40 results about "Sphericity" patented technology

The invention discloses a preparation method of high-toughness nickel-based alloy composite powder for additive manufacturing. The method comprises the steps that nickel-based alloy matrix powder and nanometer reinforced particles are fed into a forming cavity, under the inert atmosphere and cooling conditions, a spiral blade is driven to rotate at the high speed of 15000-30000 rpm, meanwhile, the pressure in the cavity is maintained to be 2-8 MPa, and treatment is conducted for 30-120 minutes; and through the synergistic effect of kinetic energy and high-speed airflow, combination of size selective milling and cold welding is achieved, and the core-shell structure composite powder with matrix powder evenly coated with nano-reinforced particles is prepared. According to the preparation method, ball-milling-medium-free design is adopted, powder pollution and sphericity deterioration are avoided, and the prepared composite powder has high sphericity and fluidity, is suitable for the laser additive manufacturing process and can effectively refine grains, inhibit element segregation, cooperatively improve the strength and toughness of components and solve the problem of high-plasticity inversion.

The invention relates to a powder sphericity detection method, relates to the technical field of powder property detection, and solves the problem of poor accuracy of an existing powder sphericity detection method. The detection method comprises the following steps: randomly extracting powder to be detected, and obtaining a contour descriptor of each powder particle; calculating a geometrical shape factor and a mesoscopic descriptor of each powder particle according to the contour descriptor of each powder particle; classifying the powder to be detected according to the section morphology of the powder particles, and counting the number of the powder particles in the powder with different section morphology types; according to the number of the powder particles in the powder of each section morphology type and the geometrical shape factor and the mesoscopic descriptor of each powder particle, calculating the average sphericity value of the powder of each section morphology type; and calculating the final sphericity degree of the powder to be measured based on the average sphericity degree value of the section morphology type powder. According to the invention, scientificity and accuracy of a powder sphericity detection result can be ensured.

The invention relates to the technical field of oil and gas drilling and production, and discloses a method for determining the sphericity of rock debris, computing equipment and a machine readable storage medium. The method for determining the sphericity of the rock debris comprises the following steps: acquiring an original image of a rock debris sample, and preprocessing the original image to obtain a target image; according to the target image, edge detection is carried out, rock debris adhesion particles are separated, the rock debris contour is determined, geometric parameter calculation is carried out according to the rock debris contour, target geometric parameters of the rock debris sample are determined, and the target geometric parameters comprise the actual area, the perimeter, the minimum circumcircle area, the equivalent ellipse long axis length and the equivalent ellipse short axis length; and determining the rock debris sphericity of the rock debris sample according to the target geometric parameter and the lithology type of the rock debris sample. Finally, high-precision, high-efficiency and low-cost rock debris sphericity measurement is realized.

The application discloses a kind of multi-dimensional evaluation and anchor point constraint scoring method of particle shape, belong to the technical field of particle shape analysis.The method includes: obtaining the three-dimensional grid model of particle sample and pre-processing;Extract the multi-dimensional shape features including corner angle, sphericity, size, symmetry, texture and taper;Filter key features by multi-model voting;Group key features according to preset dimension and carry out adaptive dimension reduction, construct multi-dimensional evaluation space;Determine anchor point sample set for each evaluation axis, construct two-classification sub-problems for the evaluation axis containing intermediate anchor point, determine initial scoring parameter using seven-model performance weighted integration;Based on the score relationship of low-end, intermediate and high-end anchor points, the initial parameter is corrected by ridge regression, and the final scoring parameter is obtained by sequential monotonicity check;Based on the final scoring parameter, the multi-dimensional score of the particle to be scored is carried out and the result is output.The application realizes the multi-dimensional automatic evaluation of particle shape, has the advantages of feature selection objectivity, weight distribution accuracy, intermediate morphological particle position rationality, dimension reduction method adaptivity, visualization richness and the like.

The application relates to the field of soft magnetic material preparation, and particularly discloses a centrifugal atomization method and system for preparing superfine soft magnetic powder. The method comprises the following steps: controlling the superheat degree of a Fe-Si-Al alloy melt, injecting the melt into a high-speed centrifugal atomizer through a laser texturing centrifugal disc to generate refined liquid drops; controlling the atmosphere and performing multi-stage cooling under a specific hydrogen proportion and a low-oxygen environment; preparing the powder through ultrasonic-assisted rapid cooling and solidification; adopting an intelligent algorithm and multi-stage separation to accurately classify the particle size; detecting the morphology, oxygen content and magnetic performance of the powder to screen qualified products; and finally realizing process optimization through equipment deviation analysis and system calibration. The method can accurately control the particle size distribution of the powder, effectively reduce the oxygen content, and significantly improve the sphericity and soft magnetic performance of the powder.

The invention relates to the field of soft magnetic material preparation, and particularly discloses a centrifugal atomization method and system for preparing superfine soft magnetic powder. The method comprises the steps that superheat degree control is conducted on Fe-Si-Al alloy melt, and refined liquid drops are generated through laser texturing centrifugal disc injection and high-speed centrifugal atomization; carrying out atmosphere control and multi-stage cooling in a specific hydrogen ratio and low-oxygen environment; preparing powder through ultrasonic-assisted quenching solidification; accurate particle size grading is carried out by adopting an intelligent algorithm and multi-stage separation; detecting morphology, oxygen content and magnetic performance of the powder to screen up-to-standard products; and finally, process optimization is realized through equipment deviation analysis and system calibration. The method can accurately control the particle size distribution of the powder, effectively reduce the oxygen content, and significantly improve the sphericity and soft magnetic performance of the powder.

The present invention discloses a bearing ball extrusion forming device and its process, belonging to the technical field of bearing ball production and processing. The bearing ball extrusion forming device includes a box body, a discharge chute, a stable material guiding component, a time-delay component and an extrusion forming component; the time-delay component includes a top plate, an upper time-delay plate and a lower time-delay plate; the top plate is fixedly installed on the top of the box body, the lower end of the top plate is fixedly connected with the upper time-delay plate, and the inner bottom of the box body is fixedly connected with the lower time-delay plate which is symmetrically arranged with the upper time-delay plate up and down. The lower end of the upper time-delay plate and the upper end of the lower time-delay plate are both located between the first spiral rolling mill and the second spiral rolling mill. By the above method, the present invention can avoid the problems of low ball forming rate and many burrs caused by the short contact time between the spiral rolling mill and the ball during extrusion, increase the forming time of the ball, make the shape of the ball closer to a spherical shape, improve the sphericity of the ball, and at the same time reduce the burrs of the ball. During secondary grinding, the grinding time is effectively reduced.

The application relates to a powder sphericity detection method and relates to the technical field of powder property detection, and solves the problem of poor accuracy of the existing powder sphericity detection method. The detection method comprises the following steps: randomly extracting a powder to be detected, and obtaining a contour descriptor of each powder particle; calculating a geometric shape factor and a mesoscopic descriptor of each powder particle according to the contour descriptor of each powder particle; classifying the powder to be detected according to the cross-section morphology of the powder particles, and counting the number of powder particles in different cross-section morphology types of powder; calculating the average sphericity value of each cross-section morphology type of powder according to the number of powder particles in each cross-section morphology type of powder and the geometric shape factor and the mesoscopic descriptor of each powder particle; and calculating the final sphericity of the powder to be detected based on the average sphericity value of the cross-section morphology type of powder. The application can guarantee the scientificity and accuracy of the powder sphericity detection result.

The invention discloses a method for mechanically shaping superfine powder, and relates to the preparation field of particle size control and morphology control of glass superfine powder, and the method comprises the following steps: 1, conveying a primarily crushed powder raw material into a multi-stage turbo-type shaping cavity which is composed of a fixed wall and a high-speed rotor, and the high-speed rotor is provided with a shaping medium; 2, synchronously applying an impact, shearing and rolling composite force field; 3, treating for 5-30 minutes in a low-temperature environment from-50 DEG C to normal temperature; 4, monitoring the sphericity degree and the particle size distribution of the powder in real time through an online particle image analyzer; 5, collecting the sphericity gt through a cyclone separator; and 0.95 of the superfine powder finished product is obtained. The sphericity gt of the powder is produced; 0.95, the surface roughness is Rat; the sphericity degree of the traditional ball milling process is generally 1t; and 0.75, microcracks generated by impact crushing are avoided through the synergistic effect of shearing and rolling.

A tantalum-tungsten alloy product and a preparation method therefor where the method comprises: (1) providing spherical tantalum-tungsten alloy powder, wherein the powder is characterized in that the lower limit of the particle size is 15 μm-25 μm, the upper limit of the particle size is 50 μm-60 μm, the time for 50 g of the powder to pass through a standard funnel is 5-10 seconds, the sphericity of the powder is greater than or equal to 0.8, the hollow particle ratio of the powder is less than or equal to 5%, and the apparent density is 9-11 g / cm3; (2) processing and molding the powder by using a 3D printing process to obtain a printed blank; (3) performing printing post-treatment on the blank; and (4) performing vacuum heat treatment on a product from step (3), wherein the temperature of the heat treatment is 1350° C. to 1750° C., and the time is 30-90 minutes.

The invention discloses a method and a device for preparing silicon nitride ceramic balls by a slope rolling titration method. According to the slope rolling titration balling device, a slope rolling method is creatively adopted, the influence of gravity on the sphericity degree of liquid drops is reduced, and silicon nitride green balls with ultrahigh roundness can be obtained; and the problems that a compact core part cannot be obtained due to low-density rolling forming of the silicon nitride powder, the ball is not round due to traditional direct titration, and the small balls cannot be produced in quantity and are provided with indentations due to compression forming are fundamentally solved.

The present application discloses a method and a statistical device for counting the number of inclusions, which are applied to counting manganese sulfide inclusions in free-cutting steel. The statistical method comprises: obtaining a first true number, a first area ratio, a first average area, a first average perimeter, a first average sphericity, and a first apparent number of manganese sulfide inclusions in multiple two-dimensional cross-sectional images of a training sample; constructing a statistical model based on the first true number, the first area ratio, the first average area, the first average perimeter, the first average sphericity, and the first apparent number; obtaining a second area ratio, a second average area, a second average perimeter, a second average sphericity, and a second apparent number of manganese sulfide inclusions in a metallographic image of a sample to be counted, and substituting these into the statistical model to obtain the number of manganese sulfide inclusions in the sample to be counted as output by the statistical model.

Provided is a bonding wire in which a coating layer having Au as a main component is provided on the surface of a core material having Ag as a main component, and which is capable of forming an FAB having a good shape and a high sphericity degree. This bonding wire (W) has a core material (10) containing Ag as a main component, and a coating layer (12) provided on the surface of the core material (10) and containing Au as a main component, the core material (10) containing one or more elements selected from Au, Pd, and In, and the ratio of the film thickness of the coating layer (12) to the diameter of the core material (10) is 0.0014-0.0048. The ratio of the intrinsic resistance of the core material (10) to the intrinsic resistance of the coating layer (12) is 85%-115%.

The invention relates to the technical field of spherical aluminum oxide quality detection, in particular to an intelligent detection method for spherical aluminum oxide quality, which comprises the following steps: collecting microscopic images and chemical component purity of a spherical aluminum oxide sample; outputting the sphericity degree and defect proportion of the spherical alumina sample; outputting a quality grade evaluation result; carrying out fluidity test on the spherical aluminum oxide sample, sequentially carrying out acquisition, comparison and auditing on image data of the spherical aluminum oxide sample, and calculating the flow velocity of the spherical aluminum oxide sample; determining a detection accuracy adjustment mode according to the velocity variance of the flow velocities of the plurality of spherical alumina samples, including adjusting the comparison type of the image data, or adjusting the auditing interval number of the image data; wherein the shooting frequency for collecting the image data is determined according to the instantaneous speed variation of the collision of the spherical aluminum oxide sample. According to the invention, the accuracy of alumina detection is improved.

The application relates to the field of amorphous alloy materials, in particular to a high-sphericity amorphous soft magnetic alloy powder and a preparation method thereof, the structural general formula of which is as follows: (Fe 0.65 Ni 0.1 Si 0.1 Mo 0.05 Cu 0.09 P 0.01 ) 100‑x (A a B 1‑a ) x , wherein A and B are the same or different and are selected from rare metals; when A and B are the same, a is 0; when A and B are different, a is 0.1-0.5; and x is 1-5; the amorphous soft magnetic alloy has a saturation magnetization intensity of greater than or equal to 172.7 A.m 2 / kg, a coercive force of only 28.4 A / m, can meet the application requirements of an iron loss Pc < 800 mW / cm m under the test conditions of 100 kHz and B 3 = 100 mT, and has excellent comprehensive soft magnetic performance with a magnetic permeability reduction of less than or equal to 30% under the condition of 100 Oe direct current superposition.

The utility model provides a standard ball rod for measuring error calibration of a phase type laser radar measuring system. The standard ball rod comprises two standard balls and a connecting rod, the two standard balls are fixedly connected to the two ends of the connecting rod; the length of the distance between the ball centers is 1-1.5 m, the diameter of the two standard balls is 100-150 mm, and the sphericity of the two standard balls is 2-5 microns. According to the standard ball rod for calibrating the measuring error of the phase type laser radar measuring system, the measuring error of the phase type laser radar measuring system can be accurately calibrated. According to the measurement method, a series of problems such as feeding the phase type laser radar into a laboratory or moving laboratory equipment into a plant are avoided, and the method has the characteristics of simplicity in operation, high universality, high measurement accuracy and reliability in work.

The invention belongs to the technical field of cambered surface measurement, and discloses a roundness measurement method and sphericity measurement method for a short arc-shaped surface, and the method comprises the following steps: dividing an arc-shaped surface into multiple layers, and determining the number of required measurement points according to a three-coordinate point collection principle; the positions of a plurality of points are uniformly collected at intervals on each layer, and an initial sphere model is established on a coordinate system according to the positions of the points which are actually measured and collected; second-time actual measurement is carried out, all actual measurement points are converted into a new coordinate system, and the normal distance and the total deviation between each actual measurement point and the center of the first sphere are calculated; through multiple times of measurement, optimal calculation is realized through error calculation and optimization until a set convergence condition is reached, and an actually measured radius R1 is obtained; and calculating a normal gap value, and taking the normal gap value as roundness. According to the method, the relationship between the normal error gap value and the radius error of the short arc during measurement is calculated, and the normal error gap value is used as the roundness and the sphericity, so that the measurement cost can be reduced, and the workpiece quality can be improved.

The invention discloses a simulation method based on a crystal plasticity finite element coupling irradiation effect and damage, and the method comprises the specific steps: S1, building a three-dimensional polycrystalline model with controllable grain size and sphericity based on electron back scattering diffraction (EBSD) experimental data; s2, constructing a crystal plastic model coupled with dislocation density evolution, distinguishing movable and immovable dislocation densities, and correcting a slip resistance formula; s3, introducing an irradiation-induced dislocation loop term into the crystal plastic model to add an irradiation effect in the slip resistance and dislocation evolution equation of the crystal plastic model, and coupling the maximum shear strain damage factor to a flow equation of the crystal plastic model; s4, a crystal plastic model is achieved through a UMAT subprogram, periodic boundary conditions are applied to the three-dimensional polycrystalline model to execute uniaxial stretching simulation, and a stress-strain curve is output through volume averaging on the basis of the crystal plastic model. The method can accurately predict the tensile properties of the nuclear power steel before and after irradiation, and has the advantages of clear physical significance, high calculation efficiency and the like.

The invention provides a sphericity error evaluation method based on a cone search algorithm. The method comprises the following steps: A, sampling to obtain coordinates of a collection point; calculating a least square ball center coordinate based on the acquisition point coordinate, and then calculating to obtain a least square ball error; b, constructing an auxiliary ball, determining coordinates of search points of the auxiliary ball, calculating the distance from each collection point to the search points, and solving a range value between the maximum distance and the minimum distance; searching point coordinates corresponding to the minimum value and the second minimum value in the range values are found; c, constructing a cone model, obtaining a cone search point, and calculating a quasi-sphere center coordinate; d, calculating a sphericity error f1 value and a sphere center coordinate of a '3 + 2 'structural form of a minimum containing area method based on the quasi sphere center coordinate; e, calculating a sphericity error f2 value and a sphere center coordinate in a '2 + 3' structural form based on a quasi sphere center coordinate calculation method; and F, comparing the f1 value with the f2 value, and outputting a minimum value of the f1 value and the f2 value as a sphericity error evaluation result. According to the method, the sphericity error evaluation efficiency and precision can be remarkably improved.

The invention provides a manufacturing method of an erosion-resistant nozzle, the nozzle is manufactured by using a hard alloy material through a laser powder bed melting process, and the specific technical scheme is as follows: WC-Co type spherical hard alloy powder is selected as a raw material, the content of Co in percentage by weight is 6%-20%, the fluidity of the powder exceeds 9.25 s / 50g, the apparent density is greater than 6.83 g / cm < 3 >, and the powder is prepared into a spherical hard alloy material; the spheroidization rate is greater than 99%, and the average sphericity of the powder is greater than 99%; in the printing process parameters, the thickness of a powder laying layer is 0.01-0.045 mm; the value range of the linear energy density of the laser is 0.3 J / mm to 0.8 J / mm; the scanning distance ranges from 0.01 mm to 0.15 mm; and the scanning path strategy is that the layers are alternately staggered by 67 degrees. The coal water slurry nozzle effectively solves the prominent problems that a traditional coal water slurry nozzle is serious in erosive wear, short in service life and the like. According to the additive manufacturing method, the advancement of the 3D printing technology and the excellent performance of the hard alloy powder are fused, so that a more efficient and economical nozzle manufacturing mode is provided, and the performance of the nozzle is remarkably improved.

The rare-earth-based magnet powder has an average value of 0.65 or more as sphericity P1 defined by an equation (1) of P1=Ls / Ll. In the equation (1), Ll is a length or a long side of a rectangle that circumscribes the rare-earth-based magnet powder in a photomicrograph so that an area of the rectangle is minimized, and Ls is a length of a short side of the rectangle that circumscribes the rare-earth-based magnet powder in the photomicrograph so that the area of the rectangle is minimized.

This invention belongs to the field of metallic materials technology, specifically a single-phase TiZrMo spherical refractory high-entropy alloy powder and its preparation method. The refractory high-entropy alloy powder is composed of any two of Al, Cr, and Nb, and Ti, Zr, and Mo. The atomic radius difference of the refractory high-entropy alloy powder is ≤6.5%, the alloy entropy enthalpy ratio Ω is ≥1.4, and the mixing enthalpy ΔH is... mix The energy density is -20.27 to -3.27 kJ / mol, and the vacancy electron concentration (VEC) is <4.96. Furthermore, the preparation method of this invention has the advantages of simple steps, easy composition control, high production efficiency, and near-net-shape forming. The prepared spherical single-phase BCC refractory high-entropy alloy powder has a high sphericity, smooth surface, and low cost. The high-entropy alloy bulk prepared from this powder has stable microstructure and properties, and its density (2.70–10.22 g / cm³) can be adjusted within a wide range. 3 It possesses both good plasticity (compressive fracture strain ≥10.0%) and strength (compressive strength ≥965MPa), making it suitable for large-scale industrial applications.

The present invention relates to a foamed bead having a foam structure, a method for producing such a bead, and a method for producing a molded component using the bead. The present invention relates to a foamed bead having a foam structure, the foamed bead having a spherical shape defined by a sphericity φ of more than 0.94 and less than 1.00, and having an angle of repose value of 31.0°-50.0° as measured in accordance with ISO 4324.

The application discloses a kind of cerium-rich R-T-B series sintered magnets and preparation method thereof, the preparation method includes the following steps: S1, preparation mixed powder, the mixed powder is obtained by the first R-T-B series alloy powder of cerium-rich rare earth and the second R-T-B series alloy powder of cerium-poor rare earth is mixed uniformly, wherein, the sphericity of the first R-T-B series alloy powder is not less than 0.75;S2, mixed powder is prepared into R-T-B series sintered magnet.The preparation method constructs the grain shell layer of low Ce content in the interior of cerium-rich R-T-B series sintered magnet, to improve the intrinsic coercivity of cerium-rich R-T-B series sintered magnet.By the preparation method of the application, high-performance R-T-B series sintered magnet rich in Ce element can be prepared, and the application of Ce resources in R-T-B series sintered magnet is promoted.

This invention provides a method for predicting the grouting intensity of marine reef limestone with poor pore structure. The method calculates the pore volume of the reef limestone as a percentage of the total reef limestone volume (the reef limestone rock porosity). It categorizes the equivalent diameter of interconnected pores in the reef limestone by size and calculates the volume ratio of each type of interconnected pore. It calculates the porosity of pore particles using the surface area and volume of the pore particles. Based on the porosity, the pore particles are classified, and the sphericity ratio of each type is calculated. The seepage coefficient is calculated based on the reef limestone porosity, the volume ratio of each type of interconnected pore, and the sphericity ratio of each type of pore particle. The flow rate of the grout under different pressures in the reef limestone is calculated using the seepage coefficient. Finally, the tensile strength of the reef limestone is calculated based on the flow rate before and after grouting. This precise permeability analysis reduces construction risks and costs while improving the bearing capacity of the foundation.

This disclosure provides a steel sheet with excellent hardenability and excellent cold workability. The steel sheet disclosed herein has the following composition by mass %: C: 0.15~0.50%, Si: 0.01~0.50%, Mn: 0.20~1.30%, P: less than 0.100%, S: less than 0.100%, Al: less than 0.100%, Cr: 0.01~1.20%, N: less than 0.0150%, and the balance being Fe and impurities. The total surface area of ​​ferrite and cementite particles is 95% or more, the average grain size of ferrite is 5.0~20.0 μm, and the Cr concentration in the cementite particles is [Cr]. θ and Mo concentration [Mo] θ To satisfy equation (1), the average particle size of the cementite particles is less than 1.50 μm, the sphericity of the cementite particles is greater than 85%, and the dispersion DI of the number of cementite particles in a small square partition with a side length of 10 μm, as defined by equation (2), is less than 45%. 2[Cr] θ +3[Mo] θ ≤3 / √C (1) DI=σ θ / N θ ×100 (2)

The invention relates to a verification method for testing and characterizing the equivalent diameter and sphericity of powder particles by an industrial CT (Computed Tomography) machine. The verification method comprises the steps that an industrial CT machine is adopted to scan a prefabricated standard verification piece, and the standard verification piece comprises a plurality of standard spheres which are mixed and stacked; constructing a digital three-dimensional image of the standard verification piece according to a scanning result of the industrial CT machine; scanning information of the standard sphere is obtained from the digital three-dimensional image through software, and the scanning information comprises the diameter and sphericity of the standard sphere; the scanning information is compared with nominal parameters of the standard sphere, and the nominal parameters comprise the nominal diameter and the nominal sphericity of the standard sphere; and based on the comparison result, judging whether the equivalent diameter and sphericity of the characterization powder particles tested by the industrial CT machine are accurate or not. According to the verification method, the composition condition of the standard sphere can be flexibly and conveniently simulated, so that whether the equivalent diameter and the sphericity degree of powder particles tested and represented by an industrial CT machine are accurate or not is accurately judged.

The invention relates to the technical field of chromium target material preparation, in particular to chromium powder and a preparation method thereof, a chromium target material, a chromium film and a base material. According to the chromium powder provided by the invention, particles are spherical, the purity is larger than or equal to 99.99%, the sphericity degree is larger than or equal to 0.8, the preparation requirement of a high-quality chromium target can be met, it is ensured that the sputtering stability of the chromium target can be ensured in the sputtering process, and the problem of film defects caused by impurities, air holes and uneven density is solved.

The application discloses a solid-liquid two-phase flow-based over-flow component wear analysis system and relates to the technical field of over-flow component wear analysis.The system comprises a sphericity generation module, a wear parameter generation module and a particle wear coefficient generation module; the shape of ore particles is collected and analyzed, the surface area ratio of the ore particles to a sphere with the same volume is taken as sphericity, the difference between the particle shape and a standard sphere is quantified, the influence of particles with different shapes on the wear of over-flow components is described in more detail, the number of ore particles in each sphericity interval in sample data is calculated, a particle wear coefficient is calculated in combination with a preset fixed coefficient, the actual wear potential of ore and slurry fluid to a centrifugal slurry pump is reflected through the particle wear coefficient, the wear potential of ore and slurry fluid to be conveyed by the centrifugal slurry pump is more accurately predicted, and the wear analysis of over-flow components is more accurate and reliable.

The invention relates to a low-hardness heat-conducting powder material for a copper-clad plate, which is characterized in that the powder material comprises the following components: 50-90% of zinc aluminate; the powder A is one or two of aluminum powder and magnesium powder, and the content of the powder A is 10-50%; the invention also discloses a preparation method of the low-hardness heat-conducting powder material for the copper-clad plate. According to the prepared low-hardness heat-conducting powder material for the copper-clad plate, the cumulative 50% particle size (D50) of the laser diffraction scattering particle size distribution measurement volume standard is 5-150 microns, the sphericity degree read by a microscopic particle imager is 0.95-1.00, the heat conductivity tested by a DRL-III heat conductivity coefficient tester is larger than 1.3 W / m.K, a drill bit of 0.3 mm is used for drilling a heat-conducting gasket, the abrasion condition is judged according to the weight loss of the drill bit, and the heat conductivity of the copper-clad plate is judged according to the weight loss of the drill bit. After 5000 holes are continuously drilled, the wear rate of the drill bit is less than 0.1%.