Metal resin composite powder and method for producing non-sintered curable metal molding

Abstract

To provide a method for producing non-sintered curable metal molding in order to overcome a problem that metal products of various shapes are produced by punching, bending, cutting, etc. from flat plates or rod-shaped metal ingots using appropriate processing equipment, or by powder metallurgy technology using general metal powder, which involves high-pressure compression molding and sintering at high temperatures using pressure molding machines with large pressure forces and large-scale sintering furnaces, this requires particularly excessive capital investment and the use of high heat energy during sintering, and remains outside the scope of the carbon reduction initiative.SOLUTION: There are provided a material composition and its producing method in which a metal powder that has been surface-treated with a compound having multiple reactive groups in its molecules that chemically bond to inorganic and organic materials and a thermosetting resin that has a B-stage (semi-cured state) in which it exhibits a certain plastic state midway through the curing reaction are first combined together and then crushed and classified to produce a metal-resin composite powder, which is then low-pressure compressed again in the B-stage region to produce a heat-cured molded product with very little energy.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a metal-resin composite powder used for hardening and molding metal powder without a sintering process, a thermosetting metal molded body obtained through a hot low-pressure compression molding and a thermosetting process, and a method for producing the same. [Background technology]

[0002] Conventionally, metal products with shapes that meet required characteristics are formed by punching, bending, cutting, etc. from flat plates or rod-shaped metal ingots using processing equipment appropriate for the process.

[0003] On the other hand, products that require mass production are manufactured using powder metallurgy, in which metal powder is compressed under high pressure using a mold that corresponds to the shape, and then sintered in a furnace where the temperature and atmosphere are controlled. [Prior art documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-150648 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-140535 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the pressure applied in the compression molding process used in the powder metallurgy manufacturing process as shown in Patent Document 1 is usually 5 to 9 ton / cm. 2 High pressure is required, and the same Scholar is not chemically bonded, and the next step is to Scholar To increase the bonding strength, a sintering process is required in which a temperature profile of heating, constant temperature and cooling is controlled in a furnace at 500 to 1200°C for approximately 4 to 6 hours, but this poses challenges in terms of energy consumption and decarbonization. Furthermore, the strength of the molded product is low and it may break when transferred to the sintering furnace in the next process, so care must be taken when handling it.

[0006] Furthermore, metal powder injection molding (MIM) is being carried out, as shown in Patent Document 2, in which multiple organic binders and metal powder are made into composite pellets, which are then injection molded and then subjected to a sintering process similar to that of Patent Document 1. However, this method requires a debinding process in which the binders added to achieve the fluidity and shape formation essential during injection molding are decomposed and removed before the sintering process; the temperature must be raised in stages from room temperature to around 600°C in an inert atmosphere, depending on the decomposition temperature of the multiple binders contained, and then the sintering furnace must be heated to 1000°C or higher. Therefore, there are more issues than those in Reference 1, including the equipment and process management aspects in the debinding and sintering processes.

[0007] The object of this invention is to provide a metal-resin composite powder for compression molding, a thermosetting metal molded body, and a method for manufacturing the same, in which coarse particles above a specified particle size have been removed to produce a thermosetting molded body that is optimal for use as a metal product with a finely textured shape and a smooth surface, by using metal powder equivalent to that used in conventional powder metallurgy and through low-pressure molding and low-temperature hardening processes, without the need for special equipment or high energy consumption, and which can be completed at a significantly lower temperature and in a shorter number of steps than powder metallurgy and MIM, thereby making a significant contribution to energy costs and environmental issues. [Means for solving the problem]

[0008] To achieve the above objectives, the material composition of the present invention is formed by combining a metal powder that has been surface-treated with a compound having multiple reactive groups in its molecules that chemically bond to inorganic and organic materials, and a thermosetting resin that has a B-stage (semi-cured state) that exhibits a certain plastic state during the curing reaction.

[0009] Metal powders include iron, aluminum, tungsten, stainless steel, titanium, zinc, tin, and copper. 、 It may contain one or more metals selected from lead, magnesium, chromium, cobalt, nickel, zirconium, molybdenum, silver, neodymium, platinum, gold, and samarium. The above metal powder is granulated by reduction, electrolysis, atomization, etc. depending on the purpose of use, and the coarse grain size is adjusted to a predetermined particle size distribution. powderFine particles are removed, and the maximum particle size is generally controlled to be 105 to 212 μm.

[0010] The metal powder of the present invention has a coarse particle size of 100 μm or more, preferably 90 μm or more, in order to improve the bonding strength of the thermosetting metal compact. powder The metal is then classified and removed, and the surface is treated with a surface treatment agent that has multiple different reactive groups in its molecule to improve the bonding strength with the thermosetting resin that is compounded to form the thermosetting metal molded body.

[0011] The surface-treated metal powder is given high fluidity during molding, which increases shape reproducibility and solidification after molding, resulting in a high-density structure. To achieve this, a resin component consisting primarily of epoxy resin or polyester resin, mixed with amine-based or isocyanate-based hardeners and additives, is added at a ratio of 20 wt% or less, and the kneaded composite material is plasticized at a certain heating temperature to form a paste, which is then crushed and classified to produce a metal-resin composite powder.

[0012] Alternatively, a slurry of surface-treated metal powder, epoxy resin or polyester resin as the main components, amine or isocyanate curing agents and additives is added, and a solvent such as methyl ethyl ketone, which vaporizes at a low temperature of around 100°C, is mixed uniformly and flattened using a doctor blade or the like, and the solvent is evaporated to obtain a plate-shaped solidified material, which is then crushed and classified to produce a metal-resin composite powder.

[0013] The plasticized paste kneaded composite material or the solvent mixed composite material is crushed and then coarsely crushed. powder The cut metal-resin composite powder is placed in a mold space consisting of upper and lower punches and dies processed according to the product shape, and is then molded under low pressure at or above the B-stage temperature, after which it is cooled.

[0014] The equipment used for pressure molding is equipped with a mechanism for controlling the heating and cooling of the mold. The mold containing the metal-resin composite powder is installed, and the temperature is controlled between the upper and lower limits of the heat distortion temperature at which the thermosetting resin becomes plastic (B-stage region). Up to the areaIt is characterized by being equipped with a mechanism that allows the solidified molded body to be released from the mold after cooling.

[0015] The upper limit of the temperature at which pressure molding can be performed is 10°C above the heat distortion temperature. Below Upper, the region below 30°C of the curing start temperature, the lower limit temperature at which demolding occurs is 20°C above the heat distortion temperature Below The lower region is preferably determined depending on the shape and dimensions of the molded product to be formed in the mold and productivity.

[0016] In general powder metallurgy compression molding, in order to increase the final sintering strength, the usual sintering rate is 5 to 9 ton / cm for iron-based materials. 2 In contrast, the process of the present invention requires a high pressure of 2 to 3 tons / cm. 2 This eliminates the need to use a large press or to worry about damaging the mold.

[0017] During heat compression molding, the thermosetting resin first flows into a fluid state and fills the spaces between the metal particles in the mold. As the resin cools from the pressurized temperature range, it becomes a binder between the metal particles and is then released from the compression molding mold as a solidified molded body that maintains its molded shape.

[0018] In general powder metallurgy molded products, including MIM, sintering is carried out over a temperature profile ranging from 500°C to 1200°C for 4 to 6 hours to chemically bond the metal after molding depending on the metal composition. In this invention, however, the solidified molded product is removed from the mold in a solidified state where the resin component has acted as an adhesive, and is then placed in a thermostatic bath heated to a hardening temperature of around 200°C for 10 to 30 minutes until the resin component has completely hardened. After this, the product is removed from the bath and cooled to obtain the desired hardened molded product.

[0019] The thermostatic chamber can be used to load all the compacts into a batch-type general-purpose drying device after molding, which significantly reduces the equipment cost, installation area, and energy input compared to conventional powder metallurgy molding, and also eliminates the need for temperature profile setting and atmosphere control in the sintering furnace.

[0020] The surface of the resulting molded product after the curing reaction has improved smoothness due to the curable resin used as a binder between the metal powder particles, forming a smoother surface than the surface of a molded product obtained by ordinary powder metallurgy molding.

[0021] In the present invention, the temperature range is 60 to 130°C, and the curable resin is in a plasticized B-stage state and compressed into a compression mold at a rate of 2 to 3 tons / cm per square centimeter. 2 The mold is then released after the resin is cooled and solidified to maintain its shape, and finally the surface is hardened at 160-220°C for 10-30 minutes to achieve a smooth surface and sufficient strength. heat curing A metal compact is obtained. [Effects of the Invention]

[0022] In the present invention, a metal-resin composite material is obtained by mixing and kneading a metal powder that has been surface-treated with a coupling agent having two or more different reactive groups in the molecule with a thermosetting resin in a plasticized state by heating above a certain temperature, or a sheet-shaped metal-resin composite material is obtained by dispersing and mixing a mixture of a metal powder and a thermosetting resin in a slurry state using a solvent, and then evaporating and removing the solvent from the sheet-shaped metal-resin composite material. The resulting metal-resin composite powder is then crushed and classified and placed in a mold, which is then subjected to heat compression molding and a cooling control mechanism. pressure Using compression molding equipment, pressure molding is performed in the B-stage (plasticized state) area and demolding is performed in the cooling area, and then a short-term hardening process is performed in a constant temperature bath at around 200°C, resulting in a smooth surface. fever Hardened metal moldings can be produced using simple equipment and process management, making it possible to significantly reduce energy costs and achieve carbon-free manufacturing. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a flowchart of a method for producing a metal-resin composite powder according to an embodiment of the present invention. [Figure 2] 1 is a flowchart of a method for producing a thermosetting metal molded product obtained using a metal-resin composite powder according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, this embodiment About The following description will be given with reference to the drawings, in which: Fig. 1 is a flowchart showing a manufacturing method according to the present embodiment up to obtaining a thermosetting metal molded body. This flowchart shows the process of classifying metal powders used in powder metallurgy to a predetermined particle size distribution as a pre-process, then surface treating the metal powders with a coupling agent, a compound having multiple reactive groups in its molecule, compounding the metal powders with a thermosetting resin, and crushing them into a coarse powder. powder This shows the manufacturing process for metal-resin composite powder, which is used as molding powder after cutting. FIG. 2 is a flowchart showing a manufacturing method in which the metal-resin composite powder is used in a post-process by heat compression molding in a B-stage (plasticized state) region and demolding in a cooling region to produce a final hardened metal molded body.

[0025] First, the particle size distribution of metal powders used in ordinary powder metallurgy is adjusted to a coarse particle size above a certain particle size using a vibrating sieve or an air classifier in order to improve the strength and surface smoothness of the hardened compact. powder Cut. Coarse powder The classification point is selected based on the mechanical strength and surface smoothness required for the cured molded product, but a point of approximately 90 μm is desirable.

[0026] Metal powder is contact In order to enhance the bond with the B-stage (semi-cured) thermosetting resin used as an adhesive, the surface is treated with a coupling agent, which is a compound with multiple reactive groups in its molecules that chemically bond to both inorganic and organic materials.

[0027] In the surface treatment process using a coupling agent, a liquid of the coupling agent diluted with alcohol or water is poured into a mixing and stirring device and an appropriate amount is dropped onto the metal powder in a stirred state. The alcohol and water are evaporated by the shear heat generated during the mixing and stirring process, and after drying is complete, the surface-treated metal powder is discharged and recovered from the mixing and stirring device.

[0028] Another surface treatment is that using graphene oxide, a nanocarbon material dispersed in an aqueous medium, in which an appropriate amount of graphene oxide solution is added to metal powder that has been placed in water and stirred and mixed, and the mixture is stirred and mixed for a certain period of time.The mixture is then decanted and washed using filter paper or the like to remove excess graphene oxide, and the mixture is then dried at around 110°C to recover the surface-treated metal powder.

[0029] In order to improve the fluidity within the mold during heat compression molding, to improve the bonding strength between the powders after hardening, and to create a high-density molded body structure, surface-treated metal powder is combined with a thermosetting resin at a composition ratio of 20 wt% or less.

[0030] The process of compounding thermosetting resin and metal powder involves heating in the B-stage temperature range to plasticize the thermosetting resin into a paste state, and then uniformly mixing the resin with two rolls or a kneader. training In addition to the above method, a method is also possible in which a thermosetting resin liquefied using a solvent and a metal powder are uniformly stirred and mixed to form a slurry, which is then flattened with a doctor blade or the like, and the solvent components are then evaporated off to form a plate-like solidified product.

[0031] The mixed composition of metal powder and thermosetting resin is compounded in a state where the thermosetting resin is interposed on the surface of the metal powder and binds the metal powder together using a dry method of kneading a heated paste or a wet method using a solvent, and in order to make the powder for compression molding in a state where the thermosetting resin covers the surface of the metal powder, it is crushed in the next process and then crushed into coarse particles of about 90 μm or more using a vibrating sieve, etc. powder Cut.

[0032] Compression molding uses a die and upper and lower punches in the same way as regular powder metallurgy manufacturing, but it is carried out in a press machine equipped with equipment to control the temperature rise and cooling of the mold. It is carried out between the temperature above the plastic state (B stage) of the thermosetting resin and the temperature below the temperature at which the hardening reaction begins. After being pressed in the B stage region, it is cooled, and the resin is released from the mold in the region below the B stage temperature. Fever The device is characterized by being equipped with a mechanism that allows the hardened metal molding to be released from the mold.

[0033] Pressurization is carried out between the heat distortion temperature at which the thermosetting resin becomes plastic and the temperature at which the curing reaction begins to proceed, but it is preferable to do so at a temperature 10°C above the heat distortion temperature and 30°C below the curing temperature. thermoset metal The temperature is set according to the dimensions and shape of the molded product and productivity.

[0034] The molding pressure is required to plasticize the thermosetting resin and give it the fluidity to act as a binder between the metal powders, and it can be done at a significantly lower pressure, about one-quarter to one-third that of conventional powder metallurgy.

[0035] After pressure molding, the cooling mechanism is activated to lower the temperature of the die and upper and lower punches to below the heat distortion temperature of the thermosetting resin, preferably below 20°C, and then the mold is opened. thermoset metal The molded body is released from the mold and collected.

[0036] After compression molding, the molded body is removed from the mold and left to stand for 10 to 30 minutes in a standard thermostatic chamber set at a heat-hardening temperature of around 200°C to obtain the final heat-hardened metal molded body. The surface of the obtained hardened metal molding is formed by the thermosetting resin in a plasticized state during pressure molding, forming a so-called skin layer. powder The surface smoothness is also far superior to that of powder metallurgy compacts.

[0037] (Major Effects Obtained by This Embodiment) In this embodiment, in order to form metal products by low-pressure compression powder molding, metal powder that has been surface-treated using a coupling agent that has two or more different reactive groups in its molecule is combined with a specific temperature range (B stage). plasticity The metal powder is then heated and pressed into a mold, where it is then molded under low pressure. Hard The surface obtained by the curing process is smooth. heat Hardened metal moldings are possible without the use of special equipment or high energy requirements. Compared to products made by conventional powder metallurgy processing and metal injection molding (NIM), low-temperature hardening is possible without the sintering process, which contributes greatly to significant energy cost reductions and the resolution of the decarbonization issue.We can also provide a material composition and manufacturing method that allows for the production of hardened metal compacts with fine irregularities and smooth surfaces.

[0038] Surface treatment of metal powder using a coupling agent with two or more different reactive groups in its molecule can be carried out by a simple process in which the metal powder is placed in a mixing and stirring device, and an appropriate amount of coupling agent diluted with alcohol or an alcohol aqueous solution is dropped onto the mixed metal powder, and the solvent is removed by shear heat during stirring and mixing; or by adding an appropriate amount of graphene oxide solution to the mixed metal powder placed in water, and then filtering and recovering the powder. This easily results in a strong bond between the metal powder and the thermosetting resin.

[0039] The surface-treated metal powder is mixed with a paste in a plasticized state of a thermosetting resin with a B stage. training The composite is made in advance by wet mixing sheeting using a solvent or the like, and then crushed into a coarse powder. powder The powder is then cut and put into the compression molding process. The high fluidity during molding transfers the fine irregularities in the mold, leaving ample strength when released from the mold. After the final heat curing, the material has sufficient strength and a smooth surface. fever A hardened metal molding can be obtained.

[0040] The compounding ratio of the thermosetting resin is 20 wt% or less of the metal powder, and the thermosetting resin reacts at the hardening temperature and cools and solidifies. Fever The hardened metal compact has high strength and a smooth surface.

[0041] The pressure required for compression molding of thermosetting resin composited with metal powder in the plasticized temperature range is 2 to 3 tons / cm. 2 It is possible to mold at low pressure. gold In manufacturing, a large amount of lubricant is added, 5 to 7 tons / cm 2 However, there are limitations to applying even greater pressure due to the strength of the mold and the equipment involved, and there are also limitations to the smoothness.

[0042] In this embodiment, the heating temperature during compression molding is set to a value equal to the thermosetting temperature. resin The temperature can be set in accordance with the plasticization temperature of the powder, and can be in the range of 60 to 130°C, and the final hardening temperature after molding and cooling is 160 to 220°C. Furthermore, the final hardening step can be performed by leaving the mixture to stand for about 10 to 30 minutes, and in this embodiment, small-scale equipment such as a regular dryer can be used, which makes it possible to significantly reduce energy costs compared to powder metallurgy processes that require large-scale sintering furnaces. Furthermore, the shrinkage rate is smaller than that of powder metallurgy, and dimensional accuracy can be improved.

[0043] (Other forms) The method for manufacturing a resin molding die of this embodiment described above is one example of a preferred form of the present invention, but it is not limited to this and various modifications are possible within the scope that does not change the gist of the present invention.

[0044] The metal powder is not limited to iron powder. It may be a metal powder such as aluminum, tungsten, stainless steel, titanium, zinc, tin, copper, lead, magnesium, chromium, cobalt, nickel, zirconium, molybdenum, silver, neodymium, platinum, or gold. Alternatively, it may be an alloy containing one or more metals or ceramics selected from the group consisting of iron, aluminum, tungsten, stainless steel, titanium, zinc, tin, copper, lead, magnesium, chromium, cobalt, nickel, zirconium, molybdenum, silver, neodymium, platinum, and gold. For example, iron-based alloys include alloy steel, tool steel, stainless steel, nickel steel, nickel-chromium steel, chromium steel, and maraging steel. Copper alloys, aluminum alloys, titanium alloys, and cemented carbide alloys may also be used.

[0045] heat curing metal Titanate, silane, and graphene oxide surface treatments are used on metal powder to improve bonding strength with thermosetting resins used to form molded bodies. Agent It is possible to use it.

[0046] The thermosetting resin having a B stage to be added to the metal powder preferably has a plasticizing temperature of about 90°C and a hardening temperature of about 200°C.

[0047] In this embodiment, the metal powder and the thermosetting resin are mixed in the heat distortion temperature range. training After dry compounding, or wet compounding using a solvent to form a slurry, the metal-resin composite powder is crushed and classified, and then placed in a mold and compressed at a pressure of 2 to 3 tons / cm. 2 However, depending on the combination of metal powder and added thermosetting particles, the compression pressure may be as low as 2 tons / cm. 2 It may be less than 3 tonnes / cm 2 It may exceed this limit.

[0048] In this embodiment, the plasticization temperature is around 90° C., and the curing temperature is sintering at around 200° C. However, depending on the combination of metal powder and added thermosetting resin, the temperature during compression molding in the B stage is preferably 10° C. or higher than the heat distortion temperature if possible, but 30° C. lower than the curing temperature, and the curing time during which the material is left to stand in a thermostatic chamber set at the curing temperature is 10 to 30 minutes. [Example]

[0049] The metal powder used was a general iron-based metal powder manufactured by the atomization method (Höganäs Somaloy:ASC100.29) , as shown in Table 1 It consists of particle size distribution.

[0050] [Table 1]

[0051] The surface treatment of metal powder to improve bonding with thermosetting resin is performed on a surface of 90 μm or more. powder The cut iron powder is placed in a stirring mixer, and while mixed, a coupling agent diluted with alcohol is added dropwise. The alcohol is evaporated by the shear heat generated during mixing, resulting in surface treatment. The coupling treatment was carried out by placing 6500 g of iron powder in a Henschel mixer and adding dropwise at low speed a treatment solution prepared by dissolving 12.5 g of Ajinomoto Co.'s Plenact 46B, a titanate-based compound, in 62.5 g of ethanol. To evaporate the alcohol with the help of shear heat and heating from the mixing equipment, the mixture was mixed by rotation at 130°C for 45 minutes, then cooled to 40°C using the equipment's cooling device and discharged and collected.

[0052] Thermosetting resins are Toagosei Using E-150BK14S, an epoxy-based and amine-based hardener from the company, a hot plate was heated above its softening point to form a paste, and the titanate-surface-treated iron powder was added in appropriate amounts until the specified ratio was reached, and mixed. training Then cool. The kneading temperature was 130°C, 40°C higher than the softening point of the thermosetting resin E-150BK14S, which is 90°C, and the ratio of thermosetting resin added was 4, 6, and 8 parts by weight per 100 parts of iron powder.

[0053] Iron powder and thermosetting resin are mixed in a paste state. training After cooling, the mixture was crushed at room temperature using a crusher and sieved through a 90 μm sieve. powder The particle size of the resulting ball-shaped coarse iron powder is the same as that of the original iron powder. powder Repeat crushing again. return A 90 μm sieve was used to collect as much as possible.

[0054] A ring-shaped product (outer diameter 19 mm, inner diameter 10 mm, thickness 5.5 mm) was molded at a mold temperature of 140°C and a pressure of 2 ton / cm. 2 The uncured molded product was cooled and released from the mold, and then left to stand in a thermostatic chamber at 200°C for 15 minutes to complete the curing. thermoset metal The crushing strength and surface roughness (Ra, Rz) of the compact were also measured, and the results were Table 2 Shown below.

[0055] [Table 2] [Example]

[0056] Using the same process, a ring-shaped molded product (outer diameter 19 mm, inner diameter 10 mm, thickness 5.5 mm) was molded at a mold temperature of 140°C and a pressure of 3 ton / cm. 2 The uncured molded body was cooled and released from the mold, and then placed in a constant temperature bath at 200°C for 15 minutes to complete the curing. thermoset metal The crushing strength and surface roughness (Ra, Rz) of the compact were also measured, and the results were Table 3 Shown below.

[0057] [Table 3] [Example]

[0058] The uncured molded bodies obtained by molding in the steps of Example 1 and Example 2 were measured for radial crushing strength, and the results are shown below. Table 4 Shown below.

[0059] [Table 4]

[0060] [Comparative Example] As a comparative example, a 90 μm sieve was used to sieve the coarse powder in the same manner as above. powder The iron-based powder was cut and pressed using a conventional powder metallurgy forming process, and similar ring-shaped molded products were created by sintering at 550°C. The crushing strength before and after sintering and the surface roughness after sintering (Ra, Rz) were measured. The results obtained In Table 5 show.

[0061] [Table 5]

[0062] In comparison between the examples and the comparative examples, Radial crushing strength There is a difference of nearly 10 times 、 There is also a big difference in surface roughness 、These differences are considered to be a major advantage of the present invention in terms of the reproducibility of the fine uneven shape in the molding process.

Claims

1. A method for producing a metal-resin composite powder used to produce a thermosetting metal molded product, comprising: a surface treatment step in which the surface of the metal powder having a predetermined particle size is coated with a coupling agent; a compounding step of mixing a plasticized thermosetting resin with the metal powder that has been surface-treated in the surface treatment step to obtain a solidified compound; a crushing step of crushing the solidified composite to obtain a powder; a classification step of removing coarse powder having a particle size equal to or larger than a predetermined particle size from the powder to obtain a powder for compression molding; A method for producing a metal-resin composite powder, comprising:

2. The method for producing a metal-resin composite powder according to claim 1 , wherein the coupling agent is a silane coupling agent, a titanate coupling agent, or graphene oxide.

3. 2. The method for producing a metal-resin composite powder according to claim 1, wherein the compounding step involves bringing the thermosetting resin into a B-stage plastic state at a temperature lower than the curing temperature of the thermosetting resin, kneading the thermosetting resin and the surface-treated metal powder so as to uniformly disperse the thermosetting resin, and then cooling and solidifying the mixture.

4. 2. The method for producing a metal-resin composite powder according to claim 1, wherein the compounding process comprises dissolving the thermosetting resin in a solvent to liquefy it, compounding the surface-treated metal powder in a slurry state so as to uniformly disperse the resin, and then removing the solvent by evaporation to solidify the mixture.

5. A method for producing a metal resin composite powder as described in claim 1, wherein in the compounding process, the thermosetting resin is mixed with the metal powder at 20 wt% or less to obtain the composite, this composite is crushed in the crushing process to obtain the powder, and in the classification process, the powder is classified to have a particle size of 100 μm or less.

6. A method for manufacturing a thermosetting metal molded body, comprising: pouring the metal-resin composite powder described in claim 1 into a mold; heating the powder to a B-stage temperature at which the thermosetting resin becomes plastic using the mold; compressing and molding the powder; cooling and solidifying the powder within the mold; and releasing the powder from the mold and hardening it in an atmosphere at the hardening temperature of the thermosetting resin to obtain a molded body.

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