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CN-121992240-A - Nickel-based tungsten-doped high-temperature self-lubricating material and preparation method thereof

CN121992240ACN 121992240 ACN121992240 ACN 121992240ACN-121992240-A

Abstract

The invention discloses a nickel-based tungsten-doped high-temperature self-lubricating material and a preparation method thereof, wherein the method comprises the steps of firstly, pouring tungsten powder into electroplating solution after pretreatment of water, and carrying out ultrasonic mixing to prepare nickel-plated tungsten powder; the method comprises the steps of mixing nickel-plated tungsten powder, nickel powder, molybdenum powder, rare earth yttrium powder and calcium fluoride in proportion to obtain composite raw powder, pouring the composite raw powder into ethanol solution, mixing, stirring and drying to obtain composite powder, ball-milling the composite powder to obtain uniform composite powder, and performing plasma sintering on the composite powder to obtain the nickel-based tungsten-doped high-temperature self-lubricating material. The nickel-based tungsten-doped high-temperature self-lubricating material disclosed by the invention takes Ni-Mo alloy as a matrix, improves the high-temperature strength and hardness, wear resistance and self-lubricating performance by adding nickel-plated tungsten powder and rare earth Y, and is suitable for the fields of aerospace, high-speed delivery and the like by introducing CaF 2 as a composite lubricant to strengthen the self-lubricating effect and adopting spark plasma sintering in combination.

Inventors

  • YE MENGYUAN
  • ZHAO FEI
  • ZHANG HUAN
  • LIU YIN
  • YUAN FEI

Assignees

  • 西安汉唐分析检测有限公司

Dates

Publication Date
20260508
Application Date
20260224

Claims (7)

  1. 1. The preparation method of the nickel-based tungsten-doped high-temperature self-lubricating material is characterized by comprising the following steps of: firstly, preparing nickel-plated tungsten powder, namely pre-treating tungsten powder by using aqua regia, then pouring the tungsten powder into electroplating solution for ultrasonic mixing, washing by using deionized water, washing by using ethanol solution, and drying to obtain nickel-plated tungsten powder, wherein the electroplating solution takes nickel sulfate as main salt, sodium hypophosphite as a reducing agent, trisodium citrate and sodium pyrophosphate as buffering agents, boric acid as stabilizing agents, and sodium hydroxide is added to control pH; step two, batching, namely proportioning and weighing the nickel-tungsten powder obtained in the step one, nickel powder, molybdenum powder, rare earth yttrium powder and calcium fluoride to obtain composite raw powder; Pouring the composite raw powder obtained in the first step into a container filled with ethanol solution, placing the container on a mechanical stirrer for mixing and stirring to obtain composite powder slurry, and drying the composite powder slurry to obtain composite powder; Step four, final mixing, namely putting the composite powder obtained in the step three and the hard balls into a high-energy ball milling tank together, and putting the high-energy ball milling tank and a planetary ball mill for ball milling to obtain uniform composite powder; And fifthly, sintering, namely loading the composite powder obtained in the step four into a die for plasma sintering, and cooling along with the furnace temperature after the completion of the plasma sintering to obtain the nickel-based tungsten-doped high-temperature self-lubricating material.
  2. 2. The method for preparing the nickel-based tungsten-doped high-temperature self-lubricating material is characterized in that in the first step, the granularity of tungsten powder is 10-15 mu m, the concentration of nickel sulfate in an electroplating solution is 20-35 g/L, the concentration of sodium hypophosphite is 30-50 g/L, the concentration of trisodium citrate is 5-10 g/L, the concentration of sodium pyrophosphate is 30-60 g/L, the concentration of boric acid is 25-45 g/L, the pH is controlled to be 9-13 by adding sodium hydroxide, the ultrasonic mixing time is 10-30 min, the electroplating solution is washed 3-5 times by deionized water, the ethanol solution is washed 3-5 times, and the electroplating solution is placed into a drying box at 80-120 ℃ for drying.
  3. 3. The preparation method of the nickel-based tungsten-doped high-temperature self-lubricating material is characterized in that in the second step, the mass percentage of nickel powder is 50% -70%, the mass percentage of molybdenum powder is 20% -40%, the mass percentage of rare earth yttrium powder is 1% -3%, the mass percentage of calcium fluoride is 1% -5%, and the mass percentage of nickel-plated tungsten powder is 3% -15%.
  4. 4. The preparation method of the nickel-based tungsten-doped high-temperature self-lubricating material is characterized in that the rotating speed of mixing and stirring in the third step is 100-180 r/min, the time is 1-3 h, the temperature of drying treatment is 60-90 ℃, and the heat preservation time is 2-5 h.
  5. 5. The method for preparing the nickel-based tungsten-doped high-temperature self-lubricating material according to claim 1, wherein the ball-milling adopted in the fourth step is 1:1-6:1 in ball-material ratio, and the ball-milling time is 6-12 h.
  6. 6. The method for preparing the nickel-based tungsten-doped high-temperature self-lubricating material according to claim 1, wherein the temperature rising rate of plasma sintering in the fifth step is 5-15 ℃ per minute, the sintering temperature is 850-1000 ℃, and the sintering is carried out for 5-25 minutes under the pressure of 30-100 MPa.
  7. 7. A nickel-based tungsten-doped high-temperature self-lubricating material, which is characterized by being prepared by the method of any one of claims 1-6.

Description

Nickel-based tungsten-doped high-temperature self-lubricating material and preparation method thereof Technical Field The invention belongs to the technical field of preparation of lubricating materials, and particularly relates to a nickel-based tungsten-doped high-temperature self-lubricating material and a preparation method thereof. Background High temperature self-lubricating composites, particularly materials that maintain good frictional wear properties over a wider or higher temperature range, have become an important research direction. However, most of the current research is still in the laboratory stage and is difficult to apply on a large scale. In the fields of aerospace, high-speed delivery and the like (such as high-temperature heat-insulating engine bearings and nuclear power valves), materials which can keep stable lubrication and wear resistance at extremely high temperature and high speed are needed, so that the development of novel wide-temperature-range antifriction wear-resistant self-lubricating composite materials is significant. Under the working condition that the grease lubricant fails, the solid lubricant is adopted as an effective method. Based on this, there is a need to develop a Ni-based self-lubricating composite material excellent in combination properties. Disclosure of Invention The technical problem to be solved by the invention is to provide a preparation method of a nickel-based tungsten-doped high-temperature self-lubricating material aiming at the defects in the prior art. The nickel-based tungsten-doped high-temperature self-lubricating material takes Ni-Mo alloy as a matrix, improves the high-temperature strength, wear resistance and self-lubricating performance by adding nickel-plated tungsten powder and rare earth Y, introduces CaF 2 as a composite lubricant, enhances the self-lubricating effect, combines the discharge plasma sintering preparation process with the characteristics of quick heating, short sintering time, controllable tissue structure and the like, improves the compactness of the nickel-based tungsten-doped high-temperature self-lubricating material, and provides a high-performance high-temperature self-lubricating composite material. In order to solve the technical problems, the technical scheme adopted by the invention is that the preparation method of the nickel-based tungsten-doped high-temperature self-lubricating material is characterized by comprising the following steps: firstly, preparing nickel-plated tungsten powder, namely pre-treating tungsten powder by using aqua regia, then pouring the tungsten powder into electroplating solution for ultrasonic mixing, washing by using deionized water, washing by using ethanol solution, and drying to obtain nickel-plated tungsten powder, wherein the electroplating solution takes nickel sulfate as main salt, sodium hypophosphite as a reducing agent, trisodium citrate and sodium pyrophosphate as buffering agents, boric acid as stabilizing agents, and sodium hydroxide is added to control pH; step two, batching, namely proportioning and weighing the nickel-tungsten powder obtained in the step one, nickel powder, molybdenum powder, rare earth yttrium powder and calcium fluoride to obtain composite raw powder; Pouring the composite raw powder obtained in the first step into a container filled with ethanol solution, placing the container on a mechanical stirrer for mixing and stirring to obtain composite powder slurry, and drying the composite powder slurry to obtain composite powder; Step four, final mixing, namely putting the composite powder obtained in the step three and the hard balls into a high-energy ball milling tank together, and putting the high-energy ball milling tank and a planetary ball mill for ball milling to obtain uniform composite powder; And fifthly, sintering, namely loading the composite powder obtained in the step four into a die for plasma sintering, and cooling along with the furnace temperature after the completion of the plasma sintering to obtain the nickel-based tungsten-doped high-temperature self-lubricating material. The preparation method of the nickel-based tungsten-doped high-temperature self-lubricating material is characterized by comprising the steps of firstly controlling the granularity of tungsten powder to be 10-15 mu m, then washing the nickel powder in an electroplating solution for 3-5 times by deionized water for 3-5 times and washing the nickel powder in an ethanol solution for 3-5 times, and then drying the nickel powder in a drying box at 80-120 ℃ according to the concentration of nickel sulfate in the electroplating solution, wherein the concentration of nickel sulfate in the electroplating solution is 20-35 g/L, the concentration of sodium hypophosphite is 30-50 g/L, the concentration of trisodium citrate is 5-10 g/L, the concentration of sodium pyrophosphate is 30-60 g/L, and the concentration of boric acid is 25-45 g/L, and the pH=9-13 is controlled by a