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CN-122008092-A - Composite abrasive grain superhard material segment type cutter head and manufacturing method thereof

CN122008092ACN 122008092 ACN122008092 ACN 122008092ACN-122008092-A

Abstract

The application relates to the field of tool manufacturing, and discloses a composite abrasive grain superhard material segment type tool bit and a manufacturing method thereof. The tool bit is based on an iron-nickel-cobalt-copper-tin bond and comprises diamond and cubic boron nitride composite abrasive particles. The core technical characteristics are that the surface layer is introduced with strong carbide forming elements and modified carbon-rich polymer precursors, a hard carbide phase which is dispersed and distributed is generated in situ in the hot pressing sintering process, and the inner layer contains hexagonal boron nitride self-lubricating phase and high-heat-conductivity spherical copper powder. The whole tool bit adopts a laminated structure, the mismatch of thermal expansion coefficients among materials is relieved through an interface gradient layer, and directional cooling is implemented in the manufacturing process, so that residual compressive stress is induced on the side surface of the tool bit. According to the application, by utilizing the linkage of the material components and the cooling process, the self-maintenance of the side high wear resistance and the end face U-shaped self-sharpening form is realized, the mechanical holding force of the matrix on abrasive particles is enhanced, and the defects of cutter head wear thinning and jamming in the processing process are effectively overcome.

Inventors

  • CHEN LIANGYU
  • CHEN TAO
  • QIN XIAOQIAN

Assignees

  • 山东友江智能装备有限公司

Dates

Publication Date
20260512
Application Date
20260407

Claims (10)

  1. 1. A composite abrasive grain superhard material segment type cutter head is characterized by being prepared by hot-pressing and sintering the following raw materials, by weight, 25% -45% of iron powder, 5% -15% of nickel powder, 5% -12% of cobalt powder, 20% -40% of copper powder and 2% -8% of tin powder, wherein the surface raw materials comprise 1.0% -5.0% of strong carbide forming element powder, 2.0% -8.0% of hard alloy powder and 0.5% -2.0% of modified carbon-rich polymer precursor, the inner raw materials comprise 0.5% -2.5% of hexagonal boron nitride and 5.0% -15.0% of spherical copper powder, the surface raw materials comprise composite abrasive grains, and the composite abrasive grains comprise 9% -60% of diamond and cubic boron nitride by volume.
  2. 2. The segment-type tool bit of composite abrasive grain superhard material of claim 1, wherein the strong carbide forming element powder is one or more of chromium powder, tungsten powder, titanium powder, vanadium powder and silicon powder, and the hard alloy powder has average grain size Tungsten carbide powder or titanium carbide powder of 1 μm to 5 μm.
  3. 3. The segment-type tool bit of the composite abrasive particle superhard material of claim 1, wherein the modified carbon-rich polymer precursor is prepared from the following raw materials, by weight, 100 parts of phenol, 80-90 parts of 37wt% formaldehyde solution, 0.5-1 part of oxalic acid and 5-10 parts of nano-crystalline flake graphite.
  4. 4. The segment-type cutter head of the composite abrasive grain superhard material of claim 1, wherein the surface layer raw material further comprises 1.0% -6.0% of micron-sized prealloy composite powder, and the micron-sized prealloy composite powder is prepared by high-energy ball milling of chromium powder, titanium powder and iron powder with the mass ratio of (2-3) being 1 (6-7).
  5. 5. The segment-type tool bit of the composite abrasive grain superhard material of claim 1, wherein the tool bit is of a laminated structure and comprises two surface lamination sheets, an inner lamination sheet and an interface gradient transition layer arranged between the two surface lamination sheets, and the volume concentration of the composite abrasive grains in the surface lamination sheets is 5% -15% higher than that of the inner lamination sheets.
  6. 6. A method of manufacturing a segment-type cutter head of composite abrasive grain superhard material according to any one of claims 1 to 5, comprising the steps of: (1) Respectively preparing surface lamination powder, inner lamination powder and interface gradient transition layer powder; (2) Symmetrically filling the powder into a die according to the sequence of the surface layer, the transition layer, the inner layer, the transition layer and the surface layer; (3) Carrying out hot-pressing sintering in a vacuum or argon environment, wherein the temperature is 820-1050 ℃, the unit pressure is 15-35 MPa, and the temperature is kept for 8-20 min; (4) And (3) performing directional cooling on the side surface of the die through a cooling device, and controlling the transverse temperature gradient to be 20-50 ℃/cm.
  7. 7. The method according to claim 6, wherein in the step (1), the modified carbon-rich polymer precursor is prepared by polycondensation of phenol and formaldehyde solution at 90-95 ℃ to a viscosity of 500-800 mPa.s, and adding nano-crystalline flake graphite for high-speed dispersion.
  8. 8. The method of claim 6, wherein in the step (1), the micron-sized prealloyed composite powder is prepared by ball milling chromium powder, titanium powder and iron powder for 12-24 hours under the protection of argon.
  9. 9. The method according to claim 6, wherein in the step (3), the temperature is raised to 600℃and kept for 5 minutes, and then the temperature is raised to the highest sintering temperature to sinter.
  10. 10. The method according to claim 6, wherein in the step (4), the self-sintering temperature is lowered to 500 ℃ at a rate of 20 ℃ to 40 ℃ per minute, and the cooling rate of the side surface is higher than that of the central portion by 10 ℃ to 25 ℃ per minute.

Description

Composite abrasive grain superhard material segment type cutter head and manufacturing method thereof Technical Field The invention relates to the technical field of tool manufacturing, in particular to a composite abrasive grain superhard material segment type tool bit and a manufacturing method thereof. Background Superhard tools for processing stone, reinforced concrete, ceramics and other materials are commonly used for cutting parts by adopting sintered segments. The traditional preparation process of the tool bit is to mix diamond or cubic boron nitride abrasive with metal bond powder and densify a matrix through a hot-press sintering process. The metal binder component of the tool bit prepared by the process tends to be uniformly distributed. However, in actual cutting or drilling operations, since the side surfaces are directly subjected to frictional loads of the material to be machined, lateral abrasion of the bit carcass is liable to occur, resulting in a continuous decrease in the bit thickness dimension with time. The loss of the thickness of the tool bit can directly change the width of the kerf, and the machining precision of the workpiece is affected. In the drilling process, the thinned tool bit is extremely easy to cause the problems of blocking of a drill core in a drill barrel or blocking of a drill bit in a building member and the like. Meanwhile, the accumulated friction heat in the cutting process easily causes the oxidation failure of the matrix metal, and the mechanical holding force of the matrix on the superhard abrasive is reduced. Such a reduction in holding force can lead to premature removal of the abrasive material before it is sufficiently worn, thereby limiting the overall machining efficiency and useful life of the tool. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a composite abrasive grain superhard material segment type cutter head and a manufacturing method thereof, which solve the problems that when the existing superhard material cutter head is used for cutting hard materials such as stone or concrete, the cutter head thickness is thinned due to insufficient wear resistance of side matrix metal, so that the machining precision is reduced, the cutter head is blocked, and the holding force of the matrix on the superhard abrasive is deteriorated along with the increase of cutting heat. In order to achieve the above purpose, the invention is realized by the following technical scheme: In a first aspect, the invention provides a segment-type cutter head of composite abrasive grain superhard material, which adopts the following technical scheme: A composite abrasive grain superhard material segment type cutter head is formed by hot-pressing and sintering the following raw materials, by weight, 25-45% of iron powder, 5-15% of nickel powder, 5-12% of cobalt powder, 20-40% of copper powder and 2-8% of tin powder, wherein the surface raw materials comprise 1.0-5.0% of strong carbide forming element powder, 2.0-8.0% of hard alloy powder and 0.5-2.0% of modified carbon-rich polymer precursor, the inner raw materials comprise 0.5-2.5% of hexagonal boron nitride and 5.0-15.0% of spherical copper powder, the cutter head comprises composite abrasive grains, and the composite abrasive grains consist of diamond and cubic boron nitride, and the volume concentration of the composite abrasive grains is 9-60%. By adopting the technical scheme, the strong carbide forming element powder and the modified carbon-rich polymer precursor in the surface layer raw material form a dispersed hard wear-resistant phase on the side surface layer through in-situ chemical reaction in the hot-press sintering process, and the hardness of the side surface of the cutter head is improved by the wear-resistant phase. The reaction and action mechanism are as follows: in the first stage, in the heating stage of hot-pressing sintering, the modified carbon-rich polymer precursor is pyrolyzed and cracked to release free carbon atoms and nano-scale crystalline flake graphite inside the matrix. In the second stage, activated carbon atoms diffuse to the surfaces of the strong carbide forming element particles in a high-temperature and high-pressure environment. As a result of the chemical reaction of the strong carbide-forming element with carbon, both undergo in-situ carbonization reactions at the contact interface, producing carbide particles of sizes between the nanometer and micrometer scale. And in the third stage, the generated carbide phase and the pre-added hard alloy powder form a multi-scale hardening framework, and the multi-scale hardening framework and the Fe-Ni-Co-Cu-Sn matrix are metallurgically bonded. The micro-nano composite reinforced structure improves the mechanical strength of the matrix, enhances the mechanical holding force of the matrix on diamond and cubic boron nitride by improving the wettability of an interface and forming chemical bonding, and del