are contained, and the balance consists of Fe and inevitable impurities.
- C 0.07% by mass to 0.12% by mass
- Si 0.05% by mass to 0.25% by mass
- Mn 0.1% by mass to 0.5% by mass %: Cu: 0.8% to 1.5% by mass
- Al 0.8% to 1.5% by mass
- Ti 0.5% by mass or more and 1.5% by mass or less
- S 0.01% by mass to 0.10% by mass
- the ratio of bainite in the steel structure can be 80% or more, and the HV hardness can be 200 or more and 300 or less.
- the internal hardness of the pin portion and the journal portion subjected to nitriding treatment or soft nitriding treatment is 350 to 500 in terms of HV hardness, and HV hardness in the position of 0.05 mm from the surface is 650 to 950 inclusive. It is.
- Patent Document 3 the inventors of the present invention have a mass of steel material of C: 0.25 to 0.60%, Si: 0.10 to 1.0%. , Mn: 0.60 to 2.0%, P: 0.08% or less, S: 0.10% or less, Al: 0.05% or less, Cr: 0.20 to 1.0% and N: 0
- a “non-tempered nitrided crankshaft” is proposed in which the HV hardness is 380 to 600 and the compound layer depth of at least the pin fillet portion, journal fillet portion and pin portion is 5 ⁇ m or less.
- This non-tempered nitrided crankshaft may further contain one or more selected from Cu, Ni, Mo, V, Ti and Ca. In that case, [40 ⁇ C + 2Mn + 5.5Cr + 26Mo ⁇ 43.0] It is necessary to satisfy.
- Patent Document 4 Japanese Patent Application Laid-Open No. 2011-42846
- the steel material of the material is C: 0.25 to 0.40%, Si: 0.10 to 0.00. 35%, Mn: 0.60 to 1.0%, P: 0.08% or less, S: 0.10% or less, Al: 0.05% or less, Cr: 0.30 to 1.10%, and N : A tempered soft nitriding part containing 0.0030 to 0.0250%, the balance being Fe and impurities, the HV hardness at a position of 0.05 mm from the surface is 400 to 600, and the stress concentration Proposed tempered nitrocarburized parts with a compound layer depth of 5 ⁇ m or less.
- the tempered nitrided part may further contain one or more selected from Cu, Mo, V, Ni and Ti.
- JP 2002-226939 A JP 2007-177309 A JP 2012-2605 A JP 2011-42846 A
- the tempered soft nitriding component disclosed in Patent Document 4 is excellent in bending straightening after soft nitriding, and has a high bending fatigue strength of 800 MPa or more in a bending fatigue test. For this reason, it can be used as a part such as an automobile, an industrial machine, and a construction machine, for example, a crankshaft, and it is possible to cope with a reduction in weight and size.
- it is necessary to perform a tempering treatment of quenching and tempering after machining and before soft nitriding.
- the present invention has been made to solve the above problems, and provides a non-tempered nitrocarburized part having excellent bending straightness and high bending fatigue strength of 800 MPa or more in a bending fatigue test. For the purpose.
- the fracture surface of the test piece from which the compound layer was not removed is a starting point of cracking due to the brittle fracture of the compound layer, In the case of the test piece from which the compound layer is removed, it becomes a ductile fracture surface.
- the hardness at the 0.05 mm position from the component surface is HV hardness of 410 or more, and the hardness at the 1.0 mm position from the component surface (hereinafter “internal hardness”). If the HV hardness is 200 or more and the metal structure of the fabric (hereinafter also referred to as “base material structure”) is a bainite structure, a high bending fatigue strength of 800 MPa or more is stable. Can be obtained.
- Non-tempered parts have a lower base material durability ratio (fatigue strength / tensile strength) than tempered parts. Therefore, even if the non-tempered part has the same internal hardness as the tempered part, the fatigue strength of the base material is lower than that of the tempered part.
- the internal hardness of the non-tempered soft nitriding component is as low as less than 200 in HV hardness
- the base material structure is mainly a mixed structure of ferrite and pearlite (hereinafter referred to as “ferrite / pearlite structure”). Even if it has a surface hardness as high as 410 or higher in terms of HV hardness, fracture may occur starting from the inside during a fatigue test, and it may be difficult to obtain a high fatigue strength of 800 MPa or higher.
- the present invention has been completed based on the above findings, and the gist of the present invention is the non-tempered soft nitriding component shown below.
- the chemical composition of the steel material of the fabric is mass%, C: 0.35 to 0.50%, Si: 0.10 to 0.35%, Mn: 2.3 to 2.8% S: 0.10% or less, N: 0.0030 to 0.0250%, Cu: 0 to 1.0%, Mo: 0 to 0.3%, Ni: 0 to 0.5%, Ti: 0 to 0.020%, Balance: Fe and impurities, Fn1 represented by the following formula [1] is 3.10 ⁇ Fn1 ⁇ 6.00, P, Al, and Cr in the impurities are respectively P: 0.08% or less, Al: 0.05% or less, and Cr: less than 0.20%, In the stress concentration part, HV hardness at a position of 0.05 mm from the surface is 410 to 480, The HV hardness at a position of 1.0 mm from the surface is 200 or more, The compound layer depth is 5 ⁇ m or less, and the metal structure of the dough is a bainite structure.
- the chemical composition of the steel material of the dough is mass%, Cu: 0.05 to 1.0% and Mo: 0.05 to 0.3%
- the chemical composition of the steel material of the dough is mass%, Ni: 0.05-0.5% and Ti: 0.005-0.020%
- Impurity refers to what is mixed from ore, scrap, or the production environment as raw materials when industrially producing steel materials.
- Stress concentrated part refers to a part where a crack occurs when fatigue fracture due to bending and bending correction are performed.
- the “stress concentration part” refers to a “pin fillet part” or “journal fillet part”.
- the non-tempered soft nitriding component of the present invention is excellent in bend straightening after soft nitriding treatment, and has a high bending fatigue strength of 800 MPa or more in a bending fatigue test, so that it is a component for automobiles, industrial machinery, construction machinery and the like.
- it can be used as a crankshaft, and it is possible to reduce the weight and size of these components.
- C 0.35-0.50%
- C has the effect of increasing the internal hardness and increasing the bending fatigue strength.
- it is necessary to contain 0.35% or more of C.
- the C content is set to 0.35 to 0.50%.
- the C content is preferably 0.38% or more, and more preferably 0.45% or less.
- Si 0.10 to 0.35%
- Si is an element necessary for deoxidation at the time of melting, and in order to obtain such an effect, the content needs to be at least 0.10%.
- the Si content is set to 0.10 to 0.35%.
- the Si content is preferably 0.15% or more, and preferably 0.30% or less.
- Mn 2.3 to 2.8%
- Mn is an element having a deoxidizing action like Si.
- Mn has the effect of increasing the bending fatigue strength by increasing the amount of dissolved nitrogen in the surface layer during soft nitriding and improving the surface layer hardness. In order to exhibit such an effect, it is necessary to contain 2.3% or more of Mn.
- the Mn content is set to 2.3 to 2.8%.
- the Mn content is preferably 2.4% or more, and preferably 2.7% or less.
- S 0.10% or less S, if contained positively, has an effect of improving machinability. However, when the content of S exceeds 0.10%, the bending fatigue strength and the bending straightness are significantly reduced. Therefore, the content of S is set to 0.10% or less.
- the S content is preferably 0.08% or less. In order to obtain the machinability improving effect, the S content is preferably 0.04% or more.
- N 0.0030 to 0.0250%
- N is an element that improves the bending fatigue strength and the bending straightness. In order to acquire such an effect, it is necessary to contain 0.0030% or more of N. On the other hand, the effect is saturated even if it contains N exceeding 0.0250%. Therefore, the N content is set to 0.0030 to 0.0250%.
- the N content is preferably 0.0080% or more, and is preferably 0.0220% or less.
- Cu 0 to 1.0%
- Cu is an element that increases internal hardness and improves bending fatigue strength. Therefore, you may contain Cu as needed. However, when the Cu content exceeds 1.0%, the hot workability is lowered. Therefore, the amount of Cu in the case of inclusion is set to 1.0% or less.
- the amount of Cu is preferably 0.4% or less, and more preferably 0.3% or less.
- the amount of Cu is preferably 0.05% or more, and more preferably 0.1% or more.
- Mo 0 to 0.3% Mo has the effect
- the amount of Mo is preferably 0.05% or more, and more preferably 0.1% or more.
- the above Cu and Mo can be contained in only one of them or in combination of two.
- the total amount when combined and contained may be 1.3%, but is preferably 0.3% or less.
- Ni 0 to 0.5%
- Ni is an element that increases toughness and improves bend straightening. Therefore, Ni may be included as necessary. However, even if Ni is contained in an amount exceeding 0.5%, the above effect is saturated and the economic efficiency is impaired. Therefore, the amount of Ni in the case of inclusion is set to 0.5% or less.
- the amount of Ni is preferably 0.3% or less, and more preferably 0.2% or less.
- the amount of Ni is preferably 0.05% or more, and more preferably 0.08% or more.
- Ni is combined so that Ni / Cu ⁇ 0.5 is satisfied. Is preferably contained.
- Ti 0 to 0.020%
- Ti is an element that improves bend straightening by forming nitrides, making crystal grains fine, and making cracks difficult to progress during bending straightening. Therefore, you may contain Ti as needed. However, when the Ti content exceeds 0.020%, the nitride becomes coarse, and conversely, even if the compound layer depth of the stress concentration portion is 5 ⁇ m or less, the bending straightness is remarkably lowered. Therefore, when Ti is included, the amount of Ti is set to 0.020% or less. The amount of Ti is preferably 0.015% or less.
- the amount of Ti is preferably 0.005% or more.
- said Ni and Ti can be contained only in one of them, or 2 types of composites.
- the total amount when combined and contained may be 0.520%, but is preferably 0.30% or less.
- Fn1 Within the range of 3.10 to 6.00
- Fn1 is an index related to the base material structure. C, Si, Mn, Ni, Cr and Mo all improve the hardenability of the steel. If Fn1 is 3.10 or more, the hardenability of the steel material becomes sufficiently high, and the base material structure becomes a bainite structure, whereby a high durability ratio can be imparted to the base material. However, if it exceeds 6.00, the base material structure becomes a martensite structure, the hardness becomes excessively high, and the bending straightness is adversely affected. Therefore, 3.10 ⁇ Fn1 ⁇ 6.00. Fn1 is preferably 3.50 or more, and preferably 5.00 or less.
- the chemical composition of the base steel material is such that the above elements and the balance are Fe and impurities, and P, Al, and Cr in the impurities are P: 0.08%, respectively.
- P, Al, and Cr in the impurities are P: 0.08%, respectively.
- Al 0.05% or less
- Cr less than 0.20%.
- P 0.08% or less
- P is an impurity contained in the steel and reduces the bending fatigue strength.
- the content of P is set to 0.08% or less.
- the P content is preferably 0.04% or less.
- Al 0.05% or less
- Al is an impurity contained in steel.
- the content of Al increases, bending straightness deteriorates.
- the content exceeds 0.05%, the bending straightness is significantly lowered even when the compound layer depth of the stress concentration portion is 5 ⁇ m or less. Therefore, the Al content is set to 0.05% or less.
- the Al content is preferably 0.03% or less.
- Cr Less than 0.20% Cr is an impurity contained in steel. When Cr is contained, the surface layer hardness becomes excessively high and the bending straightness is lowered. Therefore, the Cr content is preferably as low as possible. Therefore, the Cr content is less than 0.20%. The Cr content is preferably 0.10% or less.
- the non-tempered nitrocarburized part according to the present invention has a ⁇ 1> stress concentration portion at a position 0.05 mm from the surface, that is, the HV hardness of the surface layer is 410 to 480, and 1.0 mm from the surface, The HV hardness is 200 or more, the compound layer depth is 5 ⁇ m or less, and ⁇ 2> the metal structure of the dough is a bainite structure.
- (B-1) Surface hardness of stress concentration part In order to obtain a high bending fatigue strength of 800 MPa or more, it is necessary to set the HV hardness of the surface layer of the stress concentration portion to 410 or more. On the other hand, when the HV hardness of the surface layer of the stress concentration portion exceeds 480, the compound layer depth of the stress concentration portion is 5 ⁇ m or less for a crankshaft shape that is more likely to bend than before when soft nitriding. Even in such a case, there may be a case where it is not possible to obtain a practically sufficient bending straightness.
- the tempered soft nitriding component according to the present invention has an HV hardness of 410 to 480 at a position of 0.05 mm from the surface of the stress concentration portion.
- the HV hardness at a position of 0.05 mm from the surface of the stress concentration portion is preferably 420 or more, and more preferably 470 or less.
- (B-2) Internal hardness of stress concentration part In the case of non-tempered nitrocarburized parts, the durability ratio of the base material is lower than that of tempered nitrocarburized parts, so the stress concentration part has the same internal hardness as tempered nitrocarburized parts. However, the fatigue strength of the base material is lower than that of the tempered soft nitrided part. For this reason, in the non-tempered soft nitriding component, when the internal HV hardness is less than 200 in the stress concentration portion, the internal hardness is equal to that of the tempered component, and the HV hardness is 410. Even if it has the above high surface layer hardness, fatigue failure occurs from the inside, and it may be difficult to obtain a high fatigue strength of 800 MPa or more.
- the tempered soft nitriding component according to the present invention has an HV hardness of 200 or more at a position 1.0 mm from the surface of the stress concentration portion.
- the HV hardness at a position of 1.0 mm from the surface of the stress concentration portion is preferably 210 or more, and preferably 320 or less from the viewpoint of machinability.
- the compound layer depth of the stress concentration portion is 5 ⁇ m or less.
- the depth of the compound layer in the stress concentration portion is preferably 3 ⁇ m or less, and it is most preferable that there is no compound layer, that is, the compound layer depth is 0 ⁇ m.
- the metal structure (base material structure) of the fabric is a bainite structure.
- the bainite structure means that 80% or more of the metal structure of the dough is a bainite structure.
- the non-tempered nitrocarburized component has a lower durability ratio of the base material than the tempered nitrocarburized component, so it has the same internal hardness as the tempered nitrocarburized component in the stress concentration part.
- the fatigue strength of the base material is lower than that of the tempered soft nitriding component.
- the base material structure of the non-tempered nitrocarburized part is a bainite structure
- the durability ratio of the base material is higher than that of the ferrite-pearlite structure. Therefore, the bainite non-heat treated steel can obtain higher fatigue strength than the ferrite-pearlite non-heat treated steel having the same internal hardness in the stress concentration portion.
- the parts satisfying the above (B-1) to (B-4) are, for example, hot forging a steel material satisfying the chemical composition defined in the present invention at a temperature of 1000 ° C. or more, and the shaft diameter is 8
- RX gas is a kind of modified gas and is a trade name of gas.
- crankshaft is cited as an example of a non-tempered nitrocarburized part, for example, a crankshaft manufactured by hot forging a material that satisfies the chemical composition conditions defined in the present invention is used.
- RX gas and ammonia gas are mixed in a 1: 1 ratio and kept in an atmosphere of 600 ° C. for 2 hours for soft nitriding treatment, cooled in 90 ° C. oil, and then the pin fillet part Further, it is obtained by polishing the journal fillet portion by machining such as lapping.
- each steel slab was hot forged under conditions of a heating temperature of 1200 ° C. and a finishing temperature of 1000 to 1050 ° C. to form a steel bar having a diameter of 90 mm.
- the steel bar after hot forging was allowed to cool in the atmosphere and cooled to room temperature.
- Steels A to H in Table 1 are steels whose chemical compositions are within the range defined by the present invention, and Steels I to N are steels whose chemical compositions are outside the range defined by the present invention.
- the steel bar having a diameter of 90 mm thus obtained was heated to 1200 ° C. and hot forged at a finishing temperature of 1000 to 1050 ° C. to produce a steel bar having a diameter of 50 mm. All finished steel bars were allowed to cool in the atmosphere to room temperature.
- the groove bottom of R3 is the stress concentration part.
- the notch bottom of R3 becomes the stress concentration portion.
- the grooved Ono rotary bending fatigue test piece and the 4-point bending test piece obtained as described above were soft nitrided by holding RX gas and ammonia gas in a 1: 1 mixture at a temperature of 600 ° C. for 2 hours. Treated and then cooled in 90 ° C. oil.
- the target polishing depth was set to 0.03 mm for the groove bottom of the grooved Ono type rotary bending fatigue test piece and the notch bottom of the four-point bending test piece. Electropolishing was performed under the following conditions.
- the target of ⁇ w was 800 MPa or more.
- the target for bending straightness was that the gauge reading was 22000 ⁇ (corresponding to 2.2% bending straightening strain) or more.
- the test surface of the 4-point bending test piece is shown in FIG. The same applies to the test surface of the Ono type rotating bending fatigue test piece (not shown).
- Hardness is arbitrary at the position of 0.05 mm and the position of 1.0 mm from the groove bottom of R3 and the notch bottom of R3 according to “Vickers hardness test-test method” described in JIS Z 2244: 2009
- the HV hardness at 6 points was measured with a Vickers hardness tester with a test force of 2.94 N, and the values were arithmetically averaged to evaluate the surface hardness and the internal hardness.
- FIG. 5 the measurement position of the hardness in a 4-point bending test piece is shown typically. The same applies to the test surface of the Ono type rotating bending fatigue test piece (not shown).
- Compound layer depth of stress concentration portion Using the resin-embedded test piece used in the above ⁇ 3>, the compound layer depth of the stress concentration portion (hereinafter simply referred to as “compound layer depth”) was investigated.
- FIG. 6 schematically shows the measurement position of the compound layer depth in the 4-point bending test piece. The same applies to the test surface of the Ono type rotating bending fatigue test piece (not shown).
- Base material structure Using the resin-embedded test piece used in ⁇ 3>, the base material structure was investigated.
- the base material structure was observed with an optical microscope at a magnification of 400 times using the test piece subjected to the above-mentioned nital corrosion.
- Table 2 summarizes the above survey results.
- those described as “bainite” account for 80% or more of the bainite structure
- those described as “ferrite / pearlite” account for 80% or more of the ferrite / pearlite structure, described as “martensite”
- the martensite organization accounted for more than 80%.
- the chemical compositions of the steels I to N are out of the conditions defined in the present invention, so that they are inferior in bending fatigue characteristics or bending straightening properties.
- the C content of steel I which is a steel material, is below the range specified in the present invention.
- the internal hardness of the Ono type rotating bending fatigue test piece is as low as 195 in HV hardness, ⁇ w does not reach the target of 800 MPa or more, and is inferior in bending fatigue characteristics.
- the Mn content of steel J which is a steel material, is lower than the range specified in the present invention.
- the surface layer hardness of the Ono-type rotating bending fatigue test piece is as low as 405 in terms of HV hardness, and ⁇ w does not reach the target of 800 MPa or more, and is inferior in bending fatigue characteristics.
- the Mn content of steel K which is the steel material of the fabric, exceeds the range specified in the present invention.
- the compound layer depth is as small as 3 ⁇ m
- the surface hardness of the four-point bending test piece is as high as 512 in HV hardness, and the bend straightness has reached the target of 22000 ⁇ or more in gauge reading. It is inferior in bending straightness.
- the Cr content of steel L which is a steel material, exceeds the range specified in the present invention.
- the compound layer depth is as small as 2 ⁇ m
- the surface hardness of the 4-point bending test piece is as high as 505 in HV hardness, and the bending straightness has reached the target of 22000 ⁇ or more in gauge reading. It is inferior in bending straightness.
- Fn1 of steel M which is a steel material
- Fn1 of steel M which is a steel material
- the base material structure is a ferrite pearlite structure
- the surface hardness of the Ono rotary bending fatigue test piece is as high as 412 in HV hardness
- the internal hardness is 210 in HV hardness.
- the ⁇ w does not reach the target of 800 MPa or more and is inferior in bending fatigue characteristics.
- Fn1 of steel N which is a steel material of the fabric, exceeds the range specified in the present invention.
- the base material structure is a martensite structure and the compound layer depth is as small as 1 ⁇ m
- the surface hardness of the 4-point bend specimen is as high as 542 in HV hardness, and the bending straightness is read by the gauge. Therefore, the target of 22000 ⁇ or more is not reached, and the bending straightness is inferior.
- the compound layer depth of the four-point bending test piece is out of the conditions specified in the present invention, so that the bending straightness is inferior.
- the chemical composition of steel A which is a steel material, is within the range specified in the present invention, but the compound layer depth of the 4-point bending test piece is as large as 12 ⁇ m, and the bending straightness is gauged. It does not reach the target of 22000 ⁇ or more in reading, and is inferior in bending straightness.
- the chemical composition of steel B which is a steel material, is within the range specified in the present invention, but the compound layer depth of the 4-point bending test piece is as large as 9 ⁇ m, and the bending straightness is gauged. It does not reach the target of 22000 ⁇ or more in reading, and is inferior in bending straightness.
- the chemical composition of steel C which is a steel material, is within the range specified in the present invention, but the compound layer depth of the 4-point bending test piece is as large as 20 ⁇ m, and the bending straightness is gauged. It does not reach the target of 22000 ⁇ or more in reading, and is inferior in bending straightness.
- the non-tempered soft nitriding component of the present invention is excellent in bend straightening after soft nitriding treatment, and has a high bending fatigue strength of 800 MPa or more in a bending fatigue test, so that it is a component for automobiles, industrial machinery, construction machinery and the like.
- it can be used as a crankshaft and can cope with light weight and downsizing.
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Abstract
Description
C:0.35~0.50%、
Si:0.10~0.35%、
Mn:2.3~2.8%、
S:0.10%以下、
N:0.0030~0.0250%、
Cu:0~1.0%、
Mo:0~0.3%、
Ni:0~0.5%、
Ti:0~0.020%、
残部:Feおよび不純物で、
下記の式[1]で表されるFn1が3.10≦Fn1≦6.00であり、
不純物中のP、AlおよびCrがそれぞれ、P:0.08%以下、Al:0.05%以下およびCr:0.20%未満であり、
応力集中部において、
表面から0.05mm位置のHV硬さが410~480であり、
表面から1.0mm位置のHV硬さが200以上であり、
化合物層深さが5μm以下であり、かつ
生地の金属組織がベイナイト組織である、
非調質型軟窒化部品。
Fn1=(0.316C+0.122)×(0.7Si+1)×(5.1Mn-1.12)×(0.364Ni+1)×(2.16Cr+1)×(3Mo+1)・・・[1]
ただし、式[1]中の元素記号は、その元素の質量%での鋼中含有量を表す。
Cu:0.05~1.0%および
Mo:0.05~0.3%
から選択される1種以上を含有する、上記(1)に記載の非調質型軟窒化部品。
Ni:0.05~0.5%および
Ti:0.005~0.020%
から選択される1種以上を含有する、上記(1)または(2)に記載の非調質型軟窒化部品。
C:0.35~0.50%
Cは、内部硬さを高めて、曲げ疲労強度を高める作用を有する。所望の曲げ疲労強度を得るためには、0.35%以上のCを含有する必要がある。しかしながら、Cの含有量が多くなりすぎると、表層硬さがあまりにも大きくなって、応力集中部の化合物層深さが5μm以下であっても十分な曲げ矯正性を得ることができない。このため、Cの含有量を0.35~0.50%とした。Cの含有量は、0.38%以上とすることが好ましく、また、0.45%以下とすることが好ましい。
Siは、溶製時の脱酸用として必要な元素であり、かかる効果を得るためには少なくとも0.10%の含有量とする必要がある。しかしながら、Siの含有量が多くなりすぎると、応力集中部の化合物層深さが5μm以下であっても曲げ矯正性の過度な低下を招く。このため、Siの含有量を0.10~0.35%とした。Siの含有量は、0.15%以上とすることが好ましく、また、0.30%以下とすることが好ましい。
Mnは、Siと同様に脱酸作用を有する元素である。Mnは、軟窒化時に表層の固溶窒素量を増加させて表層硬さを向上させることにより、曲げ疲労強度を高める作用がある。このような効果を発揮させるためには、2.3%以上のMnを含有させる必要がある。一方、Mnの含有量が2.8%を超えると、表層硬さが過剰に高くなって、応力集中部の化合物層深さが5μm以下であっても曲げ矯正性が過度に低下する。したがって、Mnの含有量は2.3~2.8%とした。Mnの含有量は、2.4%以上とすることが好ましく、また、2.7%以下とすることが好ましい。
Sは、積極的に含有させれば、被削性を向上させる効果を有する。しかしながら、Sの含有量が0.10%を超えると、曲げ疲労強度と曲げ矯正性の著しい低下をきたす。したがって、Sの含有量を0.10%以下とした。Sの含有量は0.08%以下とすることが好ましい。被削性の向上効果を得る場合には、Sの含有量は、0.04%以上とすることが好ましい。
Nは、曲げ疲労強度および曲げ矯正性を向上させる元素である。このような効果を得るためには、0.0030%以上の量のNを含有させる必要がある。一方、0.0250%を超えるNを含有させてもその効果は飽和する。したがって、Nの含有量は0.0030~0.0250%とした。Nの含有量は、0.0080%以上とすることが好ましく、また、0.0220%以下とすることが好ましい。
Cuは、内部硬さを高めて、曲げ疲労強度を向上させる元素である。したがって、必要に応じてCuを含有させてもよい。しかしながら、Cuの含有量が1.0%を超えると、熱間加工性の低下をきたす。したがって、含有させる場合のCuの量を1.0%以下とした。Cuの量は、0.4%以下とすることが好ましく、0.3%以下とすれば一層好ましい。
Moは、フェライトを強化し、内部硬さを高めて、曲げ疲労強度を向上させる作用を有する。したがって、必要に応じてMoを含有させてもよい。しかしながら、0.3%を超える量のMoを含有させても上記の効果が飽和して、経済性が損なわれるばかりである。したがって、含有させる場合のMoの量を0.3%以下とした。Moの量は、0.2%以下とすることが好ましい。
Niは、靱性を高めて、曲げ矯正性を向上させる元素である。したがって、必要に応じてNiを含有させてもよい。しかしながら、0.5%を超える量のNiを含有させても上記の効果が飽和して、経済性が損なわれるばかりである。したがって、含有させる場合のNiの量を0.5%以下とした。Niの量は、0.3%以下とすることが好ましく、0.2%以下とすれば一層好ましい。
Tiは、窒化物を形成し、結晶粒を微細化して曲げ矯正時にクラックを進展させにくくすることで曲げ矯正性を向上させる元素である。したがって、必要に応じてTiを含有させてもよい。しかしながら、Tiの含有量が0.020%を超えると、窒化物が粗大になり、逆に、応力集中部の化合物層深さが5μm以下であっても曲げ矯正性が著しく低下する。したがって、含有させる場合のTiの量を0.020%以下とした。Tiの量は、0.015%以下とすることが好ましい。
本発明に係る非調質型軟窒化部品は、式中の元素記号を、その元素の質量%での鋼中含有量として、
Fn1=(0.316C+0.122)×(0.7Si+1)×(5.1Mn-1.12)×(0.364Ni+1)×(2.16Cr+1)×(3Mo+1)・・・[1]
で表されるFn1が、3.10~6.00の範囲内であるものである。
Pは、鋼に含有される不純物であり、曲げ疲労強度を低下させてしまう。特に、その含有量が0.08%を超えると、曲げ疲労強度の低下が著しくなる。したがって、Pの含有量を0.08%以下とした。Pの含有量は、0.04%以下とすることが好ましい。
Alは、鋼に含有される不純物である。Alの含有量が多くなると、曲げ矯正性の低下をきたす。特に、その含有量が0.05%を超えると、応力集中部の化合物層深さが5μm以下であっても曲げ矯正性の低下が著しくなる。したがって、Alの含有量を0.05%以下とした。Alの含有量は、0.03%以下とすることが好ましい。
Crは、鋼に含有される不純物である。Crを、含有すると表層硬さが過度に高くなり、曲げ矯正性を低下させるため、Crの含有量はできるだけ低くすることが望ましい。したがって、Crの含有量を0.20%未満とした。Crの含有量は、0.10%以下とすることが好ましい。
本発明に係る非調質型軟窒化部品は、<1>応力集中部において、表面から0.05mm位置、すなわち表層のHV硬さが410~480であり、表面から1.0mm位置、すなわち内部のHV硬さが200以上であり、化合物層深さが5μm以下であり、かつ<2>生地の金属組織がベイナイト組織であるものである。
800MPa以上の高い曲げ疲労強度を得るためには、応力集中部の表層のHV硬さを410以上にする必要がある。一方、応力集中部の表層のHV硬さが480を超える場合には、軟窒化時に従来よりも大きな曲がりが生じやすいクランクシャフト形状に対しては、たとえ応力集中部の化合物層深さが5μm以下であっても、実用上十分な曲げ矯正性を得ることができないことがある。
非調質型軟窒化部品の場合、調質型軟窒化部品と比べて母材の耐久比が低いので、応力集中部において、調質型軟窒化部品と同等の内部硬さを有していても、母材の疲労強度は調質型軟窒化部品に比べ低くなる。このため、非調質型軟窒化部品では、応力集中部において、内部のHV硬さが200を下回る場合には、たとえ内部硬さが調質型部品と同等で、しかも、HV硬さで410以上の高い表層硬さを有していても、内部を起点とした疲労破壊が起こり、800MPa以上という高い疲労強度を得ることが難しくなることがある。
応力集中部における化合物層を薄くすることで、曲げ疲労強度を低下させることなく、曲げ矯正性を改善することができる。深さ5μmを超える化合物層が残っておれば曲げ矯正性の大きな改善が期待できない。
上述のように、生地の鋼材が、前記(A)項で述べた化学組成である本発明に係る非調質型軟窒化部品は、生地の金属組織(母材組織)がベイナイト組織である。本発明においてベイナイト組織とは、生地の金属組織の80%以上がベイナイト組織であるものをいう。
・電流値:0.14A、
・研磨面積:小野式回転曲げ疲労試験片の場合:160mm2、
4点曲げ試験片の場合:96mm2、
・研磨時間:小野式回転曲げ疲労試験片の場合:970秒、
4点曲げ試験片の場合:590秒。
・電流値:0.14A、
・研磨面積:小野式回転曲げ疲労試験片の場合:160mm2、
4点曲げ試験片の場合:96mm2、
・研磨時間:小野式回転曲げ疲労試験片の場合:490秒、
4点曲げ試験片の場合:300秒。
小野式回転曲げ疲労試験を、室温、大気中、回転数3000rpmの両振りの条件で行い、曲げ疲労強度(以下、「σw」という。)を調査した。
4点曲げ試験片のノッチ底に2mmの歪ゲージを接着し、ゲージが断線するまで曲げ矯正歪を付与した。ゲージが断線した時点でのゲージの読みを曲げ矯正性として評価した。
小野式回転曲げ疲労試験片については、試験片の中心部を通り試験片の長さ方向に平行な断面が表れるように切断した。また、4点曲げ試験片については、試験片の長さ方向に平行でかつ溝の方向に垂直な断面が表れるように切断した。そして、各々の切断面が被検面となるよう、小野式回転曲げ疲労試験片のR3の溝近傍および4点曲げ試験片のR3のノッチ近傍を樹脂に埋め込んだ後、前記の面が鏡面仕上げになるように研磨し、ビッカース硬度計を使用して応力集中部の表面硬さ(以下、単に「表面硬さ」という。)および応力集中部の内部硬さ(以下、単に「内部硬さ」という。)を調査した。4点曲げ試験片の被検面を図4に示す。小野式回転曲げ疲労試験片の被検面についても同様である(図示は省略)。
前記〈3〉で用いた樹脂埋めした試験片を使用して、応力集中部の化合物層深さ(以下、単に「化合物層深さ」という。)の調査を行った。
前記〈3〉で用いた樹脂埋めした試験片を使用して、母材組織の調査を行った。
Claims (3)
- 生地の鋼材の化学組成が、質量%で、
C:0.35~0.50%、
Si:0.10~0.35%、
Mn:2.3~2.8%、
S:0.10%以下、
N:0.0030~0.0250%、
Cu:0~1.0%、
Mo:0~0.3%、
Ni:0~0.5%、
Ti:0~0.020%、
残部:Feおよび不純物で、
下記の式[1]で表されるFn1が3.10≦Fn1≦6.00であり、
不純物中のP、AlおよびCrがそれぞれ、P:0.08%以下、Al:0.05%以下およびCr:0.20%未満であり、
応力集中部において、
表面から0.05mm位置のHV硬さが410~480であり、
表面から1.0mm位置のHV硬さが200以上であり、
化合物層深さが5μm以下であり、かつ
生地の金属組織がベイナイト組織である、
非調質型軟窒化部品。
Fn1=(0.316C+0.122)×(0.7Si+1)×(5.1Mn-1.12)×(0.364Ni+1)×(2.16Cr+1)×(3Mo+1)・・・[1]
ただし、式[1]中の元素記号は、その元素の質量%での鋼中含有量を表す。 - 前記生地の鋼材の化学組成が、質量%で、
Cu:0.05~1.0%および
Mo:0.05~0.3%
から選択される1種以上を含有する、請求項1に記載の非調質型軟窒化部品。 - 前記生地の鋼材の化学組成が、質量%で、
Ni:0.05~0.5%および
Ti:0.005~0.020%
から選択される1種以上を含有する、請求項1または2に記載の非調質型軟窒化部品。
Priority Applications (5)
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JP2016546396A JP6304386B2 (ja) | 2014-09-02 | 2015-08-10 | 非調質型軟窒化部品 |
CN201580047298.4A CN107075628B (zh) | 2014-09-02 | 2015-08-10 | 非调质型软氮化部件 |
KR1020177008608A KR101928680B1 (ko) | 2014-09-02 | 2015-08-10 | 비조질형 연질화 부품 |
EP15837445.4A EP3190199B1 (en) | 2014-09-02 | 2015-08-10 | Non-tempered soft-nitrided component |
US15/506,296 US20170275741A1 (en) | 2014-09-02 | 2015-08-10 | Non-thermal refined nitrocarburized component |
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JP2014-178001 | 2014-09-02 | ||
JP2014178001 | 2014-09-02 |
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WO2016035519A1 true WO2016035519A1 (ja) | 2016-03-10 |
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US (1) | US20170275741A1 (ja) |
EP (1) | EP3190199B1 (ja) |
JP (1) | JP6304386B2 (ja) |
KR (1) | KR101928680B1 (ja) |
CN (1) | CN107075628B (ja) |
WO (1) | WO2016035519A1 (ja) |
Cited By (3)
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JP2018053962A (ja) * | 2016-09-27 | 2018-04-05 | いすゞ自動車株式会社 | クランクシャフトの製造方法 |
WO2020090816A1 (ja) * | 2018-10-29 | 2020-05-07 | 日本製鉄株式会社 | 窒化部品粗形材、および窒化部品 |
CN112695257A (zh) * | 2020-11-30 | 2021-04-23 | 江苏联峰能源装备有限公司 | 一种大规格直接用非调质钢制备方法 |
Families Citing this family (2)
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JP2017122500A (ja) * | 2016-01-08 | 2017-07-13 | 株式会社神戸製鋼所 | 大型クランク軸 |
US12031577B2 (en) * | 2020-02-25 | 2024-07-09 | Nippon Steel Corporation | Crankshaft and method of manufacturing the same |
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- 2015-08-10 US US15/506,296 patent/US20170275741A1/en not_active Abandoned
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- 2015-08-10 EP EP15837445.4A patent/EP3190199B1/en active Active
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EP3190199A4 (en) | 2018-04-11 |
JPWO2016035519A1 (ja) | 2017-07-27 |
EP3190199B1 (en) | 2020-02-26 |
CN107075628A (zh) | 2017-08-18 |
CN107075628B (zh) | 2019-03-08 |
KR101928680B1 (ko) | 2018-12-12 |
JP6304386B2 (ja) | 2018-04-04 |
US20170275741A1 (en) | 2017-09-28 |
EP3190199A1 (en) | 2017-07-12 |
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