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CN-118561622-B - For MoSi2Gradient YTO coating material on heating element and preparation method thereof

CN118561622BCN 118561622 BCN118561622 BCN 118561622BCN-118561622-B

Abstract

The invention discloses a gradient YTO coating material for MoSi 2 heating element and a preparation method thereof, relating to the technical field of high-temperature antioxidation coating, according to the invention, a gradient YTO coating consisting of YTa 3 O 9 、YTaO 4 、Y 3 TaO 7 from inside to outside is prepared on the MoSi 2 heating element sequentially by adopting a sol-gel method and an electrophoretic deposition method, and the coating has good thermal matching property with a matrix and high binding force. According to the invention, after the high-temperature-resistant oxidation-resistant gradient YTO coating prepared by the MoSi 2 heating element is examined by oxygen-acetylene flame at 1900 ℃ for 120min, the coating and the MoSi 2 heating element are intact and have no damage, a glass film does not appear on the surface, the coating can well protect a substrate, the service temperature of the MoSi 2 heating element is improved, and the service life of the MoSi 2 heating element is prolonged. The YTO coating preparation process is simple in flow, simple in equipment, low in production cost and easy to operate.

Inventors

  • TAN DUNQIANG
  • WANG YUQING
  • ZHONG JIANHUI

Assignees

  • 南昌大学

Dates

Publication Date
20260512
Application Date
20240419

Claims (8)

  1. 1. A gradient YTO coating material is characterized in that by solid-dissolving yttrium salt and tantalum salt, each gradient forms a single-phase compound with a monoclinic crystal structure on a substrate, and the phase component of the single-phase compound is YTa 3 O 9 、YTaO 4 or Y 3 TaO 7 ; The matrix adopts MoSi 2 heating elements; The preparation method of the coating material comprises the following steps: s1, weighing raw materials according to the phase components, wherein the raw materials comprise yttrium salt and tantalum salt; s2, dissolving the raw materials in the step S1 in a solvent, adding a catalyst to prepare a precursor solution, and aging for later use; S3, preparing a gradient YTO coating with a single phase on the surface of the matrix by adopting a sol-gel impregnation pulling method or an electrophoretic deposition method to obtain a preform; and S4, sintering the prefabricated product obtained in the step S3 under the protection of argon, heating to 1650 ℃ and calcining for 2-10 hours at constant temperature to obtain the finished product.
  2. 2. A method of preparing the gradient YTO coating material of claim 1, comprising the steps of: s1, weighing raw materials according to the phase components, wherein the raw materials comprise yttrium salt and tantalum salt; s2, dissolving the raw materials in the step S1 in a solvent, adding a catalyst to prepare a precursor solution, and aging for later use; S3, preparing a gradient YTO coating with a single phase on the surface of the matrix by adopting a sol-gel impregnation pulling method or an electrophoretic deposition method to obtain a preform; and S4, sintering the prefabricated product obtained in the step S3 under the protection of argon, heating to 1650 ℃ and calcining for 2-10 hours at constant temperature to obtain the finished product.
  3. 3. The method for preparing a gradient YTO coating material according to claim 2, wherein in step S1, at least the following technical features are included: The yttrium salt comprises at least one of yttrium acetate, yttrium isopropoxide, yttrium acetylacetonate and yttrium nitrate hexahydrate; The tantalum salt comprises at least one of tantalum ethoxide, tantalum pentachloride, tantalum n-butoxide and tantalum isopropoxide; The purity of the raw materials is more than or equal to 99.99 percent, and the molar ratio of the raw materials Y to Ta is 1-3:1-3.
  4. 4. The method for preparing a gradient YTO coating material according to claim 2, wherein in step S2, at least the following technical features are included: Ethanol is adopted as the solvent, glacial acetic acid is adopted as the catalyst, the aging temperature is 20-25 ℃, and the aging time is 24-48h.
  5. 5. The method for preparing a gradient YTO coating material according to claim 2, wherein in the step S3, the sol-gel dipping and pulling method is specifically that a substrate is dipped in a precursor solution, the substrate is pulled out at a speed of 0.8-1cm/min after dipping for 60-180S, then dried, and the steps of pulling and drying are repeated to prepare the substrate with a multi-layer film layer.
  6. 6. The method for preparing a gradient YTO coating material according to claim 2, wherein the electrophoretic deposition method comprises the following steps: The method comprises the steps of taking a stainless steel mesh as an anode, taking a substrate as a cathode, carrying out deposition on the substrate at a polar distance of 1-3 cm and a deposition voltage of 80-120V for 1-5 min, adopting constant-pressure electrophoretic deposition, drying, and repeating the deposition and drying steps to obtain the substrate with the multilayer film.
  7. 7. The method for preparing the gradient YTO coating material according to claim 5 or 6, wherein the drying mode is that a substrate is placed in a vacuum drying oven and dried for 5-10 min at 70-90 ℃.
  8. 8. The method for preparing the gradient YTO coating material according to claim 2, wherein in the step S4, the temperature rising rate of sintering is 20-150 ℃ at 3 ℃ per minute, 150-1200 ℃ at 10 ℃ per minute, and 1200-1650 ℃ at 3 ℃ per minute.

Description

Gradient YTO coating material for MoSi 2 heating element and preparation method thereof Technical Field The invention relates to the technical field of high-temperature antioxidant coatings, in particular to a gradient YTO coating material for MoSi 2 heating elements and a preparation method thereof. Background With the rapid development of industrial production, the use requirement of the high-temperature heating element is improved. At present, domestic MoSi 2 heating elements can be used for a long time at 1700 ℃, and the highest use temperature of imported MoSi 2 heating elements can reach 1850 ℃. In order to increase the service temperature of the domestic MoSi 2 heating element and prolong the service life of the domestic MoSi 2 heating element in a high-temperature oxidation environment, a high-temperature oxidation-resistant coating is prepared on the surface of the domestic MoSi 2 heating element. The spherical thin-wall hollow shell nanometer fully-stable tetragonal YSZ powder is used in the Chinese patent CN202310741979.7 to prepare a YSZ coating by an atmospheric plasma spraying technology, but the inside of the coating has more vertical cracks and cannot well protect a substrate, and the rare earth tantalate coating prepared by an APS method in the Chinese patent CN202010887388.7 has complex process flow and expensive equipment. Disclosure of Invention The invention aims to at least solve one of the technical problems in the prior art and provides a gradient YTO coating material and a preparation method thereof. The technical scheme of the invention is as follows: a gradient YTO coating material forms a single-phase compound having a monoclinic crystal structure on a substrate by solid-dissolving yttrium salt and tantalum salt, each gradient having a phase composition of YTa 3O9、YTaO4 or Y 3TaO7. As a preferred embodiment of the present invention, the method comprises the steps of: S1, weighing raw materials according to the phase components, wherein the raw materials comprise yttrium salt and tantalum salt; s2, dissolving the raw materials in the step S1 in a solvent, adding a catalyst to prepare a precursor solution, and aging for later use; S3, preparing a gradient YTO coating with a single phase on the surface of the matrix by adopting a sol-gel impregnation pulling method or an electrophoretic deposition method to obtain a preform; and S4, sintering the prefabricated product obtained in the step S3 under the protection of argon, heating to 1650 ℃ and calcining for 2-10 hours at constant temperature to obtain the finished product. As a preferred embodiment of the present invention, step S1 at least includes the following technical features: The yttrium salt comprises at least one of yttrium acetate, yttrium isopropoxide, yttrium acetylacetonate and yttrium nitrate hexahydrate; The tantalum salt comprises at least one of tantalum ethoxide, tantalum pentachloride, tantalum n-butoxide and tantalum isopropoxide; The purity of the raw materials is more than or equal to 99.99 percent, and the molar ratio of the raw materials Y to Ta is 1-3:1-3. As a preferred embodiment of the present invention, step S2 at least includes the following technical features: Ethanol is adopted as the solvent, glacial acetic acid is adopted as the catalyst, the aging temperature is 20-25 ℃, and the aging time is 24-48h. In the step S3, the sol-gel dipping and pulling method specifically comprises the steps of dipping a substrate in a precursor solution, dipping for 60-180 seconds, pulling out the substrate at a speed of 0.8-1cm/min, drying, and repeating the steps of pulling and drying to obtain the substrate with the multilayer film. As a preferred embodiment of the present invention, the electrophoretic deposition method is specifically as follows: The method comprises the steps of taking a stainless steel mesh as an anode, taking a substrate as a cathode, carrying out deposition on the substrate at a polar distance of 1-3 cm and a deposition voltage of 80-120V for 1-5 min, adopting constant-pressure electrophoretic deposition, drying, and repeating the deposition and drying steps to obtain the substrate with the multilayer film. As a preferable scheme of the invention, the drying mode is specifically that the substrate is placed in a vacuum drying oven and dried for 5-10 min at 70-90 ℃. As a preferable scheme of the invention, in the step S4, the temperature rising rate of sintering is that the temperature rising is 20-150 ℃ at 3 ℃ per minute, the temperature rising is 150-1200 ℃ at 10 ℃ per minute, and the temperature rising is 1200-1650 ℃ at 3 ℃ per minute. As a preferred embodiment of the invention, a MoSi 2 heating element is used as the substrate. The beneficial effects of the invention are as follows: According to the gradient YTO coating material provided by the invention, yttrium salt and tantalum salt are in solid solution to form a single-phase compound with a monoclinic crystal structure, the phase compo