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CN-122013196-A - Method for removing oxide on surface of nickel-based superalloy blade

CN122013196ACN 122013196 ACN122013196 ACN 122013196ACN-122013196-A

Abstract

The invention provides a method for removing oxides on the surface of a nickel-based superalloy blade, which comprises the steps of pre-etching, main etching, post-treatment, cold water cleaning, neutralization, cold water cleaning, hot water cleaning, drying and checking the oxide removal effect on the surface of the blade and the surface of an inner cavity of the blade. According to the method, the oxide and the corrosive liquid are subjected to chemical reaction, so that the high-efficiency removal of dense metal oxides such as hafnium, nickel, chromium, titanium and the like on the inner cavity surface of the nickel-based superalloy blade and the inner cavity surface is realized.

Inventors

  • WANG HAO
  • LI XIN
  • LIU PU
  • WANG JUAN
  • ZHAO RUOBING

Assignees

  • 中航装甲科技有限公司

Dates

Publication Date
20260512
Application Date
20260113

Claims (10)

  1. 1. The method for removing the oxide on the surface of the nickel-based superalloy blade is characterized by comprising the following steps: Step one, pre-etching, namely immersing the blade in a low-concentration etching solution, wherein the low-concentration etching solution comprises hydrochloric acid and deionized water; Step two, main corrosion, namely immersing the blade in a high-concentration corrosive liquid, wherein the high-concentration corrosive liquid comprises acid liquid, complexing agent and deionized water; Step three, post-treatment, namely immersing the leaves in a complexing solution, wherein the complexing solution comprises a complexing agent and deionized water; step four, cleaning with cold water, namely immersing the blade in clean water to remove corrosive liquid on the surface of the blade; step five, neutralizing, namely immersing the blade in an alkaline solution to neutralize the residual corrosive liquid on the surface of the blade; step six, cleaning with cold water, namely immersing the blade in clean water to remove the residual alkaline solution on the surface of the blade; Step seven, cleaning with hot water, namely soaking the blade in clear water to remove the residual alkaline solution on the surface of the blade; step eight, drying, namely placing the leaves in a drying box for drying; and step nine, checking the oxide removal effect of the surfaces of the blades and the surfaces of the inner cavities of the blades.
  2. 2. The method for removing oxides on the surface of a nickel-base superalloy blade according to claim 1, wherein the mass concentration of hydrochloric acid in the first step is 5-10%, preferably the temperature of the corrosive liquid in the first step is 20-30 ℃ and the soaking time is 2-5 min.
  3. 3. The method for removing oxide on the surface of the nickel-base superalloy blade according to claim 1, wherein the acid solution in the second step is nitric acid; more preferably, the mass concentration of the acid solution in the second step is 20-30%.
  4. 4. The method for removing oxide on the surface of a nickel-base superalloy blade according to claim 1, wherein the complexing agent in the second step comprises one or more of hydrofluoric acid, citric acid, oxalic acid and ethylenediamine tetraacetic acid; More preferably, the mass concentration of the complexing agent in the second step is 1-10%.
  5. 5. The method for removing oxide on the surface of a nickel-based superalloy blade according to claim 1, wherein the temperature of the corrosive liquid in the second step is 25-40 ℃ and the soaking time is 1-2 min.
  6. 6. The method for removing oxide on the surface of the nickel-based superalloy blade according to claim 1, wherein the complexing agent in the third step is one or more of hydrofluoric acid, citric acid, oxalic acid and ethylenediamine tetraacetic acid; preferably, the mass concentration of the complexing agent in the third step is 1-5%; preferably, the temperature of the complexing liquid in the third step is 20-30 ℃ and the soaking time is 1-2 min.
  7. 7. The method for removing oxide on the surface of the nickel-base superalloy blade according to claim 1, wherein the water temperature in the fourth step is 20-30 ℃ and the soaking time is 3-5 min; Preferably, the temperature of the alkaline solution in the fifth step is 20-30 ℃ and the soaking time is 3-5 min; Preferably, in the fifth step, the alkaline solution is an aqueous solution of sodium carbonate or sodium hydroxide.
  8. 8. The method for removing oxide on the surface of a nickel-base superalloy blade according to claim 1, wherein the water temperature in the sixth step is 20-30 ℃ and the soaking time is 3-5 min.
  9. 9. The method for removing oxide on the surface of a nickel-base superalloy blade according to claim 1, wherein the water temperature in the seventh step is 60-90 ℃ and the soaking time is 3-5 min.
  10. 10. The method for removing oxide on the surface of a nickel-base superalloy blade according to claim 1, wherein the drying temperature in the eighth step is 80-100 ℃ and the drying time is 1-2 hours.

Description

Method for removing oxide on surface of nickel-based superalloy blade Technical Field The invention belongs to the technical field of superalloy blades, and particularly relates to a method for removing oxides on the surface of a nickel-based superalloy blade. Background In the manufacturing process of the nickel-based superalloy blade, high-temperature process links such as core removal and heat treatment can promote the formation of metal oxides such as hafnium, nickel, chromium, titanium and the like on the outer surface or the inner cavity surface of the blade, and the metal oxides have complex components and various adverse effects. From a performance standpoint, oxides can reduce the surface finish of the blade, affect its aerodynamic performance, cause increased airflow disturbances, and affect the operating efficiency of the engine or gas turbine. From the subsequent processing angle, the oxide can interfere subsequent processes such as welding, coating and the like of the blade, influence the mechanical property and the coating adhesive force of the blade, and shorten the service life of the blade. At present, the method for removing the oxide on the surface of the nickel-based superalloy blade has a plurality of defects. On one hand, the existing mechanical removing method (such as manual polishing and sand blowing) is greatly influenced by human factors, so that the blade size is easily uneven, and the removing amount is generally 10-100 mu m, so that the blade size precision is adversely affected. In addition, the method relies on manual operation, when the blade is large in size or complex in structure, the single piece takes up to 1-2 hours, the production efficiency is low, meanwhile, the method is limited by accessibility of equipment and tools, and oxides on the surface of the inner cavity of the blade cannot be effectively removed for the narrow and bent inner cavity of the blade. On the other hand, although the chemical corrosion method can solve part of the problems of the mechanical method to a certain extent, the oxide is compact and difficult to corrode because of the high-temperature and high-pressure production process of the blade, and the common acid liquor can not achieve the effect of decomposing the oxide. Moreover, the formula of the corrosive liquid and the corrosion method are not properly controlled, and the conditions of incomplete oxide removal or excessive corrosion of a matrix are very easy to occur, so that the dimensional accuracy and mechanical properties of the blade are affected. Therefore, there is a need for a method that is efficient and effective in removing oxides from the surface of nickel-base superalloy blades without damaging the substrate. Disclosure of Invention In view of the above, the present invention aims to overcome the defects in the prior art, and proposes a method for removing oxides on the surface of a nickel-based superalloy blade. In order to achieve the above purpose, the technical scheme of the invention is realized as follows: a method for removing oxide on the surface of a nickel-based superalloy blade comprises the following steps: Step one, pre-etching, namely immersing the blade in a low-concentration etching solution, wherein the low-concentration etching solution comprises hydrochloric acid and deionized water; Step two, main corrosion, namely immersing the blade in a high-concentration corrosive liquid, wherein the high-concentration corrosive liquid comprises acid liquid, complexing agent and deionized water; Step three, post-treatment, namely immersing the leaves in a complexing solution, wherein the complexing solution comprises a complexing agent and deionized water; step four, cleaning with cold water, namely immersing the blade in clean water to remove corrosive liquid on the surface of the blade; step five, neutralizing, namely immersing the blade in an alkaline solution to neutralize the residual corrosive liquid on the surface of the blade; step six, cleaning with cold water, namely immersing the blade in clean water to remove the residual alkaline solution on the surface of the blade; Step seven, cleaning with hot water, namely soaking the blade in clear water to remove the residual alkaline solution on the surface of the blade; step eight, drying, namely placing the leaves in a drying box for drying; and step nine, checking the oxide removal effect of the surfaces of the blades and the surfaces of the inner cavities of the blades. The pre-corrosion, main corrosion and post-treatment can be independently used for removing the oxide on the surface of the nickel-based superalloy. In each step, the modes of mechanical stirring, ultrasonic vibration or gas boiling stirring can be added, so that the fluidity of the solution and the chemical reaction rate can be improved. The low-concentration corrosive liquid damages the binding force of the oxide and the nickel-based superalloy substrate and performs preliminary loosening on t