A nano-ceramic abrasive material and a method of making the same

Abstract

The application relates to the field of nanomaterials, in particular to a kind of nano ceramic grinding material and a preparation method thereof.The preparation method comprises the following steps: step 1, pickling nano molybdenum carbide powder; heat treating chromium-plated carbon nanotubes; step 2, weighing nano molybdenum carbide powder and chromium-plated carbon nanotubes, then adding reinforcing agent and inhibitor, and ball milling; step 3, configuring peroxovanadic acid solution; step 4, adding the ball milling agent into the peroxovanadic acid solution, stirring, filtering, drying, and heat treating under temperature rising; and step 5, pre-pressing treatment, then sintering, to obtain the nano ceramic grinding material.The nano ceramic grinding material prepared by the application has high hardness, high toughness and high temperature resistance, and is suitable for nuclear energy or aerospace fields with high requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of nanomaterials, and particularly relates to a nanoceramic grinding material and a preparation method thereof. BACKGROUND

[0002] The grinding material is mainly used for polishing materials, and can be used for polishing glass, metal, leather, semiconductor, plastic, gem, jade, stainless steel, and the like. The nanoceramic grinding material is a new type of grinding material obtained by special crystal induction gelation and sintering, and has the advantages of high hardness, good self-sharpening, high machining precision, and low heat generation rate.

[0003] At present, the traditional grinding material is generally alumina, zirconia, diamond, silicon oxide, cerium oxide, titanium oxide, silicon nitride, or the like. However, in actual application, the existing grinding material particles have defects such as small particle size, large surface activity, strong interaction between particles, and easy agglomeration of the dispersed nanoparticles, which affect the grinding performance. In addition, the traditional abrasive has large brittleness, and the cutting edge is easy to break in grinding, has poor toughness, and has high wear, so that the service life of the abrasive is relatively short.

[0004] In summary, the traditional grinding material (such as alumina, silicon carbide, diamond, etc.) has the following problems in the field of precision machining: (1) large particle size (micron level): leading to high surface roughness (Ra) of the machined surface, which is difficult to meet the needs of high-precision optics and semiconductor devices; (2) contradiction between hardness and toughness: high-hardness materials (such as diamond) are easy to break, while tough materials (such as resin bond) have insufficient wear resistance; (3) poor thermal stability: local high temperature during high-speed grinding easily leads to failure of the binder or oxidation of the particles. Therefore, it is particularly important to develop a grinding material with good hardness and toughness and good thermal stability. SUMMARY

[0005] In view of the problems in the prior art, the purpose of the present application is to provide a nanoceramic grinding material and a preparation method thereof.

[0006] The purpose of the present application is achieved by adopting the following technical solutions:

[0007] In a first aspect, the present application provides a preparation method of a nanoceramic grinding material, comprising the following steps:

[0008] Step 1: acid washing and drying nanometer molybdenum carbide powder, and waiting for use; heat treating chromium-plated carbon nanotubes, and waiting for use;

[0009] Step 2: weighing the nanometer molybdenum carbide powder and the chromium-plated carbon nanotubes treated in step 1, mixing them in anhydrous ethanol, adding a reinforcing agent and an inhibitor, and performing ball milling in a planetary ball mill. After the ball milling is completed, a first mixture is obtained;

[0010] Step 3, weigh vanadium pentoxide and add into hydrogen peroxide solution, after stirring well, adjust pH to 2-3, to obtain peroxovanadic acid solution;

[0011] Step 4, add the first mixture into peroxovanadic acid solution, after stirring and dispersing, filter, dry, and heat treatment, to obtain the second mixture;

[0012] Step 5, load the second mixture into graphite mold, pre-press, then sinter in a spark plasma sintering furnace, after quenching, to obtain nano ceramic abrasive material.

[0013] Preferably, in the step 1, the acid pickling is to add nano molybdenum carbide powder into hydrofluoric acid solution, and ultrasonic treatment for 20-30 min.

[0014] Preferably, the ratio of nano molybdenum carbide and hydrofluoric acid solution is 1g:3-10mL.

[0015] Preferably, in the step 1, the heat treatment is to heat the chromium-plated carbon nanotube to 300℃ under rare gas protection, and heat treatment for 1-2h.

[0016] Preferably, in the step 1, the preparation process of the chromium-plated carbon nanotube comprises:

[0017] S1, purification treatment: weigh carbon nanotube and add into 3mol / L nitric acid solution, stir at 55-65℃ for 12-24h, filter and wash to neutral, then add into hydrofluoric acid solution, stir at room temperature for 10-20h, filter and wash to neutral, and vacuum dry to obtain purified carbon nanotube;

[0018] S2, activation sensitization treatment: add 30-40mL 37wt% hydrochloric acid, 0.6-1.2g dichloropalladium, and 18-25g stannous chloride into 1L deionized water to configure into activation sensitization solution; add the purified carbon nanotube into the activation sensitization solution, ultrasonic treatment for 20-50min, filter and wash to neutral, and vacuum dry to obtain activated and sensitized carbon nanotube;

[0019] S3, chromium plating treatment: configure plating solution: 150-210g chromium chloride hexahydrate, 120-140g sodium hypophosphite, 40-60g sodium oxalate, 60-90g urea, 10-20g formic acid, 90-120g ammonium bromide, 0.3-0.6g hexadecyl dimethyl bromide amine, and 1L deionized water; add 8-18g activated and sensitized carbon nanotube into 1L plating solution, ultrasonic treatment, heat to 70-80℃ and stir for 20-50min, then filter and wash to neutral, and vacuum dry to obtain chromium-plated carbon nanotube.

[0020] Preferably, the inhibitor in step 2 is aluminum oxide powder with a particle size of 10-20 nm.

[0021] Preferably, the reinforcing agent in step 2 is yttria-stabilized zirconia, specifically tetragonal zirconia powder containing 3wt% yttria with a particle size of 200-300 nm.

[0022] Preferably, in step 2, the mass ratio of nano-molybdenum carbide, chromium-plated carbon nanotubes, reinforcing agent and inhibitor is 8-9:1-1.5:5-7:2-5.

[0023] Preferably, in step 2, a rare gas is used as a protective gas during ball milling, ZrO2 grinding balls with a diameter of 0.5-2 mm are selected for ball milling, the ball-to-material ratio is 4-6:1, the ball milling speed is 300-500 r / min, and the ball milling time is 4-8 h.

[0024] Preferably, in step 3, the ratio of vanadium pentoxide and hydrogen peroxide solution is (0.7-0.9) g:(10-15) mL, and the mass fraction of hydrogen peroxide solution is 2%-4%.

[0025] Preferably, in step 4, the ratio of the first mixture and peroxovanadic acid solution is 1 g:(10-15) mL.

[0026] Preferably, the temperature rising heat treatment in step 4 specifically includes: first, heating to 100℃ at a rate of 3-5℃ / min and maintaining for 20-30 min, then heating to 650℃ at a rate of 20-30℃ / min and maintaining for 10-20 min, and then cooling with the furnace.

[0027] Preferably, the sintering in step 5 specifically includes: first, heating to 600-750℃ at a rate of 100℃ / min to rearrange the particles using V2O5 melt; then heating to 1400-1450℃ at a rate of 50℃ / min, and then maintaining for 5-10 min to control the grain size.

[0028] Preferably, the rare gas is one of helium, neon, argon, krypton and xenon.

[0029] Preferably, in step 5, the pre-pressing treatment parameters are: pre-pressing for 5-10 min under a pressure of 10-20 MPa.

[0030] Preferably, in step 5, the quenching is spray cooling with a rare gas (helium is best, the cooling rate is 8 times that of argon).

[0031] In a second aspect, the present application provides a nano-ceramic abrasive material prepared by the above preparation method.

[0032] The beneficial effects of the present application are:

[0033] 1、The present application prepares a kind of nanoceramic abrasive material, MoC is used as abrasive material matrix, the toughening effect of chrome-plated carbon nanotube is solved the problem that traditional ceramic toughness and hardness cannot be compatible, and yttria-stabilized zirconia and nanoscale alumina are introduced as additive to realize multistage synergistic strengthening.The nanoceramic rigid material has high hardness, high toughness and high temperature resistance, and is suitable for nuclear energy or aerospace field with higher demand.

[0034] 2、The nanoceramic abrasive material prepared in the present application selects MoC as abrasive material matrix, MoC material not only has high hardness but also good high-temperature stability;Chrome-plated carbon nanotube is used as modifier, chrome-plated carbon nanotube is plated with chrome on the surface of carbon nanotube, on the one hand, the bridging toughening mechanism is used to enhance the fracture toughness of carbon nanotube, on the other hand, Cr coating and MoC can generate Cr3C2 interface layer to enhance the interfacial bonding force with MoC;Yttria-stabilized zirconia is used as reinforcing agent, which can play phase change toughening effect to enhance the toughness of ceramic;Nanoscale alumina is used as inhibitor, which can inhibit abnormal grain growth and maintain the nanostructure of abrasive material.

[0035] 3、In the heat treatment process of the present application, the mixed material is treated with peroxovanadic acid solution, first heated to 100 DEG C, and then rapidly heated to the melting point (650 DEG C) of V2O5, V2O5 can form a low-viscosity melt to rapidly wet the surface of the particles, and at this temperature, V2O5 can combine with MoC to generate crystalline molybdate (MoV2O8) in situ to fill the pores of the particles, thereby improving the density.

[0036] 4、In the sintering process of the present application, rapid heating can avoid grain coarsening caused by long-term medium-temperature residence, at 600-750 DEG C, crystalline molybdate (MoV2O8) will decompose into amorphous V2O5 again, forming a nanoscale lubricating film on the surface of the particles, which can not only realize particle rearrangement but also prevent particle agglomeration, so that the grain size is smaller;Then rapidly heated to 1450 DEG C, which can promote the densification of MoC, and Cr coating and MoC can also react to generate Cr3C2 interface layer, thereby improving the CNTs bonding strength.

[0037] 5、In the present application, the sintering holding time is 5-10 min, which is much lower than the sintering holding time of the traditional process, not only speeding up the production rate, but also obtaining smaller grains (about 100 nm) and better density. In addition, after high-temperature sintering, a spray quenching method is used for cooling, which can not only inhibit the grain boundary migration of MoC, but also greatly avoid the oxidation of MoC in the slow cooling process, and also reduce the stress change difference between Cr-CNTs and MoC matrix, greatly prolonging the fatigue life. DETAILED DESCRIPTION

[0038] The technical solutions of the present application are described below through specific examples. It should be understood that the one or more method steps mentioned in the present application do not exclude other method steps before and after the combination steps or other method steps inserted between the explicitly mentioned steps; it should also be understood that these examples are only used to illustrate the present application and not to limit the scope of the present application. Moreover, unless otherwise stated, the numbering of each method step is only a convenient tool to identify each method step, and is not a limitation on the arrangement order of each method step or a limitation on the scope of the present application that can be implemented. Changes or adjustments of the relative relationship without substantial changes in technical content are also considered as the scope of the present application that can be implemented.

[0039] In order to better understand the above technical solutions, the exemplary embodiments of the present application are described in more detail below. Although exemplary embodiments of the present application are shown, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0040] The present application is further described below in conjunction with the following examples.

[0041] Example 1

[0042] A method for preparing a nano-ceramic abrasive material, comprising the following steps:

[0043] Step 1: 1 g of nano-molybdenum carbide (MoC) is added to 6 mL of 10 wt% hydrofluoric acid solution, ultrasonically treated for 25 min, and dried under reduced pressure for use; chromium-coated carbon nanotubes (Cr-CNTs) are heated to 300℃ under helium protection and heat treated for 1 h, and then cooled for use;

[0044] Step 2, 8.5 g of nano-carbonized molybdenum powder and 1.2 g of chromium-plated carbon nanotubes are weighed and mixed in 20 mL of anhydrous ethanol, 6 g of tetragonal zirconium oxide powder containing 3 wt% yttrium oxide (particle size 200-300 nm) is added as a reinforcing agent, and 4 g of aluminum oxide powder (particle size 10-20 nm) is added as an inhibitor, and ball milling is performed in a planetary ball mill with ZrO2 balls of 1 mm in diameter, helium gas as a protective gas, a ball-to-material ratio of 5:1, a ball milling speed of 500 r / min, and a ball milling time of 6 h. After ball milling, drying is performed to obtain a first mixture;

[0045] Step 3, 0.8 g of vanadium pentoxide is added to 10 mL of 3 wt% hydrogen peroxide solution, and after being stirred uniformly, hydrochloric acid is added to adjust the pH to 2-3 to obtain a peroxovanadic acid solution;

[0046] Step 4, 1 g of the first mixture is added to 10 mL of the peroxovanadic acid solution, stirred and dispersed for 30 min, then filtered and dried, and heat treated in a muffle furnace by first increasing the temperature to 100°C at a rate of 4°C / min and maintaining the temperature for 25 min, then increasing the temperature to 650°C at a rate of 25°C / min and maintaining the temperature for 15 min, and then cooling in the furnace to obtain a second mixture;

[0047] Step 5, the second mixture is loaded into a graphite mold, pre-pressed at a pressure of 15 MPa for 10 min, and then sintered in a spark plasma sintering furnace by first increasing the temperature to 700°C at a rate of 100°C / min, then increasing the temperature to 1450°C at a rate of 50°C / min, and then maintaining the temperature for 10 min, and then cooling by helium gas spraying at a cooling rate of 200-300°C / s to obtain a nano-ceramic grinding material.

[0048] In step 1, the preparation process of the chromium-plated carbon nanotubes includes:

[0049] S1, purification treatment: 100 g of carbon nanotubes is added to 1 L of 3 mol / L nitric acid solution, stirred at 60°C for 18 h, filtered and washed to neutral, then added to a hydrofluoric acid solution, stirred at room temperature for 15 h, filtered and washed to neutral, and vacuum dried to obtain purified carbon nanotubes;

[0050] S2, activation and sensitization treatment: 35 mL of 37 wt% hydrochloric acid, 0.9 g of dichloropalladium, and 21 g of stannous chloride are added to 1 L of deionized water to prepare an activation and sensitization solution; the purified carbon nanotubes are added to the activation and sensitization solution, ultrasonically treated for 30 min, filtered and washed to neutral, and vacuum dried to obtain activated and sensitized carbon nanotubes;

[0051] S3, chromium plating treatment: configure plating solution: 180 g of chromium chloride hexahydrate (CrCl3·6H2O), 130 g of sodium hypophosphite (NaH2PO2), 50 g of sodium oxalate, 70 g of urea, 15 g of formic acid, 100 g of ammonium bromide, 0.5 g of cetyl dimethyl bromide amine and 1 L of deionized water, 13 g of activated and sensitized carbon nanotubes are added into 1 L of plating solution, ultrasonic is uniformly added, and then the temperature is raised to 80°C and stirred for 30 min, then filtered and washed to neutral, vacuum dried, and chromium-plated carbon nanotubes are obtained.

[0052] Example 2

[0053] A method for preparing a nanoceramic abrasive material, comprising the following steps:

[0054] Step 1, 1 g of nanometer molybdenum carbide (MoC) is added to 5 mL of 10 wt% hydrofluoric acid solution, ultrasonic treatment is performed for 20 min, and then it is dried under reduced pressure and ready for use; the chromium-plated carbon nanotubes (Cr-CNTs) are heated to 300°C under helium protection and heat treated for 1 h, and then cooled and ready for use;

[0055] Step 2, 8 g of nanometer molybdenum carbide powder and 1 g of chromium-plated carbon nanotubes are mixed in 15 mL of anhydrous ethanol, 5 g of tetragonal zirconia powder containing 3 wt% yttrium oxide (particle size of 200-300 nm) is added as a reinforcing agent, and 2 g of aluminum oxide powder (particle size of 10-20 nm) is added as an inhibitor, and then the mixture is ball milled in a planetary ball mill, ZrO2 balls with a diameter of 1 mm are used, helium is used as the protective gas, the ball-to-material ratio is 4:1, the ball milling speed is 300 r / min, and the ball milling time is 4 h; after ball milling, the mixture is dried to obtain a first mixture;

[0056] Step 3, 0.7 g of vanadium pentoxide is added to 10 mL of 2 wt% hydrogen peroxide solution, and then the mixture is stirred uniformly, and the pH is adjusted to 2-3 with hydrochloric acid to obtain a peroxovanadic acid solution;

[0057] Step 4, 1 g of the first mixture is added to 10 mL of the peroxovanadic acid solution, and then the mixture is stirred and dispersed for 20 min, and then filtered and dried, and then heated and treated in a muffle furnace, the temperature is raised to 100°C at a rate of 3°C / min and maintained for 20 min, and then the temperature is raised to 650°C at a rate of 20°C / min and maintained for 10 min, and then the furnace is cooled to obtain a second mixture;

[0058] Step 5, the second mixture is filled into a graphite mold, pre-pressed at a pressure of 10 MPa for 5 min, and then sintered in a spark plasma sintering furnace, first heated to 600℃ at a rate of 100℃ / min, then heated to 1400℃ at a rate of 50℃ / min, and then kept for 5 min, and then cooled by helium gas spraying at a cooling rate of 200-300℃ / s, to obtain the nano ceramic grinding material.

[0059] In step 1, the preparation process of the chromium-plated carbon nanotubes includes:

[0060] S1, purification treatment: 100 g of carbon nanotubes are added to 2 L of 3 mol / L nitric acid solution, stirred at 55℃ for 12 h, filtered and washed to neutral, then added to a hydrofluoric acid solution, stirred at room temperature for 10 h, filtered and washed to neutral, and vacuum dried to obtain purified carbon nanotubes;

[0061] S2, activation sensitization treatment: 30 mL of 37wt% hydrochloric acid, 0.6 g of dichloropalladium, and 18 g of stannous chloride are added to 1 L of deionized water to prepare an activation sensitization solution; the purified carbon nanotubes are added to the activation sensitization solution, ultrasonically treated for 20 min, filtered and washed to neutral, and vacuum dried to obtain activated and sensitized carbon nanotubes;

[0062] S3, chromium plating treatment: a plating solution is prepared by mixing 150 g of chromium chloride hexahydrate (CrCl3·6H2O), 120 g of sodium hypophosphite (NaH2PO2), 40 g of sodium oxalate, 60 g of urea, 10 g of formic acid, 90 g of ammonium bromide, 0.3 g of hexadecyl dimethyl ammonium bromide, and 1 L of deionized water; 8 g of activated and sensitized carbon nanotubes are added to 1 L of the plating solution, ultrasonically mixed, heated to 70℃ and stirred for 20 min, then filtered and washed to neutral, and vacuum dried to obtain chromium-plated carbon nanotubes.

[0063] Example 3

[0064] A method for preparing a nano ceramic grinding material, comprising the following steps:

[0065] Step 1, 1 g of nano molybdenum carbide (MoC) is added to 10 mL of 10wt% hydrofluoric acid solution, ultrasonically treated for 30 min, and dried under reduced pressure for use; chromium-plated carbon nanotubes (Cr-CNTs) are heated to 300℃ under helium protection for 2 h of heat treatment, and then cooled for use;

[0066] Step 2, 9 g of nano-carbonized molybdenum powder and 1.5 g of chromium-plated carbon nanotubes are weighed and mixed in 25 mL of anhydrous ethanol, 7 g of tetragonal zirconium oxide powder containing 3 wt% yttrium oxide (particle size 200-300 nm) is added as a reinforcing agent, and 5 g of aluminum oxide powder (particle size 10-20 nm) is added as an inhibitor, and ball milling is performed in a planetary ball mill with ZrO2 balls of 1 mm in diameter, helium gas as a protective gas, a ball-to-material ratio of 6:1, a ball milling speed of 500 r / min, and a ball milling time of 8 h. After ball milling, drying is performed to obtain a first mixture;

[0067] Step 3, 0.9 g of vanadium pentoxide is added to 15 mL of 4 wt% hydrogen peroxide solution, and after being stirred uniformly, hydrochloric acid is added to adjust the pH to 2-3 to obtain a peroxovanadic acid solution;

[0068] Step 4, 1 g of the first mixture is added to 15 mL of the peroxovanadic acid solution, stirred and dispersed for 40 min, then filtered and dried, and heat treated in a muffle furnace by first increasing the temperature to 100°C at a rate of 5°C / min and maintaining the temperature for 30 min, then increasing the temperature to 650°C at a rate of 30°C / min and maintaining the temperature for 20 min, and then cooling in the furnace to obtain a second mixture;

[0069] Step 5, the second mixture is loaded into a graphite mold, pre-pressed at a pressure of 20 MPa for 5-10 min, and then sintered in a spark plasma sintering furnace by first increasing the temperature to 750°C at a rate of 100°C / min, then increasing the temperature to 1450°C at a rate of 50°C / min, and then maintaining the temperature for 10 min, and then cooling at a rate of 200-300°C / s with helium gas spraying to obtain a nano-ceramic grinding material.

[0070] In step 1, the preparation process of the chromium-plated carbon nanotubes includes:

[0071] S1, purification treatment: 100 g of carbon nanotubes is added to 500 mL of 3 mol / L nitric acid solution, stirred at 65°C for 24 h, filtered and washed to neutral, then added to a hydrofluoric acid solution, stirred at room temperature for 20 h, filtered and washed to neutral, and vacuum dried to obtain purified carbon nanotubes;

[0072] S2, activation and sensitization treatment: 40 mL of 37 wt% hydrochloric acid, 1.2 g of dichloropalladium, and 25 g of stannous chloride are added to 1 L of deionized water to prepare an activation and sensitization solution; the purified carbon nanotubes are added to the activation and sensitization solution, ultrasonically treated for 50 min, filtered and washed to neutral, and vacuum dried to obtain activated and sensitized carbon nanotubes;

[0073] S3, chrome plating treatment: configure plating solution: 210 g of chromium chloride hexahydrate (CrCl3·6H2O), 140 g of sodium hypophosphite (NaH2PO2), 60 g of sodium oxalate, 90 g of urea, 20 g of formic acid, 120 g of ammonium bromide, 0.6 g of cetyl dimethyl bromide amine and 1 L of deionized water, 18 g of activated and sensitized carbon nanotubes are added into 1 L of plating solution, after ultrasonic uniformity, the temperature is raised to 80℃ and stirred for 50 min, then filtered and washed to neutral, vacuum dried, and chrome-plated carbon nanotubes are obtained.

[0074] Comparative Example 1

[0075] A method for preparing a nano-ceramic abrasive material, which is different from Example 1 in that the chrome-plated carbon nanotubes (Cr-CNTs) are replaced by traditional carbon nanotubes (CNTs) without chrome plating in the preparation process of the nano-ceramic abrasive material, and other components and preparation parameters remain unchanged.

[0076] Comparative Example 2

[0077] A method for preparing a nano-ceramic abrasive material, which is different from Example 1 in that the mixed material is not treated with vanadyl peroxide solution in the preparation process of the nano-ceramic abrasive material, and is directly sintered, i.e. steps 3 and 4 in Example 1 are omitted, and other components and preparation parameters remain unchanged.

[0078] Comparative Example 3

[0079] A method for preparing a nano-ceramic abrasive material, which is different from Example 1 in that the sintering process in step 5 is different. In step 5, the sintering parameters are adjusted to sintering at 1700℃ in a high-temperature graphite furnace for 60 min, and the cooling is furnace cooling, and other components and preparation parameters remain unchanged.

[0080] Performance detection:

[0081] The grain size, hardness, toughness, density, wear resistance and high-temperature stability of the nano-ceramic abrasive materials prepared in Example 1 and Comparative Examples 1-3 are detected.

[0082] Detection method or standard reference:

[0083] (1) Grain size: refer to GB / T 23413-2009 "Nano-material grain size and micro-strain determination";

[0084] (2) Vickers hardness: refer to ISO 6507-1:2018 "Metal material Vickers hardness test", parameters: load 500 g, holding time 15 s;

[0085] (3) Fracture toughness: reference ASTM E399-2020 "Standard Test Method for Linear- Elastic Plane-Strain Fracture Toughness of Metallic Materials" for single edge notched beam (SENB) method;

[0086] (4) Density: reference GB / T 25995-2010 "Fine Ceramic Density and Apparent Porosity Test Method", take the average value;

[0087] (5) Wear rate: reference GB / T 12444-2006 "Metallic Materials Wear Test Method Ring-Block Sliding Wear Test" for ring-block wear test, parameters: load 50N, rotation speed 200rpm, counter abrasive GCr15 steel;

[0088] (6) High temperature hardness retention rate: under argon protection, heat to 1000℃ for 30min, then use high temperature dynamic in-situ nano indentation instrument to detect, take the average value.

[0089] The results of the detection are shown in the following table:

[0090] Table 1 Performance comparison of different nano ceramic abrasive materials

[0091] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Grain size (nm) 90±10 125±15 360±40 850±100 Vickers hardness (GPa) 36.7 32.1 29.2 25.4 fracture toughness (MPa.m 1 / 2 ) 8.9 6.3 5.9 4.3 Density ≥99.5% 96.2% 92.4% 97.8% wear rate (mm 3 (N-m) ) / (N-m) 1.2 x 10 -7 ]]> 3.3 x 10 -7 ]] 6.8 x 10 -7 ]] 9.5 x 10 -7 <!-- 6 -->]]> High temperature (1000 °C, 30 min, Ar2) hardness retention 82.4% 69.1% 61.8% 46.2%

[0092] From the above detection results, it can be seen that the nano ceramic abrasive material prepared in Example 1 of the present application can balance hardness, wear resistance and hardness, and at the same time, the density and high temperature stability also perform excellently, in addition, it also has smaller and stable grain size, compared with other comparative examples, it has obvious advantages, and is more suitable for nuclear energy or aerospace field with higher demand.

[0093] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in the present specification.

[0094] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A method for producing a nanoceramic abrasive material, characterized by, It comprises the following steps: Step 1, dry the acid-washed nano-molybdenum carbide powder and reserve it; heat-treat the chromium-plated carbon nanotubes and reserve them; Step 2, weigh the nano-molybdenum carbide powder and the chromium-plated carbon nanotubes treated in Step 1, mix them in anhydrous ethanol, add a reinforcing agent and an inhibitor, and perform ball milling in a planetary ball mill; after the ball milling is completed, a first mixture is obtained; Step 3, weigh vanadium pentoxide and add it to a hydrogen peroxide solution; after the vanadium pentoxide is fully stirred and evenly distributed, adjust the pH to 2-3 to obtain a vanadyl peroxide solution; Step 4, add the first mixture to the vanadyl peroxide solution, stir and disperse, filter, dry, and heat-treat at an elevated temperature to obtain a second mixture; Step 5, load the second mixture into a graphite mold, perform pre-pressing treatment, then place it in a spark plasma sintering furnace for sintering, and after quenching, a nano-ceramic abrasive material is obtained.

2. The method of claim 1, wherein the nano-ceramic abrasive material is prepared by the steps of: In Step 1, the acid-washing is performed by adding the nano-molybdenum carbide powder to a hydrofluoric acid solution and ultrasonic treatment for 20-30 min; the ratio of the nano-molybdenum carbide powder to the hydrofluoric acid solution is 1g:(3-10)mL. ​ 3. The method for preparing a nano-ceramic abrasive material according to claim 1, characterized in that, In Step 1, the heat-treatment is performed by heating the chromium-plated carbon nanotubes to 300℃ under rare gas protection for 1-2 h.

4. The method for preparing a nano-ceramic abrasive material according to claim 1, characterized in that, In Step 1, the preparation process of the chromium-plated carbon nanotubes comprises: sequentially performing purification treatment, activation sensitization treatment, and chromium plating treatment on the carbon nanotubes; wherein the plating solution composition comprises: 150-210g of chromium chloride hexahydrate, 120-140g of sodium hypophosphite, 40-60g of sodium oxalate, 60-90g of urea, 10-20g of formic acid, 90-120g of ammonium bromide, 0.3-0.6g of hexadecyl dimethyl ammonium bromide, and 1L of deionized water.

5. The method for preparing a nano-ceramic abrasive material according to claim 1, characterized in that, In Step 2, the inhibitor is aluminum oxide powder with a particle size of 10-20nm; the reinforcing agent is yttria-stabilized zirconia, specifically tetragonal zirconia powder containing 3wt% yttria with a particle size of 200-300nm.

6. The method of claim 1, wherein the nanoceramic abrasive material is prepared by the steps of: In Step 2, the mass ratio of the nano-molybdenum carbide, the chromium-plated carbon nanotubes, the reinforcing agent, and the inhibitor is 8-9:1-1.5:5-7:2-5.

7. The method for preparing a nano-ceramic abrasive material according to claim 1, characterized in that, In Step 3, the ratio of vanadium pentoxide to hydrogen peroxide solution is (0.7-0.9)g:(10-15)mL; the mass fraction of the hydrogen peroxide solution is 2%-4%; in Step 4, the ratio of the first mixture to the vanadyl peroxide solution is 1g:(10-15)mL.

8. The method for preparing a nano-ceramic abrasive material according to claim 1, characterized in that, The elevated temperature heat-treatment in Step 4 specifically comprises: first, heating at a rate of 3-5℃ / min to 100℃ for 20-30min in a muffle furnace, then heating at a rate of 20-30℃ / min to 650℃ for 10-20min, and then cooling with the furnace.

9. The method for preparing a nano-ceramic abrasive material according to claim 1, characterized in that, The sintering in step 5 specifically comprises: first, heating at a speed of 100℃ / min to 600-750℃, then heating at a speed of 50℃ / min to 1400-1450℃, and then holding for 5-10min; the pre-pressing treatment parameters in step 5: pre-pressing treatment under a pressure of 10-20MPa for 5-10min; the quenching is through rare gas spray cooling, and the cooling speed is controlled at 200-300℃ / s.

10. A nanoceramic abrasive material, characterized in that, The preparation method of claim 1 is adopted to prepare.