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CN-121976140-A - High-temperature corrosion-resistant thermal spraying material for heating surface of boiler and preparation method thereof

CN121976140ACN 121976140 ACN121976140 ACN 121976140ACN-121976140-A

Abstract

The invention discloses a thermal spraying material for preventing a heating surface of a boiler from high-temperature corrosion, which comprises, by mass, 45-49% of Cr, 1.5-2.5% of Ti, 0.1-5% of active elements and the balance of Ni, wherein the active elements are one or more of Fe, mn, si, zr, V, mo, B. The thermal spraying material greatly reduces the void ratio of the coating by regulating and controlling the composition and the content of the components, and improves the strength, the wear resistance, the high temperature resistance and the corrosion resistance.

Inventors

  • Cheng Liangqiao
  • ZHOU HONG
  • FU QIANG
  • Sun Duankai
  • HUANG JIAN
  • ZENG XINGWEN

Assignees

  • 贵州省习水鼎泰能源开发有限责任公司

Dates

Publication Date
20260505
Application Date
20251230

Claims (10)

  1. 1. The thermal spraying material for preventing the boiler heating surface from being corroded at high temperature is characterized by comprising the following components in percentage by mass: 45-49% of Cr, 1.5-2.5% of Ti, 0.1-5% of active element and the balance of Ni; The active element is one or more of Fe, mn, si, zr, V, mo, B.
  2. 2. The thermal spraying material for preventing the high-temperature corrosion of the heating surface of the boiler according to claim 1, wherein the thermal spraying material comprises, by mass, 45-49% of Cr, 1.5-2.5% of Ti, 0.1-0.5% of Fe, 0.5-1% of Mn, 1-1.5% of Si and the balance of Ni.
  3. 3. The thermal spraying material for preventing the high-temperature corrosion of the heating surface of the boiler according to claim 1, wherein the thermal spraying material comprises, by mass, 45-49% of Cr, 1.5-2.5% of Ti, 0.5-1% of C, 1-1.5% of Si, 0.5-1% of Zr and the balance of Ni.
  4. 4. The thermal spraying material for preventing the boiler heating surface from being corroded at high temperature according to claim 1, wherein the thermal spraying material comprises, by mass, 45-49% of Cr, 1.5-2.5% of Ti, 1.5-2.5% of Zr1.5%, 0.1-0.5% of V, 0.5-1.5% of B and the balance of Ni.
  5. 5. The thermal spraying material for preventing the high-temperature corrosion of the heating surface of the boiler according to claim 1, wherein the thermal spraying material comprises, by mass, 45-49% of Cr, 1.5-2.5% of Ti, 1-2% of Zr, 0.2-0.8% of Mo and the balance of Ni.
  6. 6. The thermal spraying material for preventing the boiler heating surface from being corroded at high temperature according to claim 1, wherein the thermal spraying material comprises, by mass, 45-49% of Cr, 1.5-2.5% of Ti, 0.2-0.5% of Si, 0.5-1% of Zr, 0.5-1.5% of Al, 0.2-1.5% of B and the balance of Ni.
  7. 7. A method for preparing a thermal spraying material for preventing high-temperature corrosion of a heating surface of a boiler according to any one of claims 1 to 6, wherein the preparation method comprises the following steps: S1, smelting the raw material components in proportion in a mixed atmosphere of ammonia and argon, preserving heat for 3-4 hours, and then casting into an alloy ingot; s2, forging the alloy ingot obtained in the step S1 to obtain a blank; s3, performing rotary forging on the blank obtained in the step S2 on a rotary forging machine to obtain a wire; S4, removing oxide skin and rust matters on the surface of the wire material obtained in the step S3 through chemical cleaning; s5, carrying out 1150 ℃ dehydrogenation annealing treatment on the wire material cleaned in the step S4.
  8. 8. The method for preparing the thermal spraying material for preventing high temperature corrosion of a heated surface of a boiler according to claim 7, wherein the volume ratio of ammonia gas to argon gas in the step S1 is 1:5-6.
  9. 9. The method for preparing a thermal spraying material for preventing high temperature corrosion of a heated surface of a boiler according to claim 7, wherein the forging and rotary forging temperatures are 1150-1250 ℃.
  10. 10. The method for preparing the thermal spraying material for preventing high temperature corrosion of a heated surface of a boiler according to claim 7, wherein in the step S2, the diameter of the wire is 1.8±1mm.

Description

High-temperature corrosion-resistant thermal spraying material for heating surface of boiler and preparation method thereof Technical Field The invention relates to the technical field of spray materials, in particular to a thermal spray material for preventing a heating surface of a boiler from high-temperature corrosion and a preparation method thereof. Background The boiler 'four tubes' (namely a water wall tube, a superheater tube, a reheater tube and an economizer tube) cover all heating surfaces of the boiler, the inside of the boiler is subjected to the pressure of working media and the effects of certain chemical components, the outside of the boiler is subjected to the environmental effects of high temperature, corrosion and abrasion, failure and leakage problems are easy to occur, serious threat is formed to the stable operation of a unit, the completion of power generation indexes is influenced, economic benefits are reduced, and the normal scheduling of a power grid is directly influenced. Fly ash abrasion and mechanical abrasion of a heating surface of the pulverized coal boiler are main reasons for influencing long-term safe operation of the boiler, and the wall of the boiler is thinned due to long-time hand abrasion, so that the tube leaks due to strength reduction. In addition, alkali metal in ash is biochemically treated at high temperature and generates compound sulfate with SO 3 in flue gas, and the compound sulfate is condensed on the pipe wall to damage the oxide film on the pipe wall surface, namely high-temperature corrosion occurs. At present, the high-temperature corrosion-resistant paint for the boiler heating surface of the thermal power plant is mainly inorganic salt paint, and the paint has good high-temperature resistance and good high-temperature strength, but because the paint is water-soluble paint, the porosity of the coating is higher (the porosity is more than 3 percent) after the paint is solidified, the isolating effect of the coating is weakened due to the existence of the coating pores, and corrosive medium can pass through the coating from the pores to a substrate to corrode the coating. Therefore, how to select the composition of the four-pipe spraying material so as to improve the wear resistance, the high-temperature corrosion resistance and the sulfate corrosion resistance of the surfaces of the four pipes of the boiler is extremely important. Disclosure of Invention In view of the defects of the prior art, the invention aims to provide a thermal spraying material for preventing a heating surface of a boiler from high-temperature corrosion and a preparation method thereof, which are used for solving the problems of leakage of four pipes of the boiler due to abrasion and corrosion, high porosity of the existing coating, high-temperature resistance, corrosion resistance and insufficient strength. The invention provides a thermal spraying material for preventing a heating surface of a boiler from high-temperature corrosion, which comprises the following components in percentage by mass: 45-49% of Cr, 1.5-2.5% of Ti, 0.1-5% of active element and the balance of Ni; The active element is one or more of Fe, mn, si, zr, V, mo, B. Preferably, the thermal spraying material comprises 45-49% of Cr, 1.5-2.5% of Ti, 0.1-0.5% of Fe, 0.5-1% of Mn, 1-1.5% of Si and the balance of Ni. Preferably, the thermal spraying material comprises 45-49% of Cr, 1.5-2.5% of Ti, 0.5-1% of C, 1-1.5% of Si, 0.5-1% of Zr and the balance of Ni in percentage by mass. Preferably, the thermal spraying material comprises 45-49% of Cr, 1.5-2.5% of Ti, 1.5-2.5% of Zr, 0.1-0.5% of V, 0.5-1.5% of B and the balance of Ni. Preferably, the thermal spraying material comprises 45-49% of Cr, 1.5-2.5% of Ti, 1-2% of Zr, 0.2-0.8% of Mo and the balance of Ni. Preferably, the thermal spraying material comprises 45-49% of Cr, 1.5-2.5% of Ti, 0.2-0.5% of Si, 0.5-1% of Zr, 0.5-1.5% of Al, 0.2-1.5% of B and the balance of Ni. The invention also provides a preparation method of the thermal spraying material for preventing the boiler heating surface from high-temperature corrosion, which comprises the following steps: S1, smelting the raw material components in proportion in a mixed atmosphere of ammonia and argon, preserving heat for 3-4 hours, and then casting into an alloy ingot; s2, forging the alloy ingot obtained in the step S1 to obtain a blank; s3, performing rotary forging on the blank obtained in the step S2 on a rotary forging machine to obtain a wire; S4, removing oxide skin and rust matters on the surface of the wire material obtained in the step S3 through chemical cleaning; s5, carrying out 1150 ℃ dehydrogenation annealing treatment on the wire material cleaned in the step S4. Preferably, in the step S1, the volume ratio of ammonia gas to argon gas is 1:5-6. Preferably, in the step S2, a blank of 40×40mm is forgeable, but the present invention is not limited to this size. Preferably, the forging and swaging