A ZTA particle surface corrosion method

Abstract

The present invention provides a ZTA particle surface etching method, comprising the following steps: ball milling (I) a smelted raw material, then placing it in an environment of 1000-1100°C for 0.5-1h, and then water quenching to obtain glass cullets; mixing the glass cullets, water, a dispersant, and an organic binder, and then ball milling (II) to obtain an etching slurry; immersing ZTA particles in the etching slurry, and then drying to obtain ZTA particles coated with glass micropowder; and hot etching the ZTA particles coated with glass micropowder at 850-950°C to obtain ZTA particles with corroded surfaces. The smelted raw material comprises 70-75wt% of Pyrex glass, 10-15wt% of sodium carbonate, 5-8wt% of sodium hexafluorosilicate, and 10-15wt% of zinc oxide.

Description

Technical Field

[0001] The invention relates to a surface corrosion process of zirconium oxide toughened alumina (ZTA) ceramic particles, in particular to a surface corrosion process of ZTA particles used for preparing ceramic iron-based composite wear-resistant materials, and belongs to the field of material surface treatment. Background Art

[0002] Particle-reinforced metal matrix composites (PRMMCs) are composites created by incorporating or incorporating a particle reinforcement into a metal matrix, resulting in a composite material that combines the high toughness and plasticity of the metal with the high hardness and high modulus of the reinforcing particles. PRMMCs offer low-cost reinforcements and a uniform microstructure. PRMMCs are isotropic and can be fabricated using traditional metalworking techniques such as casting, extrusion, and rolling.

[0003] Currently, the manufacturing methods for large-scale ceramic-steel composite wear-resistant materials are developing rapidly, primarily focusing on ceramic / iron-based composite materials reinforced with ZTA ceramic particles. Composite wear-resistant material companies such as Magotteaux of Belgium and VEGA of India have developed a range of ZTA ceramic / iron-based composite wear-resistant materials, including Duocast, Xwin, and Nexo. For example, composite grinding rollers and liners for vertical mills demonstrate the advantages of high working surface hardness, excellent wear resistance, and uniform surface finish after wear, significantly extending component life. These products have been widely used in industries such as cement production and thermal power generation, both domestically and internationally. The use of ZTA ceramic / iron-based composite wear-resistant materials has significantly extended the stable operation time of vertical mills, reduced unplanned equipment maintenance, significantly improved production efficiency, and reduced operating dynamic costs.

[0004] The current common method for preparing ZTA ceramic / iron-based composite wear-resistant materials involves dry-pressing ZTA particles of a specific size into a porous ceramic preform of the desired shape. This preform is then fixed to a designated location in a sand casting mold according to service requirements. A specially formulated molten iron alloy is then poured into the sand mold. The molten iron, through surface tension, fills the gaps between the ZTA particles, resulting in a ZTA / Fe-based composite material. This process presents certain challenges. For example, the contact angle between the ZTA particles and the molten iron alloy exceeds 80°, resulting in poor wettability. Furthermore, the ZTA particles and the iron matrix form a physical interface, and the relatively smooth surface of the ZTA particles results in a weak bond strength between the ZTA particles and the iron matrix, resulting in low flexural strength of the composite material. During service, especially under certain impact loads, the ZTA / Fe-based composite material is prone to cracking along the interface between the ZTA particles and the Fe matrix, causing fracture and compromising its performance. Summary of the Invention

[0005] The present invention provides a method for treating the surface corrosion of ZTA ceramic particles. This method can form rough, uneven pits on the surface of the treated ZTA ceramic particles. When the ZTA ceramic particles are composited with an iron matrix using a melt-casting method, the iron matrix effectively encapsulates the ZTA particles, enhancing the mechanical bonding between the ZTA particles and the iron matrix at the composite material interface. This improves the composite material's flexural strength and prevents abnormal fracture during service.

[0006] The present invention is implemented by adopting the following technical solutions.

[0007] A ZTA particle surface corrosion method comprises the following steps:

[0008] The smelted raw materials are ball-milled I, kept at 1000-1100°C for 0.5-1h, and then water-quenched to obtain glass fragments;

[0009] The glass fragments, water, dispersant and organic binder are mixed and ball milled to obtain a corrosion slurry;

[0010] Immersing ZTA particles in the etching slurry and then drying to obtain ZTA particles coated with glass powder;

[0011] The ZTA particles coated with glass powder are subjected to thermal etching at 850-950° C. to obtain ZTA particles with etched surfaces;

[0012] The smelting raw materials include 70-75 wt% of Pyrex glass, 10-15 wt% of sodium carbonate, 5-8 wt% of sodium hexafluorosilicate and 10-15 wt% of zinc oxide.

[0013] The ball-to-material ratio of the ball mill I is 1:0.5-1.5;

[0014] The grinding balls used in the ball mill I include corundum grinding balls;

[0015] The rotation speed of the ball mill I is 130-150 r / min;

[0016] The time of ball milling I is 30-60 min.

[0017] The organic binder includes a water-soluble hydroxy acrylic resin;

[0018] The dispersant includes sodium tripolyphosphate;

[0019] The weight ratio of the glass cullets, water, the organic binder and the sodium tripolyphosphate dispersant is (50-55): (35-40): (5-8): (2-3).

[0020] The ball-to-material ratio of the ball mill II is 1.2:1;

[0021] The grinding balls used in the ball mill II include zirconium oxide grinding balls;

[0022] The zirconia grinding balls include 40 wt% of zirconia grinding balls with a diameter of 20 mm and 60 wt% of zirconia grinding balls with a diameter of 10 mm;

[0023] The speed of the ball mill II is 240-260 r / min;

[0024] The time of ball milling II is 10-12 hours.

[0025] The heating rate of the thermal corrosion is 3-6°C / min;

[0026] The thermal corrosion time is 1-3 hours.

[0027] The ZTA particle surface corrosion method further comprises the steps of immersing the ZTA ceramic particles in a cleaning solution comprising sodium carbonate and O-25 type peregrine for ultrasonic cleaning, rinsing with water until neutral, and drying.

[0028] The concentration of sodium carbonate in the cleaning solution is 6-8wt%;

[0029] The concentration of O-25 type peregal in the cleaning solution is 1-2wt%;

[0030] The frequency used in the ultrasonic cleaning is 2000-4000 Hz.

[0031] The ZTA particle surface corrosion method further comprises the steps of cleaning the thermally corroded ZTA particles with a strong alkaline solution and then cleaning the particles in an HF solution under ultrasonic conditions.

[0032] The strong alkaline solution includes NaOH solution or KOH solution;

[0033] The concentration of the strong alkaline solution is 4-6 mol / L;

[0034] The cleaning temperature of the strong alkaline solution is 70-80°C;

[0035] The strong alkaline solution cleaning time is 4-6 hours in the early years;

[0036] The mass of the strong alkaline solution added for cleaning the thermally corroded ZTA particles does not exceed 20% of the mass of the strong alkaline solution.

[0037] The method comprises the step of ultrasonicating in a 10% HF solution at a frequency of 2000-4000 Hz for 1-2 hours.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The ZTA particle etching method provided herein can transform the originally smooth ZTA particle surface into a rough, uneven structure. A ZTA / Fe-based composite material prepared by casting using ZTA particles etched using the method provided herein (wherein the ZTA particles have a particle size of 12-14#, a volume fraction of 30%, the Fe matrix is ​​Mn13, and the casting temperature is 1500°C) exhibits an average three-point flexural strength of 340 MPa, which is over 20% higher than the flexural strength of a ZTA / Fe-based composite material prepared using conventional ZTA particles under the same conditions. In this ZTA / Fe-based composite material, the Fe matrix provides better encapsulation of the surface-etched ZTA ceramic particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Shows the surface morphology of ZTA particles before thermochemical etching treatment;

[0041] Figure 2 The surface morphology of the ZTA particles after corrosion at 900°C for 2 hours in Example 1 is shown;

[0042] Figure 3 The macroscopic morphology of ZTA particles after corrosion at 900°C for 2 hours in Example 1 is shown;

[0043] Figure 4 The fracture surface morphology of the ZTA / Fe-based composite material prepared from ZTA particles after corrosion at 900°C for 2 hours in Example 1 is shown;

[0044] Figure 5 The figure shows the fracture surface morphology of the commercially available ZTA particles that have not been corroded and the ZTA particles / Fe-based composite material. DETAILED DESCRIPTION

[0045] The technical solution of the present invention is to provide a surface corrosion process for ZTA ceramic particles, which comprises the following steps:

[0046] (1) Surface pretreatment of ZTA ceramic particles

[0047] Immerse ZTA ceramic particles of a specific size in a cleaning solution containing 6-8 wt% sodium carbonate and 1-2 wt% O-25 Peregal. Ultrasonic cleaning is performed at a frequency of 2000-4000 Hz for 20-40 minutes. Remove the ZTA ceramic particles, rinse with water until neutral, dry them in an oven at 60-80°C, and seal them in a bag for storage. This completes the surface cleaning of the ZTA particles.

[0048] (2) Preparation of special corrosion glass frit for ZTA ceramic particles

[0049] The raw material formula (mass percentage wt%) of the special corrosion glass frit for ZTA ceramic particles is:

[0050]

[0051] Specifically, the weighed raw materials were poured into a 400mm diameter corundum ball mill. 10mm diameter corundum balls were added at a 1:1 ball-to-material ratio. The mill was rotated at 130-150 rpm. The raw materials were ball milled for 30-60 minutes and then removed to obtain the smelting raw materials.

[0052] Heat the quartz crucible furnace to 1000-1100°C at a rate of 3-6°C / min. Install a blocking rod and pour the mixed molten raw material powder into the quartz crucible, filling it to 2 / 3-3 / 4 of its volume. Place a heat-resistant steel container filled with water at the crucible furnace outlet. When the furnace temperature reaches 1000°C again, hold it for 0.5-1 hour. Lift the blocking rod to allow the molten glass to flow into the water for water quenching. Collect the quenched glass fragments and dry them for later use.

[0053] (3) Preparation of ZTA ceramic particle corrosion slurry

[0054] The glass cullets obtained in step 2, deionized water, water-soluble hydroxylated acrylic resin, and sodium tripolyphosphate were weighed in a mass ratio of (50-55): (35-40): (5-8): (2-3) and poured into a corundum ball mill with a diameter of 400 mm. Zirconia grinding balls were added at a ball-to-glass ratio of 1.2:1, with 20 mm diameter grinding balls accounting for 40% of the mass and 10 mm diameter grinding balls accounting for 60% of the mass. The ball mill was rotated at 240-260 r / min. After ball milling the raw materials for 10-12 hours, the milled slurry was passed through a 150# sieve and stored in a sealed container to obtain a ZTA ceramic particle etching slurry.

[0055] (4) Chemical thermal corrosion of ZTA ceramic particles

[0056] The ZTA particles treated in step 1 are immersed in the ZTA ceramic particle etching slurry obtained in step 3 for 5-10 minutes, then scooped out with a sieve, dried at room temperature for 24-48 hours, and then dried at 80-100°C for 4-6 hours. The ZTA particles are then spread flat on a ceramic plate and placed in a box furnace, heated to 850-950°C at a rate of 3-6°C / min, kept warm for 1-3 hours, and then cooled with the furnace to obtain ZTA particles after chemical thermal etching treatment.

[0057] (5) Surface cleaning of ZTA particles after chemical thermal corrosion treatment

[0058] Prepare a NaOH solution with a concentration of 4-6 mol / L and heat it in a water bath to 70-80°C. Immerse the ZTA particles obtained in step (4) after the chemical hot etching treatment in the NaOH solution, with the added mass of the ZTA particles not exceeding 20% ​​of the mass of the NaOH solution. After soaking the ZTA particles in the 70-80°C NaOH solution for 4-6 hours, remove them and rinse them with deionized water until neutral. After drying the ZTA particles at room temperature, place them in a 10% HF solution, with the amount not exceeding 50% of the weight of the HF solution. Place the HF solution container soaked with ZTA particles in an ultrasonic cleaner and ultrasonicate at a frequency of 2000-4000 Hz for 1-2 hours at room temperature. Remove the ZTA particles and rinse them with deionized water until neutral. After drying at room temperature, obtain ZTA particles treated with surface thermal chemical etching.

[0059] The present invention will be further explained below:

[0060] (1) Surface pretreatment of ZTA ceramic particles

[0061] ZTA ceramic particles of a certain size are immersed in a cleaning solution mixed with sodium carbonate and O-25 Paringa. The alkaline sodium carbonate solution is effective in cleaning and degreasing, while the O-25 Paringa acts as a surfactant, enhancing the cleaning effectiveness of the sodium carbonate solution. Ultrasonic cleaning ensures the ZTA particles remain immersed in the cleaning solution.

[0062] (2) Preparation of special corrosion glass frit for ZTA ceramic particles

[0063] The composition of the Pyrex glass powder in the special etching glass for ZTA ceramic particles is 78-82.9% silicon dioxide, 11.5-13.6% boron trioxide, 2.0-3.2% aluminum oxide, and 3.6-5.2% sodium oxide. It is the main component of the etching glass and constitutes the main network structure of the etching glass. (Pyrex glass is a borosilicate hard glass used to manufacture experimental instruments, vacuum system components, cookware, and pipes and equipment in the chemical, pharmaceutical, and food industries. "Pyrex" glass was originally a trade name of the American Corning Glass Company. Later, technicians in this field used this name to refer to the borosilicate hard glass with the above composition.) After being melted at above 1000℃, sodium carbonate enters the network structure of the etching glass in the form of sodium oxide, further lowering the softening point of the etching glass. After being melted at above 1000℃, sodium hexafluorosilicate provides F to the etching glass. - And a small amount of SiO2 and Na2O, among which F - When entering the network structure of the corroded glass, it will locally replace O 2-Anion. Because fluoride ion is negative and F element has strong electronegativity, it will greatly destroy the integrity of the network structure of the corroded glass, reduce the softening point and surface tension of the glass, and increase its chemical reaction activity. ZnO is added to the corroded glass because Zn 2+ Its outermost electron structure is 3s 2 3P 6 3d 10 , which has a strong polarizing effect on the surrounding anions, can further reduce the integrity of the corrosion glass network structure and further reduce the softening point of the glass.

[0064] After the weighed raw materials are evenly mixed by ball milling, they are put into a quartz crucible furnace at 1000-1100℃. The raw materials decompose and melt evenly to form molten liquid glass material, which is then quenched with water to obtain corrosion glass material fragments.

[0065] (3) Preparation of ZTA ceramic particle corrosion slurry

[0066] The ZTA ceramic particle etching slurry is obtained by ball-milling etched glass frit fragments, deionized water, water-soluble hydroxylated acrylic resin, and sodium tripolyphosphate in a specific mass ratio. Deionized water serves as the dispersing medium, while the water-soluble hydroxylated acrylic resin acts as a temporary binder. Sodium tripolyphosphate acts as a dispersant, improving the suspension stability of the etched glass frit powder in the water-based etching slurry and facilitating complete wetting and coating of the ZTA particles by the etching slurry in subsequent processes.

[0067] (4) Chemical thermal corrosion of ZTA ceramic particles

[0068] Immerse the cleaned ZTA particles in the ZTA ceramic particle etching slurry, then remove them with a sieve. After drying at room temperature for 24-48 hours, and then drying at 80-100°C for 4-6 hours, the water-soluble hydroxyl acrylic resin in the etching slurry, which serves as a temporary adhesive, solidifies, and a layer of etching glass frit powder is bonded and coated on the surface of the ZTA particles. The ZTA particles are then spread flat on a ceramic plate and placed in a box furnace at a heating rate of 3-6°C / min. When the temperature exceeds 400°C, the hydroxyl acrylic resin begins to carbonize and oxidize. When the temperature exceeds 650°C, the etching glass frit powder begins to soften. Further increasing the temperature to 850-950°C, the etching glass frit powder on the surface of the ZTA particles forms a molten viscous fluid because there is a certain amount of F in the glass frit. -, which reduces the surface tension of the molten glass, allowing for wetting and uniform coating of the ZTA particles. ZTA ceramic particles are a composite material composed of aluminum oxide and zirconium oxide. During the heat preservation process, the corroded glass contains a large amount of Na2O, which provides "free oxygen" to the aluminum oxide on the surface of the ZTA particles, transforming the "aluminum oxide octahedron" on the surface of the ZTA particles into "aluminum oxide tetrahedron", which then melts into the molten corroded glass. In addition, the corroded glass contains a large amount of Zn with a strong polarization effect. 2+ , which polarizes the O 2- This reduces the strength of the Al-O bond and increases the rate of dissolution of the aluminum oxide on the surface of the ZTA ceramic particles into the etchant glass. However, the zirconium oxide in the ZTA ceramic particles, due to its high chemical stability, does not react with the molten etchant glass. Therefore, as the holding time increases, the aluminum oxide-rich areas on the ZTA particle surface gradually dissolve into the molten etchant glass, while the zirconium oxide-rich areas remain largely unchanged, resulting in a rough, uneven surface structure on the ZTA particles.

[0069] (5) Surface cleaning of ZTA particles after chemical thermal corrosion treatment

[0070] The surface of the sintered ZTA particles is covered with a layer of molten corroded glass. - , which replaces part of O in the glass frit network structure 2- This reduces the integrity of the etched glass network and significantly decreases the chemical stability of the etched glass frit. Therefore, the ZTA particles after chemical hot etching are immersed in a NaOH solution. The etched glass frit on the surface of the ZTA particles is corroded and dissolved by the hot NaOH solution, while the ZTA particles do not react with the NaOH solution. The ZTA particles after NaOH soaking are then immersed in a 10% HF solution to further remove the etched glass frit on the ZTA particles, resulting in a clean surface of the thermochemically etched ZTA particles.

[0071] The present application is further described below with reference to specific embodiments.

[0072] Example 1

[0073] This embodiment provides a ZTA ceramic particle surface thermochemical etching process with the following specific steps:

[0074] (1) Surface pretreatment of ZTA ceramic particles

[0075] ZTA ceramic particles of a specific size were immersed in a cleaning solution containing 6wt% sodium carbonate and 2wt% O-25 Peregal. Ultrasonic cleaning was performed at 4000Hz for 20 minutes. The ZTA ceramic particles were removed, rinsed with water until neutral, dried in an 80°C oven, and sealed for storage. This completed the surface cleaning of the ZTA particles.

[0076] (2) Preparation of special corrosion glass frit for ZTA ceramic particles

[0077] The raw material formula (mass percentage wt%) of the special corrosion glass frit for ZTA ceramic particles is:

[0078]

[0079] Pour the weighed raw materials into a 400mm diameter corundum ball mill. Add 10mm diameter corundum balls at a 1:1 ball-to-material ratio. Rotate the mill at 150 rpm. Mill the raw materials for 60 minutes and then remove them to obtain the smelting raw materials.

[0080] Heat the quartz crucible furnace to 1100°C at a rate of 5°C / min. Insert the plugging rod and pour the mixed molten raw material powder into the quartz crucible, filling it to 3 / 4 of its volume. Place a heat-resistant steel container filled with water at the crucible furnace outlet. When the furnace temperature reaches 1000°C again, hold it for half an hour. Lift the plugging rod and allow the molten glass to flow into the water for water quenching. Collect the quenched glass fragments and dry them for later use.

[0081] (3) Preparation of ZTA ceramic particle corrosion slurry

[0082] The glass cullets obtained in step 2, deionized water, water-soluble hydroxylated acrylic resin, and sodium tripolyphosphate were weighed in a mass ratio of 55:35:8:2 and poured into a corundum ball mill with a diameter of 400 mm. Zirconia grinding balls were added at a ball-to-glass ratio of 1.2:1, with 20 mm diameter balls accounting for 40% of the mass and 10 mm diameter balls accounting for 60% of the mass. The ball mill was rotated at 260 rpm. After ball milling the raw materials for 12 hours, the milled slurry was passed through 150°C and stored in a sealed container to obtain a ZTA ceramic particle etching slurry.

[0083] (4) Chemical thermal corrosion process of ZTA ceramic particles

[0084] The ZTA particles treated in step 1 were immersed in the ZTA ceramic particle etching slurry obtained in step 3 for 5 minutes, then scooped out with a sieve, dried at room temperature for 24 hours, and then dried at 80°C for 6 hours. The ZTA particles were then spread flat on a ceramic plate and placed in a box furnace at a rate of 5°C / min to 900°C. The temperature was kept at this temperature for 2 hours, and then cooled with the furnace to obtain ZTA particles after chemical thermal etching treatment.

[0085] (5) Surface cleaning of ZTA particles after chemical thermal corrosion treatment

[0086] Prepare a 6 mol / L NaOH solution and heat it to 80°C in a water bath. Immerse the ZTA particles obtained in step (4) after the chemical hot etching treatment in the NaOH solution, with the added mass of the ZTA particles not exceeding 20% ​​of the mass of the NaOH solution. After soaking the ZTA particles in the 80°C NaOH solution for 6 hours, remove them and rinse them with deionized water until neutral. After drying the ZTA particles at room temperature, place them in a 10% HF solution, with the amount not exceeding 50% of the weight of the HF solution. Place the HF solution container containing the ZTA particles in an ultrasonic cleaner and ultrasonicate at a frequency of 4000 Hz for 1 hour at room temperature. Remove the ZTA particles and rinse them with deionized water until neutral. After drying at room temperature, obtain ZTA particles treated with surface thermal chemical etching.

[0087] from Figure 1 It can be seen that the surface of the uncorroded ZTA particles is relatively smooth. Figure 2 As shown in FIG. 1 , under high magnification, the ZTA particles obtained by etching in Example 1 can be observed to have rough and uneven pits on the surface of the ZTA particles. Figure 3 As shown in the figure, at low magnification, the entire surface of the ZTA particles is rough and uneven with pits.

[0088] Example 2

[0089] This embodiment provides a ZTA ceramic particle surface thermochemical etching process with the following specific steps:

[0090] (1) Surface pretreatment of ZTA ceramic particles

[0091] ZTA ceramic particles of a specific size were immersed in a cleaning solution containing 8% sodium carbonate and 1% O-25 Peregal. Ultrasonic cleaning was performed at 2000 Hz for 20 minutes. The ZTA ceramic particles were removed, rinsed with water until neutral, dried in an 80°C oven, and sealed for storage. This completed the surface cleaning of the ZTA particles.

[0092] (2) Preparation of special corrosion glass frit for ZTA ceramic particles

[0093] The raw material formula (mass percentage wt%) of the special corrosion glass frit for ZTA ceramic particles is:

[0094] Pyrex Glass 75

[0095] Sodium carbonate 10

[0096] Sodium hexafluorosilicate 5

[0097] Zinc oxide 10

[0098] Pour the weighed raw materials into a 400mm diameter corundum ball mill. Add 10mm diameter corundum balls at a ball-to-material ratio of 1:0.5. Rotate the mill at 130 rpm. Mill the raw materials for 30 minutes and then remove them to obtain the smelting raw materials.

[0099] Heat the quartz crucible furnace to 1100°C at a rate of 5°C / min. Insert the plugging rod and pour the mixed molten raw material powder into the quartz crucible, filling it to 3 / 4 of its volume. Place a heat-resistant steel container filled with water at the crucible furnace outlet. When the furnace temperature reaches 1000°C again, hold it for half an hour. Lift the plugging rod and allow the molten glass to flow into the water for water quenching. Collect the quenched glass fragments and dry them for later use.

[0100] (3) Preparation of ZTA ceramic particle corrosion slurry

[0101] The glass cullets obtained in step 2, deionized water, water-soluble hydroxylated acrylic resin, and sodium tripolyphosphate were weighed in a mass ratio of 50:40:5:3 and poured into a corundum ball mill with a diameter of 400 mm. Zirconia grinding balls were added at a ball-to-glass ratio of 1.2:1, with 20 mm diameter balls accounting for 40% of the mass and 10 mm diameter balls accounting for 60% of the mass. The ball mill was rotated at 240 rpm. After ball milling the raw materials for 10 hours, the milled slurry was passed through 150°C and stored in a sealed container to obtain a ZTA ceramic particle etching slurry.

[0102] (4) Chemical thermal corrosion process of ZTA ceramic particles

[0103] The ZTA particles treated in step 1 were immersed in the ZTA ceramic particle etching slurry obtained in step 3 for 5 minutes, then scooped out with a sieve, dried at room temperature for 24 hours, and then dried at 80°C for 6 hours. The ZTA particles were then spread flat on a ceramic plate and placed in a box furnace, heated to 850°C at a rate of 3°C / min, kept warm for 1 hour, and then cooled with the furnace to obtain ZTA particles after chemical thermal etching treatment.

[0104] (5) Surface cleaning of ZTA particles after chemical thermal corrosion treatment

[0105] Prepare a 4 mol / L NaOH solution and heat it to 70°C in a water bath. Immerse the ZTA particles obtained in step (4) after the chemical hot etching treatment in the NaOH solution, with the added mass of the ZTA particles not exceeding 20% ​​of the mass of the NaOH solution. After soaking the ZTA particles in the 80°C NaOH solution for 6 hours, remove them and rinse them with deionized water until neutral. After drying the ZTA particles at room temperature, place them in a 10% HF solution, with the amount not exceeding 50% of the weight of the HF solution. Place the HF solution container containing the ZTA particles in an ultrasonic cleaner and ultrasonicate at a frequency of 2,000 Hz for 1 hour at room temperature. Remove the ZTA particles and rinse them with deionized water until neutral. After drying at room temperature, obtain ZTA particles treated with surface thermal chemical etching.

[0106] Example 3

[0107] This embodiment provides a ZTA ceramic particle surface thermochemical etching process with the following specific steps:

[0108] (1) Surface pretreatment of ZTA ceramic particles

[0109] ZTA ceramic particles of a specific size were immersed in a cleaning solution containing 6wt% sodium carbonate and 2wt% O-25 Peregal. Ultrasonic cleaning was performed at 4000Hz for 20 minutes. The ZTA ceramic particles were removed, rinsed with water until neutral, dried in an 80°C oven, and sealed for storage. This completed the surface cleaning of the ZTA particles.

[0110] (2) Preparation of special corrosion glass frit for ZTA ceramic particles

[0111] The raw material formula (mass percentage wt%) of the special corrosion glass frit for ZTA ceramic particles is:

[0112]

[0113]

[0114] Pour the weighed raw materials into a 400mm diameter corundum ball mill. Add 10mm diameter corundum balls at a ball-to-material ratio of 1:1.5. Rotate the mill at 150 rpm. Mill the raw materials for 60 minutes and then remove them to obtain the smelting raw materials.

[0115] Heat the quartz crucible furnace to 1100°C at a rate of 5°C / min. Install a blocking rod and pour the mixed molten raw material powder into the quartz crucible, filling it to 3 / 4 of its volume. Place a heat-resistant steel container filled with water at the crucible furnace outlet. When the furnace temperature reaches 1100°C again, hold the temperature for 1 hour. Lift the blocking rod to allow the molten glass to flow into the water for quenching. Collect the quenched glass fragments and dry them for later use.

[0116] (3) Preparation of ZTA ceramic particle corrosion slurry

[0117] The glass cullets obtained in step 2, deionized water, water-soluble hydroxylated acrylic resin, and sodium tripolyphosphate were weighed in a mass ratio of 55:35:8:2 and poured into a corundum ball mill with a diameter of 400 mm. Zirconia grinding balls were added at a ball-to-glass ratio of 1.2:1, with 20 mm diameter balls accounting for 40% of the mass and 10 mm diameter balls accounting for 60% of the mass. The ball mill was rotated at 260 rpm. After ball milling the raw materials for 12 hours, the milled slurry was passed through 150°C and stored in a sealed container to obtain a ZTA ceramic particle etching slurry.

[0118] (4) Chemical thermal corrosion process of ZTA ceramic particles

[0119] The ZTA particles treated in step 1 were immersed in the ZTA ceramic particle etching slurry obtained in step 3 for 5 minutes, then scooped out with a sieve, dried at room temperature for 24 hours, and then dried at 80°C for 6 hours. The ZTA particles were then spread flat on a ceramic plate and placed in a box furnace, heated to 950°C at a rate of 6°C / min, kept warm for 3 hours, and then cooled with the furnace to obtain ZTA particles after chemical thermal etching treatment.

[0120] (5) Surface cleaning of ZTA particles after chemical thermal corrosion treatment

[0121] Prepare a 6 mol / L NaOH solution and heat it to 80°C in a water bath. Immerse the ZTA particles obtained in step (4) after the chemical hot etching treatment in the NaOH solution, with the added mass of the ZTA particles not exceeding 20% ​​of the mass of the NaOH solution. After soaking the ZTA particles in the 80°C NaOH solution for 6 hours, remove them and rinse them with deionized water until neutral. After drying the ZTA particles at room temperature, place them in a 10% HF solution, with the amount not exceeding 50% of the weight of the HF solution. Place the HF solution container containing the ZTA particles in an ultrasonic cleaner and ultrasonicate at a frequency of 4000 Hz for 1 hour at room temperature. Remove the ZTA particles and rinse them with deionized water until neutral. After drying at room temperature, obtain ZTA particles treated with surface thermal chemical etching.

[0122] Example 4

[0123] The difference from Example 1 is that the raw material formula (mass percentage wt%) of the special etching glass frit for ZTA ceramic particles is:

[0124] Pyrex Glass 70

[0125] Sodium carbonate 15

[0126] Sodium hexafluorosilicate 5

[0127] Zinc oxide 10

[0128] Example 5

[0129] The difference from Example 1 is that the raw material formula (mass percentage wt%) of the special etching glass frit for ZTA ceramic particles is:

[0130] Pyrex Glass 70

[0131] Sodium carbonate 12

[0132] Sodium hexafluorosilicate 8

[0133] Zinc oxide 10

[0134] Example 6

[0135] The difference from Example 1 is that the raw material formula (mass percentage wt%) of the special etching glass frit for ZTA ceramic particles is:

[0136] Pyrex Glass 70

[0137] Sodium carbonate 10

[0138] Sodium hexafluorosilicate 5

[0139] Zinc oxide 15

[0140] The ZTA particles prepared in Examples 1-6 were placed in a mixer, a certain amount of water glass was added, and after uniform mixing, they were placed in a porous ceramic preform forming mold. After molding under a pressure of 5-10 MPa, they were cured at 80°C for 4 hours. After demolding, a ZTA particle porous ceramic preform of the desired shape was obtained. The preform was then fixed to a designated position of the sand mold according to service requirements, and then a Mn13 ferroalloy melt was poured into the sand mold at a casting temperature of 1500°C. After the casting cooled, a water jet was used to cut a ZTA / Fe-based composite material mechanical test bar with a size of 20×20×150 mm. The three-point flexural strength was then measured on a comprehensive mechanical testing machine. The average flexural strength of the 6 mechanical test bars was 340 MPa. Figure 4It can be seen that after the ZTA particles corroded by the method provided by the present invention are used to prepare the ZTA / Fe-based composite material by the cast infiltration method, the Fe matrix has good wettability on the ZTA particles, and the surface of the ZTA particles in the fracture part is all wrapped by the Fe matrix.

[0141] Commercially available 12-14# ZTA particles were placed in a mixer, a certain amount of water glass was added, and after uniform mixing, the mixture was placed in a porous ceramic preform forming mold. After molding under a pressure of 5-10 MPa, the mixture was cured at 80°C for 4 hours. After demolding, a ZTA particle porous ceramic preform of the desired shape was obtained. The preform was then fixed to a designated position of the casting sand mold according to service requirements. A Mn13 ferroalloy melt was then poured into the sand mold at a casting temperature of 1500°C. After the casting cooled, a water jet was used to cut ZTA / Fe-based composite mechanical test bars with a size of 20×20×150 mm. The three-point flexural strength of the bars was then measured on a comprehensive mechanical testing machine. The average flexural strength of the five mechanical test bars was 280 MPa.

[0142] from Figure 5 It can be seen that after the ordinary commercially available ZTA particles are used to prepare ZTA / Fe-based composites by the casting infiltration method, the Fe matrix has poor wettability on the ZTA particles, and a large amount of the surface of the ZTA particles in the fracture part is not covered by the Fe matrix.

Claims

1. A ZTA particle surface corrosion method, characterized in that: The steps include: The smelted raw materials are ball-milled I, kept at 1000-1100°C for 0.5-1h, and then water-quenched to obtain glass fragments; The glass fragments, water, dispersant and organic binder are mixed and ball milled to obtain a corrosion slurry; Immersing ZTA particles in the etching slurry and then drying to obtain ZTA particles coated with glass powder; The ZTA particles coated with glass powder are subjected to thermal etching at 850-950° C. to obtain ZTA particles with etched surfaces; The smelting raw materials include 70-75 wt% of Pyrex glass, 10-15 wt% of sodium carbonate, 5-8 wt% of sodium hexafluorosilicate and 10-15 wt% of zinc oxide.

2. The ZTA particle surface etching method according to claim 1, wherein: The ball-to-material ratio of the ball mill I is 1:0.5-1.5; The grinding balls used in the ball mill I include corundum grinding balls; The rotation speed of the ball mill I is 130-150 r / min; The time of ball milling I is 30-60 min.

3. The ZTA particle surface etching method according to claim 1, wherein: The organic binder includes a water-soluble hydroxy acrylic resin; The dispersant includes sodium tripolyphosphate; The weight ratio of the glass cullets, water, the organic binder and the sodium tripolyphosphate dispersant is (50-55): (35-40): (5-8): (2-3).

4. The ZTA particle surface etching method according to claim 1, wherein: The ball-to-material ratio of the ball mill II is 1.2:1; The grinding balls used in the ball mill II include zirconium oxide grinding balls; The zirconia grinding balls include 40 wt% of zirconia grinding balls with a diameter of 20 mm and 60 wt% of zirconia grinding balls with a diameter of 10 mm; The speed of the ball mill II is 240-260 r / min; The time of ball milling II is 10-12 hours.

5. The ZTA particle surface etching method according to claim 1, wherein: The heating rate of the thermal corrosion is 3-6°C / min; The thermal corrosion time is 1-3 hours.

6. The ZTA particle surface etching method according to claim 1, wherein: The method also includes the steps of soaking the ZTA ceramic particles in a cleaning solution including sodium carbonate and O-25 type peregrine for ultrasonic cleaning, rinsing with water until neutrality, and drying.

7. The ZTA particle surface etching method according to claim 6, wherein: The concentration of sodium carbonate in the cleaning solution is 6-8wt%; The concentration of O-25 type peregal in the cleaning solution is 1-2wt%; The frequency used in the ultrasonic cleaning is 2000-4000 Hz.

8. The ZTA particle surface etching method according to claim 1, wherein: The method further includes the steps of cleaning the thermally corroded ZTA particles with a strong alkaline solution and then cleaning the particles in an HF solution under ultrasonic conditions.

9. The ZTA particle surface etching method according to claim 8, wherein: The strong alkaline solution includes NaOH solution or KOH solution; The concentration of the strong alkaline solution is 4-6 mol / L; The cleaning temperature of the strong alkaline solution is 70-80°C; The strong alkaline solution cleaning time is 4-6 hours in the early years; The mass of the strong alkaline solution added for cleaning the thermally corroded ZTA particles does not exceed 20% of the mass of the strong alkaline solution.

10. The ZTA particle surface etching method according to claim 8, wherein: The method comprises the step of ultrasonicating in a 10% HF solution at a frequency of 2000-4000 Hz for 1-2 hours.

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