WO2019111833A1 - 合金鋼粉 - Google Patents
合金鋼粉 Download PDFInfo
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- WO2019111833A1 WO2019111833A1 PCT/JP2018/044315 JP2018044315W WO2019111833A1 WO 2019111833 A1 WO2019111833 A1 WO 2019111833A1 JP 2018044315 W JP2018044315 W JP 2018044315W WO 2019111833 A1 WO2019111833 A1 WO 2019111833A1
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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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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/16—Both compacting and sintering in successive or repeated steps
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/002—Making metallic powder or suspensions thereof amorphous or microcrystalline
- B22F9/004—Making metallic powder or suspensions thereof amorphous or microcrystalline by diffusion, e.g. solid state reaction
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/02—Making ferrous alloys by powder metallurgy
- C22C33/0207—Using a mixture of prealloyed powders or a master alloy
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/02—Making ferrous alloys by powder metallurgy
- C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
- C22C33/0264—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements the maximum content of each alloying element not exceeding 5%
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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
- C22C38/12—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
- C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
- B22F2009/041—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by mechanical alloying, e.g. blending, milling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2201/00—Treatment under specific atmosphere
- B22F2201/01—Reducing atmosphere
- B22F2201/013—Hydrogen
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
- B22F2998/10—Processes characterised by the sequence of their steps
Definitions
- the present invention relates to an alloyed steel powder, and more particularly to an alloyed steel powder having excellent flowability, formability and compressibility without containing Ni, Cr and Si.
- powder metallurgy technology components with complicated shapes can be manufactured with a shape very close to the product shape (so-called near net shape) and with high dimensional accuracy. Therefore, it is possible to significantly reduce the cutting cost by producing the parts using powder metallurgy technology. Therefore, powder metallurgy products manufactured by powder metallurgy technology are widely used as various machine parts. Furthermore, in recent years, the demand for powder metallurgy technology has further increased in order to cope with the miniaturization, weight reduction and complexity of parts.
- alloy steel powder used in powder metallurgy is also advanced.
- alloy steel powder is required to be excellent in fluidity.
- alloyed steel powder is required to be able to be manufactured by the current powder manufacturing process without requiring additional steps.
- alloy steel powder for powder metallurgy contains an element for improving hardenability as an alloy component
- alloy steel powder which does not contain Ni, which has the highest alloy cost is required. There is.
- an alloyed steel powder not containing Ni one to which at least one of Mo, Cr, Si and Cu is added is widely used.
- Cr and Si have a problem that they are oxidized in an RX gas (endothermic modified gas) atmosphere generally used as an atmosphere gas for sintering in a manufacturing process of sintered parts. Therefore, when sintering a compact produced using alloy steel powder containing Cr or Si, it is necessary to carry out the sintering process under a high degree of atmosphere control using N 2 or H 2 is there. As a result, even if the raw material cost can be reduced by not using Ni, there is a problem that the part manufacturing cost increases, and as a result, the total cost can not be reduced.
- Mo-based alloy steel powders using Mo as a hardenability improving element have no fear of oxidation as seen in Cr and Si described above, and the decrease in the compressibility due to the addition of elements is small. Therefore, it is suitable for highly compressible, complex shaped parts. Moreover, since Mo is superior to Ni in hardenability, it exhibits excellent hardenability even with a small amount of addition. From the above reasons, the Mo-based alloy steel powder is considered to be the most suitable alloy system to meet the above requirements (1) to (4).
- Patent Document 1 As a technique relating to Mo-based alloy steel powder, for example, in Patent Document 1, excellent compressibility, in which 0.2 to 10.0 mass% of Mo is diffused and attached to the surface of iron-based powder containing Mn, Alloy steel powder having cold forgeability has been proposed.
- Patent Document 2 discloses a technique relating to an Fe—Si—Mn—C alloy steel powder from which a sintered body suitable for a quench strength member or the like can be obtained.
- the rattler value which is an index of formability, is a very good value as low as 0.31% when formed at a forming pressure of 6 t / cm 2 .
- Patent Document 3 discloses a technology relating to an alloy steel powder in which Ni is partially diffused in an iron-based powder, and a rattler value at a forming of 6 t / cm 2 shows a good value of 0.4%.
- Patent Document 4 discloses a technology relating to Fe-Mn-Cr alloy steel powder subjected to vacuum reduction, and shows a good value of 0.35% rattler value at 6 t / cm 2 forming.
- Patent Document 5 discloses a technique in which the surface of iron powder is plated with copper to make the rattler value extremely low, about 0.2 to 0.3%.
- Patent Documents 1 to 5 have the following problems.
- Patent Document 1 has excellent compressibility and cold forgeability.
- Patent Document 1 only defines the composition of the alloyed steel powder, and although there is a mention of compressibility, the formability is not considered, and the alloyed steel powder proposed in Patent Document 1 is It did not meet the requirement (3) above.
- the alloy steel powder disclosed in Patent Document 2 is excellent in formability, it contains Si, so it is necessary to sinter in a specially controlled atmosphere to prevent the oxidation of Si described above. Yes, does not meet the requirement of (4) above. Further, the alloyed steel powder described in Patent Document 2 has poor compressibility, and the density of the green compact obtained by forming the alloyed steel powder is as extremely low as 6.77 g / cm 3 at 6 t / cm 2 . If the green density is low as described above, there is a concern in terms of fatigue strength. Therefore, the alloyed steel powder disclosed in Patent Document 2 did not satisfy the above requirements (2) and (4).
- the alloyed steel powder disclosed in Patent Document 3 needs to contain Ni in a large amount of 30% by mass, and therefore does not satisfy the requirement (4).
- the alloyed steel powder disclosed in Patent Document 4 also needs to contain Cr, so that it is necessary to control the atmosphere during sintering, and also does not satisfy the above requirement (4).
- the alloyed steel powder disclosed in Patent Document 5 requires an additional raw material powder production process of plating on the powder.
- the amount of Cu to be plated is also 20 mass% or more, which is very large compared to the Cu content (about 2 to 3 mass%) in ordinary sintered steel, and as a result, the cost of alloyed steel powder increases. Accompany. Therefore, the alloyed steel powder disclosed in Patent Document 5 does not satisfy the above requirement (4).
- the present invention has been made in view of the above situation, and it is an object of the present invention to provide an alloyed steel powder having excellent fluidity, formability and compressibility without containing Ni, Cr and Si. .
- the present inventors found out that the said objective would be achieved by the following structure, and completed this invention. That is, the gist configuration of the present invention is as follows.
- the Mo content in the iron-based alloy is 0.4 to 1.8% by mass,
- the median diameter D50 on a weight basis is 40 ⁇ m or more,
- the number average value of the area envelopment degree defined as (particle cross sectional area / area within the envelope) is 0.70 to 0. 86, alloy steel powder.
- the alloyed steel powder of the present invention has excellent flowability, formability and compressibility, even without containing Ni, Cr and Si. In addition, it is not necessary to contain Ni, which has a high alloy cost, or Cr and Si that require annealing in a special atmosphere, and no additional manufacturing process such as plating is necessary, so the alloy steel powder of the present invention Is low cost and can be manufactured with current powder manufacturing processes.
- the alloyed steel powder of the present invention is an alloyed steel powder made of an iron-based alloy containing Mo.
- iron-based alloy refers to an alloy containing 50% by mass or more of Fe. Therefore, in other words, the alloy steel powder of the present invention is a Mo-containing iron-based alloy powder.
- the alloyed steel powder of the present invention may be a prealloyed steel powder.
- the alloy steel powder of the present invention contains Mo as an essential alloying element. Sintering diffusion can be promoted by containing Mo, which is an ⁇ -phase forming element. In addition, Mo has an effect of stabilizing secondary particles generated by heat treatment by ⁇ -phase sintering.
- the Mo content in the iron-based alloy constituting the alloy steel powder is set to 0.4% by mass or more in order to stabilize the secondary particles and to control the area envelope degree to the range described later.
- the Mo content is preferably 0.5% by mass or more, and more preferably 0.6% by mass or more.
- the amount of Mo in the iron-based alloy is set to 1.8% by mass or less.
- the Mo content is preferably 1.7% by mass or less, and more preferably 1.6% by mass or less.
- the component composition of the alloyed steel powder of the present invention is not particularly limited except for the above-mentioned Fe and Mo contents, and it may be any composition.
- the Fe content may be 50% by mass or more, but is preferably 80% or more, more preferably 90% or more, and still more preferably 95% or more.
- the upper limit of the Fe content is not particularly limited.
- the component composition of the iron-based alloy may be Mo: 0.4 to 1.8%, and the balance may be a component composition including the balance Fe and unavoidable impurities.
- Examples of the unavoidable impurities include C, O, N, S, and P.
- C content into 0.02 mass% or less.
- the O content is preferably 0.3% by mass or less, and more preferably 0.25% by mass or less.
- N content into 0.004 mass% or less.
- S content into 0.03 mass% or less.
- the P content is preferably 0.1% by mass or less.
- the iron-based alloy can optionally contain additional alloying elements.
- additional alloying element for example, one or both of Cu and Mn can be used.
- the Mn content in the alloy powder is preferably 0.5% by mass or less.
- excessive addition of Cu, like Mo reduces the powder's compressibility. Therefore, it is preferable to make Cu content into 0.5 mass% or less.
- the alloy steel powder of the present invention does not have to contain Ni, Cr and Si, which have been used conventionally. Since Ni causes an increase in alloy cost, it is preferable to suppress the content of Ni in the entire alloy steel powder to 0.1 mass% or less, and it is more preferable to substantially not contain Ni. Further, as described above, Cr is susceptible to oxidation and requires annealing atmosphere control, so it is preferable to suppress the Cr content in the entire alloy steel powder to 0.1 mass% or less, substantially It is more preferable not to contain. With regard to Si, for the same reason as Cr, it is preferable to suppress the Si content in the entire alloy steel powder to 0.1 mass% or less, and it is more preferable to substantially not contain Si. In addition, "does not substantially contain” here means that it does not contain except as an unavoidable impurity, and therefore containing as an unavoidable impurity is accept
- D50 40 ⁇ m or more
- D50 median diameter D50
- the ratio of fine particles in the entire alloy steel powder becomes too high, and as a result , The compressibility is reduced. Therefore, D50 is 40 ⁇ m or more. It is preferable that D50 be 65 ⁇ m or more.
- the upper limit of D50 is not particularly limited, but if it is excessively large, the mechanical properties after sintering will be reduced. Therefore, in consideration of the characteristics after sintering, it is preferable to set D50 to 120 ⁇ m or less.
- the maximum particle size of the alloy steel powder is not particularly limited, but is preferably 212 ⁇ m or less.
- the maximum particle size of 212 ⁇ m or less means that the alloy steel powder is a powder which passes through a sieve with an opening of 212 ⁇ m.
- Area envelope degree 0.70 to 0.86
- the number of area envelope degrees defined as (particle cross sectional area / area within envelope) for particles having a circle equivalent diameter of 50 to 200 ⁇ m It is important to set the average value to 0.70 or more and 0.86 or less.
- area envelope degree the number average value of the area envelope degree defined as (particle cross sectional area / area within the envelope) is simply referred to as “area envelope degree”.
- the area envelopment degree is an index indicating the degree of unevenness of the particle surface, and indicates that as the area envelopment degree is lower, the unevenness of the particle surface is more.
- the area envelope degree is preferably 0.85 or less, more preferably 0.83 or less.
- the area envelope degree is 0.70 or more.
- particle circularity decreases not only when the unevenness of the particle surface is increased but also when the particles are elongated like needles. Since the expanded particles do not contribute to the improvement of the formability, the degree of particle circularity is not suitable as an index of the formability.
- the area envelope degree can be determined by image analysis of a projected image of particles.
- Examples of devices capable of calculating the area envelope degree include Morphologi G3 manufactured by Malvern Co., and CAMSIZER X2 manufactured by Virde Scientific Technology Co., and any of them can be used. Further, in the measurement of the area envelope degree, at least 10,000 particles, preferably 20,000 or more particles are measured, and the area envelope degree is calculated as the number average value of those particles.
- the alloyed steel powder of the present invention can be produced by heat treating, pulverizing and classifying the raw material powder whose component composition and particle size distribution are controlled.
- the component composition of the raw material powder may be adjusted so that the component composition of the finally obtained alloy steel powder satisfies the above-mentioned condition.
- the component composition of the raw material powder is the component composition of the alloy steel powder It should be the same as
- the raw material powder may be produced, for example, from molten steel prepared in advance so that the component composition satisfies the above-mentioned condition, and manufactured from the molten steel by any method.
- the raw material powder it is preferable to use an atomized alloy steel powder manufactured by an atomizing method in which adjustment of alloying elements is easy, and among the atomizing methods, manufacturing cost is low and mass production is easy. It is more preferable to use water atomized alloy steel powder.
- the average particle size of the raw material powder is not particularly limited. However, since the average particle size after heat treatment is almost equal to the average particle size of the raw material powder, the particle size close to the particle size of the alloy steel powder to be produced from the viewpoint of suppressing the yield decrease in the subsequent sieving process etc. It is preferable to use a raw material powder having
- the number frequency of particles having a particle diameter of 20 ⁇ m or less occupied in the whole of the raw material powder is set to 60% or more.
- the number frequency is set to 60% or more.
- the area envelope degree can be set to 0.86 or less.
- the number frequency is 90% or less.
- the measurement method of the number frequency includes a laser diffraction method, an image analysis method, and the like, and any method may be used.
- fills the conditions of the said number frequency can be obtained by adjusting the spraying conditions at the time of atomization, for example.
- particles having a particle size of more than 20 ⁇ m and particles having a particle size of 20 ⁇ m or less may be mixed.
- the maximum particle size of the raw material powder is not particularly limited, but is preferably 212 ⁇ m or less.
- the maximum particle diameter of 212 ⁇ m or less means that the raw material powder is a powder which passes through a sieve with an opening of 212 ⁇ m.
- the raw material powder is heat treated. Since the raw material powder produced by the atomizing method etc. generally contains oxygen and carbon, its compressibility and sinterability are low. Therefore, by performing deoxidation and decarburization by heat treatment, oxygen and carbon contained in the powder can be removed, and the compressibility and sinterability of the alloyed steel powder can be improved.
- a reducing atmosphere is preferable, and a hydrogen atmosphere is particularly suitable.
- heat treatment may be performed under vacuum.
- the preferred heat treatment temperature is in the range of 800-1100 ° C. If the temperature is less than 800 ° C., the reduction of oxygen becomes insufficient. On the other hand, if the temperature exceeds 1100 ° C., sintering of the powders during heat treatment proceeds excessively, and the area envelope degree increases.
- decarburizing it is preferable to set the atmospheric dew point at the time of heat treatment to 20 ° C. or higher. However, when the dew point exceeds 70 ° C., deoxidation by hydrogen is suppressed, so the dew point is preferably 70 ° C. or less.
- the raw material powder when heat treatment is performed, usually, the raw material powder is in a sintered and solidified state, and therefore, pulverization and classification are performed to a desired particle diameter. That is, removal of coarse powder by additional grinding or classification with a sieve having a predetermined opening is performed as necessary to achieve a desired particle size.
- the alloyed steel powder of the present invention can be made into a sintered body by pressure forming and sintering as in the conventional powder for powder metallurgy.
- auxiliary materials can be optionally added to the alloy steel powder.
- the auxiliary material for example, one or both of copper powder and graphite powder can be used.
- a powdery lubricant can be further mixed with the alloy steel powder.
- a lubricant can be applied to or adhered to a mold used for pressure molding for molding.
- any lubricant can be used as the lubricant, such as metal soaps such as zinc stearate and lithium stearate, and amide-based waxes such as ethylenebisstearic acid amide.
- metal soaps such as zinc stearate and lithium stearate
- amide-based waxes such as ethylenebisstearic acid amide.
- the method of the said pressure forming is not specifically limited, As long as it is a method which can shape
- the molded product obtained as described above has a high density and is excellent in moldability. Further, since the alloy steel powder of the present invention does not require an element such as Cr or Si which is required to control the sintering atmosphere, it can be sintered by a conventional inexpensive process.
- Example 1 The raw material powder which adjusted component composition and particle size distribution was manufactured, and alloy steel powder was manufactured by heat-processing the said raw material powder then. Specific procedures will be described below.
- iron-based powders having different component compositions and particle size distributions were manufactured by the water atomization method as the raw material powders.
- the Mo content of the raw material powder is shown in Table 1.
- the Mo content of the raw material powder is equal to the Mo content of the finally obtained alloyed steel powder.
- the remainder other than Mo is Fe and an unavoidable impurity.
- the said raw material powder did not contain Ni, Cr, and Si except an unavoidable impurity, therefore content of Ni, Cr, and Si was 0.1 mass% or less, respectively.
- Table 1 also shows the number frequency of particles having a particle diameter of 20 ⁇ m or less occupied in the whole of the raw material powder.
- the number frequency was measured by image analysis using Morphologi G3 manufactured by Malvern.
- the raw material powder was heat-treated (holding temperature: 880 ° C., holding time: 1 h) in a hydrogen atmosphere with a dew point of 30 ° C. to obtain an alloyed steel powder.
- Image analysis was performed on each of the obtained alloy steel powder, and the number average value of the area envelopment degree of particles having a circle equivalent diameter of 50 to 200 ⁇ m was measured.
- Morphellog G3 manufactured by Malvern Co., Ltd. was used as in the image analysis of the raw material powder.
- D50 of the said alloy steel powder was measured by sieving.
- the density of the green compact can be regarded as an indicator of the compressibility of the alloyed steel powder. From the viewpoint of compressibility, a density: 7.20 Mg / m 3 or more is regarded as a pass.
- the alloyed steel powder satisfying the conditions of the present invention has excellent flowability, compressibility, and formability.
- the alloy steel powder of the present invention does not need to contain Ni, which has a high alloy cost, or Cr and Si that require annealing in a special atmosphere, and does not require additional manufacturing processes such as plating. Therefore, it is low cost and can be manufactured by the current powder manufacturing process.
- Example 2 As the raw material powder, as in Example 1 except that iron-based powder (pre-alloyed steel powder) containing one or both of Cu and Mn in addition to Mo and the balance being Fe and unavoidable impurities is used as the raw material powder. Alloy steel powder was produced under the following conditions.
- the iron-based powder is an atomized iron-based powder produced by an atomizing method.
- the number frequency of particles having a particle diameter of 20 ⁇ m or less contained in the iron-based powder used is shown in Table 2.
- the number frequency was measured by the same method as in Example 1.
- the raw material powder was heat-treated under the same conditions as in Example 1 to obtain alloyed steel powder.
- the amounts of Mo, Cu, and Mn contained in the alloyed steel powder are the same as the used raw material powder and are as shown in Table 2.
- Image analysis was performed on each of the obtained alloy steel powder, and the number average value of the area envelopment degree of particles having a circle equivalent diameter of 50 to 200 ⁇ m was measured.
- the image analysis was performed in the same manner as in Example 1. Moreover, D50 of partial diffusion alloy steel powder was measured by sieving.
- the density of the green compact can be regarded as an indicator of the compressibility of the partial diffusion alloy steel powder. From the viewpoint of compressibility, a density: 7.20 Mg / m 3 or more is regarded as a pass.
- the rattler test was carried out in the same manner as in Example 1, and the rattler value of the green compact was measured. For the rattle value, 0.4% or less is considered as a pass.
- the measurement results are as shown in Table 2. From this result, even when the iron-based powder contains one or both of Cu and Mn, the alloy steel powder satisfying the conditions of the present invention has excellent flowability, compressibility, and formability. I understand.
Abstract
Description
(1)流動性に優れること。
(2)圧縮性が良好であること。
(3)成形性が高いこと。
(4)低コストであること。
前記鉄基合金におけるMo含有量が0.4~1.8質量%であり、
重量基準のメジアン径D50が40μm以上であり、
前記合金鋼粉に含まれる粒子のうち、円相当径が50~200μmの粒子に関して、(粒子断面積/包絡線内面積)として定義される面積包絡度の個数平均値が0.70~0.86である、合金鋼粉。
本発明の合金鋼粉は、Moを含有する鉄基合金からなる合金鋼粉である。ここで、「鉄基合金」とは、Feを50質量%以上含有する合金を指すものとする。したがって、言い換えると、本発明の合金鋼粉は、Moを含有する鉄基合金粉末である。本発明の合金鋼粉は、予合金鋼粉であってよい。
本発明の合金鋼粉は、Moを必須の合金化元素として含有する。α相生成元素であるMoを含有させることにより、焼結拡散を促進することができる。また、Moには、熱処理によって生成した2次粒子をα相焼結によって安定化させる効果がある。本発明では、2次粒子を安定化させ、面積包絡度を後述する範囲に制御するために、合金鋼粉を構成する鉄基合金におけるMo含有量を0.4質量%以上とする。Mo含有量は、0.5質量%以上とすることが好ましく、0.6質量%以上とすることがより好ましい。一方、Mo含有量が1.8質量%を超えると、焼結促進効果が飽和し、むしろ圧縮性の低下を招く。そのため、前記鉄基合金におけるMo量を1.8質量%以下とする。Mo含有量は1.7質量%以下とすることが好ましく、1.6質量%以下とすることがより好ましい。
上記合金鋼粉の重量基準のメジアン径D50(以下、単に「D50」という)が40μm未満であると、該合金鋼粉全体に占める微細な粒子の比率が高くなりすぎ、その結果、圧縮性が低下する。そのため、D50は40μm以上とする。D50は65μm以上とすることが好ましい。一方、D50の上限値は特に限定されないが、過度に大きいと焼結後の機械的特性が低下する。そのため、焼結後の特性まで考慮すると、D50を120μm以下とすることが好ましい。
本発明の合金鋼粉においては、前記合金鋼粉に含まれる粒子のうち、円相当径が50~200μmの粒子に関して、(粒子断面積/包絡線内面積)として定義される面積包絡度の個数平均値を0.70以上0.86以下とすることが重要である。なお、以下の説明において、円相当径が50~200μmの粒子についての、(粒子断面積/包絡線内面積)として定義される面積包絡度の個数平均値を、単に「面積包絡度」と記す。
次に、本発明の合金鋼粉を製造する方法について説明する。本発明の合金鋼粉は、成分組成と粒径分布を制御した原料粉末を熱処理し、粉砕、分級することによって製造することができる。
上記原料粉末の成分組成は、最終的に得られる合金鋼粉の成分組成が上述した条件を満たすように調整すればよく、通常は、前記原料粉末の成分組成を、上記合金鋼粉の成分組成と同じとすればよい。前記原料粉末は、例えば、成分組成が上記条件を満たすように予め調整された溶鋼を用意し、前記溶鋼から任意の方法で製造すればよい。
次いで、上記原料粉末を熱処理する。アトマイズ法などによって製造された原料粉末には、一般的に酸素および炭素が含まれているため、圧縮性と焼結性が低い。そこで、熱処理によって脱酸および脱炭することにより、粉末に含まれる酸素および炭素を除去し、合金鋼粉の圧縮性と焼結性を向上させることができる。
本発明の合金鋼粉は、従来の粉末冶金用粉末と同様に、加圧成形した後、焼結することによって焼結体とすることができる。
成分組成と粒径分布を調整した原料粉末を製造し、次いで前記原料粉末を熱処理することによって合金鋼粉を製造した。具体的な手順を以下に説明する。
前記原料粉末として、Moに加えてさらにCuおよびMnの一方または両方を含有し、残部がFeおよび不可避的不純物からなる鉄基粉末(予合金鋼粉)を使用した点以外は実施例1と同様の条件で、合金鋼粉を製造した。前記鉄基粉末は、アトマイズ法により製造したアトマイズ鉄基粉末とした。
Claims (3)
- Moを含有する鉄基合金からなる合金鋼粉であって、
前記鉄基合金におけるMo含有量が0.4~1.8質量%であり、
重量基準のメジアン径D50が40μm以上であり、
前記合金鋼粉に含まれる粒子のうち、円相当径が50~200μmの粒子に関して、(粒子断面積/包絡線内面積)として定義される面積包絡度の個数平均値が0.70~0.86である、合金鋼粉。 - 前記鉄基合金におけるNi、Cr、およびSiの含有量が、それぞれ0.1質量%以下である、請求項1に記載の合金鋼粉。
- 前記鉄基合金が、CuおよびMnの一方または両方を含有する、請求項1または2に記載の合金鋼粉。
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2021044869A1 (ja) * | 2019-09-06 | 2021-03-11 | Jfeスチール株式会社 | 粉末冶金用鉄基予合金粉末、粉末冶金用拡散接合粉末、粉末冶金用鉄基合金粉末、および焼結鍛造部材 |
WO2021100613A1 (ja) * | 2019-11-18 | 2021-05-27 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉、粉末冶金用鉄基混合粉及び焼結体 |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5645966B2 (ja) * | 1979-06-01 | 1981-10-30 | ||
JPS59129753A (ja) | 1983-01-13 | 1984-07-26 | Kawasaki Steel Corp | 高強度焼結材料用合金鋼粉 |
JPH0247202A (ja) | 1988-08-10 | 1990-02-16 | Hitachi Powdered Metals Co Ltd | 耐熱耐摩耗性焼結合金用鋼粉 |
JPH059501A (ja) | 1991-07-04 | 1993-01-19 | Mitsubishi Steel Mfg Co Ltd | 焼結用鉄系粉末およびその製造方法 |
JPH07157803A (ja) * | 1993-05-18 | 1995-06-20 | Kawasaki Steel Corp | 粉末冶金用水アトマイズ鉄粉およびその製造方法 |
JPH07188714A (ja) * | 1993-12-28 | 1995-07-25 | Kobe Steel Ltd | 成形性の優れた鉄系粉末 |
JP2002146403A (ja) | 2000-08-31 | 2002-05-22 | Kawasaki Steel Corp | 粉末冶金用合金鋼粉 |
JP2002348601A (ja) | 2001-05-21 | 2002-12-04 | Tsurumi Soda Co Ltd | 粉末冶金法及び焼結金属体 |
WO2015045273A1 (ja) * | 2013-09-26 | 2015-04-02 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉および鉄基焼結体の製造方法 |
Family Cites Families (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0751721B2 (ja) * | 1985-06-25 | 1995-06-05 | トヨタ自動車株式会社 | 焼結用低合金鉄粉末 |
JPH0689361B2 (ja) * | 1987-11-04 | 1994-11-09 | トヨタ自動車株式会社 | 被削性に優れた高強度鉄系粉末およびその製造方法 |
CN1104570A (zh) * | 1993-05-18 | 1995-07-05 | 川崎制铁株式会社 | 粉末冶金用的水雾化铁粉及其制造方法 |
JPH07118714A (ja) * | 1993-10-26 | 1995-05-09 | Nippon Steel Corp | 高炉炉壁補修方法 |
JP4060092B2 (ja) * | 2002-02-20 | 2008-03-12 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉およびその焼結体 |
CA2476836C (en) | 2003-08-18 | 2009-01-13 | Jfe Steel Corporation | Alloy steel powder for powder metallurgy |
JP4371003B2 (ja) | 2003-08-18 | 2009-11-25 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉 |
CN100515613C (zh) * | 2004-04-22 | 2009-07-22 | 杰富意钢铁株式会社 | 粉末冶金用混合粉体 |
US7384446B2 (en) * | 2004-04-22 | 2008-06-10 | Jfe Steel Corporation | Mixed powder for powder metallurgy |
JP5929967B2 (ja) * | 2013-06-07 | 2016-06-08 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉 |
JP6227903B2 (ja) * | 2013-06-07 | 2017-11-08 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉および鉄基焼結体の製造方法 |
JP6222189B2 (ja) | 2014-12-05 | 2017-11-01 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉および焼結体 |
WO2016088333A1 (ja) | 2014-12-05 | 2016-06-09 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉および焼結体 |
JP6302882B2 (ja) * | 2015-09-04 | 2018-03-28 | 株式会社三共 | 遊技機 |
WO2017043094A1 (ja) * | 2015-09-11 | 2017-03-16 | Jfeスチール株式会社 | 粉末冶金用混合粉末の製造方法、焼結体の製造方法、および焼結体 |
SE542547C2 (en) * | 2015-09-18 | 2020-06-02 | Jfe Steel Corp | Iron-based sintered body and method of manufacturing the same |
WO2019111834A1 (ja) * | 2017-12-05 | 2019-06-13 | Jfeスチール株式会社 | 部分拡散合金鋼粉 |
-
2018
- 2018-11-30 US US16/769,240 patent/US11441212B2/en active Active
- 2018-11-30 KR KR1020207018382A patent/KR102316651B1/ko active IP Right Grant
- 2018-11-30 CN CN201880078188.8A patent/CN111432957B/zh active Active
- 2018-11-30 CA CA3084316A patent/CA3084316C/en active Active
- 2018-11-30 EP EP18887066.1A patent/EP3722022B1/en active Active
- 2018-11-30 JP JP2019510986A patent/JP6690781B2/ja active Active
- 2018-11-30 WO PCT/JP2018/044315 patent/WO2019111833A1/ja unknown
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5645966B2 (ja) * | 1979-06-01 | 1981-10-30 | ||
JPS59129753A (ja) | 1983-01-13 | 1984-07-26 | Kawasaki Steel Corp | 高強度焼結材料用合金鋼粉 |
JPH0247202A (ja) | 1988-08-10 | 1990-02-16 | Hitachi Powdered Metals Co Ltd | 耐熱耐摩耗性焼結合金用鋼粉 |
JPH059501A (ja) | 1991-07-04 | 1993-01-19 | Mitsubishi Steel Mfg Co Ltd | 焼結用鉄系粉末およびその製造方法 |
JPH07157803A (ja) * | 1993-05-18 | 1995-06-20 | Kawasaki Steel Corp | 粉末冶金用水アトマイズ鉄粉およびその製造方法 |
JPH07188714A (ja) * | 1993-12-28 | 1995-07-25 | Kobe Steel Ltd | 成形性の優れた鉄系粉末 |
JP2002146403A (ja) | 2000-08-31 | 2002-05-22 | Kawasaki Steel Corp | 粉末冶金用合金鋼粉 |
JP2002348601A (ja) | 2001-05-21 | 2002-12-04 | Tsurumi Soda Co Ltd | 粉末冶金法及び焼結金属体 |
WO2015045273A1 (ja) * | 2013-09-26 | 2015-04-02 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉および鉄基焼結体の製造方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP3722022A4 |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2021044869A1 (ja) * | 2019-09-06 | 2021-03-11 | Jfeスチール株式会社 | 粉末冶金用鉄基予合金粉末、粉末冶金用拡散接合粉末、粉末冶金用鉄基合金粉末、および焼結鍛造部材 |
US11542579B2 (en) | 2019-09-06 | 2023-01-03 | Hyundai Motor Company | Iron-based prealloy powder, iron-based diffusion-bonded powder, and iron-based alloy powder for powder metallurgy using the same |
WO2021100613A1 (ja) * | 2019-11-18 | 2021-05-27 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉、粉末冶金用鉄基混合粉及び焼結体 |
JPWO2021100613A1 (ja) * | 2019-11-18 | 2021-12-02 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉、粉末冶金用鉄基混合粉及び焼結体 |
JP7147963B2 (ja) | 2019-11-18 | 2022-10-05 | Jfeスチール株式会社 | 粉末冶金用合金鋼粉、粉末冶金用鉄基混合粉及び焼結体 |
EP4063041A4 (en) * | 2019-11-18 | 2023-01-18 | JFE Steel Corporation | ALLOY STEEL POWDER FOR POWDER METALLURGY, MIXED IRON POWDER FOR POWDER METALLURGY, AND SINTERED BODY |
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