Ball milling process for ultra-coarse hard alloy

Abstract

The invention belongs to the technical field of hard alloy, and particularly relates to a ball milling process of ultra-coarse hard alloy, which comprises the following steps: S1, weighing ultra-coarse tungsten carbide powder, a binder and an additive as raw materials according to the composition of the hard alloy, proportioning, and taking a forming agent for later use; s2, a binder, an additive and a forming agent are added into a ball mill, oleic acid and absolute ethyl alcohol are added for primary ball milling, and slurry is taken out for standby application after ball milling is completed; s3, absolute ethyl alcohol, the slurry obtained in the step S2 and ultra-coarse tungsten carbide powder are taken and added into an ultrasonic mixer to be subjected to ultrasonic mixing, and mixed slurry is obtained after mixing is completed; and S4, adding the mixed slurry into the ball mill for secondary ball milling, and obtaining a final slurry product after ball milling is finished. According to the preparation method disclosed by the invention, ultrasonic mixing and ball milling processes are combined, crushing of ultra-coarse particle tungsten carbide is effectively reduced through extremely short ball milling time, and meanwhile, all the components can be fully and uniformly mixed.

Description

Technical Field

[0001] The present invention belongs to the technical field of cemented carbides, and particularly relates to a ball milling process for ultra-coarse cemented carbides. Background Art

[0002] Cemented carbide is a composite material composed of refractory metal compounds (such as WC, TaC, NbC, TiC, etc.) and binder metals (such as Co, Ni, Fe, etc.), and is made through powder metallurgy process, with a combination of hardness, strength and toughness. Cemented carbide is widely used as a tool material, such as turning tools, milling cutters, planing cutters, etc. Cemented carbide has a series of good properties such as high hardness, wear resistance, good strength and toughness, heat resistance, corrosion resistance, etc.

[0003] With the rapid development of the national industry, the demand for ultra-fine and ultra-coarse grain tungsten carbide cemented carbide materials is gradually increasing. The demand for ultra-coarse grain cemented carbide in the application of high-impact load working conditions in mining is large. Since ultra-coarse grain tungsten carbide is broken by the impact of grinding balls in the ball mill during the ball milling process, when preparing ultra-coarse grain cemented carbide, while ensuring that the raw materials require a certain Fsss particle size, a reasonable ball milling process is also needed to reduce the breakage of tungsten carbide during the ball milling process.

[0004] At present, the ultra-coarse grain ball milling process uses methods such as reducing the ball-to-material ratio and reducing the ball milling time to reduce the ball milling efficiency to achieve the purpose of reducing the breakage of ultra-coarse grain tungsten carbide particles. However, reducing the ball milling time is likely to cause problems such as uneven dispersion of components, and metallographic defects such as coarse grain aggregation, additive segregation, and cobalt aggregation. Summary of the Invention

[0005] To solve the problems existing in the prior art, the main object of the present invention is to propose a ball milling process for ultra-coarse cemented carbides.

[0006] To solve the above technical problems, according to one aspect of the present invention, the following technical solutions are provided: A ball milling process for ultra-coarse cemented carbides, the process comprising the following steps: S1. Batching: According to the composition of the cemented carbide, weigh ultra-coarse tungsten carbide powder, binder, and additive as raw materials for batching, and reserve a molding agent; S2. Primary ball milling: Add the binder, additive, and molding agent into a ball mill, and then add oleic acid and absolute ethanol for primary ball milling. After the ball milling is completed, the slurry is taken out and reserved; S3. Ultrasonic mixing: Take absolute ethanol, the slurry obtained in step S2, and ultra-coarse tungsten carbide powder and add them into an ultrasonic mixer for ultrasonic mixing. After the mixing is completed, a mixed slurry is obtained; S4. Secondary ball milling: Add the mixed slurry into a ball mill for secondary ball milling. After the ball milling is completed, a final slurry product is obtained.

[0007] As a preferred embodiment of the ball milling process for ultra - coarse cemented carbide according to the present invention, in step S1, by weight percentage, the raw materials are: 93.5 - 94 wt% of ultra - coarse tungsten carbide powder, 5.5 - 6.5 wt% of binder, and 0 - 0.5 wt% of additive; the forming agent is added separately at 2 wt% of the total weight of the raw materials.

[0008] As a preferred embodiment of the ball milling process for ultra - coarse cemented carbide according to the present invention, in step S1, the average Fsss particle size of the ultra - coarse tungsten carbide powder is 17 - 23 μm, the average Fsss particle size of the binder is 80 - 120 nm, and the average Fsss particle size of the additive is 0.8 - 1.2 μm.

[0009] As a preferred embodiment of the ball milling process for ultra - coarse cemented carbide according to the present invention, in step S1, the additive is other metal carbides except tungsten, including at least one of chromium carbide, tantalum carbide, titanium carbide, and niobium carbide; the binder is cobalt powder; and the forming agent is paraffin.

[0010] As a preferred embodiment of the ball milling process for ultra - coarse cemented carbide according to the present invention, in step S2, during the first ball milling process, oleic acid is added at a liquid - to - solid ratio of 1.4 - 1.6 mL / kg, absolute ethanol is added at a liquid - to - solid ratio of 0.26 - 0.28 L / kg, the ball - to - material ratio is (1.5 - 3):1, the ball milling time is 5 - 6 h, and the rotational speed of the ball mill is 36 - 38 r / min.

[0011] As a preferred embodiment of the ball milling process for ultra - coarse cemented carbide according to the present invention, in step S3, absolute ethanol is added at a liquid - to - solid ratio of 0.6 - 0.8 L / kg, and the ultrasonic power is 3.0 - 5.0 kW.

[0012] As a preferred embodiment of the ball milling process for ultra - coarse cemented carbide according to the present invention, in step S3, the ultra - coarse tungsten carbide powder and the slurry obtained in step S2 are simultaneously added to the ultrasonic mixer. Among them, the feeding speed of the ultra - coarse tungsten carbide powder is 1.8 - 2.2 kg / min, and the feeding speed of the slurry is 0.18 - 0.22 kg / min.

[0013] As a preferred embodiment of the ball milling process for ultra - coarse cemented carbide according to the present invention, in step S4, during the second ball milling process, the liquid - to - solid ratio is 0.25 - 0.30 L / kg, the ball - to - material ratio is (1.0 - 2.0):1, the ball milling time is 2 - 6 h, and the rotational speed of the ball mill is 36 - 38 r / min.

[0014] The beneficial effects of the present invention are as follows: 1. The present invention utilizes the ultrasonic cavitation effect to fully disperse and uniformly mix ultra-coarse tungsten carbide powder with a forming agent, a binder, an additive, etc.; meanwhile, by the driving of ultrasonic waves, the collision between tungsten carbide particles is increased, the tungsten carbide particles are activated, and nano-scale cobalt powder is selected, which is more easily dispersed under the action of ultrasonic waves and has a strong wrapping effect on ultra-coarse tungsten carbide.

[0015] 2. The process method of ball milling twice in the present invention has a shorter grinding time compared with the traditional ball milling process, which not only ensures the uniform dispersion of the materials but also effectively reduces the breakage of ultra-coarse tungsten carbide. Brief Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0017] Figure 1 It is the metallographic photograph of the cemented carbide prepared in Example 1 of the present invention.

[0018] Figure 2 It is the metallographic photograph of the cemented carbide prepared in Example 2 of the present invention.

[0019] Figure 3 It is the metallographic photograph of the cemented carbide prepared in Example 3 of the present invention.

[0020] Figure 4 It is the metallographic photograph of the cemented carbide prepared in Comparative Example 1 of the present invention.

[0021] Figure 5 It is the metallographic photograph of the cemented carbide prepared in Comparative Example 2 of the present invention.

[0022] Figure 6 It is the metallographic photograph of the cemented carbide prepared in Comparative Example 3 of the present invention.

[0023] Figure 7 It is the metallographic photograph of the cemented carbide prepared in Comparative Example 4 of the present invention.

[0024] Figure 8 It is the metallographic photograph of the cemented carbide prepared in Comparative Example 5 of the present invention.

[0025] Figure 9 It is the metallographic photograph of the cemented carbide prepared in Comparative Example 6 of the present invention.

[0026] The realization of the object, functional features, and advantages of the present invention will be further described with reference to the embodiments and the drawings. Detailed Embodiments

[0027] The technical solutions in the embodiments will be clearly and completely described below. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] According to one aspect of the present invention, the present invention provides the following technical solutions: A ball milling process for ultra-coarse cemented carbide, the process comprising the following steps: S1. Batching: According to the composition of the cemented carbide, weigh ultra-coarse tungsten carbide powder, binder, and additive as raw materials for batching, and reserve the molding agent; S2. Primary ball milling: Add the binder, additive, and molding agent into a ball mill, and then add oleic acid and absolute ethanol for primary ball milling. After the ball milling is completed, the slurry is taken out and reserved; S3. Ultrasonic mixing: Add absolute ethanol, the slurry obtained in step S2, and ultra-coarse tungsten carbide powder into an ultrasonic mixer for ultrasonic mixing. After the mixing is completed, a mixed slurry is obtained; S4. Secondary ball milling: Add the mixed slurry into a ball mill for secondary ball milling. After the ball milling is completed, a final slurry product is obtained.

[0029] The final slurry product obtained by the ball milling process of the present invention can be used for pressing after spray drying. The present invention combines ultrasonic mixing with the traditional ball milling process. Through an extremely short ball milling time, the crushing of ultra-coarse tungsten carbide particles is effectively reduced, and at the same time, each component can ensure sufficient and uniform mixing.

[0030] Specifically, the present invention utilizes the ultrasonic cavitation effect to fully disperse and uniformly mix the ultra-coarse tungsten carbide powder, molding agent, binder, additive, etc. At the same time, driven by ultrasonic waves, the collision between tungsten carbide particles is increased, the tungsten carbide particles are activated, and nano-level binders are selected. Under the action of ultrasonic waves, they are more easily dispersed and have a strong wrapping effect on ultra-coarse tungsten carbide. The process method of two-stage ball milling in the present invention has a shorter grinding time than the traditional ball milling process, which not only ensures the uniform dispersion of the materials but also effectively reduces the crushing of ultra-coarse tungsten carbide.

[0031] Preferably, in the step S1, by weight percentage, the raw materials are: 93.5 - 94 wt% of ultra-coarse tungsten carbide powder, 5.5 - 6.5 wt% of binder, 0 - 0.5 wt% of additive; the molding agent is added separately at 2 wt% of the total weight of the raw materials.

[0032] Preferably, in the step S1, the average Fsss particle size of the ultra-coarse tungsten carbide powder is 17 - 23 μm, the average Fsss particle size of the binder is 80 - 120 nm, and the average Fsss particle size of the additive is 0.8 - 1.2 μm.

[0033] Preferably, in the step S1, the additive is a metal carbide other than tungsten, including at least one of chromium carbide, tantalum carbide, titanium carbide, and niobium carbide, the binder is cobalt powder, and the shaping agent is paraffin.

[0034] Preferably, in the step S2, during the primary ball milling process, oleic acid is used to promote the dispersion of paraffin. Oleic acid is added at a liquid-solid ratio of 1.4 - 1.6 mL / kg, and absolute ethanol is used as the ball milling medium and added at a liquid-solid ratio of 0.26 - 0.28 L / kg. The ball-to-material ratio is (1.5 - 3):1, the ball milling time is 5 - 6 h, and the rotation speed of the ball mill is 36 - 38 r / min.

[0035] Preferably, in the step S3, absolute ethanol is added at a liquid-solid ratio of 0.6 - 0.8 L / kg, and the ultrasonic power is 3.0 - 5.0 kW.

[0036] Preferably, in the step S3, the ultra-coarse tungsten carbide powder and the slurry obtained in the step S2 are simultaneously added to the ultrasonic mixer. Among them, the feeding speed of the ultra-coarse tungsten carbide powder is 1.8 - 2.2 kg / min, and the feeding speed of the slurry is 0.18 - 0.22 kg / min. After the feeding is completed, the mixture is continued for 1 - 1.5 h.

[0037] Preferably, in the step S4, during the secondary ball milling process, the liquid-solid ratio is adjusted (for example, by extracting the excess absolute ethanol to adjust the liquid-solid ratio) to 0.25 - 0.30 L / kg, the ball-to-material ratio is (1.0 - 2.0):1, the ball milling time is 2 - 6 h, and the rotation speed of the ball mill is 36 - 38 r / min.

[0038] The technical solution of the present invention will be further described below in conjunction with specific embodiments.

[0039] Example 1 A ball milling process for ultra-coarse cemented carbide includes the following steps: S1. Batching: According to the composition of cemented carbide, weigh extra-coarse tungsten carbide powder, binder, and additive as raw materials for batching, and reserve the molding agent; by weight percentage, the raw materials are: 93.7 wt% of extra-coarse tungsten carbide powder, 6.0 wt% of binder, and 0.3 wt% of additive; the molding agent is added separately at 2 wt% of the total weight of the raw materials. The average Fsss particle size of the extra-coarse tungsten carbide powder is 20 μm, the average Fsss particle size of the binder is 100 nm, and the average Fsss particle size of the additive is 1.0 μm. The additive is tantalum carbide, the binder is cobalt powder, and the molding agent is paraffin; S2. Primary ball milling: Add the binder, additive, and molding agent into a ball mill, then add oleic acid and absolute ethanol for primary ball milling. After the ball milling is completed, take out the slurry for standby; add oleic acid at a liquid-solid ratio of 1.5 mL / kg, add absolute ethanol at a liquid-solid ratio of 0.26 L / kg, the ball-to-material ratio is 2:1, the ball milling time is 5 h, and the rotation speed of the ball mill is 38 r / min; S3. Ultrasonic mixing: Add absolute ethanol, the slurry obtained in step S2, and extra-coarse tungsten carbide powder into an ultrasonic mixer for ultrasonic mixing. After the mixing is completed, obtain a mixed slurry; add absolute ethanol at a liquid-solid ratio of 0.8 L / kg, and the ultrasonic power is 4.5 kW; the extra-coarse tungsten carbide powder and the slurry obtained in step S2 are added to the ultrasonic mixer simultaneously, wherein the feeding speed of the extra-coarse tungsten carbide powder is 2.0 kg / min, and the feeding speed of the slurry is 0.2 kg / min. After the feeding is completed, continue to mix for 1 h; S4. Secondary ball milling: Add the mixed slurry into a ball mill, adjust the liquid-solid ratio to 0.28 L / kg, and perform secondary ball milling. The ball-to-material ratio is 1:1, the ball milling time is 3 h, and the rotation speed of the ball mill is 36 r / min; after the ball milling is completed, obtain the final slurry product.

[0040] The final slurry product is spray-dried and then used for pressing and sintering to obtain cemented carbide, as Figure 1 shown.

[0041] Example 2 A ball milling process for extra-coarse cemented carbide includes the following steps: S1. Batching: According to the composition of cemented carbide, weigh extra-coarse tungsten carbide powder, binder, and additive as raw materials for batching, and reserve the molding agent; by weight percentage, the raw materials are: 93.5 wt% of extra-coarse tungsten carbide powder, 6 wt% of binder, and 0.5 wt% of additive; the molding agent is added separately at 2 wt% of the total weight of the raw materials. The average Fsss particle size of the extra-coarse tungsten carbide powder is 20 μm, the average Fsss particle size of the binder is 100 nm, and the average Fsss particle size of the additive is 1.0 μm. The additive is a mixture of chromium carbide and tantalum carbide with a mass ratio of 3:2, the binder is cobalt powder, and the molding agent is paraffin; S2. Primary ball milling: Add the binder, additive, and forming agent into a ball mill, then add oleic acid and absolute ethanol for primary ball milling. After the ball milling is completed, take out the slurry for standby; add oleic acid at a liquid-solid ratio of 1.5 mL / kg, add absolute ethanol at a liquid-solid ratio of 0.26 L / kg, the ball-to-material ratio is 2:1, the ball milling time is 5 h, and the rotational speed of the ball mill is 38 r / min; S3. Ultrasonic mixing: Take absolute ethanol, the slurry obtained in step S2, and ultra-coarse tungsten carbide powder and add them into an ultrasonic mixer for ultrasonic mixing. After the mixing is completed, a mixed slurry is obtained; add absolute ethanol at a liquid-solid ratio of 0.8 L / kg, and the ultrasonic power is 4.0 kW; the ultra-coarse tungsten carbide powder and the slurry obtained in step S2 are added into the ultrasonic mixer simultaneously. Among them, the feeding speed of the ultra-coarse tungsten carbide powder is 2.0 kg / min, and the feeding speed of the slurry is 0.2 kg / min. After the feeding is completed, continue to mix for 1 h; S4. Secondary ball milling: Add the mixed slurry into a ball mill, adjust the liquid-solid ratio to 0.28 L / kg, and perform secondary ball milling. The ball-to-material ratio is 1:1, the ball milling time is 3 h, and the rotational speed of the ball mill is 36 r / min; After the ball milling is completed, the final slurry product is obtained.

[0042] The final slurry product is spray-dried and then used for pressing and sintering to obtain cemented carbide, as Figure 2 shown.

[0043] Example 3 A ball milling process for ultra-coarse cemented carbide includes the following steps: S1. Batching: According to the composition of the cemented carbide, weigh ultra-coarse tungsten carbide powder and binder as raw materials for batching, and take the forming agent for standby; by weight percentage, the raw materials are: 94 wt% of ultra-coarse tungsten carbide powder and 6 wt% of binder; the forming agent is added separately at 2 wt% of the total weight of the raw materials. The average Fsss particle size of the ultra-coarse tungsten carbide powder is 20 μm, the average Fsss particle size of the binder is 100 nm, the binder is cobalt powder, and the forming agent is paraffin; S2. Primary ball milling: Add the binder and forming agent into a ball mill, then add oleic acid and absolute ethanol for primary ball milling. After the ball milling is completed, take out the slurry for standby; add oleic acid at a liquid-solid ratio of 1.5 mL / kg, add absolute ethanol at a liquid-solid ratio of 0.26 L / kg, the ball-to-material ratio is 2:1, the ball milling time is 6 h, and the rotational speed of the ball mill is 38 r / min; S3. Ultrasonic mixing: Add anhydrous ethanol, the slurry obtained in step S2, and ultra-coarse tungsten carbide powder into an ultrasonic mixer for ultrasonic mixing. After mixing, a mixed slurry is obtained. Add anhydrous ethanol at a liquid-solid ratio of 0.8 L / kg, and the ultrasonic power is 4.0 kW. The ultra-coarse tungsten carbide powder and the slurry obtained in step S2 are added to the ultrasonic mixer simultaneously. Among them, the feeding speed of the ultra-coarse tungsten carbide powder is 2.0 kg / min, and the feeding speed of the slurry is 0.2 kg / min. After feeding, continue to mix for 1 h; S4. Secondary ball milling: Add the mixed slurry into a ball mill, adjust the liquid-solid ratio to 0.28 L / kg, perform secondary ball milling, the ball-to-material ratio is 1:1, the ball milling time is 3 h, and the rotational speed of the ball mill is 36 r / min; After ball milling, the final slurry product is obtained.

[0044] The final slurry product is spray-dried and then used for pressing and sintering to obtain cemented carbide, as Figure 3 shown.

[0045] Comparative Example 1 The process steps of this comparative example are as follows: S1. Batching: According to the composition of the cemented carbide, weigh ultra-coarse tungsten carbide powder, binder, and additive as raw materials for batching, and reserve the molding agent; By weight percentage, the raw materials are: 93.7 wt% of ultra-coarse tungsten carbide powder, 6 wt% of binder, and 0.3 wt% of additive; The molding agent is added separately at 2 wt% of the total weight of the raw materials. The average Fsss particle size of the ultra-coarse tungsten carbide powder is 20 μm, the average Fsss particle size of the binder is 100 nm, and the average Fsss particle size of the additive is 1.0 μm. The additive is tantalum carbide powder, the binder is cobalt powder, and the molding agent is paraffin; S2. Ball milling: Add the ultra-coarse tungsten carbide powder, cobalt powder, tantalum carbide powder, and paraffin in step 1 into a ball mill, then add oleic acid at a liquid-solid ratio of 1.5 mL / kg, and then add anhydrous ethanol at a liquid-solid ratio of 0.26 L / kg. Ball mill in the ball mill at a ball-to-material ratio of 2:1 for 8 h, and the rotational speed of the ball mill is 36 r / min to obtain a slurry.

[0046] The slurry is spray-dried and then used for pressing and sintering to obtain cemented carbide, as Figure 4 shown.

[0047] Comparative Example 2 The process steps of this comparative example are as follows: S1. Ingredients: According to the composition of cemented carbide, weigh extra-coarse tungsten carbide powder, binder, and additive as raw materials for ingredient preparation, and reserve the molding agent; by weight percentage, the raw materials are: 93.5 wt% of extra-coarse tungsten carbide powder, 6 wt% of binder, and 0.5 wt% of additive; the molding agent is added separately at 2 wt% of the total weight of the raw materials. The average Fsss particle size of the extra-coarse tungsten carbide powder is 20 μm, the average Fsss particle size of the binder is 100 nm, and the average Fsss particle size of the additive is 1.0 μm. The additive is chromium carbide and tantalum carbide with a mass ratio of 3:2, the binder is cobalt powder, and the molding agent is paraffin; S2. Ball milling: Add the extra-coarse tungsten carbide powder, cobalt powder, tantalum carbide powder, chromium carbide powder, and paraffin from Step 1 into a ball mill, then add oleic acid according to a liquid-solid ratio of 1.5 mL / kg, and add absolute ethanol according to a liquid-solid ratio of 0.26 L / kg. Ball mill in the ball mill at a ball-to-material ratio of 2:1 for 8 h, and the rotation speed of the ball mill is 36 r / min to obtain a slurry.

[0048] The slurry is used for pressing and sintering to obtain cemented carbide after spray drying, as Figure 5 shown.

[0049] Comparative Example 3 The process steps of this comparative example are as follows: S1. Ingredients: According to the composition of cemented carbide, weigh extra-coarse tungsten carbide powder and binder as raw materials for ingredient preparation, and reserve the molding agent; by weight percentage, the raw materials are: 94 wt% of extra-coarse tungsten carbide powder and 6 wt% of binder; the molding agent is added separately at 2 wt% of the total weight of the raw materials. The average Fsss particle size of the extra-coarse tungsten carbide powder is 20 μm, the average Fsss particle size of the binder is 100 nm, the binder is cobalt powder, and the molding agent is paraffin; S2. Ball milling: Add the extra-coarse tungsten carbide powder, cobalt powder, and paraffin from Step 1 into a ball mill, then add oleic acid according to a liquid-solid ratio of 1.5 mL / kg, and add absolute ethanol according to a liquid-solid ratio of 0.26 L / kg. Ball mill in the ball mill at a ball-to-material ratio of 2:1 for 8 h, and the rotation speed of the ball mill is 36 r / min to obtain a slurry.

[0050] The slurry is used for pressing and sintering to obtain cemented carbide after spray drying, as Figure 6 shown.

[0051] Comparative Example 4 The difference from Example 3 is that the average Fsss particle size of the cobalt powder is 0.9 μm.

[0052] The slurry prepared by this comparative example is used for pressing and sintering to obtain cemented carbide after spray drying, as Figure 7 shown.

[0053] Comparative Example 5 The difference from Example 3 is that the average Fsss particle size of the cobalt powder is 1.1 μm.

[0054] The slurry prepared by this comparative example is spray-dried and then used for pressing and sintering to obtain cemented carbide, as Figure 8 shown.

[0055] Comparative Example 6 The difference from Example 3 is that the ultrasonic power is 1.5 kW.

[0056] The slurry prepared by this comparative example is spray-dried and then used for pressing and sintering to obtain cemented carbide, as Figure 9 shown.

[0057] The above-mentioned examples and comparative examples were subjected to vacuum sintering in the same furnace and the same area, and metallographic inspection was carried out after sintering (see Figures 1-9 ), and the results are shown in Table 1: Table 1 Test Results It can be seen from the above examples and comparative examples that the examples of the method of the present invention can effectively reduce the problems of porosity and uneven components such as cobalt aggregation, additive segregation, and coarse crystal aggregation while ensuring the integrity of tungsten carbide.

[0058] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structural transformation made using the content of the specification of the present invention under the inventive concept of the present invention, or direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A ball milling process for ultra-coarse cemented carbide, characterized in that: The process comprises the following steps: S1. Batching: According to the composition of cemented carbide, weigh the ultra-coarse tungsten carbide powder, binder, and additives as raw materials for batching, and take the molding agent for standby; S2, primary ball milling: adding the binder, additives and forming agent into the ball mill, and then adding oleic acid and anhydrous ethanol for primary ball milling. After the ball milling, the slurry is taken out for use; S3, ultrasonic mixing: adding anhydrous ethanol, the slurry obtained in step S2 and the ultra-coarse tungsten carbide powder into an ultrasonic mixer for ultrasonic mixing, and obtaining a mixed slurry after the mixing is completed; S4, secondary ball milling: after the anhydrous ethanol in the mixed slurry is recovered, the mixed slurry is added into a ball mill for secondary ball milling, and the final slurry product is obtained after the ball milling is completed.

2. The ball milling process of ultra-coarse cemented carbide according to claim 1, characterized in that: In the step S1, the raw materials are, by weight percentage, 93.5-94 wt % of ultra-coarse tungsten carbide powder, 5.5-6.5 wt % of binder, and 0-0.5 wt % of additive.

3. The ball milling process of ultra-coarse cemented carbide according to claim 2, characterized in that: In the step S1, the molding agent is added separately at 2 wt % of the total weight of the raw materials.

4. The ball milling process of ultra-coarse cemented carbide according to claim 2, characterized in that: In the step S1, the average Fsss particle size of the ultra-coarse tungsten carbide powder is 17-23 μm, the average Fsss particle size of the binder is 80-120 nm, and the average Fsss particle size of the additive is 0.8-1.2 μm.

5. The ball milling process of ultra-coarse cemented carbide according to claim 2, characterized in that: In the step S1, the additive is a metal carbide other than tungsten, including at least one of chromium carbide, tantalum carbide, titanium carbide and niobium carbide.

6. The ball milling process of ultra-coarse cemented carbide according to claim 2, characterized in that: In the step S1, the binder is cobalt powder, and the molding agent is paraffin.

7. The ball milling process of ultra-coarse cemented carbide according to claim 1, characterized in that: In step S2, during the first ball milling process, oleic acid is added at a liquid-solid ratio of 1.4-1.6 mL / kg, anhydrous ethanol is added at a liquid-solid ratio of 0.26-0.28 L / kg, the ball-to-material ratio is (1.5-3):1, the ball milling time is 5-6 h, and the ball mill speed is 36-38 r / min.

8. The ball milling process of ultra-coarse cemented carbide according to claim 1, characterized in that: In the step S3, anhydrous ethanol is added at a liquid-to-solid ratio of 0.6-0.8 L / kg, and the ultrasonic power is 3.0-5.0 kW.

9. The ball milling process of ultra-coarse cemented carbide according to claim 1, characterized in that: In the step S3, the ultra-coarse tungsten carbide powder and the slurry obtained in the step S2 are simultaneously added to the ultrasonic mixer, wherein the feeding rate of the ultra-coarse tungsten carbide powder is 1.8-2.2 kg / min, and the feeding rate of the slurry is 0.18-0.22 kg / min.

10. The ball milling process of ultra-coarse cemented carbide according to claim 1, characterized in that: In the step S4, during the secondary ball milling process, the liquid-to-solid ratio is 0.25-0.30 L / kg, the ball-to-material ratio is (1.0-2.0):1, the ball milling time is 2-6 h, and the ball mill speed is 36-38 r / min.

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