High-performance super-coarse hard alloy material and preparation method thereof

Abstract

The invention relates to the technical field of hard alloy materials, in particular to a high-performance super-coarse hard alloy material and a preparation method thereof.The super-coarse hard alloy material comprises 90-92 parts of WC powder, 9-10 parts of Co powder, 1-3 parts of a forming agent and 20-25 parts of an auxiliary additive. According to the ultra-coarse hard alloy material, the WC powder, the Co powder, the forming agent and other raw materials are blended, meanwhile, the functional agent and the modifier are added as synergistic raw materials, the performance effect of a product is further enhanced, and therefore the density and hardness of the obtained ultra-coarse hard alloy material and the thermal fatigue resistance and abrasion resistance of the product are excellent; and the comprehensive coordination effect of the product is obvious.

Description

Technical Field

[0001] This invention relates to the field of cemented carbide materials technology, specifically to a high-performance ultra-coarse cemented carbide material and its preparation method. Background Technology

[0002] Ultra-coarse-grained cemented carbide, due to its excellent wear resistance, high strength, and good toughness, is widely used in machining, mining, and oil drilling. However, with the increasing demands for material performance in industry, existing ultra-coarse-grained cemented carbide products suffer from poor bending strength, low density, poor hardness, and poor thermal fatigue resistance. Furthermore, they exhibit poor wear resistance and overall poor performance, limiting their efficiency. Therefore, this invention provides further improvements. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this invention is to provide a high-performance ultra-coarse cemented carbide material and its preparation method, so as to solve the problems mentioned in the background art.

[0004] The present invention solves the technical problem by adopting the following technical solution: This invention provides a high-performance ultra-coarse cemented carbide material, which comprises 90-92 parts of WC powder, 9-10 parts of Co powder, 1-3 parts of forming agent, and 20-25 parts of auxiliary additives. The auxiliary additive is prepared by oleic acid and anhydrous ethanol in a weight ratio of 2:5. The Co powder is cobalt powder with a particle size of 1.0-1.5 μm, the forming agent is paraffin wax, and the WC powder has a particle size of 30-35 μm.

[0005] Preferably, the ultra-coarse cemented carbide material further contains 5-8 parts of functional agent and 4-7 parts of modifier; The preparation method of the functional agent is as follows: S01: Mix 3-5 parts of carbon nanotubes, 2-5 parts of 85% ethanol aqueous solution and 1-2 parts of silane coupling agent KH550 evenly to obtain carbon nanotube liquid. S02: Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water and adjust the pH to obtain a buffer solution. The concentration of tris(hydroxymethyl)aminomethane hydrochloride in the buffer solution is 1-2 mg / mL, and the pH of the buffer solution is 8-11. S03: Add 2-3 parts sodium alginate solution and 1-2 parts buffer solution to 5-8 parts β-cyclodextrin, stir and treat to obtain modified β-cyclodextrin solution; 2-3 parts of carbon nanotube liquid and 5-8 parts of modified β-cyclodextrin liquid are thoroughly mixed to obtain a carbon nanotube-based blended solution. S04: 3-5 parts of nano-titanium carbide, 2-3 parts of graphene and 2-4 parts of boron nitride are blended and sintered for 1 hour. After sintering, a sintered body is obtained. The nano-carbon nanotube-based blending liquid and the sintered body are then blended and ball-milled for 2 hours at a speed of 1200-1500 r / min. After ball milling, the mixture is filtered and dried to obtain the functional agent.

[0006] Preferably, the sintering temperature of the blending sintering is 210-220℃, and the mass fraction of the sodium alginate solution is 4-7%.

[0007] Preferably, the stirring speed in S03 is 150-200 r / min, the stirring time is 20-30 min, and the stirring temperature is 50-55℃.

[0008] Preferably, the method for preparing the modifier is as follows: S11: Prepare a urea solution with a mass fraction of 2-5% and a lanthanum chloride solution with a mass fraction of 4-7%; mix 1-2 parts of nano-silica sol, 5-8 parts of urea solution and 2-3 parts of nickel sulfate evenly, then add 2-3 parts of lanthanum chloride solution and stir evenly to obtain nickel sulfate solution. S12: Mix chromium carbide body and nickel sulfate solution at a weight ratio of (3-5):7 to obtain nickel sulfate-chromium carbide composite agent; then, treat the nickel sulfate-chromium carbide composite agent and the lubricating material at a weight ratio of (11-15):5 to improve lubrication. After lubrication, filter and dry to obtain the modifier.

[0009] Preferably, the chromium carbide body is obtained by blending chromium carbide, yttrium oxide and molybdenum disulfide in a weight ratio of (3-5):2:(1-2) and sintering for 1 hour at a sintering temperature of 150-170℃.

[0010] Preferably, the finishing and improving treatment is performed by ball milling, first at a speed of 1050-1150 r / min for 1 hour, and then at a speed of 450-550 r / min for 2 hours.

[0011] Preferably, the method for preparing the repairing agent is as follows: Mix 3-5 parts of aluminum silicate fiber, 5-8 parts of sodium silicate solution and 1-2 parts of nano diamond evenly, then add 2-4 parts of silica powder and 1-2 parts of citric acid, sonicate, filter and dry to obtain the repair material.

[0012] Preferably, the sodium silicate solution has a mass fraction of 2-5%; the ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment lasts for 1 hour.

[0013] This invention also provides a method for preparing high-performance ultra-coarse cemented carbide materials, comprising the following steps: The raw materials were weighed according to the weight proportions, and the raw materials were wet ball milled for 12 hours. Then, they were spray granulated and sintered. The sintering temperature was 1440-1460℃, the sintering pressure was 5MPa, and the sintering time was 1-2 hours to obtain the ultra-coarse cemented carbide material of the present invention.

[0014] The high strength / high toughness of carbon nanotubes and graphene in the functional agents are uniformly distributed in the alloy matrix through dispersion modification of the β-cyclodextrin-sodium alginate composite system, forming a "rigid support-flexible bridging" structure, which effectively hinders crack propagation; the grain refinement and interface optimization of the modifier: yttrium oxide (Y2O3) in the modifier acts as a grain refiner to avoid abnormal grain growth and refine the number of grain boundaries; molybdenum disulfide (MoS2) modifies the WC-Co interface bonding state, reduces interface defects (such as pores and oxide phases), and improves stress transfer efficiency.

[0015] WC powder itself possesses a high hardness base. The functional agent nano-titanium carbide and the modifier chromium carbide, together with nano-diamond, form a composite hard system of "ultra-coarse WC + ultra-fine hard phase," which synergistically enhances hardness. The densification effect of dispersion and sintering processes: The auxiliary additive (oleic acid: anhydrous ethanol = 2:5) acts as a dispersant, which can reduce the probability of raw material agglomeration during wet ball milling. After spray granulation, the particles have excellent flowability. Combined with high-pressure sintering at 1440-1460℃, it promotes diffusion and bonding between particles, reduces closed pores and porosity defects, and improves density. The interface filling of the modifier: The composite phase formed by nickel sulfate, lanthanum chloride, and nano-silica sol can fill the gaps at the WC-Co interface, optimize the interface bonding state, and further improve density and hardness uniformity. Both boron nitride and graphene in the functional agents have high thermal conductivity, which can quickly conduct heat at high temperatures and reduce thermal stress concentration; chromium carbide and yttrium oxide in the modifiers can form a dense oxide film (Cr2O3, Y2O3), which hinders oxygen diffusion into the alloy and improves oxidation resistance; aluminum silicate fiber in the lubricant has excellent high-temperature stability and can enhance the high-temperature structural stability of the alloy; molybdenum disulfide (MoS2) can still maintain solid lubrication properties at high temperatures, reducing high-temperature friction and wear; yttrium oxide (Y2O3) refines grains, reduces grain boundary hot corrosion channels, and high-pressure sintering reduces defects such as porosity, thus reducing the probability of crack initiation at high temperatures; The ultra-coarse WC grains + TiC + Cr3C2 + nanodiamond form a "gradient wear-resistant system" that can resist different types of wear (abrasive wear, adhesive wear); molybdenum disulfide (MoS2) in the modifier is a solid lubricant that can reduce the coefficient of friction and reduce adhesive wear; the β-cyclodextrin-sodium alginate modification system in the functional agent improves the dispersibility of nanoparticles and avoids the agglomeration of hard phases that leads to increased local wear; this invention achieves a five-fold synergy of "high hardness + high bending strength + high toughness + high heat resistance + high wear resistance" through component synergy and process optimization. The comprehensive performance indicators are superior to existing products, and it can meet the needs of use under multiple working conditions and complex loads (such as simultaneous impact, etc.). High-temperature and wear-prone oil drill bits and mining pick teeth); synergistic division of labor between functional agents and modifiers: functional agents focus on improving "strength-toughness-heat resistance" (synergy of carbon nanotubes, graphene, and BN), while modifiers focus on optimizing "hardness-wear resistance-density" (synergy of Cr3C2, nanodiamond, and MoS2). Performance complementarity is achieved through interfacial bonding improvement; the nano-components (carbon nanotubes, graphene, nanodiamond, etc.) in functional agents and modifiers are modified by β-cyclodextrin, sodium alginate, silane coupling agents, etc., to avoid agglomeration and achieve "nanoscale dispersion + macroscopic density", which not only brings out the excellent performance of nanomaterials, but also ensures the macroscopic structural stability of the alloy.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The ultra-coarse cemented carbide material of this invention is made by blending raw materials such as WC powder, Co powder and forming agent, and adding functional agents and modifiers as co-forming materials to further enhance the performance of the product. As a result, the ultra-coarse cemented carbide material has excellent density, hardness, thermal fatigue resistance and wear resistance, and the overall coordination effect of the product is significant. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to specific examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] This embodiment provides a high-performance ultra-coarse cemented carbide material, which comprises 90-92 parts of WC powder, 9-10 parts of Co powder, 1-3 parts of forming agent, and 20-25 parts of auxiliary additives. The auxiliary additive is prepared by oleic acid and anhydrous ethanol in a weight ratio of 2:5. The Co powder is cobalt powder with a particle size of 1.0-1.5 μm, the forming agent is paraffin wax, and the WC powder has a particle size of 30-35 μm.

[0019] The ultra-coarse cemented carbide material in this embodiment also contains 5-8 parts of functional agent and 4-7 parts of modifier; The preparation method of the functional agent is as follows: S01: Mix 3-5 parts of carbon nanotubes, 2-5 parts of 85% ethanol aqueous solution and 1-2 parts of silane coupling agent KH550 evenly to obtain carbon nanotube liquid. S02: Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water and adjust the pH to obtain a buffer solution. The concentration of tris(hydroxymethyl)aminomethane hydrochloride in the buffer solution is 1-2 mg / mL, and the pH of the buffer solution is 8-11. S03: Add 2-3 parts sodium alginate solution and 1-2 parts buffer solution to 5-8 parts β-cyclodextrin, stir and treat to obtain modified β-cyclodextrin solution; 2-3 parts of carbon nanotube liquid and 5-8 parts of modified β-cyclodextrin liquid are thoroughly mixed to obtain a carbon nanotube-based blended solution. S04: 3-5 parts of nano-titanium carbide, 2-3 parts of graphene and 2-4 parts of boron nitride are blended and sintered for 1 hour. After sintering, a sintered body is obtained. The nano-carbon nanotube-based blending liquid and the sintered body are then blended and ball-milled for 2 hours at a speed of 1200-1500 r / min. After ball milling, the mixture is filtered and dried to obtain the functional agent.

[0020] In this embodiment, the sintering temperature for blending is 210-220℃, and the mass fraction of sodium alginate solution is 4-7%.

[0021] In this embodiment, the stirring speed in S03 is 150-200 r / min, the stirring time is 20-30 min, and the stirring temperature is 50-55℃.

[0022] The preparation method of the modifier in this embodiment is as follows: S11: Prepare a urea solution with a mass fraction of 2-5% and a lanthanum chloride solution with a mass fraction of 4-7%; mix 1-2 parts of nano-silica sol, 5-8 parts of urea solution and 2-3 parts of nickel sulfate evenly, then add 2-3 parts of lanthanum chloride solution and stir evenly to obtain nickel sulfate solution. S12: Mix chromium carbide body and nickel sulfate solution at a weight ratio of (3-5):7 to obtain nickel sulfate-chromium carbide composite agent; then, treat the nickel sulfate-chromium carbide composite agent and the lubricating material at a weight ratio of (11-15):5 to improve lubrication. After lubrication, filter and dry to obtain the modifier.

[0023] In this embodiment, the chromium carbide body is obtained by blending chromium carbide, yttrium oxide and molybdenum disulfide in a weight ratio of (3-5):2:(1-2) and sintering for 1 hour at a sintering temperature of 150-170°C.

[0024] In this embodiment, the finishing and improvement treatment is carried out by ball milling. First, the ball milling is carried out at a speed of 1050-1150 r / min for 1 hour, and then at a speed of 450-550 r / min for 2 hours.

[0025] The preparation method of the repairing agent in this embodiment is as follows: Mix 3-5 parts of aluminum silicate fiber, 5-8 parts of sodium silicate solution and 1-2 parts of nano diamond evenly, then add 2-4 parts of silica powder and 1-2 parts of citric acid, sonicate, filter and dry to obtain the repair material.

[0026] In this embodiment, the sodium silicate solution has a mass fraction of 2-5%; the ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment lasts for 1 hour.

[0027] This embodiment describes a method for preparing a high-performance, ultra-coarse cemented carbide material, comprising the following steps: The raw materials were weighed according to the weight proportions, and the raw materials were wet ball milled for 12 hours. Then, they were spray granulated and sintered. The sintering temperature was 1440-1460℃, the sintering pressure was 5MPa, and the sintering time was 1-2 hours to obtain the ultra-coarse cemented carbide material of the present invention.

[0028] Example 1. This embodiment provides a high-performance ultra-coarse cemented carbide material, which includes 90 parts of WC powder, 9 parts of Co powder, 1 part of forming agent, and 20 parts of auxiliary additives. The auxiliary additive is prepared by oleic acid and anhydrous ethanol in a weight ratio of 2:5. The Co powder is cobalt powder with a particle size of 1.0 μm, the forming agent is paraffin wax, and the WC powder has a particle size of 30 μm.

[0029] The ultra-coarse cemented carbide material in this embodiment also contains 5 parts functional agent and 4 parts modifier; The preparation method of the functional agent is as follows: S01: Mix 3 parts of carbon nanotubes, 2 parts of 85% ethanol aqueous solution and 1 part of silane coupling agent KH550 evenly to obtain carbon nanotube liquid. S02: Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water and adjust the pH to obtain a buffer solution. The concentration of tris(hydroxymethyl)aminomethane hydrochloride in the buffer solution is 1 mg / mL, and the pH of the buffer solution is 8. S03: Add 2 parts sodium alginate solution and 1 part buffer solution to 5 parts β-cyclodextrin, stir and treat to obtain modified β-cyclodextrin solution; Two parts of carbon nanotube liquid and five parts of modified β-cyclodextrin liquid were thoroughly mixed to obtain a carbon nanotube-based blended solution. S04: 3 parts of nano-titanium carbide, 2 parts of graphene and 2 parts of boron nitride were blended and sintered for 1 hour. After sintering, a sintered body was obtained. The nano-carbon nanotube-based blended liquid and the sintered body were then ball-milled for 2 hours at a speed of 1200 r / min. After ball milling, the mixture was filtered and dried to obtain the functional agent.

[0030] In this embodiment, the sintering temperature for blending is 210°C, and the mass fraction of sodium alginate solution is 4%.

[0031] In this embodiment, the stirring speed in S03 is 150 r / min, the stirring time is 20 min, and the stirring temperature is 50℃.

[0032] The preparation method of the modifier in this embodiment is as follows: S11: Prepare a urea solution with a mass fraction of 2% and a lanthanum chloride solution with a mass fraction of 4%; mix 1 part of nano silica sol, 5 parts of urea solution and 2 parts of nickel sulfate evenly, then add 2 parts of lanthanum chloride solution and stir evenly to obtain nickel sulfate solution; S12: Chromium carbide body and nickel sulfate solution are stirred thoroughly at a weight ratio of 3:7 to obtain nickel sulfate-chromium carbide composite agent; then, nickel sulfate-chromium carbide composite agent and lubricating material are lubricated and improved at a weight ratio of 11:5. After lubrication is completed, the mixture is filtered and dried to obtain the modifier.

[0033] In this embodiment, the chromium carbide body is obtained by blending chromium carbide, yttrium oxide and molybdenum disulfide in a weight ratio of 3:2:1 and sintering for 1 hour at a sintering temperature of 150°C.

[0034] In this embodiment, the finishing and improvement treatment is carried out by ball milling. First, the ball milling is carried out at a speed of 1050 r / min for 1 hour, and then at a speed of 450 r / min for 2 hours.

[0035] The preparation method of the repairing agent in this embodiment is as follows: Three parts of aluminum silicate fiber, five parts of sodium silicate solution and one part of nano diamond were mixed evenly, then two parts of silica powder and one part of citric acid were added, ultrasonically treated, filtered and dried to obtain the repair material.

[0036] In this embodiment, the sodium silicate solution has a mass fraction of 2%; the ultrasonic power of the ultrasonic treatment is 350W, and the ultrasonic treatment lasts for 1 hour.

[0037] This embodiment describes a method for preparing a high-performance, ultra-coarse cemented carbide material, comprising the following steps: The raw materials were weighed according to the weight proportions, and the raw materials were wet ball milled for 12 hours. Then, they were spray granulated and sintered at a temperature of 1440℃ and a pressure of 5MPa for 1 hour to obtain the ultra-coarse cemented carbide material of the present invention.

[0038] Example 2. This embodiment provides a high-performance ultra-coarse cemented carbide material, which includes 92 parts of WC powder, 10 parts of Co powder, 3 parts of forming agent, and 25 parts of auxiliary additives. The auxiliary additive is prepared by oleic acid and anhydrous ethanol in a weight ratio of 2:5. The Co powder is cobalt powder with a particle size of 1.5 μm, the forming agent is paraffin wax, and the WC powder has a particle size of 35 μm.

[0039] The ultra-coarse cemented carbide material in this embodiment also contains 8 parts functional agent and 7 parts modifier; The preparation method of the functional agent is as follows: S01: Mix 5 parts of carbon nanotubes, 5 parts of 85% ethanol aqueous solution and 2 parts of silane coupling agent KH550 evenly to obtain carbon nanotube liquid. S02: Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water and adjust the pH to obtain a buffer solution. The concentration of tris(hydroxymethyl)aminomethane hydrochloride in the buffer solution is 2 mg / mL, and the pH of the buffer solution is 11. S03: Add 3 parts sodium alginate solution and 2 parts buffer solution to 8 parts β-cyclodextrin, stir and treat to obtain modified β-cyclodextrin solution; Three parts of carbon nanotube liquid and eight parts of modified β-cyclodextrin liquid were thoroughly mixed to obtain a carbon nanotube-based blended liquid. S04: 5 parts of nano-titanium carbide, 3 parts of graphene and 4 parts of boron nitride were blended and sintered for 1 hour. After sintering, a sintered body was obtained. The nano-carbon nanotube-based blending liquid and the sintered body were then blended and ball-milled for 2 hours at a speed of 1500 r / min. After ball milling, the mixture was filtered and dried to obtain the functional agent.

[0040] In this embodiment, the sintering temperature for blending is 220°C, and the mass fraction of the sodium alginate solution is 7%.

[0041] In this embodiment, the stirring speed in S03 is 200 r / min, the stirring time is 30 min, and the stirring temperature is 55℃.

[0042] The preparation method of the modifier in this embodiment is as follows: S11: Prepare a 5% urea solution and a 7% lanthanum chloride solution; mix 2 parts of nano-silica sol, 8 parts of urea solution and 3 parts of nickel sulfate evenly, then add 3 parts of lanthanum chloride solution and stir evenly to obtain nickel sulfate solution. S12: Chromium carbide body and nickel sulfate solution are stirred thoroughly at a weight ratio of 5:7 to obtain nickel sulfate-chromium carbide composite agent; then, nickel sulfate-chromium carbide composite agent and lubricating material are lubricated and improved at a weight ratio of 15:5. After lubrication is completed, the mixture is filtered and dried to obtain the modifier.

[0043] In this embodiment, the chromium carbide body is obtained by blending chromium carbide, yttrium oxide and molybdenum disulfide in a weight ratio of 5:2:2 and sintering for 1 hour at a sintering temperature of 170°C.

[0044] In this embodiment, the finishing and improvement treatment is carried out by ball milling. First, the ball milling is carried out at a speed of 1150 r / min for 1 hour, and then at a speed of 550 r / min for 2 hours.

[0045] The preparation method of the repairing agent in this embodiment is as follows: Five parts of aluminum silicate fiber, eight parts of sodium silicate solution and two parts of nano diamond were mixed evenly, then four parts of silica powder and two parts of citric acid were added, ultrasonically treated, filtered and dried to obtain the repair material.

[0046] In this embodiment, the sodium silicate solution has a mass fraction of 5%; the ultrasonic power of the ultrasonic treatment is 400W, and the ultrasonic treatment lasts for 1 hour.

[0047] This embodiment describes a method for preparing a high-performance, ultra-coarse cemented carbide material, comprising the following steps: The raw materials were weighed according to the weight proportions, and the raw materials were wet ball milled for 12 hours. Then, they were spray granulated and sintered at a temperature of 1460℃ and a pressure of 5MPa for 2 hours to obtain the ultra-coarse cemented carbide material of the present invention.

[0048] Example 3. This embodiment describes a high-performance ultra-coarse cemented carbide material, comprising 91 parts WC powder, 9.5 parts Co powder, 2 parts forming agent, and 22.5 parts auxiliary additives. The auxiliary additive is prepared by oleic acid and anhydrous ethanol in a weight ratio of 2:5. The Co powder is cobalt powder with a particle size of 1.25 μm, the forming agent is paraffin wax, and the WC powder has a particle size of 32.5 μm.

[0049] The ultra-coarse cemented carbide material in this embodiment also contains 6.5 parts of functional agent and 5.5 parts of modifier; The preparation method of the functional agent is as follows: S01: Mix 4 parts of carbon nanotubes, 3.5 parts of 85% ethanol aqueous solution and 1.5 parts of silane coupling agent KH550 evenly to obtain carbon nanotube liquid. S02: Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water and adjust the pH to obtain a buffer solution. The concentration of tris(hydroxymethyl)aminomethane hydrochloride in the buffer solution is 1.5 mg / mL, and the pH of the buffer solution is 9. S03: Add 2.5 parts sodium alginate solution and 1.5 parts buffer solution to 6.5 parts β-cyclodextrin, stir and treat to obtain modified β-cyclodextrin solution; 2.5 parts of carbon nanotube liquid and 6.5 parts of modified β-cyclodextrin liquid were thoroughly mixed to obtain a carbon nanotube-based blended solution. S04: 4 parts of nano-titanium carbide, 2.5 parts of graphene and 3 parts of boron nitride were blended and sintered for 1 hour. After sintering, a sintered body was obtained. The nano-carbon nanotube-based blending liquid and the sintered body were then blended and ball-milled for 2 hours at a speed of 1350 r / min. After ball milling, the mixture was filtered and dried to obtain the functional agent.

[0050] In this embodiment, the sintering temperature of the blend is 215°C, and the mass fraction of the sodium alginate solution is 5.5%.

[0051] In this embodiment, the stirring speed in S03 is 170 r / min, the stirring time is 25 min, and the stirring temperature is 52.5℃.

[0052] The preparation method of the modifier in this embodiment is as follows: S11: Prepare a urea solution with a mass fraction of 3.5% and a lanthanum chloride solution with a mass fraction of 5.5%; mix 1.5 nm silica sol, 6.5 parts of urea solution and 2.5 parts of nickel sulfate evenly, then add 2.5 parts of lanthanum chloride solution and stir evenly to obtain nickel sulfate solution; S12: Chromium carbide body and nickel sulfate solution are stirred thoroughly at a weight ratio of 4:7 to obtain nickel sulfate-chromium carbide composite agent; then, nickel sulfate-chromium carbide composite agent and lubricating material are lubricated and improved at a weight ratio of 13:5. After lubrication is completed, the mixture is filtered and dried to obtain the modifier.

[0053] In this embodiment, the chromium carbide body is obtained by blending chromium carbide, yttrium oxide and molybdenum disulfide in a weight ratio of 4:2:1.5 and sintering for 1 hour at a sintering temperature of 160°C.

[0054] In this embodiment, the finishing and improvement treatment is carried out by ball milling. First, the ball milling is carried out at a speed of 1100 r / min for 1 hour, and then at a speed of 500 r / min for 2 hours.

[0055] The preparation method of the repairing agent in this embodiment is as follows: Four parts of aluminum silicate fiber, 6.5 parts of sodium silicate solution and 1.5 parts of nano diamond were stirred evenly, and then three parts of silica powder and 1.5 parts of citric acid were added. The mixture was ultrasonically treated, filtered and dried to obtain the repair material.

[0056] In this embodiment, the sodium silicate solution has a mass fraction of 3.5%; the ultrasonic power of the ultrasonic treatment is 375W, and the ultrasonic treatment lasts for 1 hour.

[0057] This embodiment describes a method for preparing a high-performance, ultra-coarse cemented carbide material, comprising the following steps: The raw materials were weighed according to the weight proportions, and the raw materials were wet ball milled for 12 hours. Then, they were spray granulated and sintered at a temperature of 1450°C and a pressure of 5 MPa for 1.5 hours to obtain the ultra-coarse cemented carbide material of the present invention.

[0058] Comparative Example 1. Unlike Example 3, no functional agents were added.

[0059] Comparative Example 2. Unlike Example 3, the preparation method of the functional agent did not include the addition of a nano-carbon nanotube-based blending solution.

[0060] Comparative Example 3. Unlike Example 3, no carbon nanotube liquid was added in the preparation of the carbon nanotube-based blending solution.

[0061] Comparative Example 4. Unlike Example 3, no modified β-cyclodextrin solution was added in the preparation of the carbon nanotube-based blend.

[0062] Comparative Example 5. Unlike Example 3, no buffer solution was added to the modified β-cyclodextrin solution.

[0063] Comparative Example 6. Unlike Example 3, no sintered body was added to the functional agent.

[0064] Comparative Example 7. Unlike Example 3, no nano-titanium carbide or graphene was added to the sintered body.

[0065] Comparative Example 8. Unlike Example 3, no boron nitride was added to the sintered body.

[0066] Comparative Example 9. Unlike Example 3, no modifier was added.

[0067] Comparative Example 10. Unlike Example 3, no chromium carbide was added during the preparation of the modifier.

[0068] Comparative Example 11. Unlike Example 3, nickel sulfate solution was not added during the preparation of the modifier.

[0069] Comparative Example 12. Unlike Example 3, no wetting agent was added during the preparation of the modifier.

[0070] Comparative Example 13. Unlike Example 3, aluminum silicate fiber and silica powder were not added to the repair material.

[0071] Comparative Example 14. Unlike Example 3, nano-diamonds were not added to the repair material, and water was used instead of sodium silicate solution.

[0072] Examples 1-3 and Comparative Examples 1-14 were tested for flexural strength, density, hardness, wear resistance (load 50N, rotation speed 300r / min, time 2h) and thermal fatigue resistance (repeated hot and cold cycles until cracks appeared in the sample, cycling conditions: room temperature - 800℃ (holding for 30min) - room temperature (air cooling)). The performance test results are shown in Table 1 below. Table 1 is the comprehensive performance test result of the product. Table 1:

[0073]

[0074] As can be seen from Comparative Examples 1-14 and Examples 1-3; The product in Example 3 exhibits excellent flexural strength, density, hardness, wear resistance, and thermal fatigue resistance. The overall performance of the product is significantly improved, and its overall performance is coordinated and enhanced. As can be seen from Comparative Examples 1-14 and Example 3, the performance of the product deteriorates significantly when neither a functional agent nor a modifier is added. The performance of the product is significantly improved when both are blended and formulated. The preparation methods of the functional agents do not include nano-carbon nanotube-based blending solutions, nor do they include nano-carbon nanotube liquid, modified β-cyclodextrin liquid, or buffer solution. Furthermore, the functional agents do not include sintered bodies, nor do they contain nano-titanium carbide, graphene, or boron nitride. All of these methods result in varying degrees of performance degradation. The functional agents obtained using the specific method of this invention exhibit the most significant performance improvement. Additionally, the preparation of the sintered bodies is proprietary. Therefore, the technical solution of this invention provides the most significant performance improvement for the products. In the preparation of the modifier, chromium carbide, nickel sulfate solution, lubricant, aluminum silicate fiber and silica powder, and nanodiamond were not added. Furthermore, water was used instead of sodium silicate solution. All these methods resulted in a deterioration in product performance. Only the modifier prepared using the specific method of this invention exhibited the most significant performance improvement. In the preparation of the modifier, all raw materials are indispensable; only the specific raw material ratio of this invention can be used. Using other raw material ratios does not yield the same significant effect as this invention.

[0075] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0076] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A high-performance, ultra-coarse cemented carbide material, characterized in that, The ultra-coarse cemented carbide material comprises 90-92 parts of WC powder, 9-10 parts of Co powder, 1-3 parts of forming agent, and 20-25 parts of auxiliary additives. The auxiliary additive is prepared by oleic acid and anhydrous ethanol in a weight ratio of 2:

5. The Co powder is cobalt powder with a particle size of 1.0-1.5 μm, the forming agent is paraffin wax, and the WC powder has a particle size of 30-35 μm.

2. The high-performance ultra-coarse cemented carbide material according to claim 1, characterized in that, The ultra-coarse cemented carbide material also contains 5-8 parts of functional agents and 4-7 parts of modifiers; The preparation method of the functional agent is as follows: S01: Mix 3-5 parts of carbon nanotubes, 2-5 parts of 85% ethanol aqueous solution and 1-2 parts of silane coupling agent KH550 evenly to obtain carbon nanotube liquid. S02: Dissolve tris(hydroxymethyl)aminomethane hydrochloride in deionized water and adjust the pH to obtain a buffer solution. The concentration of tris(hydroxymethyl)aminomethane hydrochloride in the buffer solution is 1-2 mg / mL, and the pH of the buffer solution is 8-11. S03: Add 2-3 parts sodium alginate solution and 1-2 parts buffer solution to 5-8 parts β-cyclodextrin, stir and treat to obtain modified β-cyclodextrin solution; 2-3 parts of carbon nanotube liquid and 5-8 parts of modified β-cyclodextrin liquid are thoroughly mixed to obtain a carbon nanotube-based blended solution. S04: 3-5 parts of nano-titanium carbide, 2-3 parts of graphene and 2-4 parts of boron nitride are blended and sintered for 1 hour. After sintering, a sintered body is obtained. The nano-carbon nanotube-based blending liquid and the sintered body are then blended and ball-milled for 2 hours at a speed of 1200-1500 r / min. After ball milling, the mixture is filtered and dried to obtain the functional agent.

3. The high-performance ultra-coarse cemented carbide material according to claim 2, characterized in that, The sintering temperature of the blend is 210-220℃, and the mass fraction of the sodium alginate solution is 4-7%.

4. The high-performance ultra-coarse cemented carbide material according to claim 2, characterized in that, The stirring speed for the stirring process described in S03 is 150-200 r / min, the stirring time is 20-30 min, and the stirring temperature is 50-55℃.

5. The high-performance ultra-coarse cemented carbide material according to claim 1, characterized in that, The method for preparing the modifier is as follows: S11: Prepare a urea solution with a mass fraction of 2-5% and a lanthanum chloride solution with a mass fraction of 4-7%; mix 1-2 parts of nano-silica sol, 5-8 parts of urea solution and 2-3 parts of nickel sulfate evenly, then add 2-3 parts of lanthanum chloride solution and stir evenly to obtain nickel sulfate solution. S12: Mix chromium carbide body and nickel sulfate solution at a weight ratio of (3-5):7 to obtain nickel sulfate-chromium carbide composite agent; then, treat the nickel sulfate-chromium carbide composite agent and the lubricating material at a weight ratio of (11-15):5 to improve lubrication. After lubrication, filter and dry to obtain the modifier.

6. The high-performance ultra-coarse cemented carbide material according to claim 5, characterized in that, The chromium carbide body is obtained by blending chromium carbide, yttrium oxide and molybdenum disulfide in a weight ratio of (3-5):2:(1-2) and sintering for 1 hour at a sintering temperature of 150-170℃.

7. The high-performance ultra-coarse cemented carbide material according to claim 5, characterized in that, The repair and improvement treatment is carried out by ball milling. First, the ball milling is carried out at a speed of 1050-1150 r / min for 1 hour, and then at a speed of 450-550 r / min for 2 hours.

8. The high-performance ultra-coarse cemented carbide material according to claim 5, characterized in that, The preparation method of the repairing agent is as follows: Mix 3-5 parts of aluminum silicate fiber, 5-8 parts of sodium silicate solution and 1-2 parts of nano diamond evenly, then add 2-4 parts of silica powder and 1-2 parts of citric acid, sonicate, filter and dry to obtain the repair material.

9. The high-performance ultra-coarse cemented carbide material according to claim 8, characterized in that, The sodium silicate solution has a mass fraction of 2-5%; the ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment lasts for 1 hour.

10. A method for preparing a high-performance, ultra-coarse cemented carbide material as described in any one of claims 1 to 9, characterized in that, Includes the following steps: The raw materials were weighed according to the weight proportions, and the raw materials were wet ball milled for 12 hours. Then, they were spray granulated and sintered. The sintering temperature was 1440-1460℃, the sintering pressure was 5MPa, and the sintering time was 1-2 hours to obtain the ultra-coarse cemented carbide material of the present invention.

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