Forming agent, preparation method of forming agent, hard alloy and preparation method of hard alloy

Abstract

The invention relates to the technical field of powder metallurgy, and discloses a forming agent and a preparation method thereof, and a hard alloy and a preparation method thereof. The forming agent is prepared from, by mass, 45%-55% of paraffin, 25%-35% of polyethylene glycol, 12%-18% of stearic acid and 5%-8% of the sum of fatty alcohol-polyoxyethylene ether and oleic acid, and the mass ratio of the fatty alcohol-polyoxyethylene ether to the oleic acid is (2-6): 1. The forming agent improves the forming process and improves the quality of the prepared hard alloy.

Description

Technical Field

[0001] This application relates to the field of powder metallurgy technology, specifically to forming agents and their preparation methods, and cemented carbides and their preparation methods. Background Technology

[0002] Powder metallurgy is a crucial process for preparing cemented carbide products with high aspect ratios, such as micro drills, end mills, and bars. The role of forming agents in powder metallurgy affects multiple forming processes, including the rheological behavior of the feedstock, the dispersion state of the powder, and the mechanical properties of the green body. Adding forming agents acts as a temporary carrier in powder metallurgy, improving the formability and plasticity of the powder. Therefore, efficient and easily removable forming agents are essential for powder metallurgy technology.

[0003] It should be noted that the above statements are only used to provide background information related to this application and do not necessarily constitute prior art. Summary of the Invention

[0004] In a first aspect of this application, a molding agent is provided, comprising, by mass percentage: 45%~55% paraffin wax, 25%~35% polyethylene glycol, 12%~18% stearic acid, and 5%~8% fatty alcohol polyoxyethylene ether and oleic acid; wherein the mass ratio of the fatty alcohol polyoxyethylene ether to the oleic acid is (2~6):1.

[0005] In some embodiments, the fatty alcohol polyoxyethylene ether is 4% to 6% by weight, and the oleic acid is 1% to 2%.

[0006] In some embodiments, at least one of the following conditions is met: the average molecular weight of the polyethylene glycol is 2000-3000; the fatty alcohol polyoxyethylene ether includes at least one of AEO-5, AEO-7, and AEO-3.

[0007] In a second aspect of this application, a method for preparing the molding agent of this application is provided, comprising: performing a first mixing treatment on paraffin and polyethylene glycol to obtain a first matrix; performing a second mixing treatment on the first matrix and stearic acid to obtain a second matrix; and adding a mixture of fatty alcohol polyoxyethylene ether and oleic acid dropwise to the second matrix for a third mixing treatment to obtain the molding agent.

[0008] In some embodiments, the stirring speed of the first mixing process is 90 rpm to 120 rpm; the temperature of the first mixing process is 65°C to 75°C.

[0009] In some embodiments, the stirring speed of the second mixing process is 60 rpm to 80 rpm; the temperature of the second mixing process is 70°C to 80°C.

[0010] In some embodiments, the stirring speed of the third mixing process is 40 rpm to 60 rpm; the time of the third mixing process is 90 min to 150 min.

[0011] In a third aspect, this application provides a method for preparing cemented carbide, comprising: using the forming agent of this application and / or the forming agent prepared by the method of this application; and subjecting cemented carbide powder and the forming agent to a mixing process, an extrusion molding process, a degreasing process, and a sintering process to obtain cemented carbide.

[0012] In some embodiments, the molding agent accounts for 5% to 8% by mass of the material obtained after the mixing treatment.

[0013] In some embodiments, at least one of the following conditions is met: the viscosity of the material obtained after the mixing treatment is ≤800 Pa·s at 75°C~85°C; the flexural strength of the green body obtained after the extrusion molding treatment is ≥6 MPa and the surface roughness Ra is ≤1.6 μm; the heating rate is controlled at 3°C / min~5°C / min during the degreasing treatment; and the density of the sintered body obtained after the sintering treatment is ≥99.5%.

[0014] In a fourth aspect, this application proposes a cemented carbide using the forming agent proposed in this application.

[0015] In some embodiments, the cemented carbide includes at least one of WC-Co based cemented carbide, WC-TiC-Co based cemented carbide, WC-TaC-Co based cemented carbide, and WC-NbC-Co based cemented carbide.

[0016] The beneficial effects of the technical solution proposed in this application include at least the following: The forming agent of this application greatly reduces the internal friction between powders and between powders and mold walls during the preparation of cemented carbide through combination and compounding, and effectively prevents powder agglomeration. As an organic continuous phase in powder metallurgy feedstock, the forming agent improves the flowability and uniformity of the powder-forming agent system, affects the rheological behavior of the powder system, and thus improves the mechanical properties of the prepared cemented carbide. Detailed Implementation

[0017] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit this application; unless otherwise stated, the values ​​of the parameters mentioned in this application can be measured using various measurement methods commonly used in the art (e.g., they can be tested according to the methods given in the embodiments of this application).

[0018] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are open-ended expressions, meaning they include what is specified in this application but do not exclude other aspects.

[0019] In the description of this application, all figures disclosed herein, whether or not the words "approximately" or "about" are used, are approximate values. Each figure may vary by less than 10% or by a difference that is considered reasonable by one of the art, such as 1%, 2%, 3%, 4%, or 5%.

[0020] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for a specific parameter, it is also expected that ranges of 60~110 and 80~120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this application, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0021] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0022] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0023] Forming agents are crucial additives in the preparation of cemented carbide. The functions of each component in the forming agent and their effects on the formability of alloy powder and the defect rate of the prepared cemented carbide are important factors.

[0024] In related technologies, the forming agent used for cemented carbide has poor lubrication effect, which leads to the need to apply greater pressure when the alloy powder is extruded in the mold or extruded and demolded. This results in low forming efficiency of cemented carbide and is prone to defects such as green blank breakage, degreasing cracking, and sintering deformation.

[0025] The molding agent proposed in this application is designed through the interaction of related components at the molecular level to construct a multi-component molding agent with synergistic effects, thereby simultaneously improving the flowability, dispersibility, and degreasing safety of the molding machine and improving the mechanical properties of the prepared cemented carbide.

[0026] In a first aspect of this application, a molding agent is provided, comprising, by mass percentage: 45%~55% paraffin wax, 25%~35% polyethylene glycol, 12%~18% stearic acid, and 5%~8% fatty alcohol polyoxyethylene ether and oleic acid; wherein the mass ratio of the fatty alcohol polyoxyethylene ether to the oleic acid is (2~6):1.

[0027] The molding agent of this application is a combination of the aforementioned components within the above-mentioned range, exhibiting good flowability and powder dispersibility. Paraffin wax, as a low-melting-point component, provides the basic flowability of the molding agent. Polyethylene glycol and paraffin wax work together to improve the plastic deformation capacity of the feedstock at extrusion temperatures. Furthermore, the aforementioned mixed system containing hydrophilic components facilitates green degreasing during processing, reducing the use of toxic organic solvents. Stearic acid, fatty alcohol polyoxyethylene ether, and oleic acid constitute a highly efficient lubricating-dispersing system, which is mixed in the molding agent at the aforementioned addition amounts. Through combined compounding and synergistic effects, it greatly reduces the internal friction between cemented carbide powders and between cemented carbide powders and the die wall during cemented carbide preparation, and effectively prevents cemented carbide powder agglomeration. The molding agent, as an organic continuous phase in powder metallurgy feedstock, improves the flowability and uniformity of the cemented carbide powder-molding agent system, affects the rheological behavior of the cemented carbide powder system, and thus improves the mechanical properties of the prepared cemented carbide. Therefore, it achieves both improvement in the molding process and enhancement of the quality of the prepared cemented carbide.

[0028] As an example, the paraffin content is 45%, 48%, 50%, 52%, or 55%.

[0029] As an example, the percentage of polyethylene glycol is 25%, 28%, 30%, 32%, or 35%.

[0030] As an example, the stearic acid content is 12%, 13%, 14%, 15%, 16%, 17%, or 18%.

[0031] As an example, the sum of fatty alcohol polyoxyethylene ether and oleic acid is 5%, 5.5%, 6%, 6.5%, 7%, 7.5% or 8%.

[0032] As an example, the mass ratio of fatty alcohol polyoxyethylene ether to oleic acid is 2:1, 3:1, 4:1, 5:1, or 6:1.

[0033] In some embodiments, the fatty alcohol polyoxyethylene ether (AEO) comprises 4% to 6% by weight, and the oleic acid comprises 1% to 2%. Within the aforementioned range, the fatty alcohol polyoxyethylene ether (AEO) can improve the compatibility between the components of the molding agent and the interfacial wettability between the cemented carbide powder and the binder, thereby enhancing the uniformity of the feed. Combined with the effect of oleic acid, it achieves efficient dispersion and lubrication by forming an adsorption layer on the surface of the cemented carbide powder. This reduces the internal friction of the cemented carbide powder particles and the external friction between the feed and the mold wall, synergistically optimizing the feed rheological behavior and improving molding stability and green quality.

[0034] As an example, the proportion of fatty alcohol polyoxyethylene ether is 4%, 4.5%, 5%, 5.5%, or 6%. In some embodiments, at least one of the following conditions is met: the average molecular weight of the polyethylene glycol is 2000-3000; the fatty alcohol polyoxyethylene ether includes at least one of AEO-5, AEO-7, and AEO-3. Within the aforementioned range, the molecular weight of the polyethylene glycol or the chain length of the AEO can be optimally adapted to cemented carbide powders of different particle sizes and specific surface areas, enabling the molding agent to achieve good lubricity. This is beneficial for improving the smoothness of the green surface and enhancing the dimensional accuracy of the product.

[0035] In a second aspect of this application, a method for preparing the molding agent of this application is provided, comprising: performing a first mixing treatment on paraffin and polyethylene glycol to obtain a first matrix; performing a second mixing treatment on the first matrix and stearic acid to obtain a second matrix; and adding a mixture of fatty alcohol polyoxyethylene ether and oleic acid dropwise to the second matrix for a third mixing treatment to obtain the molding agent.

[0036] The method described in this application prepares a molding agent by first constructing a homogeneous first matrix of paraffin wax and polyethylene glycol through stepwise mixing, and then gradually compounding various functional components. This effectively improves the mixing uniformity of the system, reduces deficiencies such as polymer agglomeration and local phase enrichment, and allows for precise control of the actual proportions of each component. This enables the synergistic effects of rheological regulation, interfacial lubrication, and crosslinking enhancement, ultimately yielding a molding agent with uniform composition, stable performance, and controllable rheological behavior. This, in turn, improves feed dispersion, flowability, and the quality of the formed preform, thereby enhancing the quality of the prepared cemented carbide.

[0037] In some embodiments, the stirring speed of the first mixing treatment is 90 rpm to 120 rpm; the temperature of the first mixing treatment is 65°C to 75°C. Under the aforementioned conditions, it is beneficial for the water-soluble polyethylene glycol and paraffin to be fully mixed, resulting in the first matrix of the two-phase blended composite wax-based system. This facilitates further thorough mixing of the multiple components in the subsequent process.

[0038] In some embodiments, the stirring speed of the second mixing treatment is 60 rpm to 80 rpm; the temperature of the second mixing treatment is 70°C to 80°C. Performing the second mixing treatment under the aforementioned conditions adjusts the melting state of stearic acid and the first matrix, which is beneficial for their thorough mixing. This reduces the interfacial tension of the second matrix, which in turn improves the wettability and lubricity of the forming agent on the cemented carbide powder.

[0039] In some embodiments, the stirring speed of the third mixing treatment is 40 rpm to 60 rpm; the time of the third mixing treatment is 90 min to 150 min. Thus, a molding agent with uniformly distributed components is prepared through thorough mixing.

[0040] In a third aspect, this application proposes a method for preparing cemented carbide, comprising: using a forming agent of this application and / or a forming agent prepared by the method of this application; and subjecting cemented carbide powder and the forming agent to a mixing process, an extrusion molding process, a degreasing process, and a sintering process to obtain cemented carbide. Thus, the forming agent assists in the molding of cemented carbide powder to prepare high-quality cemented carbide.

[0041] In some embodiments, the molding agent accounts for 5% to 8% by mass of the material obtained after the mixing treatment.

[0042] As an example, the mass percentage of the molding agent in the material obtained after the mixing treatment is 5%, 6%, 7%, or 8%.

[0043] In some embodiments, the material obtained after the mixing process has a viscosity ≤800 Pa·s at 75°C~85°C. This improves the dimensional accuracy of the prepared cemented carbide and reduces surface and internal defects in the material.

[0044] In some embodiments, after the extrusion molding process, the resulting green compact has a bending strength ≥6 MPa and a surface roughness Ra ≤1.6 μm. The green compact's bending strength reaches the aforementioned range, resulting in high structural stability and low defect sensitivity during subsequent processing such as handling, debinding, and sintering. This is beneficial for preparing cemented carbides with high sintering density, stable performance, fewer processing defects, and good product consistency. The low surface roughness and fewer micropores within the green compact, along with the uniform bonding of the cemented carbide powder, allow for the formation of a high-density and uniformly dense cemented carbide after sintering. This is beneficial for preparing cemented carbides with high hardness, high strength, and high wear resistance.

[0045] In some embodiments, during the degreasing process, the heating rate is controlled at 3°C / min to 5°C / min. This facilitates the complete removal of the molding agent.

[0046] In some embodiments, after the sintering treatment, the density of the sintered body is ≥99.5%. This helps to reduce internal defects in the cemented carbide and improve the mechanical properties of the prepared cemented carbide.

[0047] In a fourth aspect, this application discloses a cemented carbide prepared using the forming agent described herein. The cemented carbide prepared using the forming agent exhibits a uniform, dense green blank with few defects. After debinding and sintering, the resulting cemented carbide has a density close to the theoretical density, with no internal microcracks and no axial cracks on the surface. Therefore, the cemented carbide of this application possesses excellent mechanical properties and is suitable for high-performance micro-drills and other machining tools.

[0048] In some embodiments, the cemented carbide includes at least one of WC-Co based cemented carbide, WC-TiC-Co based cemented carbide, WC-TaC-Co based cemented carbide, and WC-NbC-Co based cemented carbide.

[0049] The following specific embodiments illustrate the solution of this application. It should be noted that these embodiments are for illustrative purposes only and should not be considered as limiting the scope of this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0050] Example 1 Molding agent composition: by mass percentage, paraffin (PW) 50%, polyethylene glycol (PEG-2000, molecular weight 2000) 30%, stearic acid (SA) 14%, fatty alcohol polyoxyethylene ether (AEO-5) 4%, oleic acid 2%. Among them, the total content of AEO and oleic acid is 6%, and the mass ratio of fatty alcohol polyoxyethylene ether to oleic acid is 2:1.

[0051] The specific preparation method is as follows: S1: Paraffin wax and polyethylene glycol are added to a reaction vessel, heated to 70°C to melt, and stirred to mix evenly for the first mixing treatment to obtain the first matrix; S2: Stearic acid is added to the first matrix and stirred at 75°C until completely dissolved to perform a second mixing treatment, thereby obtaining the second matrix; S3: Keep the temperature at 75°C, slowly add the pre-mixed fatty alcohol polyoxyethylene ether (AEO-5) and oleic acid mixture to the second matrix dropwise, and continue stirring for 90 minutes to perform the third mixing treatment to obtain the molding agent.

[0052] Preparation of cemented carbide: (1) Mixing treatment: 89.35%WC-10%Co-0.65%Cr3C2 cemented carbide powder and the above-mentioned molding agent are added to the mixing equipment and mixed at 75°C~85°C for 24 hours to obtain uniform extrusion feed. The mass percentage of the molding agent in the material obtained after mixing treatment is 5%.

[0053] (2) Extrusion molding process: The extrusion feed is fed into the extruder and extruded at 85°C to obtain a rod-shaped green billet with a diameter of 2.0 mm.

[0054] (3) Degreasing treatment: The green body is placed in a vacuum drying oven and degreased at 90°C to remove low-temperature volatile components; then it is transferred to a dewaxing oven for hot degreasing, and the heating rate is controlled at 3°C / min to remove the molding agent.

[0055] (4) Sintering treatment: Vacuum sintering is performed on the degreased billet to obtain cemented carbide rod products.

[0056] Example 2 Example 2 is consistent with Example 1, except that the molding agent composition, by mass percentage, is: paraffin 45%, polyethylene glycol (PEG-2500, molecular weight 2500) 35%, stearic acid 13.75%, fatty alcohol polyoxyethylene ether (AEO-7) 5%, and oleic acid 1.25%. The total content of AEO and oleic acid is 6.25%, and the mass ratio of fatty alcohol polyoxyethylene ether to oleic acid is 4:1. During the preparation process, the temperature of the first mixing treatment is 65°C; the temperature of the second mixing treatment is 70°C; and the time of the third mixing treatment is 120 minutes.

[0057] Example 3 Example 3 is consistent with Example 1, except that the molding agent composition, by mass percentage, is: paraffin 55%, polyethylene glycol (PEG-3000, molecular weight 3000) 25%, stearic acid 13%, fatty alcohol polyoxyethylene ether (AEO-5) 6%, and oleic acid 1%. The total content of AEO and oleic acid is 7%, with a mass ratio of 6:1. During the preparation process, the temperature of the first mixing treatment is 75°C; the temperature of the second mixing treatment is 80°C; and the time of the third mixing treatment is 150 minutes.

[0058] Example 4 Example 4 is consistent with Example 1, except that the molding agent composition, by mass percentage, is: paraffin 53%, polyethylene glycol (PEG-2500, molecular weight 2500) 28%, stearic acid 14%, fatty alcohol polyoxyethylene ether (AEO-5) 4%, and oleic acid 1%. The total content of AEO and oleic acid is 5%, with a mass ratio of 4:1. During the preparation process, the temperature of the first mixing treatment is 75°C; the temperature of the second mixing treatment is 80°C; and the time of the third mixing treatment is 120 minutes.

[0059] Example 5 Example 5 is consistent with Example 1, except that the molding agent composition, by mass percentage, is: paraffin 45%, polyethylene glycol (PEG-3000, molecular weight 3000) 31%, stearic acid 16%, fatty alcohol polyoxyethylene ether (AEO-5) 6%, and oleic acid 2%. The total content of AEO and oleic acid is 8%, with a mass ratio of 4:1. During the preparation process, the temperature of the first mixing treatment is 65°C; the temperature of the second mixing treatment is 70°C; and the time of the third mixing treatment is 135 minutes.

[0060] Comparative Example 1 Comparative Example 1 is consistent with Example 1, except that the total content of AEO-5 and oleic acid is 6%, and the mass ratio is 1:1 (i.e., AEO-5 is 3% and oleic acid is 3%). The remaining components are: paraffin 50%, PEG-2000 30%, and stearic acid 14%.

[0061] Comparative Example 2 Comparative Example 2 is the same as Example 1, except that all components (paraffin, PEG, stearic acid, AEO-5, oleic acid) were added to the reaction vessel at 75°C at one time, and stirring was started at the same time and continued for 90 minutes to obtain the molding agent.

[0062] Comparative Example 3 Comparative Example 3 is consistent with Example 1, except that the total content of AEO-5 and oleic acid is 4%, and the mass ratio is 3:1 (i.e., AEO-5 is 3% and oleic acid is 1%). The remaining components are: paraffin 50%, PEG-2000 30%, and stearic acid 16%.

[0063] Comparative Example 4 Comparative Example 4 is the same as Example 1, except that the mass percentage of the molding agent in the material obtained after the mixing process is 3%.

[0064] The differences between the other embodiments and comparative examples, as well as the test results, are shown in Table 1.

[0065] Table 1

[0066] Test method: 1. Feed viscosity test After mixing the cemented carbide powder and the aforementioned composite molding agent in a mixing apparatus according to the specified mass ratio, a uniform extrusion feed is obtained. The viscosity of the extrusion feed is then tested using a capillary rheometer at 85°C.

[0067] 2. Green body performance testing (green body strength and surface roughness) The extrusion feedstock was fed into an extruder and extruded at 85°C to obtain a rod-shaped green compact with a diameter of 2.0 mm. After standing at room temperature for 30 min, the strength of the green compact was tested using the three-point bending method. The surface morphology and roughness of the sample were obtained by non-contact scanning using a white light interferometer.

[0068] 3. Testing of cemented carbide rod products The degreased billet was vacuum sintered at a temperature of 1380℃~1480℃ and a vacuum degree of 0.1Pa~10Pa to obtain cemented carbide rod products. The sintered density of the products was tested using Archimedes' displacement method.

[0069] The appearance test includes: randomly selecting 5 samples to be inspected under a 100x optical microscope and checking them one by one. If there are no macroscopic cracks on the surface, the sample is considered qualified.

[0070] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. "First feature" and "second feature" may include one or more of the indicated feature.

[0071] In the description of this application, "multiple" means two or more.

[0072] In the description of this application, "A and / or B" can include any of the cases of A alone, B alone, or A and B, where A and B are merely examples and can be any technical feature connected by "and / or" in this application.

[0073] In this application, the order in which the steps are written does not imply a strict execution order and does not limit the implementation process in any way. The specific execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps in this application can be performed sequentially or randomly, preferably sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0074] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A molding agent, characterized in that, By weight percentage, including: Paraffin wax 45%~55%, polyethylene glycol 25%~35%, stearic acid 12%~18%, fatty alcohol polyoxyethylene ether and oleic acid 5%~8%; the mass ratio of the fatty alcohol polyoxyethylene ether to the oleic acid is (2~6):

1.

2. The molding agent according to claim 1, characterized in that, The fatty alcohol polyoxyethylene ether is 4% to 6% by mass percentage, and the oleic acid is 1% to 2%.

3. The molding agent according to claim 1 or 2, characterized in that, At least one of the following conditions must be met: The average molecular weight of the polyethylene glycol is 2000-3000; The fatty alcohol polyoxyethylene ether includes at least one of AEO-5, AEO-7, and AEO-3.

4. A method for preparing the molding agent according to any one of claims 1 to 3, characterized in that, include: Paraffin wax and polyethylene glycol are subjected to a first mixing treatment to obtain a first matrix; The first matrix is ​​mixed with stearic acid to obtain a second matrix; A mixture of fatty alcohol polyoxyethylene ether and oleic acid is added dropwise to the second matrix for a third mixing treatment to obtain the molding agent.

5. The method according to claim 4, characterized in that, Meet at least one of the following: The stirring speed for the first mixing process is 90 rpm to 120 rpm; The temperature of the first mixing process is 65℃~75℃; The stirring speed for the second mixing process is 60 rpm to 80 rpm; The temperature for the second mixing treatment is 70℃~80℃; The stirring speed for the third mixing process is 40 rpm to 60 rpm; The third mixing process takes 90 to 150 minutes.

6. A method for preparing cemented carbide, characterized in that, include: A molding agent prepared using the molding agent according to any one of claims 1 to 3 and / or the method according to any one of claims 4 to 5; The cemented carbide powder is mixed with the forming agent, extruded, degreased, and sintered to obtain cemented carbide.

7. The method according to claim 6, characterized in that, The molding agent accounts for 5% to 8% of the mass of the material obtained after the mixing process.

8. The method according to claim 6 or 7, characterized in that, Meet at least one of the following: The material obtained after the mixing process has a viscosity of ≤800 Pa·s at 75℃~85°C. After the extrusion molding process, the resulting green body has a bending strength ≥ 6 MPa and a surface roughness Ra ≤ 1.6 μm; During the degreasing process, the heating rate is controlled at 3℃ / min~5℃ / min; After the sintering treatment, the density of the sintered body is ≥99.5%.

9. A cemented carbide, characterized in that, Prepared using the molding agent described in any one of claims 1 to 3.

10. The cemented carbide according to claim 9, characterized in that, The cemented carbide includes at least one of WC-Co based cemented carbide, WC-TiC-Co based cemented carbide, WC-TaC-Co based cemented carbide, and WC-NbC-Co based cemented carbide.

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