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CN-121976150-A - High-performance radial seal sheet material for rotor engine

CN121976150ACN 121976150 ACN121976150 ACN 121976150ACN-121976150-A

Abstract

The invention relates to the technical field of rotary engines, in particular to a radial sealing sheet material with high wear resistance and self lubrication. The invention prepares the radial sealing piece suitable for the high-power rotor engine by preparing the metal carbide coating by the Cr12MoV alloy tool steel through a diffusion method for the first time and matching with subsequent treatment. The invention not only improves the wear resistance and the service life of the sealing sheet, but also provides a technology for realizing noise reduction through the optimization of the material quality and the structure optimization of the sealing sheet for the first time. The method has simple and controllable process, and the obtained product has excellent performance and is convenient for industrialized application.

Inventors

  • CHEN ZHENG
  • GUO YONG

Assignees

  • 湖南大学

Dates

Publication Date
20260505
Application Date
20251211

Claims (10)

  1. 1. A high-performance radial sealing sheet material for a rotary engine is characterized by comprising a base material and a metal carbide coating, wherein the base material comprises Cr12MoV alloy tool steel, and the metal carbide coating is attached to the base material by a diffusion method and forms metallurgical bonding with the base material; The diffusion method comprises the steps of placing a Cr12MoV alloy tool steel radial sealing sheet subjected to mechanical polishing, degreasing and acid washing treatment in a composite molten salt composed of 40% -50% of sodium chloride, 40% -50% of potassium chloride, 2% -5% of sodium fluoride, 2% -5% of sodium carbonate and 1% -3% of functional oxide or functional salt, immersing the steel radial sealing sheet according to the proportion of 8% -12 kg of molten salt in each 1kg of workpiece, preheating the steel radial sealing sheet at 700 ℃ -750 ℃ for 20-40 min, then heating the steel radial sealing sheet to 900 ℃ -1100 ℃ at a heating rate of 3-5 ℃ per min, and preserving the temperature for 6-12 h to enable active elements to form a compact diffusion layer on the surface of the metal, then taking out the workpiece, cooling the workpiece to room temperature in an oil cooling or salt bath cooling medium, and tempering the workpiece at 200 ℃ -300 ℃ for 2-4 h, wherein the functional oxide is selected from at least one of vanadium oxide and titanium oxide, and the functional salt is selected from one of vanadium salt and titanium salt.
  2. 2. The high-performance radial sealing sheet material for the rotary engine according to claim 1, wherein the Cr12MoV alloy tool steel comprises, by mass, 0.95% -1.05% of carbon, 11.5% -12.5% of chromium, 0.40% -0.60% of molybdenum, 0.45% -0.55% of vanadium, less than or equal to 0.40% of silicon, less than or equal to 0.40% of manganese, less than or equal to 0.030% of phosphorus, less than or equal to 0.030% of sulfur, and the balance iron.
  3. 3. The high-performance radial sealing sheet material for the rotary engine as claimed in claim 1, wherein the radial sealing sheet is provided with a pressurizing groove, the groove depth of the single pressurizing groove is controlled to be 15% -50% of the width of the sealing sheet, and the single groove width is controlled to be 1% -10% of the length of the radial sealing sheet.
  4. 4. The high-performance radial sealing sheet material for the rotary engine as claimed in claim 2, wherein the Cr12MoV alloy tool steel comprises, by mass, 0.95-1% of carbon, 12% of chromium, 0.5% of molybdenum, 0.5% of vanadium, less than or equal to 0.40% of silicon, less than or equal to 0.40% of manganese, less than or equal to 0.030% of phosphorus, less than or equal to 0.030% of sulfur, and the balance of Fe.
  5. 5. A high performance radial seal sheet material for rotary engines as set forth in claim 1 wherein the vanadium oxide comprises vanadium pentoxide, the vanadium salt comprises metavanadate, hexafluorovanadate, the titanium salt comprises titanium tetrachloride, and the titanium oxide comprises titanium dioxide.
  6. 6. The high-performance radial sealing sheet material for the rotary engine according to claim 1, wherein the salt bath vanadium/titanium infiltration method comprises immersing the sealing sheet in molten salt containing metal elements such as titanium and/or vanadium for 8-12 hours at a temperature of 950-980 ℃.
  7. 7. A high-performance radial sealing sheet material for a rotary engine according to claim 1, wherein the composite molten salt used in the salt bath titanizing consists of, by mass, 40% of sodium chloride, 50% of potassium chloride, 5% of sodium fluoride, 2% of sodium carbonate, 3% of titanium tetrachloride, or 50% of sodium chloride, 42% of potassium chloride, 3% of sodium fluoride, 2% of sodium carbonate and 3% of titanium dioxide.
  8. 8. The high-performance radial sealing sheet material for the rotary engine as claimed in claim 1, wherein the composite molten salt used in the salt bath vanadium infiltration comprises, by mass, 45% of sodium chloride, 48% of potassium chloride, 2% of sodium fluoride, 3% of sodium carbonate and 2% of ammonium metavanadate.
  9. 9. A high performance radial seal sheet material for a rotary engine as claimed in claim 1, wherein the mechanical polishing and surface cleaning treatment is carried out sufficiently before the salt bath to a surface roughness Rz of 0.2 or less; after the diffusion process metal carbide coating treatment is completed, carrying out subsequent heat treatment, wherein the subsequent heat treatment comprises a tempering process, and the parameters range is as follows: the temperature is 220 ℃ to 250 ℃, the heat preservation time is 2.5 to 3.5 hours, the temperature rising rate is 3 ℃ to 5 ℃ per minute, and the cooling mode is natural cooling or slow cooling; the surface hardness of the obtained sealing sheet is more than or equal to HV2000; The coefficient of friction ranges from 0.10 to 0.18 in the dry friction test at 180 ℃ high temperature.
  10. 10. The high-performance radial seal sheet material for a rotary engine according to claim 1, wherein the wear rate is (1.0 to 3.0). Times.10 -6 mm 3/(N.m) in 180 ℃ dry friction condition; the sealing plate can be normally and stably used at 500 ℃ and 8000 RPM; the normal service temperature of the obtained sealing sheet can reach 450-500 ℃, and the short-time peak temperature can bear 550 ℃; the resulting sealing panel was subjected to a sealing pressure in the range of 1.01MPa to 3.5 MPa.

Description

High-performance radial seal sheet material for rotor engine Technical Field The invention relates to the technical field of rotary engines, in particular to a radial sealing sheet material with high wear resistance and self lubrication. Background The rotor engine is widely applied to the fields of aviation, automobiles and the like due to compact structure and stable power output. The radial sealing piece plays a sealing role between the rotor and the cylinder, and the performance of the radial sealing piece directly influences the reliability and the service life of the engine. Currently, existing sealing sheet materials are prone to wear and deformation under high temperature, high pressure and high speed conditions, and development of a sealing material that maintains high hardness, wear resistance and self-lubricity under severe working conditions is highly demanded. Cr12MoV (alloy tool steel) is suitable for cold work die steel, and the hardenability, hardness of quenching and tempering, wear resistance and strength of the steel are all higher than those of Cr 12. It can also be used as various cold stamping dies and tools under complex shapes and heavy working conditions, such as punching female dies, trimming dies, edge rolling dies, deep drawing dies of steel plates, circular saws, standard tools and gauges, thread rolling dies, and the like. However, cr12MoV belongs to high-carbon high-chromium ledeburitic steel, has high carbide content, accounts for about 20 percent, is often in a strip shape or net shape and unevenly distributed, has serious segregation, and the conventional heat treatment is difficult to change the segregation condition of the carbide, so that the mechanical property of the steel and the service life of a die are seriously influenced. In order to improve the mechanical properties and the service life, some treatment methods are tried, wherein the treatment method comprises salt bath vanadium infiltration treatment. The carbide diffusion layer can be obtained on the surface through the neutral salt bath vanadium diffusion treatment, has uniform structure, good continuity and compactness, uniform thickness and compact structure, has very high microhardness and high wear resistance, and greatly improves the performances of surface hardness, wear resistance, anti-adhesion and the like. The generated carbide contains vanadium carbide VC, the solubility of VC in austenite is higher than that of VC in ferrite, VC is separated out from ferrite along with the reduction of temperature, so that the alloy is strengthened and the grains are refined, and the compound layer shows higher hardness. In the prior art, some attempts have been made to use Cr12MoV alloy tool steel as a sealing material, such as the application of Cr12MoV as a sealing ring manufacturing material in patent CN104046751A, and a heat treatment process method of the sealing ring is also involved, specifically, cr12MoV is stretched into a sealing ring conforming to the size, and the sealing ring is manufactured into a finished product through a quenching treatment method and a tempering treatment method, wherein the quenching treatment method is that the quenching temperature is 1050 ℃, the quenching heat preservation time is 10 minutes, the tempering treatment method is that the tempering temperature is 550 ℃, and the tempering heat preservation time is 2-4 hours, so that the hardness of the Cr12MoV sealing ring is 48-50 HRC. However, the technology for preparing a high-performance radial sealing sheet of a rotary engine by preparing a metal carbide coating by a diffusion method and combining with subsequent treatment on Cr12MoV alloy tool steel is still well documented in the prior art. Disclosure of Invention The invention aims to provide a high-performance radial sealing sheet material, which improves the wear resistance and service life of a sealing sheet and meets the severe working condition requirement of a rotor engine by selecting Cr12MoV alloy and performing diffusion method metal carbide coating treatment. The invention relates to a high-performance radial sealing sheet material for a rotary engine, which comprises a base material and a metal carbide coating, wherein the base material comprises Cr12MoV alloy tool steel, and the metal carbide coating is attached to the base material by a diffusion method and forms metallurgical bonding with the base material. As the research and development are in progress, the base material can be ceramic material, but the practical application also comprises a long section of ceramic material and a short section of steel material. The radial sealing plate is provided with the pressurizing groove, so that the sealing pressure distribution is optimized, the weight of the radial sealing plate is reduced, friction vibration and noise are reduced, the service life of the sealing plate is prolonged, and the reliability and the silencing performance of the engine are improved. The