1805 results about "Tungsten carbide" patented technology

The invention belongs to the technical field of powder metallurgy, and particularly relates to high-performance tungsten carbide and a preparation method thereof. A preparation method of medium-coarse tungsten carbide comprises the following steps that tungsten oxide is subjected to high-temperature reduction through a reverse hydrogen reduction method, and tungsten powder is obtained; and the tungsten powder is subjected to carbon blending, uniform mixing and high-temperature carbonization in a reducing atmosphere, a product is pre-crushed and then subjected to airflow crushing, and the tungsten carbide is obtained. According to the preparation method of the medium-coarse tungsten carbide, the particle size of the prepared tungsten carbide is 1-3 microns, the total carbon content is 6.12-6.18%, the combined carbon content is larger than or equal to 6.10%, the free carbon content is smaller than or equal to 0.06%, the oxygen content is smaller than or equal to 0.12%, and the impurity content is smaller than 0.5%; the particle size distribution is narrow, the particles are uniform, and the performance of the tungsten carbide powder is greatly improved.

The invention relates to the technical field of ceramic materials, in particular to a wear-resistant woven ceramic material and a preparation method thereof, and the preparation method comprises the following steps: preparation of a ceramic body: weighing the following raw materials in parts by weight: 15-20 parts of boron nitride, 5-8 parts of aluminum oxide, 4-7 parts of an additive doped with modified nano titanium dioxide, 2-5 parts of tungsten carbide, 2-4 parts of zirconium oxide and 8-12 parts of ball-milling leveling liquid; according to the wear-resistant woven ceramic material disclosed by the invention, the carbon fibers and the basalt fibers are respectively immersed into the ceramic body for immersion treatment, then orthogonal weaving is performed, and finally sintering improvement is performed to obtain the woven ceramic material, so that the wear resistance, toughness and pollution resistance of the obtained woven ceramic material are improved in a balanced manner, and the product is excellent in ultraviolet resistance and thermal cycling resistance stability.

The invention discloses a high-entropy alloy bonding phase SiC hard composite material and a preparation method thereof, the SiC hard alloy composite material is a double-phase composite material and comprises SiC and high-entropy alloy, and the high-entropy alloy is AlMnCuiFeTi and AlZnCuFeTi. The proportion of the raw materials is 5 wt.%-20 wt.%. And the size of the SiC particles is 200 [mu] m. During preparation, firstly, the high-entropy alloy is prepared through mechanical alloying; after uniform mixing, a graphite mold is filled with the mixture for prepressing, the prepressing pressure is 10-50 MPa, and prepressing is conducted for 10-30 s; and then hot pressed sintering is carried out, the sintering pressure is 20-50 MPa, the sintering temperature is 1400-2000 DEG C, heat preservation is carried out for 10-90 min, and the high-entropy alloy bonding phase SiC hard alloy composite material is prepared. The liquid phase generated in the high-entropy alloy sintering process is used for reducing the sintering temperature, the organization structure is improved, and the hardness and toughness of the tungsten carbide hard alloy are improved.

The present invention belongs to the technical field of liners, and specifically discloses a high-wear-resistant mixed pelletizing machine liner and a preparation method thereof. The liner includes a base layer and a wear-resistant layer composited on the surface of the base layer. The base layer is made of high-strength alloy steel material, and its chemical composition is calculated by mass percentage as follows: C: 0.25-0.35%, Si: 0.4-0.8%, Mn: 1.2-1.6%, Cr: 0.8-1.2%, Mo: 0.2-0.4%, Ni: 0.3-0.6%, Nb: 1.0-1.6%, and the balance is Fe; the wear-resistant layer includes tungsten carbide particles, a composite alloy material, and an adhesive. The present invention adopts the above-mentioned high-wear-resistant mixed pelletizing machine liner and a preparation method thereof, aiming to solve the problems of insufficient wear resistance and short service life of existing mixed pelletizing machine liners, and improve the comprehensive performance of the mixed pelletizing machine liner through composite structure design and special preparation process.

The invention relates to the technical field of material science, in particular to a high-strength hard alloy and a preparation method and application thereof.The preparation method comprises the following steps that S1, raw materials of tungsten carbide, cobalt, tantalum carbide, niobium carbide, titanium carbide, yttrium oxide, nickel and trace strengthening elements are weighed according to the preset weight, and a mixture A is formed; s2, placing the mixture A in wet ball-milling equipment for ball-milling treatment; s3, the slurry obtained after ball milling is subjected to drying treatment; s4, carrying out plasma activation treatment on the dried powder; s5, pressing the activated powder to form a compact green body; s6, the green body is subjected to second-stage sintering treatment in a vacuum sintering furnace; s7, after sintering is completed, cooling treatment is conducted; by optimizing the alloy formula and innovating the preparation process, the hardness, toughness and high-temperature resistance of the high-strength hard alloy are improved, meanwhile, the production process is simplified, and the overall performance and application universality of the material are improved.

The invention discloses a preparation method of a nickel-based tungsten carbide laser cladding wear-resistant gradient coating, which comprises the following steps: step 1, preparing mixed powder of a transition layer, a functional layer and a repair layer; step 2, pretreating a matrix: removing oxide skin on the surface of the matrix, polishing to be smooth, and preheating the matrix to 350-500 DEG C; step 3, sequentially preparing a first functional layer, a transition layer, a second functional layer and a repair layer by adopting a laser cladding process; and 4, coating post-treatment is conducted, specifically, the surface of the repairing layer is polished to the specified thickness, and the defect-free wear-resistant gradient coating is formed. Through gradient component layered design, the functional layer adopts high tungsten carbide content to maximize wear resistance, and the transition layer relieves thermal expansion difference between the coating and a matrix, reduces interface stress and reduces crack initiation; according to the repairing layer, micro-cracks and air holes generated in the cladding process are filled through low-hardness nickel-based components, and the compactness and surface integrity of the coating are remarkably improved.

The invention provides a high-performance nitrogen-containing hard alloy material based on a vanadium-titanium rare earth carbonitride solid solution and a preparation method of the high-performance nitrogen-containing hard alloy material, and belongs to the technical field of hard alloy cutting tool materials. Tungsten carbide of a hard phase is modified, meanwhile, the vanadium-titanium rare earth carbonitride solid solution and the boron quantum dot are introduced to modify the high-entropy alloy, through interaction of modified components, the hardness and transverse breaking strength of the hard alloy material are effectively improved, and meanwhile the phase granularity is reduced.

The invention provides an aerogel-based heat-preservation, heat-insulation and waterproof composite coating material for a building outer wall and a preparation method thereof, and belongs to the field of building materials. Through hydrophobic modified silicon dioxide aerogel, a lightweight heat insulation frame is provided, and the waterproofness and compatibility are improved; the mechanical property and the crack resistance are enhanced through the modified potassium titanate nanofibers, and self-adaptive heat insulation is achieved; the thermoelectric effect, the wear resistance and the thermal regulation performance are optimized through plasma treatment and polyaniline coated tungsten carbide nanoparticles; the heat management performance, the crack resistance and the comprehensive heat insulation and waterproof capacity are improved through graphene oxide composite modified boron nitride; the flexibility, the hydrophobicity and the interfacial compatibility are improved through organic silicon modified bisphenol A epoxy resin; and the performance of the coating is optimized through the synergistic effect of the components.

The invention discloses a laser cladding preparation method for improving the wear resistance of a cladding layer by doping tungsten carbide. According to the method, cladding process parameters are preliminarily obtained based on finite element heat flow analogue simulation, cladding layer preparation is carried out, cladding quality characterization is carried out to obtain the optimal cladding process parameters, and finally the cladding layer with the wear-resistant characteristic is obtained. The method comprises the following steps: firstly, constructing a heat flow coupling three-dimensional model, carrying out grid division, establishing a heat source model, defining thermophysical parameters of tungsten carbide (10-15%) nickel alloy composite powder and a matrix, and determining simulated boundary conditions; setting a multi-factor process parameter combination to carry out numerical simulation calculation, and determining laser processing process parameters of laser power, scanning speed and light spot diameter; preparing a cladding layer on the surface of the nodular cast iron by using tungsten carbide (10-15%) nickel alloy composite powder through a laser cladding method; and carrying out microscopic morphology and microhardness experiments to carry out quality analysis verification on the cladding layer, determining the optimal process parameters of laser power, scanning speed and light spot diameter when the cladding layer has no obvious defect morphology and the hardness is higher than that of the raw material, and obtaining the laser cladding preparation method for improving the wear resistance of the cladding layer by doping tungsten carbide. The invention provides a new research method and a high-quality preparation approach for improving the wear resistance of the cladding layer by tungsten carbide, and can be widely applied to the fields of strengthening and repairing mining machinery, aerospace parts and the like.

The invention discloses a vibrating screen type crushing tungsten carbide powder ball mill, and relates to the related field of tungsten carbide powder processing, the vibrating screen type crushing tungsten carbide powder ball mill comprises a support frame, ball milling cylinder bodies and a crushing box, the left and right positions of the inner side of the support frame are rotatably provided with the ball milling cylinder bodies through rotating shaft connecting sleeves, and the crushing box is fixed to the top surface position of the left end of the support frame; the inner side of the rotating gear is fixed on the outer side of the ball milling barrel body; a water outlet of the water tank is connected to the bottom end of the water conveying pipe, and the pressure nozzle is arranged on the outer side of the crushing roller. According to the ball mill for the tungsten carbide powder capable of being crushed in the vibrating screen mode, the water conveying mechanism is arranged, water storage treatment can be continuously carried out on rod pieces of the crushing rollers through the arrangement of the water conveying mechanism, and water spraying dust suppression treatment is carried out on crushed materials through matched arrangement of a pressure nozzle; and in addition, unqualified materials are subjected to secondary crushing treatment through vibrating screen type filtering, so that the working efficiency of the ball milling barrel body can be improved.

The invention relates to the technical field of alloy materials, and discloses a preparation method of a nano WC-Co hard alloy for micro drilling, the nano WC-Co hard alloy comprises the following raw materials by weight: 83-92 wt% of nano tungsten carbide, 7-17 wt% of ultrafine cobalt oxide powder, 0-1.5 wt% of a hard alloy grain growth inhibitor, and 0.2-3 wt% of a forming agent; the method comprises the following steps: 1, mixing nano tungsten carbide, superfine cobalt oxide powder, vanadium carbide and a forming agent, and adjusting a carbon balance point in the powder to be mixed by using free carbon black; 2, sequentially putting the powder and a forming agent into a ball mill, and mixing the materials by taking absolute ethyl alcohol as a ball milling medium; the superfine cobalt oxide powder is used for replacing superfine cobalt powder, so that the extension area of cobalt element powder is increased, the problem that the cobalt powder is extended into a sheet shape is avoided, the cobalt pool phenomenon is effectively reduced, meanwhile, crystal grain growth inhibition carbides are increased, the phenomenon that a binding phase in hard alloy is not uniform is avoided, the service life of the finished micro-small-diameter drill bit special for the PCB is guaranteed, and the service life of the finished micro-small-diameter drill bit special for the PCB is prolonged. And the product quality is further improved.

The invention provides a surface cubic-phase-rich functional modified hard alloy and a preparation method, and belongs to the technical field of hard alloy cutter materials. According to the method, tungsten carbide is subjected to yttrium doping treatment, boron-containing titanium carbide and cobalt-molybdenum composite powder are used together, a nitriding sintering process is combined, diffusion and permeation of nitrogen atoms are promoted, the microstructure of the alloy is regulated and controlled, enrichment of a cubic phase on the surface of the alloy is achieved, and the surface-rich cubic phase functional modified hard alloy is obtained; the Vickers hardness and the heat conductivity coefficient of the hard alloy material are effectively improved, and meanwhile the friction coefficient of the material is reduced; the surface layer rich cubic phase of the modified hard alloy material is provided with the functional gradient layer, the binding force of a coating of a tool material prepared from the modified hard alloy material and a matrix can be improved, and therefore the service life of the tool material is prolonged.

The invention belongs to the technical field of powder metallurgy production, and discloses a silver tungsten carbide graphite waste recovery treatment device and method.The silver tungsten carbide graphite waste recovery treatment device comprises a treatment box, a conveying module is arranged on the outer wall of the treatment box, a discharging port is formed in the outer wall of the treatment box, and smashing rollers are arranged on the inner wall of the treatment box; a downward pressing mechanism is arranged on the inner wall of the treatment box, a shielding mechanism is arranged on the outer wall of the treatment box, and a screening mechanism is arranged on the outer wall of the treatment box; the screening mechanism comprises a motor, an output shaft of the motor is fixedly connected with a chain wheel A, and the outer wall of the chain wheel A is in transmission connection with a chain wheel B through a chain; through cooperation of the motor and the trapezoidal block, waste materials crushed by the crushing roller can fall on the screen, and the waste materials can be stacked more uniformly through continuous movement of the moving frame and the screen, so that the problem that the screening efficiency is affected due to the fact that the waste materials fall on the screen and then are stacked at one position is avoided.

The invention discloses a rare earth modified tungsten carbide alloy and a preparation method thereof, and belongs to the technical field of tungsten carbide alloys. The rare earth modified tungsten carbide alloy comprises 80 wt.%-90 wt.% of a hard phase and 10 wt.%-20 wt.% of a matrix, and the hard phase is uniformly distributed in the matrix; the hard phase comprises a rare earth modified tungsten carbide inner core, the rare earth modified tungsten carbide inner core is coated with a nano tungsten carbide shell, the rare earth modified tungsten carbide inner core accounts for 85-95 wt.% of the mass of the hard phase, and the nano tungsten carbide shell accounts for 5-15 wt.% of the mass of the hard phase. By the adoption of the rare earth modified tungsten carbide alloy and the preparation method thereof, the problem that an existing tungsten carbide alloy is poor in hardness and abrasion resistance can be solved, and the toughness of the tungsten carbide alloy can be improved.

The invention discloses a high-performance special ceramic material and a preparation process thereof, and the preparation process comprises the following steps: proportioning tungsten carbide, ternary boride, titanium nitride, molybdenum, nickel, silicon, cobalt and other raw materials with nano silicon carbide whiskers according to a ratio, carrying out ball milling treatment, adding a forming agent, and continuing ball milling and granulation; and then, carrying out compression molding on the ceramic powder, carrying out liquid phase sintering in a CO atmosphere, and cooling to room temperature to obtain the high-performance special ceramic material. The Mo3NiB3 ternary boride is introduced, so that the hardness and impact resistance of the ceramic material can be improved, the interface bonding force between a ceramic matrix and a reinforcing phase is enhanced, and the bending strength is improved; the nano silicon carbide whiskers are subjected to nickel plating treatment, so that the interface bonding force can be improved, microcracks are reduced, and the strength and toughness of the ceramic material are enhanced; by optimizing the sintering process and adopting a staged heating mode, grain growth can be controlled, and the density and mechanical properties of the ceramic material are effectively improved.

The invention relates to the technical field of cables, and provides a corrosion-resistant overhead cable which sequentially comprises a conductor, an insulating layer, a shielding layer, a lining layer and an outer sheath layer from inside to outside. The outer sheath layer comprises the following raw materials in parts by weight: 60-70 parts of polyethylene, 20-30 parts of an ethylene-vinyl acetate copolymer, 10-15 parts of polyphenylene sulfide, 25-35 parts of a flame retardant, 0.5-1 part of an antioxidant, 2-3 parts of a lubricant, 3-5 parts of a compatilizer and 15-25 parts of a rectorite / tungsten carbide composite material; the mass ratio of rectorite to tungsten carbide is (1: 9)-(9: 1). According to the technical scheme, the problem of poor corrosion resistance of the overhead cable in the prior art is solved.

The invention discloses a rare earth oxide modified high-entropy hard alloy and a preparation method thereof. A high-entropy hard phase (high-temperature calcination), a high-entropy binding phase and rare earth oxide are adopted, grinding, pressing and air pressure sintering at the temperature of 1450-1550 DEG C are conducted, and the high-entropy hard phase is prepared from tungsten carbide, titanium carbide, zirconium carbide, yttrium carbide, manganese carbide, chromium carbide and molybdenum carbide; the high-entropy binding phase comprises the following components: cobalt and a CoCrFeNi-series high-entropy alloy; and the component of the rare earth oxide is Y2O3 or Nd2O3. The prepared rare earth oxide modified high-entropy hard alloy has the advantages of high strength, high compactness, high hardness, high wear resistance and the like.

The invention provides a sleeve material for molding an aspheric glass lens and a preparation method of the sleeve material. The method comprises the steps that 1, raw material powder is mixed and dried, tungsten carbide powder and Si3N4 powder are mixed in a ball milling tank in an inert atmosphere to obtain composite powder, and the adding amount of the Si3N4 powder is 1 wt%-15 wt%; (2) die filling; putting the composite powder into a graphite female die, and pre-pressing under the pressure of 5-20 MPa; (3) sintering is conducted, specifically, the mold is placed in an SPS system, the initial axial pressure ranges from 5 MPa to 10 MPa, vacuumizing is conducted till the pressure is 10 Pa or below, gradient heating sintering is conducted, the highest sintering temperature ranges from 1500 DEG C to 1900 DEG C, the highest sintering pressure ranges from 40 MPa to 60 MPa, and after heat preservation is finished, the mold is taken out after cooling; and (4) sampling: carrying out sand blasting treatment on the graphite on the surface of the sample to obtain the sleeve material for molding the aspheric glass lens. The material has a lower thermal expansion coefficient.

The invention discloses a high-hardness tungsten carbide-cobalt hard alloy and a preparation method thereof. A production raw material formula comprises the following components in parts by mass: 100 parts of tungsten carbide powder, 6-20 parts of cobalt powder, 0.2-1.3 parts of a composite sintering aid, 0.5-4 parts of a wet grinding medium and 0.2-4 parts of a forming agent, the composite sintering aid is composed of rare earth oxide and cobalt phosphide according to the mass ratio of (1-5): 1. The method has the advantages that on the premise that the toughness of the tungsten carbide-cobalt hard alloy is slightly improved, the hardness and wear resistance of the alloy are remarkably improved, and the industrial problems that the hardness improvement of the tungsten carbide-cobalt hard alloy with a single sintering aid is limited and the toughness of the alloy is lost are solved.

The invention discloses beryllium copper plate calendaring forming equipment, and relates to the technical field of beryllium copper plate manufacturing, and the beryllium copper plate calendaring forming equipment comprises a rack, a transmission assembly, a cleaning assembly and a driving guide assembly. A multi-layer composite calendering roller structure is adopted, an outer tungsten carbide wear-resisting layer is matched with a middle copper-aluminum alloy heat conduction layer and a 42CrMo alloy steel support layer, a dynamic temperature control system is formed under the synergistic effect of a spiral heating channel, a spiral cooling channel, a microwave heating tank and a liquid nitrogen cooling tank, the forming precision and the material performance are remarkably improved, and the service life of the calendering roller is prolonged. A transmission assembly, an automatic cleaning assembly on the inner wall of the rack and driving guide assemblies at the two ends are externally arranged, the rolling stability is guaranteed, the position of the beryllium copper plate can be adjusted in real time, the intelligent control platform integrates the multispectral monitoring and touch control adjusting functions, closed-loop optimization of thermal parameters is achieved through a temperature control unit, and the working efficiency is improved. And therefore, the equipment has high-efficiency forming, intelligent monitoring and process self-adaptive capabilities in the machining process.

The invention relates to the technical field of stainless steel pneumatic cylinder barrels, and particularly discloses a wear-resistant stainless steel pipe for a pneumatic cylinder barrel and a preparation process thereof.The wear-resistant stainless steel pipe for the pneumatic cylinder barrel comprises the steps that firstly, a powder metallurgy method is adopted, tungsten carbide, cerium oxide, chromium nitride and other components are added into stainless steel powder, and the performance of a steel pipe base body is enhanced; the corrosion-resistant alloy layer is deposited on the surface of the steel pipe, so that the corrosion resistance, wear resistance and other properties of the steel pipe are enhanced, finally, a silicon nitride wear-resistant ceramic layer is sintered on the surface of the corrosion-resistant coating, and two lubricants of graphite and molybdenum sulfide are synthesized in gaps and holes of the wear-resistant ceramic layer. The defects on the ceramic surface are blocked; and the ceramic coating is endowed with a self-lubricating function.

The invention relates to the technical field of cutting tool materials, and discloses a hard alloy applied to a cutting tool and a preparation method thereof.The hard alloy is prepared from, by weight, 70-80 parts of tungsten carbide powder, 5-10 parts of cobalt powder, 2-6 parts of copper powder, 1-5 parts of silver powder, 0.2-0.5 part of tantalum carbide powder, 0.2-0.5 part of titanium carbide powder and 0.1-0.3 part of nickel powder, and the particle size of all the components is smaller than 10 micrometers. The copper powder and the silver powder are added into the raw materials, half of the silver powder is ground to be finer in particle size in the production process, the silver powder is evenly mixed with other powder, the mixture is pressed into a blank through a mold, and after sintering is conducted, copper and silver elements can be evenly distributed on the inner layer and the outer layer of the hard alloy; by means of the excellent heat conduction effect of copper and silver, heat generated when the cutting tool made of the hard alloy is used can be well carried away by cutting fluid, abrasion of the tool is reduced, and the service life of the tool is prolonged.

The invention relates to the technical field of flux-cored wires. The preparation method comprises the following steps: weighing the following raw materials in parts by weight: 4-6 parts of chromium carbide powder, 7-9 parts of molybdenum powder, 6-8 parts of nickel powder, 10-15 parts of niobium powder, 15-18 parts of tungsten carbide powder, 7-11 parts of a modified titanium carbide agent, 5-8 parts of a blending agent added based on boron and 2-4 parts of 30-mesh natural graphite; 1-2 parts of sodium fluosilicate; 1-2 parts of aluminum powder; and 70-75 parts of iron powder. The flux-cored wire can adapt to complex service environments of parts such as rollers and continuous casting crystallizers in the metallurgical industry, the service life of the parts subjected to surfacing repair is prolonged, the production efficiency of the parts subjected to surfacing repair is improved, the obtained flux-cored wire achieves balance of high-temperature performance, mechanical performance and low-temperature stability, and the comprehensive applicability of products is improved.

The invention relates to the field of hard alloy, and provides hard alloy, a preparation method thereof and application of the hard alloy in a hard alloy cutter. The hard alloy comprises the following components in every 100 parts by mass: 8-15 parts of a binder; the conditioning agent is prepared from vanadium carbide, ruthenium and tantalum carbide according to the mass ratio of (1 to 6) to (5 to 8) to 10; and the balance of tungsten carbide. The preparation method comprises the following steps: ball milling, drying and granulating, compression molding and hydrogen sintering. The hard alloy with excellent strength and toughness is obtained by optimizing the components and limiting the dosage of each component, and the service life is long when the hard alloy is applied to a blade.

The invention relates to the field of cutter coatings, and provides a coated hard alloy cutter aiming at the problem that the mechanical property of the cutter is influenced by poor binding force between the coating and a substrate, the cutter substrate is tungsten carbide-based hard alloy, and the hard alloy contains VC, Ru and TaC; and the coating sequentially comprises a molybdenum sulfide layer, an aluminum nitride layer and an aluminum titanium silicon nitride layer from inside to outside. By limiting the components of the cutter base body and the sequence and components of the multi-element coating, the cutter with good binding force between the coating and the base body and long service life is obtained.

The invention relates to the technical field of powder metallurgy, and particularly discloses an ultra-coarse grain WC-Co hard alloy and a preparation method thereof.The preparation method comprises the following steps that S1, the following raw materials including, by weight, 4.6-9.2 parts of cobalt powder, 96-102 parts of coarse grain tungsten carbide powder, 3.6-5.2 parts of functional gel, 3.4-4.6 parts of modified penetration enhancer, 2.2-2.8 parts of binder and 36-62 parts of organic solvent are prepared; step S2, preparation of a mixture; step S3, carrying out granulation treatment; step S4, compacting; step S5, pressurizing and sintering; the functional gel and the modified penetration enhancer are added, the functional gel contains yttrium oxide, polytannic acid, ultrafine tungsten carbide, tantalum carbide, chromium carbide, silica gel and other components, and the functional gel not only has excellent physical properties, but also can be cross-linked with the modified penetration enhancer to form a more compact silicon dioxide network structure; and the hardness, toughness, impact resistance and wear resistance of the alloy are improved.

The invention relates to a milling burr (1) for an electrically or pneumatically operated hand-held tool for deburring, shaping, grinding and finishing iron-free surfaces, comprising: - a shank portion (2) and - a milling portion (4) made of a hard metal, in particular tungsten carbide, which adjoins the shank portion (2) and ends in a milling tip (6), wherein the milling portion (4) has a milling length (f) and a plurality of cutting edges (10) which are separated by mutually spaced main flutes (14) which have a main flute depth (h) and extend helically in a first twist direction (16) with a first twist angle (α) along the milling length (f), wherein each of the cutting edges (10) has a rake face (20) and a relief face (24) and a cutting edge (12) at the transition of rake face (20) and relief face (24), forming a rake angle (γ) and a relief angle (δ). The milling burr (1) according to the invention is characterized in that said relief face (24) is a first relief face (24) and said relief angle (δ) is a first relief angle (δ), wherein the first relief face (24) is adjoined in the circumferential direction of the milling portion (4) by a second relief face (26) which extends at a second relief angle (ε), and, in the region of the milling portion (4) with the largest diameter, the first relief angle (δ) is in the range from 6° to 20° and the second relief angle (ε) is in the range from 8° to 30°, and the second relief angle (ε) is greater than the first relief angle (δ). The invention also relates to the use of such a milling burr (1).

The invention relates to the technical field of electrode paste, in particular to a preparation method of high-pressure-resistant high-strength graphite enhanced electrode paste, which comprises the following steps: sequentially performing oxidation modification and silane modification on crystalline flake graphite powder, preparing silane modified graphite powder, and synchronously preparing a boron-nitrogen source precursor; coating the aminated carbon quantum dots with silicon to obtain silicon-coated carbon quantum dots; preparing a composite adhesive, a tungsten carbide-aluminum nitride composite reinforced phase and carbon-plated silicon powder; the preparation method comprises the following steps: blending and kneading silane modified graphite powder, a boron-nitrogen source precursor and other components, and pressing under gradient pressure to obtain a green body; and performing segmented roasting on the green body, and cooling to obtain the target electrode paste. According to the invention, crystalline flake graphite oxidation-silane modification is adopted to optimize interfacial compatibility, silicon-coated carbon quantum dots are adopted to reinforce a bonding system, a composite reinforcement phase is adopted to construct a mechanical support network, boron-nitrogen source in-situ doping supplemental reinforcement is adopted, and gradient pressure pressing and segmented roasting are combined to ensure that the structure is compact. The normal-temperature compressive strength, high-temperature mechanical stability and compactness of the electrode paste are improved through the synergistic effect of all links, and the electrode paste can stably adapt to the high-temperature and high-load working conditions.

The invention relates to the technical field of wear-resistant materials, in particular to a nano wear-resistant composite material and a preparation method and application thereof, and the nano wear-resistant composite material comprises the following raw materials in parts by weight: 45-50 parts of nano tungsten carbide, 10-15 parts of cobalt powder, 7-11 parts of a modified nano titanium nitride agent, 5-7 parts of nano neodymium oxide, and 4-6 parts of a nano TaC-doped complexing agent. According to the nano wear-resistant composite material, the nano tungsten carbide is matched with the cobalt powder and the nano neodymium oxide, the modified nano titanium nitride agent, the doped nano TaC and the synergist are coordinated and matched, and the raw materials are coordinated and synergistic, so that the wear resistance, the yield strength performance and the fatigue resistance of the obtained nano wear-resistant composite material are coordinated and improved; meanwhile, the product is excellent in performance stability under different degrees of salt corrosion conditions.

The invention discloses a high-wear-resistance tungsten carbide alloy and a preparation method thereof, and belongs to the technical field of tungsten carbide alloys. According to the high-wear-resistance tungsten carbide alloy, spherical hard particles are evenly distributed in a matrix, the mass percent of the hard particles is 80 wt.%-90 wt.%, and the mass percent of the matrix is 10 wt.%-20 wt.%; the hard particles comprise the following components in percentage by mass: 75 to 80 weight percent of composite tungsten carbide particles, 5 to 10 weight percent of cobalt powder, 2 to 3 weight percent of titanium powder, 2 to 3 weight percent of zirconium powder, 0.5 to 1 weight percent of rare earth oxide and 5 to 10 weight percent of nano carbon black. By adopting the wear-resistant tungsten carbide alloy and the preparation method thereof, the problem that the wear resistance of the tungsten carbide alloy is affected due to the fact that the hardness and the toughness of the existing tungsten carbide alloy cannot be synergistically enhanced can be solved.