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CN-122010583-A - Non-oxide composite reinforced slag ladle spray coating and preparation method thereof

CN122010583ACN 122010583 ACN122010583 ACN 122010583ACN-122010583-A

Abstract

The invention discloses a non-oxide composite reinforced slag pot spray coating and a preparation method thereof, and relates to the technical field of metallurgical auxiliary materials, wherein the coating comprises, by weight, 10-15 parts of polysilazane modified phenolic resin, 3-5 parts of anhydrous potassium sodium borate, 2-4 parts of nano silicon carbide sol, 2 parts of silicon nitride micro powder, 0.5-2 parts of coated microcapsule foaming agent, 66-77.5 parts of non-oxide main body reinforced phase, 1-2 parts of suspending agent and 1-2 parts of slag resistance auxiliary agent, the non-oxide main body reinforced phase is formed by mixing black silicon carbide and micro-expanded crystalline flake graphite according to the weight ratio of 9:4.

Inventors

  • HU SAI
  • GONG CHENGCHENG

Assignees

  • 淄博昌河新材料科技有限公司

Dates

Publication Date
20260512
Application Date
20260408

Claims (10)

  1. 1. The non-oxide composite reinforced slag pot spray paint is characterized by comprising, by weight, 10-15 parts of polysilazane modified phenolic resin, 3-5 parts of anhydrous potassium sodium borate, 2-4 parts of nano silicon carbide sol, 2 parts of silicon nitride micro powder, 0.5-2 parts of coated microcapsule foaming agent, 66-77.5 parts of non-oxide main reinforcing phase, 1-2 parts of suspending agent and 1-2 parts of slag resistance auxiliary agent; the non-oxide main reinforcing phase is formed by mixing black silicon carbide and micro-expanded crystalline flake graphite according to the weight ratio of 9:4.
  2. 2. The non-oxide composite reinforced slag pot spray coating according to claim 1, wherein the polysilazane modified phenolic resin is prepared by grafting reaction of thermosetting phenolic resin and polymethylsilazane according to the weight ratio of 4:1, the softening point of the thermosetting phenolic resin is 80-100 ℃, the free phenol content is less than or equal to 5wt%, the number average molecular weight of the polymethylsilazane is 1000-3000g/mol, the polysilazane modified phenolic resin is a viscous solid at 25 ℃, and the viscosity is 5000-10000mPa s.
  3. 3. The non-oxide composite reinforced slag ladle spray coating according to claim 1, wherein the nano silicon carbide sol is beta-crystal silicon carbide nano sol, the solid content is 30% -40%, the particle size of the silicon carbide nano particles is 20-50nm, the pH value of the sol is 7-9, no alcohol dispersant exists, the anhydrous potassium sodium borate is a compound of potassium borate and sodium borate according to the weight ratio of 1:1-2:1, the particle size is 100-200 meshes, the silicon carbide nano sol does not contain crystal water, and the ignition decrement at 800 ℃ is less than or equal to 0.5wt%.
  4. 4. The non-oxide composite reinforced slag ladle spray coating according to claim 1, wherein the coated microcapsule foaming agent is of a core-shell structure, the wall material is gas phase SiO 2 or light CaCO 3 , the thickness of the wall material is 2-4 mu m, the inner core is one of n-butane, n-pentane or light magnesium carbonate, the inner core accounts for 40% -60% of the total weight of the microcapsule, and the integral particle size of the microcapsule is 50-100 mu m.
  5. 5. The non-oxide composite reinforced slag pot spray paint according to claim 1 is characterized in that the black silicon carbide is 250 mesh superfine powder, the carbon content is less than or equal to 0.5 percent, the free silicon content is less than or equal to 0.3 percent, the flake thickness of the micro-expanded flake graphite is 1-5 mu m, the particle size is 200-325 meshes, the fixed carbon content is more than or equal to 99 percent, the ash content is less than or equal to 0.5 percent, the suspending agent is melt fiber RSU, the fiber length is 10-50 mu m, the fiber diameter is 1-3 mu m, the slag resistance auxiliary agent is alpha crystal alumina superfine powder, the particle size is less than or equal to 1 mu m, and the particle size distribution D50 is 0.3-0.5 mu m.
  6. 6. A method for preparing a non-oxide composite reinforced slag pot spray coating, which is used for preparing the non-oxide composite reinforced slag pot spray coating according to any one of claims 1 to 5, and is characterized by comprising the following specific steps: S1, preparing modified resin, namely adding phenolic resin and polysilazane into a nitrogen-protected reaction kettle according to the weight ratio of 4:1, regulating the temperature in the kettle to 120-150 ℃, stirring at the speed of 200-300r/min for 2-3h for grafting reaction, naturally cooling to normal temperature after the reaction is finished, and sealing for later use after the polysilazane modified phenolic resin is prepared; S2, homogenizing dry materials, namely weighing anhydrous potassium sodium borate, silicon nitride micropowder, coated microcapsule foaming agent, non-oxide main reinforcing phase, suspending agent and slag resistance auxiliary agent according to parts by weight, and putting all dry materials into high-speed mixing equipment for stirring and mixing to obtain a non-oxide dry material mixture with uniform components; S3, liquid-solid pulping, namely adding polysilazane modified phenolic resin and nano silicon carbide sol into a non-oxide dry material mixture, adding metallurgical hot closed circulating water, stirring at a medium speed to enable liquid phase and dry materials to be primarily fused, then lifting the stirring speed to 3000r/min for high-speed stirring, regulating and controlling the water adding amount to enable the volume density of slurry to be 1.2-1.3g/cm 3 and the viscosity to be 20-25S, standing and defoaming after stirring is completed, transferring the prepared spraying slurry to a special slurry storage tank, continuously stirring the slurry at a low speed, detecting the volume density and the viscosity of the slurry periodically, and performing targeted fine adjustment on the slurry with fluctuation of performance.
  7. 7. The preparation method of the non-oxide composite reinforced slag pot spray paint according to claim 6, wherein in the step S1, before the phenolic resin is taken, the phenolic resin is dried at 60-80 ℃ for 2-3 hours, polysilazane is added into a reaction kettle at a dropping rate of 5-10mL/min, the purity of nitrogen introduced into the reaction kettle is more than or equal to 99.99%, the ventilation rate is 0.5-1m 3 /h and the continuous ventilation time is not less than 30min, the heating rate of the reaction kettle is 5-8 ℃/min, and the cooling stage keeps stirring at 50-80r/min to normal temperature.
  8. 8. The preparation method of the non-oxide composite reinforced slag ladle spray coating material is characterized in that in the step S2, anhydrous potassium sodium borate, silicon nitride micro powder, black silicon carbide, micro-expanded crystalline flake graphite and slag resistance auxiliary agent are dried for 4-6 hours at 100-120 ℃, the coated microcapsule foaming agent is screened by a screen, the stirring speed of high-speed mixing equipment is 1500-2000r/min, the mixing time is 10-15min, and the mixed dry material is screened by the screen again.
  9. 9. The preparation method of the non-oxide composite reinforced slag ladle spray coating material according to claim 6, wherein in the step S3, the medium-speed stirring rate of preliminary fusion of the liquid phase and the dry material is 800-1000r/min, the stirring time is 5-8min, 70% of total water consumption is added into metallurgical hot-closed circulating water, the rest water is added in batches of 3-5, the duration of high-speed stirring is 15-20min, the temperature of the material in a pulping machine is controlled at 25-35 ℃, the standing and defoaming time is 2-3min, and no additional stirring or vibration operation is performed in the standing process.
  10. 10. The preparation method of the non-oxide composite reinforced slag pot spray paint is characterized in that in the step S3, a special slurry storage pot is provided with a constant-temperature jacket and an anchor stirring paddle, the temperature of slurry is controlled to be 20-30 ℃ through the constant-temperature jacket, the stirring speed of the stirring paddle is 50-80r/min, metallurgical hot closed circulating water is added along the inner wall of the slurry storage pot when the viscosity of the slurry is high, the slurry is stirred for 1-2min at the speed of 100-150r/min, the slurry is taken from a discharge hole at the bottom of the slurry storage pot, and a stirring device is started to stir for 5-8min before taking the slurry.

Description

Non-oxide composite reinforced slag ladle spray coating and preparation method thereof Technical Field The invention relates to the technical field of metallurgical auxiliary materials, in particular to a non-oxide composite reinforced slag pot spray coating and a preparation method thereof. Background In the production process of the metallurgical industry, the slag pot is used as core equipment for bearing high-temperature slag, and is in the severe working conditions of high temperature, slag scouring erosion and temperature shock for a long time, the protection treatment of the inner wall of the slag pot directly relates to the service life, production efficiency and production safety of the equipment, a protective coating is formed on the inner wall of the slag pot in a mode of spraying special spray paint for improving the slag resistance, thermal shock resistance and high temperature resistance of the slag pot in the industry, so that the direct contact of slag and a slag pot substrate is isolated, the loss of the equipment is reduced, the non-oxide material has excellent high-temperature performance, chemical stability and slag erosion resistance, and becomes an important raw material in the research and development and application of slag pot spray paint, and the research and optimization of related non-oxide composite enhanced spray paint are also an important research direction in the field of metallurgical auxiliary materials, and the practical requirements of the industry on the high performance and long service life of the slag pot protective material are met. The traditional slag pot spray paint has a plurality of defects in component design and performance, the bonding system of part of the spray paint is easy to be pyrolyzed and softened under a high-temperature environment, so that the bonding strength of the coating and a slag pot substrate is reduced, the problems of cracking and falling of the coating are easy to occur, continuous effective protection cannot be formed, the slag erosion resistance and the permeation resistance of part of the spray paint are insufficient, the high-temperature slag is easy to scour and erode the coating, even the coating is damaged by penetrating to the substrate, meanwhile, the thermal shock resistance of the traditional spray paint is poor, the coating is easy to crack due to thermal stress under the working condition of sudden temperature rising and falling, the protection effect is further reduced, in addition, the dispersing and fusing of each component by the traditional spray paint is insufficient, the uneven component condition is easy to occur, the slurry spraying property is poor, the coating performance consistency is low, the storage stability of part of the spray paint is poor, sedimentation and layering are easy to occur, and the difficulty of site construction is increased. Disclosure of Invention The invention aims to make up the defects of the prior art and provides a non-oxide composite reinforced slag pot spray coating and a preparation method thereof, wherein the spray coating uses polysilazane modified phenolic resin as a bonding system, is compounded with functional aids such as anhydrous potassium sodium borate, nano silicon carbide sol and the like, is matched with a non-oxide main reinforced phase consisting of black silicon carbide and micro-expanded crystalline flake graphite, has scientific component proportion and function coordination, is prepared by three steps of modified resin preparation, dry material homogenization and liquid-solid pulping, realizes full dispersion and fusion of the components through nitrogen protection grafting, high-temperature drying, gradient stirring, constant-temperature storage and other refining processes, accurately regulates and controls the slurry performance, has excellent high-temperature cohesiveness, slag erosion resistance and thermal shock resistance, has good slurry storage and spray coating performance, is convenient to construct, can form a stable protective coating on the inner wall of a slag pot, prolongs the service life of equipment, and is suitable for industrial production and construction requirements in the metallurgical industry, and has significant application value. The invention provides a non-oxide composite reinforced slag pot spray coating, which comprises, by weight, 10-15 parts of polysilazane modified phenolic resin, 3-5 parts of anhydrous potassium sodium borate, 2-4 parts of nano silicon carbide sol, 2 parts of silicon nitride micro powder, 0.5-2 parts of coated microcapsule foaming agent, 66-77.5 parts of non-oxide main reinforcing phase, 1-2 parts of suspending agent and 1-2 parts of slag resistance auxiliary agent; the non-oxide main reinforcing phase is formed by mixing black silicon carbide and micro-expanded crystalline flake graphite according to the weight ratio of 9:4. Further, the polysilazane modified phenolic resin is prepared by grafting reaction of th