Cu-BASED POWDER

Abstract

To provide a Cu-based powder allowed to prepare a Cu-based material that Fe in the Fe-based material is not to excessively diffuse toward the Cu-based material if the Cu-based and Fe-based materials are both used for diffusion-bonding or infiltration and is excellent in diffuseness to the Fe-based material, and moreover to suppress the hindrance to diffusion-bonding, infiltration or sintering by a SiO2 oxide film because of a reduced solid-solubility limit of Si to a Cu phase and it is less apt to form a SiO2 oxide film over a powder surface.SOLUTION: A Cu-based powder comprises an Fe content of 1.5 mass% or higher and 5.0 mass% or lower, a Mn content of 0.3 mass% or higher and 6.0 mass% or lower, a Si content of 0.25 mass% or lower, an O content of 0.25 mass% or higher and 0.55 mass% or lower, and the remainder of Cu and inevitable impurities.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to Cu-based powders. Specifically, it is a Cu-based powder containing Fe and Mn. When a Cu-based material composed of the Cu-based powder in the present invention and an Fe-based material are used together for diffusion bonding or infiltration, Fe in the Fe-based material does not excessively diffuse to the Cu-based material side, and a Cu-based material excellent in diffusibility to the Fe-based material can be produced. Moreover, since the solid solution amount of Si in the Cu phase is small and it is difficult to form a SiO2 oxide film on the powder surface, the present invention relates to a Cu-based powder that can suppress the inhibition of diffusion bonding, infiltration, and sintering by the SiO2 oxide film.

Background Art

[0002] There are cases where a Cu-based powder, a compacted powder formed body or a sintered body produced using the Cu-based powder (hereinafter sometimes referred to as a "Cu-based material") and a compacted powder formed body or a sintered body of an Fe-based powder (hereinafter sometimes referred to as an "Fe-based material", and particularly the Fe-based material to be infiltrated is sometimes referred to as an "Fe-based base material") are combined and used by diffusion bonding, infiltration, or the like.

[0003] However, since Cu can dissolve 4.5% by mass of Fe, there is a problem that Fe in the Fe-based material excessively diffuses into the Cu-based material.

[0004] As a method for preventing the excessive diffusion of Fe in the Fe-based material into the Cu-based material and maintaining the diffusibility of the Cu-based material to the Fe-based material side, there is a method of containing Fe or Mn in the Cu-based powder.

[0005] Generally, when Fe or Mn is contained in a Cu-based powder, since Fe is difficult to dissolve in Cu, it is often added as an alloy, and Mn is often added as an alloy or a single powder.

[0006] However, when using scrap containing Si in the raw materials during alloy production or when Si inevitably mixes in from refractories such as the furnace body, Si may dissolve in the Cu phase of the produced Cu-based powder.

[0007] When Si is mixed in during the production of an alloy, it may form a SiO2 oxide film on the powder surface, or change the melting point or strength, making diffusion bonding, infiltration, and sintering difficult, and there is a risk of impairing the properties of Cu-based powders containing Fe and Mn.

[0008] Therefore, Cu-based powders containing Fe or Mn are required to have a low unintended solid solution amount of Si in the Cu phase.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0010] Patent Document 1 discloses an atomized powder of a Cu-based metal composed of Cu or a Cu alloy in which the total content of impurity elements whose standard formation free energy of the lowest condensed phase oxide in the temperature range of 900 °C or lower is lower than that of Zn oxide is 400 ppm or less.

[0011] The method for removing impurities disclosed in Patent Document 1 is a method in which it is dissolved in the atmosphere and the impurity elements are floated on the molten metal surface as an oxide slag and removed.

[0012] However, in the impurity removal method disclosed in Patent Document 1, when the dissolution amount of the scrap containing Si is large or when Si is supplied from a refractory such as a furnace body, Si cannot be completely removed, and there is a risk that Si will dissolve in the Cu phase of the Cu-based powder.

[0013] In addition, although the decrease in sinterability is suppressed by setting the total content of impurity elements to 400 ppm or less, the sinterability of Cu-based powders containing Fe or Mn is originally low, and in powders having the same total content of impurity elements as in Patent Document 1, it is necessary to further suppress the decrease in sinterability.

[0014] As a result of conducting numerous trial productions and experiments to solve the above problems, the inventor has found that if a Cu-based material is made of Cu-based powder in which the Fe content is 1.5 mass% or more and 5.0 mass% or less, the Mn content is 0.3 mass% or more and 6.0 mass% or less, the Si content is 0.25 mass% or less, the O content is 0.25 mass% or more and 0.55 mass% or less, and the balance is Cu and inevitable impurities, when used together with an Fe-based material and diffusion bonded or infiltrated, Fe in the Fe-based material does not excessively diffuse to the Cu-based material side, and it becomes a Cu-based material excellent in diffusibility to the Fe-based material. Moreover, since the amount of Si dissolved in the Cu phase in the Cu-based powder is small, it is difficult to form a SiO2 oxide film on the powder surface, so it has been found that inhibition of diffusion bonding, infiltration, and sintering due to the SiO2 oxide film can be suppressed, and the above technical problems have been solved.

Means for Solving the Problems

[0015] The above technical problems can be solved by the present invention as follows.

[0016] The present invention relates to Cu-based powder in which the Fe content is 1.5 mass% or more and 5.0 mass% or less, the Mn content is 0.3 mass% or more and 6.0 mass% or less, the Si content is 0.25 mass% or less, the O content is 0.25 mass% or more and 0.55 mass% or less, and the balance is Cu and inevitable impurities.

[0017] The present invention also relates to the above Cu-based powder in which the amount of Si dissolved in a phase containing 80 mass% or more of Cu is 0.2 mass% or less.

[0018] The present invention also relates to the above Cu-based powder in which the L value, which is the lightness of the powder, is 35 or more.

[0019] The present invention also relates to the above Cu-based powder that has been subjected to rust prevention treatment and / or segregation prevention treatment.

[0020] The present invention also relates to the above-described Cu-based powder containing 0.1 out mass% or more and 1.0 out mass% or less of a lubricant.

[0021] The present invention also relates to the above-described Cu-based powder for powder metallurgy.

[0022] The present invention also relates to the above-described Cu-based powder for infiltration.

[0023] The present invention also relates to the above-described Cu-based powder for infiltration containing 0.2 mass% or more and 3.0 mass% or less of Zn and 0.03 out mass% or more and 1.0 out mass% or less of Si powder.

[0024] The present invention also relates to a compacted body of the above-described Cu-based powder.

[0025] The present invention also relates to a sintered body of the above-described Cu-based powder.

[0026] The present invention also relates to a method for producing the above-described Cu-based powder.

Advantages of the Invention

[0027] The present invention relates to a Cu-based powder in which the Fe content is 1.5 mass% or more and 5.0 mass% or less, the Mn content is 0.3 mass% or more and 6.0 mass% or less, the Si content is 0.25 mass% or less, the O content is 0.25 mass% or more and 0.55 mass% or less, and the balance is Cu and unavoidable impurities.

[0028] When Mn is made into an alloy of Cu and Fe, Si mainly becomes a liquid phase of Mn2SiO4 near the boiling temperature of about 1700K to 1750K. When Mn is made into a single powder or a partially alloyed powder, it mainly becomes a liquid phase of Fe2SiO4.

[0029] Since all of the above liquid phases are suspended in the molten Cu, they are dispersed in the produced powder. However, complex oxides such as Mn2SiO4 and Fe2SiO4 in the powder have low reactivity with Cu, Fe, and Mn below the liquid-phase generation temperature of Cu, so it is difficult to affect the properties of the Cu-based powder.

[0030] Therefore, even if a scrap raw material containing Si or a refractory such as a furnace body containing Si is used in the production, the amount of Si dissolved in the Cu phase of the Cu-based powder decreases, and it becomes difficult to form a SiO2 oxide film on the powder surface. Thus, the decrease in the reactivity of the outermost surface of the powder can be suppressed, and it is not necessary to remove complex oxides such as Mn2SiO4 and Fe2SiO4 during powder production.

[0031] In addition, in the Cu-based powder of the present invention, Fe is added so that it becomes 1.5 mass% to 5.0 mass%. Therefore, when a Cu-based material and an Fe-based material are used in combination, it is possible to suppress the excessive diffusion of Fe in the Fe-based material to the Cu-based material side.

[0032] Moreover, since the addition of Fe does not cause a significant drop in the liquid-phase generation temperature, problems such as melting and softening during use are less likely to occur even during use at high temperatures.

[0033] Also, the strength of the powder can be improved.

[0034] In addition, since Mn is easily soluble in both Cu and Fe, the diffusibility of the Cu-based material to the Fe-based material side can be improved.

[0035] In addition, the melting point and strength can be adjusted by the addition amount of Mn.

Embodiments for Carrying Out the Invention

[0036] The Fe content of the Cu-based powder in the present invention is preferably 1.5 mass% to 5.0 mass%, more preferably 2.0 mass% to 4.0 mass%.

[0037] If the Fe content is less than 1.5% by mass, the solid solubility amount (yield) in the Cu phase may decrease due to the formation of a composite oxide of Si and O. If the content exceeds 5.0% by mass, Fe may not completely dissolve in Cu during raw material melting, and component segregation may occur.

[0038] The form of Fe is preferably alloy powder with Cu.

[0039] The Mn content of the Cu-based powder in the present invention is preferably 0.3% to 6.0% by mass, more preferably 0.8% to 5.0% by mass.

[0040] If it is less than 0.3% by mass, when making Mn into an alloy of Cu and Fe, the yield in the Cu phase may decrease due to the formation of a composite oxide of Si and O.

[0041] Also, when the content exceeds 6.0% by mass, when making Mn into an alloy of Cu and Fe, the amount of Mn oxide generated increases and the viscosity of the molten metal becomes high. Therefore, if the powder is manufactured by the atomization method, there is a risk of nozzle blockage.

[0042] Also, when the content exceeds 6.0% by mass, when making Mn into single powder or partially alloyed powder, when alloying with heat during use or when manufacturing partially alloyed powder, it is difficult to obtain a uniform structure with short-time heat treatment, so there is a risk of reduced economic efficiency.

[0043] The form of Mn in the Cu-based powder is not limited, and it may be any of single powder, alloy powder, and partially alloyed powder.

[0044] Since Mn is easily soluble in Cu and Fe, even when mixed as single powder, it can be easily alloyed by heat during use such as when sintering or infiltration is performed.

[0045] The manufacturing method of the single powder of Mn is not particularly limited, and it may be manufactured by a known method such as a pulverization method.

[0046] When mixing Mn as a single powder, there is a risk of segregation. Also, since it may be used in applications other than heating applications such as sintering or infiltration, alloy powder or partially alloyed powder of Cu and Fe is a more preferable form.

[0047] Si contained in the Cu-based powder in the present invention is derived from inevitable impurities, except when intentionally added as Si powder.

[0048] Si, which is an inevitable impurity, usually combines with O in the molten metal during the production of Cu-based powder to form SiO2 and floats to the upper part of the molten metal. However, when the amount of scrap containing Si dissolved is large or when Si is supplied from refractories such as the furnace body, it cannot be completely removed, and Si dissolves in the Cu phase of the Cu-based powder.

[0049] When Si dissolves in the Cu phase of the Cu-based powder, a SiO2 oxide film is formed on the powder surface.

[0050] Since SiO2 cannot be reduced in an atmosphere such as a reducing atmosphere gas with a dew point of about -30°C containing hydrogen (hereinafter referred to as "normal reducing atmosphere"), when a SiO2 oxide film is formed on the surface of the Cu-based powder, the reactivity of the outermost surface of the powder is significantly reduced, and thus the diffusivity of atoms, electrical conductivity, thermal conductivity, the ability as a catalyst, etc. are reduced.

[0051] The content of Si is preferably 0.25 mass% or less, more preferably 0.008 mass% to 0.15 mass%.

[0052] When the content of Si exceeds 0.25 mass%, the amount of Si dissolved in the Cu phase increases, and there is a risk that the influence of the SiO2 oxide film on the powder surface on the reactivity of the Cu-based powder will increase.

[0053] The content of O in the present invention is preferably 0.25 mass% to 0.55 mass%, more preferably 0.3 mass% to 0.5 mass%.

[0054] If the O content is less than 0.25% by mass, the production amount of Fe2SiO4 or Mn2SiO4 is small, and there is a risk that Si will dissolve in the Cu phase.

[0055] Also, when the O content exceeds 0.55% by mass, O becomes excessive and Fe and Mn are oxidized. As a result, the yield of the Cu phase decreases, and the reactivity of the outermost surface of the Cu-based powder decreases, so there is a risk that the diffusivity of atoms, electrical conductivity, thermal conductivity, the ability as a catalyst, etc. will decrease.

[0056] The method for producing the alloy powder of the Cu-based powder in the present invention is not particularly limited, and known atomization methods such as water atomization method, gas atomization method, and centrifugal atomization method may be used.

[0057] In the Cu-based powder of the present invention, it is preferable that the L value, which is the brightness of the powder, is 35 or more.

[0058] Since the Cu-based powder in the present invention contains Fe2SiO4 or Mn2SiO4, it may be difficult to measure the amount of oxygen, which is a general index of deterioration due to changes in the powder over time.

[0059] However, if the L value, which is the brightness of the powder, is 35 or more, it can be estimated that the amount of oxygen is low even when it is difficult to measure the amount of oxygen in the Cu phase, and the decrease in reactivity due to oxidation of the outermost surface of the Cu-based powder can be suppressed. Therefore, it is possible to suppress the decrease in the diffusivity of atoms, electrical conductivity, thermal conductivity, the ability as a catalyst, etc.

[0060] For the Cu-based powder in the present invention, a rust prevention treatment and / or a segregation prevention treatment can be applied to part or all of the powder constituting the Cu-based powder.

[0061] As segregation that can occur in the Cu-based powder, there is sedimentation segregation caused by the difference in fluidity of each mixed powder.

[0062] The fluidity of the powder may change when the surface of the powder is oxidized. Even if there is no segregation at the beginning of production, segregation may become significant in a relatively short time depending on the storage environment.

[0063] When segregation occurs in the Cu-based powder, variations in the average particle size are likely to occur, which may lead to variations in the powder supply amount to the mold or variations in the sintered density.

[0064] By subjecting part or all of the powder constituting the Cu-based powder to a segregation prevention treatment, variations in the average particle size can be suppressed.

[0065] The segregation prevention treatment is not particularly limited, and examples include surface modification treatments that reduce fluidity, such as a decrease in specific surface area by granulation of the powder or porosity by reduction of powder containing oxides, and addition of various functional groups by chemical reactions or physical adsorption with organic compounds such as addition of a binder.

[0066] In addition, in the case of rust prevention treatment, not only segregation but also a decrease in reactivity due to oxidation of the outermost surface of the powder can be suppressed, so a decrease in atomic diffusivity, electrical conductivity, thermal conductivity, ability as a catalyst, etc. can be suppressed.

[0067] The rust preventive agent is not particularly limited, but an organic compound containing one or more elements coordinating to Cu per molecule is preferable, and more preferably the organic compound having 3 to 30 carbon atoms.

[0068] Examples of the rust preventive agent and segregation preventive agent include benzotriazole and machine oil.

[0069] A lubricant can be added to the Cu-based powder in the present invention. By adding a lubricant, the Cu-based powder becomes easy to mold in a mold or the like.

[0070] The content of the lubricant is preferably 0.1 out mass% to 1.0 out mass%, and more preferably 0.2 out mass% to 0.8 out mass%.

[0071] If it is less than 0.1 out mass%, the effect of improving lubricity is low, and if it is added in excess of 1.0 out mass%, there is a risk of deterioration in moldability.

[0072] The lubricant is not particularly limited, but metal soaps such as zinc stearate and EBS-based waxes are preferred.

[0073] The Cu-based powder in the present invention can be used in powder metallurgy applications.

[0074] Since the Cu-based powder in the present invention is a Cu-based powder containing Fe and Mn, when the Fe-based material and the Cu-based material are diffusion-bonded in a multilayer structure, it becomes difficult for Fe of the Fe-based material to diffuse excessively to the Cu-based material side, and the diffusibility of the Cu-based material to the Fe-based material side can be improved.

[0075] In addition, since the solid solution amount of Si in the Cu phase of the Cu-based powder is small, it is difficult to form a SiO2 oxide film on the powder surface. Therefore, the green compact of the Cu-based powder can be easily sintered in a normal sintering atmosphere without being inhibited from diffusion by the SiO2 oxide film.

[0076] In addition, by solid-soluting Fe or Mn into the Cu phase, the strength of the sintered body can be increased.

[0077] In addition, Fe solid-soluted in the Cu phase can increase the strength of the sintered body by being precipitated by heat treatment after sintering.

[0078] The Cu-based powder in the present invention can be used in infiltration applications.

[0079] Since the Cu-based powder in the present invention is a Cu-based powder containing Fe and Mn, it becomes difficult for Fe of the Fe-based substrate to diffuse excessively to the Cu-based infiltrant side, and the diffusibility of the Cu-based infiltrant to the Fe-based substrate side can be improved.

[0080] In addition, since the solid solution amount of Si in the Cu phase of the Cu-based powder is small, it is difficult to form a SiO2 oxide film on the powder surface. Therefore, when the green compact of the Cu-based powder is infiltrated into the Fe-based substrate in a normal infiltration atmosphere, it is difficult for the wettability to decrease due to the SiO2 oxide film.

[0081] In addition, Fe and Mn dissolve in the Cu phase, making it difficult for the so-called erosion phenomenon to occur, where Fe in the Fe-based substrate melts into the Cu-based impregnating material in contact with the Fe and the surface of the Fe-based substrate becomes rough or forms depressions.

[0082] Fe2SiO4 or Mn2SiO4 contained in the Cu-based powder in the present invention remains on the surface of the Fe-based substrate after impregnation (hereinafter, this residue is referred to as "slag").

[0083] If slag is generated, when laminating and impregnating a plurality of Fe-based substrates and a Cu-based impregnating material to increase the production amount of sintered parts per unit time, it is possible to prevent adhesion between the Fe-based substrates.

[0084] Since the liquid phase of Fe2SiO4 or Mn2SiO4 generated during the production of the Cu-based powder in the present invention is suspended in the molten Cu and dispersed in the produced powder, it is difficult for variations to occur in the generation of slag, and slag can be stably generated.

[0085] When using the Cu-based powder in the present invention as an impregnating material, it may contain Zn.

[0086] The addition of Zn has the effect of lowering the melting point of the impregnating material and improving the wettability between the impregnating material and the substrate, thereby improving the impregnation rate.

[0087] The Zn content is preferably 0.2% by mass to 3.0% by mass, more preferably 0.5% by mass to 2.0% by mass.

[0088] If the Zn content is less than 0.2% by mass, no improvement in wettability can be observed. Also, if it exceeds 3.0% by mass, the evaporation amount of Zn during the impregnation process increases, the yield of the impregnating material deteriorates, and there is a risk that the impregnation rate decreases.

[0089] In addition, there is a risk that the evaporated Zn will contaminate the sintering furnace.

[0090] The form of Zn is not limited and can be any of elemental powder, alloy powder, or partially alloyed powder, but alloy powder is preferred. This is because elemental Zn powder is more likely to become gaseous than alloy powder.

[0091] The method for manufacturing elemental Zn powder is not particularly limited, and it may be manufactured by known methods such as a pulverization method or an atomization method.

[0092] The Cu-based powder for infiltration in the present invention may contain Si powder.

[0093] Unlike Si that is mixed as an inevitable impurity during the production of Cu-based powder, Si powder is added as elemental powder to Cu-based powder containing Fe and Mn.

[0094] Si powder is easily oxidized during the temperature increase process in infiltration, and it is difficult to form a SiO2 oxide film on the surface of the Cu-based powder. Therefore, it does not affect the basic infiltration characteristics such as a decrease in the wettability between the Cu-based powder and the Fe-based substrate.

[0095] If Si powder is added to the Cu-based powder for infiltration, it becomes a residue component and the infiltration rate decreases. Therefore, it can finely adjust the infiltration rate and compensate for the shortage of residue components.

[0096] Si powder is preferably added so that the content is 0.03 out mass% to 1.0 out mass%, and more preferably, it is added so that the content is 0.04 out mass% to 0.8 out mass%.

[0097] If the Si powder content is less than 0.03 out mass%, a decrease in the infiltration rate and an increase in the residue component are not observed. Also, if it contains more than 1.0 out mass%, there is a risk of excessive decrease in the infiltration rate, excessive increase in the residue component, and segregation of the residue component due to segregation of the Si powder.

[0098] The method for manufacturing Si powder is not particularly limited, and it may be manufactured by known methods such as a pulverization method.

[0099] The average particle diameter of each powder constituting the Cu-based powder in the present invention is preferably 1 μm to 300 μm.

[0100] If it exceeds 300 μm, there is a risk of component segregation due to uneven mixing, and if it is less than 1 μm, the handleability deteriorates and the powder becomes expensive, resulting in a decrease in economic efficiency.

[0101] The Cu-based powder in the present invention can be used to produce a compacted powder body by a known method.

[0102] In addition, the Cu-based powder for infiltration in the present invention can be used to produce an infiltration material by a known method such as powder compacting.

Examples

[0103] Examples and comparative examples of the present invention are shown, but the present invention is not limited thereto.

[0104] <Cu-based powder> (Production of Cu-based powder with Mn added as an alloy) … A Copper ingot, iron ingot, Fe-Mn ingot, and Si ingot were weighed so as to have the compositions shown in Table 1 and melted in a high-frequency melting furnace. The powder produced by the water atomization method in which the molten alloy components are brought into contact with high-pressure water of about 15 MPa while being dropped to cause rapid solidification was sieved to 200 mesh or less to produce a Cu-based powder.

[0105] (Production of Cu-based powder with Mn added as a single powder) … B Copper ingot, iron ingot, and Si ingot were weighed so as to have the compositions shown in Table 1 and melted in a high-frequency melting furnace. The powder produced by the water atomization method in which the molten alloy components are brought into contact with high-pressure water of about 15 MPa while being dropped to cause rapid solidification was sieved to 200 mesh or less to produce a Cu-Fe-Si alloy powder. The produced Cu-Fe-Si alloy powder and Mn powder produced by pulverizing Mn ingot and sieving to 200 mesh or less were mixed with a rocking mixer so as to have the composition shown in Table 1 to produce a Cu-based powder.

[0106] For the powders of Comparative Examples 2, 4 to 7, the deoxidation operation of the molten metal was adjusted so that O was below the scope of the present invention. For the powder of Comparative Example 3, the deoxidation operation of the molten metal was adjusted so that O exceeded the scope of the present invention.

[0107] (Inspection of Cu-based powder) Cu, Fe, Mn, Si, and Zn contained in the Cu-based powder of A, B, or C to F described later were quantified using an ICP emission spectrometer iCAP7600 (manufactured by Thermo Fisher Scientific K.K.), and it was inspected whether each element was within the numerical range of the present invention. When it was within the numerical range of the present invention, O was quantified using an oxygen analyzer EMGA-920 (manufactured by Horiba, Ltd.), and it was confirmed that the amounts of all elements in the Cu-based powder of the examples were within the numerical range of the present invention.

[0108] The L value was measured using a spectrocolorimeter SE 6000 (manufactured by Nippon Denshoku Industries Co., Ltd.).

[0109] (Measurement of the amount of Si solid solution in the Cu phase) 1 g of the Cu-based powder of A or B was embedded in a cold resin, and using an energy dispersive X-ray spectrometer (EDS) attached to a field emission scanning electron microscope FE-SEM (manufactured by JEOL Ltd.) for a sample polished with 0.3 μm abrasive grains, elemental mapping was performed at 400 times magnification. Ten particles in which a Cu phase containing Si was detected in the field of view were selected, and point analysis or surface analysis was performed to quantify Si in the Cu phase.

[0110] As a result of the quantification, a location containing Fe or Mn and O at the same position as Si and having a Cu amount of less than 80% by mass at that position was determined to be an oxide phase of Fe or Mn and Si (not a Cu phase), and it was confirmed that the amount of Si in the other Cu phases was 0.2% by mass or less on average for 10 particles (detection limit: 0.01% by mass).

[0111] (Application of Cu-based powder to powder metallurgy) (Manufacture of Cu-based powder for powder metallurgy) … C 0.3 mass% of zinc stearate was added as a lubricant to the Cu-based powder of (i) or (ii), and the mixture was mixed with a rocking mixer to produce a Cu-based powder for powder metallurgy.

[0112] (Sinterability of Cu-based powder) The Cu-based powder for powder metallurgy of (iii) was formed into a ring shape with an outer diameter of 14 mm × inner diameter of 7 mm × height of 8 mm, and powder compacted so that the forming density was 6.3 g / cm 3 and sintered by holding at 1273 K for 30 minutes in a hydrogen atmosphere to obtain each sintered body. The density change before and after sintering of each sintered body was calculated based on the following (Equation 1).

[0113] (Equation 1) (Sintered density - Forming density) / Forming density × 100

[0114] (Application to infiltration of Cu-based powder) (Manufacture of Cu-based powder for infiltration with Mn added as an alloy or elemental powder)… (ii) 0.5 mass% of zinc stearate was added as a lubricant to the Cu-based powder of (i) or (ii), and the mixture was mixed with a rocking mixer to produce a Cu-based powder for infiltration.

[0115] (Manufacture of Cu-based powder for infiltration with Mn as elemental powder and Zn as alloy)… (iii) Copper ingot, iron ingot, zinc ingot and silicon ingot were weighed to have the compositions as shown in Table 1 and melted in a high-frequency melting furnace. The powder produced by the water atomization method of rapidly solidifying by contacting the molten alloy component with high-pressure water of about 15 MPa while dropping was sieved to 200 mesh or less to produce a Cu-Fe-Zn-Si alloy powder. The produced Cu-Fe-Zn-Si alloy powder and the Mn powder produced by pulverizing the Mn ingot and sieving to 200 mesh or less were mixed with a rocking mixer so as to have the composition shown in Table 1 to produce a Cu-based powder.

[0116] As described above, after inspecting the Cu-based powder and confirming that each element is within the numerical range of the present invention, Cu-based powder and Si powder produced by pulverizing Si ingot and sieving it to 200 mesh or less so as to have the composition shown in Table 1 were added at 0.05 out mass%, and zinc stearate at 0.5 out mass% as a lubricant was added, and the Cu-based powder for infiltration was produced by mixing with a rocking mixer.

[0117] (Infiltration property of Cu-based powder) After mixing electrolytic Cu powder, graphite powder and atomized Fe powder so that Cu is 1.5 mass%, C is 1.0 mass%, and the balance is Fe, 13.7 g of the mixed powder with 0.8 mass% of zinc stearate added was formed into a rectangular prism shape with a width of 12 mm × a length of 30 mm × a thickness of 5 mm and a density of 6.8 g / cm 3 Two Fe-based substrates were produced by molding so as to obtain a compacted body.

[0118] Two infiltration materials were produced by compacting the Cu-based powder for infiltration in an amount of 80% by volume with respect to the pores of the produced Fe-based substrate into a thin plate shape with a width of 12 mm × a length of 30 mm × a thickness of 1 mm. The infiltration material was placed on the Fe-based substrate, and another Fe-based substrate and the infiltration material were placed thereon, and infiltration was performed by a one-step infiltration method.

[0119] As the infiltration conditions, after heating at 823 K for 30 minutes to remove the lubricant in the infiltration material, heating was performed at 1403 K for 30 minutes. The atmosphere in the sintering furnace was a mixed gas atmosphere of hydrogen:nitrogen = 3:1.

[0120] When the residue was uniformly generated and easily peeled off, it was judged as ○, and when the residue was not generated, the amount of generation was too large, there was unevenness in the amount of generation, or the Fe-based substrates were adhered to each other, it was judged as ×.

[0121] The infiltration rate was calculated based on the following formula 2 (Equation 1) for the lower substrate.

Equation

[0122] The compositions and results of the examples and comparative examples are shown in Table 1.

[0123]

Table 1

[0124] As shown in Examples 1 to 8, in the Cu-based powder of the present invention, even if it contains Si, as long as the amounts of all elements in the Cu-based powder are within the scope of the present invention, the amount of Si dissolved in the Cu phase is small, and it has been shown that the decrease in the reactivity of the outermost surface of the Cu-based powder due to the SiO2 oxide film can be suppressed.

[0125] In addition, since the amount of Si dissolved in the Cu phase in the Cu-based powder for powder metallurgy in the present invention is small, it has been shown that it also has excellent sinterability.

[0126] In addition, since the impregnation material made of the Cu-based powder for impregnation in the present invention has a small amount of Si dissolved in the Cu phase, the impregnation rate is high, and stable residues are generated on the surface of the base material after impregnation due to Fe2SiO4 or Mn2SiO4, so it has been shown that it is also excellent in productivity.

[0127] In the Cu-based powder of Comparative Example 1, since the Si content was more than 0.25% by mass and the amount of Si dissolved in the Cu phase was more than 0.2% by mass, the sinterability was lower than that of Example 3 in powder metallurgy applications, the impregnation rate also decreased in impregnation applications, and the amount of residue generated was large and difficult to remove.

[0128] In the Cu-based powder of Comparative Example 2, although the amount of Si dissolved in the Cu phase was 0.2% by mass or less, since O was less than 0.25% by mass, the production amount of Fe2SiO4 or Mn2SiO4 was less than that of Example 3 with a similar composition. In powder metallurgy applications, the sinterability was low, the impregnation rate also decreased in impregnation applications, the amount of residue was small, and Fe-based base materials adhered to each other.

[0129] In the Cu-based powder of Comparative Example 3, the amount of Si dissolved in the Cu phase was 0.2 mass% or less, but O was more than 0.55 mass%, and the L value was also less than 35. Therefore, expansion occurred in the sintered body in powder metallurgy applications, wettability decreased in infiltration applications, and the infiltration rate decreased. In addition, Fe and Mn were oxidized, and a large amount of raw materials was required to achieve the desired yield, resulting in a decrease in economic efficiency.

[0130] In the Cu-based powder of Comparative Example 4, O was less than 0.25 mass%. Compared with Example 6 having a similar composition, the production amount of Fe2SiO4 or Mn2SiO4 was small, and the amount of Si dissolved in the Cu phase was more than 0.2 mass%. Therefore, in powder metallurgy applications, the sinterability was low, and in infiltration applications, the infiltration rate also decreased, and adhesion between Fe-based substrates and adhesion of residues were observed.

[0131] In the Cu-based powder of Comparative Example 5, the amount of Si dissolved in the Cu phase was 0.2 mass% or less, but O was less than 0.25 mass%. Therefore, compared with Example 8 having a similar composition, the production amount of Fe2SiO4 or Mn2SiO4 was small. As a result, in infiltration applications, the infiltration rate decreased, the amount of residues was small, and Fe-based substrates adhered to each other.

[0132] In the Cu-based powders of Comparative Examples 6 and 7, the Si content was as low as 0.03 mass%, and the amount of Si dissolved in the Cu phase was also small. Therefore, in powder metallurgy applications, the density change was positive. However, since O was less than 0.25 mass%, compared with Examples 1 and 2 having a similar composition, the production amount of Fe2SiO4 or Mn2SiO4 was small. Therefore, in powder metallurgy applications, the sinterability was lower than that of Examples 1 and 2, in infiltration applications, the infiltration rate decreased, the amount of residues was small, and Fe-based substrates adhered to each other.

Industrial Applicability

[0133] Since the Cu-based powder in the present invention contains Fe and Mn, if a Cu-based material made of the Cu-based powder in the present invention and an Fe-based material are used together for diffusion bonding or infiltration, Fe in the Fe-based material does not excessively diffuse to the Cu-based material side, and a Cu-based material excellent in diffusibility to the Fe-based material can be produced. Moreover, since the amount of Si dissolved in the Cu phase is small and it is difficult to form a SiO2 oxide film on the powder surface, it is a Cu-based powder that can suppress the inhibition of diffusion bonding, infiltration, and sintering by the SiO2 oxide film. Therefore, the present invention is an invention with high industrial applicability.

Claims

1. A Cu-based powder in which the Fe content is 1.5% by mass or more and 5.0% by mass or less, the Mn content is 0.3% by mass or more and 6.0% by mass or less, the Si content is 0.25% by mass or less, the O content is 0.25% by mass or more and 0.55% by mass or less, and the balance is Cu and inevitable impurities.

2. The Cu-based powder according to Claim 1, wherein the solid solution amount of Si in the phase containing 80% by mass or more of Cu is 0.2% by mass or less.

3. The Cu-based powder according to Claim 1 or 2, wherein the L value, which is the brightness of the powder, is 35 or more.

4. The Cu-based powder according to Claim 1 or 2, which has been subjected to rust prevention treatment and / or segregation prevention treatment.

5. The Cu-based powder according to Claim 1 or 2, which contains 0.1 out mass% or more and 1.0 out mass% or less of a lubricant.

6. The Cu-based powder according to Claim 1 or 2, which is for powder metallurgy.

7. The Cu-based powder according to Claim 1 or 2, which is for infiltration.

8. The Cu-based powder according to Claim 7, which contains 0.2% by mass or more and 3.0% by mass or less of Zn and 0.03 out mass% or more and 1.0 out mass% or less of Si powder.

9. A compacted body of the Cu-based powder according to Claim 1 or 2.

10. A sintered body of the Cu-based powder according to Claim 1 or 2.

11. A method for producing the Cu-based powder according to Claim 1 or 2.

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