Cu-based powder

Abstract

The present invention provides a Cu-based powder in which the content of Fe is from 1.5 mass% to 5.0 mass% (inclusive), the content of Mn is from 0.3 mass% to 6.0 mass% (inclusive), the content of Si is 0.25 mass% or less, the content of O is from 0.25 mass% to 0.55 mass% (inclusive), and the remainder is Cu and unavoidable impurities. The present invention provides a Cu-based powder which, when a Cu-based material and an Fe-based material are used together and are diffusion bonded or infiltrated, makes it possible to produce a Cu-based material having excellent diffusivity in the Fe-based material without excessive diffusion of Fe in the Fe-based material to the Cu-based material side, and in which it is difficult to form an SiO2 oxide film on the surface of the powder because the solid solution amount of Si in the Cu phase is small, and which can be used as a Cu-based material having excellent diffusivity in the Fe-based material. As a result, it is possible to suppress the inhibition of diffusion bonding, infiltration, and sintering due to the SiO2 oxide film.

Description

Technical Field

[0001] The present invention relates to a Cu-based powder. Specifically, it relates to a Cu-based powder containing Fe and Mn as follows: when a Cu-based material and a Fe-based material composed of the Cu-based powder of the present invention are used together and diffused or melt-infiltrated, Fe in the Fe-based material does not diffuse excessively to the Cu-based material side, and a Cu-based material having excellent diffusibility in the Fe-based material can be produced. In addition, since the amount of Si dissolved in the Cu phase is small, it is difficult to form SiO on the powder surface. 2 oxide film, so it can inhibit the SiO 2 The oxide film causes obstacles to diffusion bonding or melting and sintering. Background Art

[0002] Sometimes, Cu-based powder or a powder compact or sintered body made using Cu-based powder (hereinafter sometimes referred to as "Cu-based material") is used in combination with a powder compact or sintered body of Fe-based powder (hereinafter sometimes referred to as "Fe-based material", and in particular, the Fe-based material for infiltration is sometimes referred to as "Fe-based substrate") through diffusion bonding or infiltration.

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

[0004] As a method for preventing Fe of the Fe-based material from excessively diffusing into the Cu-based material and maintaining the diffusibility of the Cu-based material in the Fe-based material side, there is a method of causing the Cu-based powder to contain Fe or Mn.

[0005] Generally, when Fe or Mn is contained in a Cu-based powder, Fe is difficult to be dissolved in Cu and therefore is often added as an alloy, while Mn is often added as an alloy or a simple substance powder.

[0006] However, scrap steel containing Si may be used as a raw material when producing an alloy, or Si may be inevitably mixed from refractory materials such as a furnace body, and Si may be dissolved in a Cu phase of the produced Cu-based powder.

[0007] When Si is mixed into the alloy, SiO is formed on the powder surface. 2 The oxide film may change the melting point or strength, making diffusion bonding, infiltration, and sintering difficult, which may impair the characteristics of the Cu-based powder containing Fe and Mn.

[0008] Therefore, there is a demand for Cu-based powders containing Fe and Mn with an unexpectedly small amount of Si dissolved in the Cu phase.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application Publication No. 2008-101245. Summary of the invention

[0012] Problems to be solved by the invention

[0013] Patent Document 1 discloses an atomized powder of a Cu-based metal composed of Cu or a Cu alloy containing 400 ppm or less of impurity elements whose standard formation free energy of the lowest condensed phase oxide is lower than that of Zn oxide in a temperature range of 900°C or less.

[0014] The impurity removal method of Cu-based powder disclosed in Patent Document 1 is a method of melting the powder in the atmosphere and removing the impurity elements by floating them on the surface of the molten metal as oxide slag.

[0015] However, in the impurity removal method disclosed in Patent Document 1, when a large amount of scrap steel containing Si is melted or Si is supplied from a refractory such as a furnace body, Si may not be completely removed and may be dissolved in the Cu phase of the Cu-based powder.

[0016] In addition, although the reduction in sinterability can be suppressed by reducing the total content of impurity elements to 400 ppm or less, the sinterability of Cu-based powders containing Fe or Mn is inherently low. In powders having a total content of impurity elements at the same level as that of Patent Document 1, the reduction in sinterability needs to be further suppressed.

[0017] The inventors of the present invention have repeatedly conducted a large number of trials and experiments in order to solve the above-mentioned problems, and as a result, obtained the following findings and solved the above-mentioned technical problems: if a Cu-based material is made of a Cu-based powder having an Fe content of 1.5 mass% to 5.0 mass%, an Mn content of 0.3 mass% to 6.0 mass%, an Si content of 0.25 mass% to 0.55 mass%, and the remainder being Cu and inevitable impurities, when it is used together with a Fe-based material and these are diffusion-bonded or melt-infiltrated, the Fe of the Fe-based material will not excessively diffuse to the Cu-based material side, and the Cu-based material will be a Cu-based material with excellent diffusibility in the Fe-based material, and since the amount of Si in the Cu-based powder that is solid-dissolved in the Cu phase is small, it is difficult to form SiO on the powder surface. 2 oxide film, so it can inhibit the SiO 2 The oxide film causes obstacles to diffusion bonding or melting and sintering.

[0018] Technical solutions to solve problems

[0019] The above technical problems can be solved by the following present invention.

[0020] The present invention is a Cu-based powder, wherein 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 remainder is Cu and unavoidable impurities.

[0021] The present invention is also directed to the Cu-based powder, wherein the solid solution amount of Si in the phase containing 80 mass % or more of Cu is 0.2 mass % or less.

[0022] The present invention also provides the Cu-based powder having a powder brightness, that is, an L value of 35 or more.

[0023] Furthermore, the present invention is the Cu-based powder obtained by subjecting the powder to rust prevention treatment and / or segregation prevention treatment.

[0024] Furthermore, the present invention provides the Cu-based powder containing 0.1 out mass % or more and 1.0 out mass % or less of a lubricant.

[0025] Furthermore, the present invention provides the Cu-based powder used for powder metallurgy.

[0026] Furthermore, the present invention provides the Cu-based powder for use in infiltration.

[0027] The present invention is the above-mentioned Cu-based powder for infiltration, which contains 0.2 mass % to 3.0 mass % of Zn and 0.03 out mass % to 1.0 out mass % of Si powder.

[0028] Furthermore, the present invention is a powder compact of the Cu-based powder.

[0029] Furthermore, the present invention is a sintered body of the Cu-based powder.

[0030] Furthermore, the present invention is a method for producing the Cu-based powder.

[0031] Effects of the Invention

[0032] The present invention is a Cu-based powder comprising 1.5 mass % to 5.0 mass % Fe, 0.3 mass % to 6.0 mass % Mn, 0.25 mass % to 0.55 mass % O, and the remainder being Cu and unavoidable impurities.

[0033] When Mn is alloyed with Cu and Fe, Si mainly becomes Mn at the tapping temperature of about 1700K to 1750K.2 SiO 4 of liquid phase.

[0034] In addition, when Mn is used as a single substance powder or a partially alloyed powder, it mainly becomes Fe 2 SiO 4 of liquid phase.

[0035] Since the liquid phase is suspended in the Cu metal liquid, it is dispersed in the manufactured powder. However, due to the Mn in the powder 2 SiO 4 or Fe 2 SiO 4 The composite oxides such as Cu have low reactivity with Cu, Fe, and Mn below the liquid phase appearance temperature of Cu, and therefore are unlikely to affect the properties of the Cu-based powder.

[0036] Therefore, even if scrap steel containing Si is used as a raw material or a refractory such as a furnace containing Si is used for production, the amount of Si dissolved in the Cu-based powder in the Cu phase is reduced, making it difficult to form SiO on the powder surface. 2 Oxide film can suppress the decrease of reactivity on the outermost surface of the powder, so there is no need to remove Mn when making powder. 2 SiO 4 , Fe 2 SiO 4 And other composite oxides.

[0037] Furthermore, since Fe is added to the Cu-based powder in the present invention in an amount of 1.5 to 5.0 mass %, when the Cu-based material and the Fe-based material are used in combination, excessive diffusion of Fe in the Fe-based material to the Cu-based material side can be suppressed.

[0038] Furthermore, since a significant drop in the liquid phase appearance temperature due to the addition of Fe does not occur, even when used at high temperatures, problems such as melting and softening during use are unlikely to occur.

[0039] In addition, the strength of the powder can also be improved.

[0040] Furthermore, since Mn is easily dissolved in both Cu and Fe, it is possible to improve the diffusibility of the Cu-based material in the Fe-based material side.

[0041] Furthermore, the melting point and strength can be adjusted by the amount of Mn added. DETAILED DESCRIPTION

[0042] The Fe content of the Cu-based powder in the present invention is preferably 1.5% by mass to 5.0% by mass, and more preferably 2.0% by mass to 4.0% by mass.

[0043] When the Fe content is lower than 1.5 mass%, the solid solution amount (yield) in the Cu phase may be reduced due to the formation of composite oxides of Si and O. When the content exceeds 5.0 mass%, Fe may not be completely dissolved in Cu when the raw material is melted, resulting in component segregation.

[0044] The form of Fe is preferably an alloy powder with Cu.

[0045] The Mn content of the Cu-based powder in the present invention is preferably 0.3% by mass to 6.0% by mass, and more preferably 0.8% by mass to 5.0% by mass.

[0046] When the content is less than 0.3 mass %, when Mn is alloyed with Cu and Fe, the yield in the Cu phase may be reduced due to the formation of a composite oxide of Si and O.

[0047] If the content exceeds 6.0 mass %, when Mn is alloyed with Cu and Fe, the amount of Mn oxide generated increases and the viscosity of the molten metal increases, so that the nozzle may be clogged when the powder is produced by an atomization method.

[0048] In addition, when the content exceeds 6.0 mass%, when Mn is used as a single substance powder or a partially alloyed powder, it is difficult to obtain a uniform structure even when alloying with heat during use or when producing a partially alloyed powder, even if a short heat treatment is performed, so there is a possibility that economic efficiency will decrease.

[0049] The form of Mn in the Cu-based powder is not limited, and may be any of a simple powder, an alloy powder, and a partially alloyed powder.

[0050] This is because Mn easily dissolves in Cu or Fe, and therefore, even if mixed as a single substance powder, it can be easily alloyed with the heat used during sintering or infiltration.

[0051] The method for producing the simple substance powder of Mn is not particularly limited, and it may be produced by a known method such as a pulverization method.

[0052] Furthermore, when Mn is mixed as a single substance powder, segregation may occur, and it may be used for applications other than heating such as sintering or infiltration. Therefore, an alloy powder or partially alloyed powder with Cu and Fe is a more preferred form.

[0053] The Si contained in the Cu-based powder in the present invention is derived from unavoidable impurities, except when Si is intentionally added as Si powder.

[0054] Si, an inevitable impurity, usually bonds with O in the molten metal during the production of Cu-based powders to form SiO2 However, when the amount of Si-containing scrap steel melted is large or Si is supplied from refractory materials such as the furnace body, Si cannot be completely removed and is dissolved in the Cu phase of the Cu-based powder.

[0055] When Si is dissolved in the Cu phase of the Cu-based powder, SiO is formed on the powder surface. 2 Oxide film.

[0056] Because SiO 2 In an atmosphere containing hydrogen and having a dew point of about -30°C, the Cu-based powder cannot be reduced in an atmosphere such as a reducing atmosphere gas (hereinafter referred to as a "normal reducing atmosphere"). 2 When the film is oxidized, the reactivity of the outermost surface of the powder is significantly reduced, thereby reducing the diffusivity of atoms, electrical conductivity, thermal conductivity, ability to serve as a catalyst, etc.

[0057] The Si content is preferably 0.25 mass % or less, more preferably 0.008 mass % to 0.15 mass %.

[0058] When the Si content exceeds 0.25 mass%, the amount of Si dissolved in the Cu phase increases, and there is a possibility that SiO 2 The influence of the oxide film on the reactivity of the Cu-based powder increases.

[0059] The content of O in the present invention is preferably 0.25% by mass to 0.55% by mass, and more preferably 0.3% by mass to 0.5% by mass.

[0060] When the content of O is less than 0.25 mass%, Fe 2 SiO 4 or Mn 2 SiO 4 The amount of Si generated is small, and it is possible that Si is dissolved in the Cu phase.

[0061] In addition, when the O content exceeds 0.55 mass%, the yield in the Cu phase is reduced because of the excess O and oxidation of Fe or Mn, and the reactivity of the outermost surface of the Cu-based powder is reduced. Therefore, the atomic diffusivity, electrical conductivity, thermal conductivity, ability to act as a catalyst, etc. may be reduced.

[0062] The method for producing the alloy powder of the Cu-based powder in the present invention is not particularly limited, and a known atomization method such as a water atomization method, a gas atomization method, a centrifugal atomization method, etc. may be used.

[0063] The Cu-based powder of the present invention preferably has a powder brightness, that is, an L value of 35 or more.

[0064] The Cu-based powder in the present invention contains Fe 2 SiO4 or Mn 2 SiO 4 , so it is sometimes difficult to measure the oxygen amount, which is a general indicator of deterioration caused by the time-dependent change of the powder.

[0065] However, when the brightness of the powder, i.e., the L value, is 35 or more, even when it is difficult to measure the oxygen amount in the Cu phase, it can be inferred that the oxygen amount is low, and the reduction in reactivity caused by oxidation of the outermost surface of the Cu-based powder can be suppressed. Therefore, the reduction in atomic diffusivity, electrical conductivity, thermal conductivity, ability to act as a catalyst, etc. can be suppressed.

[0066] The Cu-based powder of the present invention, that is, a part or the whole of the powder constituting the Cu-based powder, may be subjected to rust prevention treatment and / or segregation prevention treatment.

[0067] Segregation that may occur in the Cu-based powder includes precipitation segregation, which occurs due to differences in fluidity of various powders that are mixed.

[0068] The flowability of the powder may change due to surface oxidation of the powder, and even if segregation does not occur immediately after production, segregation may become significant in a relatively short period of time depending on the storage environment.

[0069] When the Cu-based powder segregates, the average particle size tends to vary, which may cause a variation in the amount of powder supplied to the die or a variation in the sintered density.

[0070] By subjecting a part or all of the powder constituting the Cu-based powder to an anti-segregation treatment, it is possible to suppress variations in the average particle size.

[0071] The anti-segregation treatment is not particularly limited, and examples thereof include surface modification treatments that reduce fluidity such as reducing the specific surface area by granulating the powder or making the powder containing oxides porous by reducing the powder, or addition of various functional groups by chemical reaction or physical adsorption with organic compounds such as adding a binder.

[0072] Furthermore, if rust-proofing is performed, not only segregation can be suppressed, but also a decrease in reactivity due to oxidation of the outermost surface of the powder can be suppressed, thereby suppressing a decrease in atomic diffusivity, electrical conductivity, thermal conductivity, catalytic performance, and the like.

[0073] The rust inhibitor is not particularly limited, but is preferably an organic compound containing one or more elements coordinated to Cu per molecule, and more preferably an organic compound having 3 to 30 carbon atoms.

[0074] Examples of the rust inhibitor or the anti-segregation agent include benzotriazole and machine oil.

[0075] A lubricant may be added to the Cu-based powder of the present invention. When a lubricant is added, the Cu-based powder can be easily molded using a mold or the like.

[0076] The content of the lubricant is preferably 0.1 out mass % to 1.0 out mass %, more preferably 0.2 out mass % to 0.8 out mass %.

[0077] When the amount is less than 0.1 out mass %, the effect of improving lubricity is low, and when the amount added exceeds 1.0 out mass %, there is a possibility that formability may deteriorate.

[0078] The lubricant is not particularly limited, but is preferably a metal soap such as zinc stearate or an EBS-based wax.

[0079] The Cu-based powder of the present invention can be used for powder metallurgy.

[0080] Because 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 made into a multilayer structure and diffusion-bonded, the Fe of the Fe-based material is difficult to excessively diffuse on the Cu-based material side, and the diffusibility of the Cu-based material in the Fe-based material side can be improved.

[0081] In addition, since the amount of Si dissolved in the Cu phase of the Cu-based powder is small, it is difficult to form SiO on the powder surface. 2 Therefore, the powder compact of the Cu-based powder can be easily sintered in a normal sintering atmosphere without being affected by the SiO 2 Diffusion barrier caused by oxide film.

[0082] In addition, the strength of the sintered body can be improved by forming a solid solution of Fe or Mn in the Cu phase.

[0083] Furthermore, by precipitating Fe dissolved in the Cu phase by heat treatment after sintering, the strength of the sintered body can be improved.

[0084] The Cu-based powder of the present invention can be used for infiltration.

[0085] Since the Cu-based powder in the present invention contains Fe and Mn, Fe of the Fe-based substrate is unlikely to diffuse excessively into the Cu-based molten infiltration material, and the diffusibility of the Cu-based molten infiltration material into the Fe-based substrate can be improved.

[0086] In addition, since the amount of Si in the Cu-based powder is small, it is difficult to form SiO on the powder surface. 2 Therefore, when the powder compact of Cu-based powder is melt-infiltrated into Fe-based substrate under normal melt-infiltrating atmosphere, it is difficult to generate the oxide film composed of SiO 2 The oxide film causes a decrease in wettability.

[0087] Furthermore, since Fe or Mn is dissolved in the Cu phase, the so-called etching phenomenon, in which Fe in the Fe-based substrate melts into the contacting Cu-based infiltration material to roughen or form pits on the surface of the Fe-based substrate, is less likely to occur.

[0088] The Cu-based powder of the present invention contains Fe 2 SiO 4 or Mn 2 SiO 4 After infiltration, residue remains on the surface of the Fe-based substrate (hereinafter, this residue is referred to as "residue").

[0089] When the residue is generated, when a plurality of Fe-based substrates and a Cu-based infiltration material are stacked and infiltration is performed in order to increase the production volume of sintered parts per unit time, adhesion of the Fe-based substrates to each other can be prevented.

[0090] The Fe generated when the Cu-based powder of the present invention is produced 2 SiO 4 or Mn 2 SiO 4 Since the liquid phase of Cu is suspended in the Cu molten metal, it is dispersed in the manufactured powder. Therefore, the generation of residue is less likely to vary, and the residue can be generated stably.

[0091] When the Cu-based powder of the present invention is used as an infiltration material, Zn may be contained.

[0092] The addition of Zn has the effect of lowering the melting point of the infiltration material or improving the wettability between the infiltration material and the substrate to increase the infiltration rate.

[0093] The Zn content is preferably 0.2 to 3.0 mass%, more preferably 0.5 to 2.0 mass%.

[0094] When the Zn content is less than 0.2 mass %, no improvement in wettability is observed. When the content exceeds 3.0 mass %, the evaporation amount of Zn during the infiltration process may increase, the yield of the infiltration material may deteriorate, and the infiltration rate may decrease.

[0095] In addition, the evaporated Zn may contaminate the sintering furnace.

[0096] The form of Zn is not limited and may be any of a simple powder, an alloy powder, and a partially alloyed powder, but is preferably an alloy powder because a simple powder of Zn is more likely to become a gas phase than an alloy powder.

[0097] The method for producing the Zn simple substance powder is not particularly limited, and the powder may be produced by a known method such as a pulverization method or an atomization method.

[0098] The Cu-based powder for infiltration in the present invention may contain Si powder.

[0099] The Si powder is different from Si mixed in as inevitable impurities when producing the Cu-based powder, and is made by adding Si as a single substance powder to the Cu-based powder containing Fe and Mn.

[0100] Since Si powder is easily oxidized during the temperature rise process in the melt infiltration, it is difficult to form SiO on the surface of Cu-based powder. 2 Since there is no oxide film, the basic infiltration characteristics such as the reduction of wettability between the Cu-based powder and the Fe-based substrate are not affected.

[0101] When Si powder is added to the Cu-based powder for infiltration, it becomes a residual component and reduces the infiltration rate. Therefore, it is possible to finely adjust the infiltration rate or make up for the deficiency of the residual component.

[0102] The Si powder is preferably added in an amount of 0.03 out mass % to 1.0 out mass %, and more preferably added in an amount of 0.04 out mass % to 0.8 out mass %.

[0103] When the Si powder content is less than 0.03out mass%, no decrease in the infiltration rate or increase in the residual component is observed. In addition, when the content exceeds 1.0out mass%, segregation of the residual component may occur due to an excessive decrease in the infiltration rate, an excessive increase in the residual component, and segregation of the Si powder.

[0104] The method for producing Si powder is not particularly limited, and the Si powder may be produced by a known method such as a pulverization method.

[0105] The average particle size of each powder constituting the Cu-based powder in the present invention is preferably 1 μm to 300 μm.

[0106] This is because when the particle size exceeds 300 μm, uniform mixing may not be achieved and component segregation may occur, and when the particle size is less than 1 μm, the handling property may deteriorate and the powder may become expensive, thereby reducing economic efficiency.

[0107] The Cu-based powder in the present invention can be produced into a powder compact by a known method.

[0108] The Cu-based powder for infiltration in the present invention can be used to prepare an infiltration material by a known method such as powder press molding.

[0109] [Example]

[0110] Although the Examples and Comparative Examples of the present invention have been described, the present invention is not limited thereto.

[0111] <Cu-based powder>

[0112] (Manufacturing of Cu-based powders with Mn added as alloy) ... A

[0113] Cu ingots, Fe ingots, Fe—Mn ingots, and Si ingots were weighed according to the compositions listed in Table 1 and melted in a high-frequency melting furnace.

[0114] The Cu-based powder was prepared by sieving the powder produced by the water atomization method in which the alloy component in a molten state was brought into contact with high-pressure water of about 15 MPa while falling to be rapidly solidified, to 200 mesh or less.

[0115] (Production of Cu-based powder to which Mn is added as a single substance powder) ... B

[0116] Cu ingots, Fe ingots, and Si ingots were weighed according to the compositions listed in Table 1 and melted in a high-frequency melting furnace.

[0117] The Cu-Fe-Si alloy powder was prepared by sieving the powder produced by the water atomization method to 200 mesh or less. In the water atomization method, the alloy component in a molten state was brought into contact with high-pressure water of about 15 MPa while falling to be rapidly solidified.

[0118] The Cu-based powder was prepared by mixing the Cu-Fe-Si alloy powder prepared according to the composition shown in Table 1 and Mn powder prepared by pulverizing a Mn ingot and then sieving it to 200 mesh or less using a rock mixer.

[0119] The powders of Comparative Examples 2 and 4 to 7 were produced by adjusting the deoxidation operation of the molten metal so that the O content was lower than the range of the present invention.

[0120] The powder of Comparative Example 3 was produced by adjusting the deoxidation operation of the molten metal so that O was outside the range of the present invention.

[0121] (Inspection of Cu-based powder)

[0122] The Cu, Fe, Mn, Si and Zn contained in the Cu-based powders A, B or C to E described later were quantitatively analyzed using an ICP emission spectrometer iCAP7600 (manufactured by Thermo Fisher Scientific) to check whether each element was within the numerical range of the present invention.

[0123] When the amount was within the numerical range of the present invention, O was quantitatively analyzed using an oxygen analyzer EMGA-920 (manufactured by Horiba, Ltd.), and it was confirmed that the amount of all elements in the Cu-based powder of the example was within the numerical range of the present invention.

[0124] The L value was measured using a spectrocolorimeter SE6000 (manufactured by Nippon Denshoku Industries, Ltd.).

[0125] <Measurement of the amount of Si dissolved in the Cu phase>

[0126] 1 g of Cu-based powder of A or B was embedded in cold resin and ground with 0.3 μm abrasive to obtain a sample. The sample was elementally mapped at 400 times using an energy dispersive X-ray spectrometer (EDS) attached to a field emission scanning electron microscope FE-SEM (manufactured by JEOL Ltd.). Ten particles of Cu phase containing Si were selected from the field of view and point analysis or surface analysis was performed to quantify the Si in the Cu phase.

[0127] As a result of quantitative analysis, a portion containing Fe or Mn and O at the same position as Si and having a Cu amount of less than 80 mass % was determined to be an oxide phase of Fe or Mn and Si (not a Cu phase), and the Si amount in the other Cu phases was confirmed to be less than 0.2 mass % (detection limit 0.01 mass %) on an average of 10 particles.

[0128] <Application of Cu-based powder in powder metallurgy>(Manufacturing of Cu-based powder for powder metallurgy)…C

[0129] 0.3 out mass % of zinc stearate was added as a lubricant to the Cu-based powder of A or B, and the mixture was mixed with a rock mixer to prepare a Cu-based powder for powder metallurgy.

[0130] (Sinterability of Cu-based powder)

[0131] The powder metallurgy of C is formed into a ring shape with an outer diameter of 14 mm×inner diameter of 7 mm×height of 8 mm and a molding density of 6.3 g / cm 3 The powder was compacted by a method of , and sintered at 1273 K for 30 minutes in a hydrogen atmosphere to obtain each sintered body. The density change of each sintered body before and after sintering was calculated according to the following (Formula 1).

[0132] (Formula 1) (Sintering density - Forming density) / Forming density × 100

[0133] <Application of Cu-based powder in melt infiltration>

[0134] (Manufacturing of Cu-based powder for infiltration with Mn added as alloy or single powder)

[0135] 0.5 out mass % of zinc stearate was added as a lubricant to the Cu-based powder of A or B, and the mixture was mixed with a rock mixer to prepare a Cu-based powder for infiltration.

[0136] (Manufacturing of Cu-based powder for infiltration with Mn as a single substance powder and Zn as an alloy)

[0137] Cu ingots, Fe ingots, Zn ingots, and Si ingots were weighed according to the compositions shown in Table 1 and melted in a high-frequency melting furnace.

[0138] The Cu-Fe-Zn-Si alloy powder is prepared by sieving the powder prepared by the water atomization method to less than 200 meshes. In the water atomization method, the alloy component in a molten state is brought into contact with high-pressure water of about 15 MPa while falling to be rapidly solidified.

[0139] The Cu-based powder was prepared by mixing the Cu-Fe-Zn-Si alloy powder prepared according to the composition shown in Table 1 and Mn powder prepared by pulverizing a Mn ingot and then sieving it to 200 mesh or less using a rock mixer.

[0140] After inspecting the Cu-based powder as described above and confirming that each element is within the numerical range of the present invention, Cu-based powder, 0.05out mass % of Si powder produced by crushing Si ingots and sieving them to less than 200 mesh, and 0.5out mass % of zinc stearate as a lubricant are added according to the composition described in Table 1, and mixed using a rock mixer to produce Cu-based powder for infiltration.

[0141] (Wetting properties of Cu-based powder)

[0142] Electrolytic Cu powder, graphite powder and atomized Fe powder were mixed so that Cu was 1.5 mass %, C was 1.0 mass % and the balance was Fe. 13.7 g of the mixed powder to which 0.8 mass % of zinc stearate was added was formed into a square column 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 The two Fe-based substrates are formed by compacting the powder.

[0143] The Cu-based powder for infiltration in an amount of 80% by volume relative to the pores of the prepared Fe-based substrate was powder pressed into a thin plate of 12 mm in width×30 mm in length×1 mm in thickness to prepare two infiltration materials.

[0144] A melt infiltration material is placed on the Fe-based substrate, and another Fe-based substrate and a melt infiltration material are placed thereon, and melt infiltration is performed by a one-step melt infiltration method.

[0145] As the infiltration conditions, the lubricant in the infiltration material was dewaxed by heating at 823 K for 30 minutes, and then heated at 1403 K for 30 minutes.

[0146] The atmosphere in the sintering furnace was set to a mixed gas atmosphere of hydrogen:nitrogen at a ratio of 3:1.

[0147] The case where the residue was generated uniformly and easily peeled off was judged as ○, and the case where no residue was generated, the generated amount was excessive, the generated amount was uneven, or the Fe-based substrates adhered to each other was judged as ×.

[0148] For the base material in the lower stage, the infiltration rate was calculated based on the following formula 2 (Mathematical formula 1).

[0149] [Mathematical formula 1]

[0150]

[0151] W: Weight of the melt after removing the residue (g)

[0152] Ws: Weight of base material compact (g)

[0153] Q: Lubricant mixed in base material (%)

[0154] Wi: Weight of melt-infiltrated material (g)

[0155] L: Lubricant mixed in the molten material (%)

[0156] Table 1 shows the compositions and results of each example and comparative example.

[0157] [Table 1]

[0158]

[0159] As shown in Examples 1 to 8, even if the Cu-based powder of the present invention contains Si, as long as the amounts of all elements in the Cu-based powder are within the range of the present invention, the amount of Si dissolved in the Cu phase is small, and the formation of Cu by SiO can be suppressed. 2 The oxide film reduces the reactivity of the outermost surface of the Cu-based powder.

[0160] In addition, it is shown that the Cu-based powder for powder metallurgy of the present invention has excellent sinterability because the amount of Si dissolved in the Cu phase is small.

[0161] In addition, it is shown that the infiltration material composed of the Cu-based powder for infiltration of the present invention has a high infiltration rate because the amount of Si dissolved in the Cu phase is small, and the Fe 2 SiO 4 or Mn 2 SiO 4 Since the residue is stably generated on the surface of the base material after the infiltration, the productivity is also excellent.

[0162] As for the Cu-based powder of Comparative Example 1, since the Si content exceeds 0.25 mass% and the solid solution amount of Si in the Cu phase exceeds 0.2 mass%, the sintering property is lower than that of Example 3 for powder metallurgy applications, the infiltration rate is also reduced for infiltration applications, and the amount of residue generated is large and difficult to remove.

[0163] In the Cu-based powder of Comparative Example 2, although the solid solution amount of Si in the Cu phase is less than 0.2 mass %, O is less than 0.25 mass %, so Fe is higher than that of Example 3 with a similar composition. 2 SiO 4 or Mn 2 SiO 4 The amount of generated is small, the sintering property is low in powder metallurgy applications, the infiltration rate is also reduced in infiltration applications, the amount of residue is small, and the Fe-based substrates adhere to each other.

[0164] Regarding the Cu-based powder of Comparative Example 3, although the solid solution amount of Si in the Cu phase is less than 0.2 mass%, O exceeds 0.55 mass% and the L value is also less than 35. Therefore, in terms of powder metallurgy applications, the sintered body expands, and in terms of infiltration applications, the wettability decreases and the infiltration rate decreases.

[0165] Furthermore, since Fe or Mn is oxidized, a large amount of raw materials is required to achieve a desired yield, thereby reducing economic efficiency.

[0166] In the Cu-based powder of Comparative Example 4, since O is less than 0.25 mass %, Fe 2 SiO 4 or Mn 2 SiO 4 The amount of generated is small, and the solid solution amount of Si in the Cu phase exceeds 0.2 mass %, so the sintering property is low in powder metallurgy applications, and the infiltration rate is also reduced in infiltration applications, and adhesion of Fe-based substrates to each other and adhesion of residues are observed.

[0167] In the Cu-based powder of Comparative Example 5, although the solid solution amount of Si in the Cu phase is less than 0.2 mass %, O is less than 0.25 mass %, so Fe is higher than that of Example 8 with a similar composition. 2 SiO 4 or Mn 2 SiO 4 The amount of generated is small, so in terms of infiltration application, the infiltration rate is reduced, the amount of residue is small, and the Fe-based substrates adhere to each other.

[0168] The Cu-based powders of Comparative Examples 6 and 7 have a relatively low Si content of 0.03 mass % and a small amount of Si dissolved in the Cu phase. Therefore, the density change is positive in terms of powder metallurgy applications.

[0169] However, since O is less than 0.25 mass %, Fe 2 SiO 4 or Mn 2 SiO 4 The amount of generated is small, and therefore, compared with Examples 1 and 2, the sintering property is low in powder metallurgy applications, the infiltration rate is reduced in infiltration applications, the amount of residue is small, and the Fe-based substrates adhere to each other.

[0170] Industrial Applicability

[0171] The Cu-based powder of the present invention contains Fe and Mn. Therefore, when the Cu-based material and the Fe-based material composed of the Cu-based powder of the present invention are used together to diffusely connect or melt-infiltrate them, the Fe of the Fe-based material will not excessively diffuse to the Cu-based material side, and the Cu-based material with excellent diffusibility in the Fe-based material can be produced. In addition, since the amount of Si dissolved in the Cu phase is small, it is difficult to form SiO on the powder surface. 2 The oxide film is therefore able to inhibit the SiO 2 Cu-based powders that have an oxide film that hinders diffusion bonding, infiltration, and sintering.

[0172] Therefore, the present invention has high industrial applicability.

Claims

1. A Cu-based powder, characterized in that: 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 remainder is Cu and unavoidable impurities.

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

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

4. The Cu-based powder according to claim 1 or 2, wherein The Cu-based powder is subjected to rust prevention treatment and / or segregation prevention treatment.

5. The Cu-based powder according to claim 1 or 2, wherein The Cu-based powder 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, wherein The Cu series powder is used for powder metallurgy.

7. The Cu-based powder according to claim 1 or 2, wherein The Cu-based powder is used for melt infiltration.

8. The Cu-based powder according to claim 7, wherein The Cu-based powder contains 0.2 mass % to 3.0 mass % both inclusive of Zn and 0.03 out mass % to 1.0 out mass % both inclusive of Si powder.

9. A powder compact 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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