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CN-121992344-A - High-pressure hot-pressing die antioxidation coating and preparation method thereof

CN121992344ACN 121992344 ACN121992344 ACN 121992344ACN-121992344-A

Abstract

The application relates to the technical field of alloy coating materials, and particularly discloses an antioxidant coating of a high-pressure hot-pressing die and a preparation method thereof. An antioxidation coating of a high-pressure hot-pressing die comprises a transition layer and a functional layer which are sequentially arranged outwards from a die substrate, wherein the transition layer is a TiN-SiC gradient composite layer, the functional layer takes Al 2 O 3 -NiCrAlY as a substrate, nano ZrB 2 and rare earth CeO 2 subjected to double modification treatment are compositely doped in the functional layer, and double-modified nano ZrB 2 is ZrB 2 particles coated with NiCr alloy through a silane coupling agent KH-560. The high-pressure hot-pressing die antioxidation coating disclosed by the application has both antioxidation and wear resistance, and effectively enhances the high-temperature hardness stability and wear resistance of the antioxidation coating.

Inventors

  • ZHOU SHAOJIAN
  • HE PINGZHAO
  • SHI LEI
  • ZHOU PENG
  • ZHANG GUOHUI

Assignees

  • 西安碳沣新材料科技有限公司

Dates

Publication Date
20260508
Application Date
20260409

Claims (10)

  1. 1. The high-pressure hot-pressing die oxidation-resistant coating is characterized by comprising a transition layer and a functional layer which are sequentially arranged outwards from a die substrate, wherein the transition layer is a TiN-SiC gradient composite layer, and the functional layer takes Al 2 O 3 -NiCrAlY as a substrate and is compositely doped with nano ZrB 2 subjected to double modification treatment and rare earth CeO 2 ; The functional layer is prepared from the following raw materials, by weight, of Al 2 O 3 -72 parts, niCrAlY18-24 parts, double-modified nano ZrB 2 -12 parts and CeO 2 0.8-2.2 parts, wherein the double-modified nano ZrB 2 is ZrB 2 particles coated with NiCr alloy by a silane coupling agent KH-560.
  2. 2. The high-pressure hot-pressing die oxidation-resistant coating according to claim 1, wherein the transition layer is linearly decreased from 80-85% to 30-35% by mass and the SiC is linearly increased from 15-20% to 65-70% by mass from the side close to the die substrate to the side close to the functional layer.
  3. 3. The high-pressure hot-pressing die oxidation-resistant coating according to claim 1, wherein the double-modified nano ZrB 2 is prepared by the following method: A1, dispersing nano ZrB 2 particles in absolute ethyl alcohol for ultrasonic treatment to obtain a suspension, then adding a silane coupling agent KH-560, regulating the pH of a system to 4.5-5.5, stirring and reacting for 2.5-3.5 hours under the conditions of 70-85 ℃ and the rotating speed of 300-500r/min, centrifuging and separating after the reaction is finished, and drying for 2-3 hours under the vacuum environment of 100-120 ℃ to obtain silane modified ZrB 2 ; And A2, dispersing silane modified ZrB 2 in NiCr salt solution, adding chromium citrate as a complexing agent, adjusting the pH to 8-9, adding hydrazine hydrate solution at 50-60 ℃, then carrying out heat preservation reaction for 1-2h, centrifuging and washing to be neutral after the reaction is finished, drying for 1-2h in a vacuum environment at 300-350 ℃, and grinding to obtain the double modified nano ZrB 2 .
  4. 4. The high-pressure hot-pressing die antioxidation coating according to claim 3, wherein in the step A1, the mass ratio of the nanometer ZrB 2 particles to the absolute ethyl alcohol is 1 (12-20), the ultrasonic power is 300-400W during ultrasonic treatment, and the ultrasonic time is 20-30min.
  5. 5. The high-pressure hot-pressing die antioxidation coating according to claim 4, wherein in the step A1, the addition amount of the silane coupling agent KH-560 is 2% -4% of the total mass of the suspension.
  6. 6. The high-pressure hot-pressing die antioxidation coating according to claim 5, wherein in the step A2, the mass ratio of the silane modified ZrB 2 to the NiCr salt solution is1 (20-30), the NiCr salt solution is prepared by nickel nitrate and chromium chloride, and the concentration of nickel ions in the NiCr salt solution is 0.08-0.12mol/L and the concentration of chromium ions in the NiCr salt solution is 0.03-0.05mol/L.
  7. 7. The high-pressure hot-pressing die antioxidation coating according to claim 6, wherein in the step A2, the mass concentration of the hydrazine hydrate solution is 20% -25%, and the addition amount of the hydrazine hydrate solution is 8% -12% of the total mass of the NiCr salt solution.
  8. 8. The method for preparing an oxidation resistant coating for a high pressure hot press mold according to any one of claims 1 to 7, comprising the steps of: S1, polishing a high-pressure hot-pressing die matrix until the surface roughness Ra is less than or equal to 0.2 mu m; s2, taking a Ti target and a SiC target as sputtering sources, sputtering and depositing a transition layer on a high-pressure hot-pressing die matrix, controlling the matrix temperature in the deposition process to be 320-420 ℃, and controlling the total deposition time to be 4-8 hours; S3, adopting a vacuum evaporation-radio frequency sputtering composite process, taking Al 2 O 3 and NiCrAlY targets as evaporation sources and sputtering sources respectively, mixing the double-modified nano ZrB 2 and CeO 2 into an Al 2 O 3 evaporation material in proportion, wherein the matrix temperature is 480-580 ℃, the evaporation power of Al 2 O 3 is 900-1300W, the sputtering power of NiCrAlY is 150-220W, the deposition rate is 0.25-0.55 mu m/h, and the total deposition time is 4-8h; And S4, after the deposition is completed, annealing the high-pressure hot-pressing die matrix at 680-720 ℃ for 1-3h, and cooling to room temperature along with a furnace to obtain the high-pressure hot-pressing die antioxidation coating.
  9. 9. The method for preparing an oxidation-resistant coating of a high-pressure hot-pressing die according to claim 8, wherein in the step S1, the polished high-pressure hot-pressing die substrate is placed in a chamber of a multi-target composite vacuum coating machine, and activation treatment is performed by adopting argon ion bombardment.
  10. 10. The method for preparing the high-pressure hot-pressing die antioxidation coating according to claim 9, wherein the specific process parameters of the argon ion bombardment activation treatment are that the argon flow is 22-28sccm, the bombardment voltage is 900-1300V, and the bombardment time is 18-32min.

Description

High-pressure hot-pressing die antioxidation coating and preparation method thereof Technical Field The application belongs to the technical field of alloy coating materials, and relates to an antioxidant coating of a high-pressure hot-pressing die and a preparation method thereof. The coating is widely applied to the industrial fields of powder metallurgy, advanced ceramic sintering, high-performance composite material molding and the like which need high-pressure hot-pressing technology, meets the surface protection requirements of various high-pressure hot-pressing molding dies, and can effectively solve the surface protection problem of the high-pressure hot-pressing dies when in service under the working condition of long-term high temperature and high pressure. Background The high-pressure hot press forming technology is used as a core process in the high-end manufacturing fields of aerospace, precision machinery, new energy and the like, and is widely applied to the preparation of key components such as special alloy, ceramic matrix composite materials, semiconductor packaging parts and the like by virtue of the advantages of realizing material densification forming and improving the precision and performance of workpieces under high-temperature and high-pressure environments. As a core bearing part of the technology, the high-pressure hot-pressing die needs to bear high temperature of 400-1200 ℃ and high pressure of 10-100MPa for a long time and periodically alternately impact cold and heat, and the surface of the high-pressure hot-pressing die is extremely easy to oxidize, corrode and wear, so that the service life of the die is shortened, the production cost is increased, the surface of a workpiece is possibly polluted due to falling of a surface oxide layer, and the quality stability of a product is affected. Therefore, the preparation of the high-performance antioxidant coating on the surface of the high-pressure hot-pressing die becomes a key means for improving the weather resistance of the die, prolonging the service period and guaranteeing the reliability of the forming process, and has important practical significance for promoting the technical upgrading and quality improvement and efficiency improvement of the high-end manufacturing field. At present, the component system and the preparation process of the prior high-pressure hot-pressing die antioxidation coating form a plurality of technical paths. In the aspects of components, the ceramic-based coating (such as Al 2O3、ZrO2、Cr2O3 and a composite system thereof), the metal ceramic coating (such as NiCrAlY, coCrAlY-based metal ceramic) and the silicide coating (such as MoSi 2、TiSi2 coating) are mainly included, the components can form a compact oxidation barrier layer on the surface of a die by virtue of excellent high-temperature chemical stability, high-temperature oxidation corrosion is resisted, and in the preparation process, the main stream technology comprises plasma spraying, physical Vapor Deposition (PVD), chemical Vapor Deposition (CVD), laser cladding and the like, wherein the plasma spraying is widely applied to the preparation of the coating of a large-scale high-pressure hot-pressing die due to high preparation efficiency and strong coating thickness controllability, and the PVD and CVD processes are suitable for the preparation of thin coatings on the surface of a precise small die, so that the combination precision of the coating and a matrix can be ensured. In the prior art, a plurality of related patents disclose the technical proposal of the die antioxidation coating, but all the prior art have certain defects, and are difficult to completely adapt to the severe service conditions of the high-pressure hot-pressing die. For example, patent application publication No. CN116789466A discloses a high-temperature resistant PVD coating for a die and a preparation method thereof, and the technical scheme is that a PVD process is adopted, a C/C composite material is taken as a base layer, a thick metal nitride transition layer and a carbon-containing thermosetting resin protective layer are arranged, a compact SiC ceramic coating is prepared through a SiC industrial synthesis furnace, and the oxidation resistance is improved by utilizing a SiO 2 layer formed at high temperature. However, the patent has the obvious defects that the carbon-containing component of the protective layer is easy to oxidize and degrade in a high-temperature environment of high-pressure hot pressing, so that the coating structure is loose, the high-temperature hardness is seriously attenuated, the wear resistance of the coating is not optimized pertinently, the high-pressure friction impact between a die and a workpiece is difficult to resist, and the suitability of the protective layer for the high-pressure hot pressing die is limited. Patent document CN113981397B discloses a gradient antioxidation coating of Cr 2O3/Al2O3 for titanium alloy and a prep