Zirconium boride-based composite ceramic electrode for electric arc furnace and preparation method thereof

Abstract

The present invention relates to a zirconium boride-based composite ceramic electrode for an electric arc furnace and a preparation method thereof. The technical solution is as follows: zirconium boride powder, zirconium carbide powder, silicon powder, and tungsten powder are first mixed, ball-milled, and dried to obtain a composite powder. The composite powder is then compacted and cold isostatically pressed to obtain a ceramic body. The ceramic body is placed in a vacuum induction furnace and subjected to vacuum induction sintering to produce a zirconium boride-based composite ceramic electrode for an electric arc furnace. The vacuum induction sintering process is as follows: first, open the circulating water valve, then turn on the power supply of the induction furnace. Under vacuum conditions, heat the electrode to 800-900°C, then to 1500-1600°C, maintain the temperature, turn off the power supply of the induction furnace, and then close the circulating water valve. The zirconium boride-based composite ceramic electrode for an electric arc furnace prepared by the present invention has good wear resistance, excellent fracture toughness, high electrical conductivity, and excellent thermal conductivity.

Description

Technical Field

[0001] The present invention belongs to the technical field of zirconium boride-based composite ceramic electrodes, and specifically relates to a zirconium boride-based composite ceramic electrode for an electric arc furnace and a preparation method thereof. Background Art

[0002] Electric arc furnace steelmaking is a steelmaking process that utilizes the high temperatures generated by an electric arc to recover scrap steel and melt raw materials. Compared to existing blast furnace steelmaking, electric arc furnaces offer advantages such as lower energy consumption, less environmental pollution, and greater flexibility, making them an increasingly important part of steel production.

[0003] In current research on electric arc furnace electrode materials, graphite electrodes are widely used due to their excellent electrical conductivity and chemical stability. However, graphite electrodes suffer from poor toughness and are prone to oxidation in high-temperature and high-pressure environments. Their low hardness and wear also shorten their service life. Therefore, the search for electrode materials with even better performance has become a research priority. Zirconium boride-based composite ceramics, due to their excellent thermal stability, high hardness, high electrical conductivity, and excellent thermal conductivity, are attracting the attention of those skilled in the art as promising alternatives to graphite electrodes.

[0004] The patented technology of "A graphite electrode for electric arc furnace (CN201821619781.2)" improves the overall cooling effect of the graphite electrode and extends the service life of the graphite electrode. However, the graphite electrode has a low hardness, resulting in high wear and consumption.

[0005] The patented technology of "A graphite electrode for electric arc furnace (CN202021539191.6)" provides a simple and low-cost preparation process, but the fracture toughness of the prepared electrode is low.

[0006] The patented technology "A graphite electrode for electric arc furnaces (CN202021148051.6)" introduces inert gas through the ventilation channel to cool the graphite electrode body to reduce surface oxidation of the graphite electrode. The gas effectively forms gas turbulence inside the ventilation channel. Although the heat exchange efficiency is high and the cooling effect is good, the conductivity of the prepared graphite electrode is low.

[0007] A literature (Yang BL, Kuang CL, Liu ZL, et al. Effect of nano-graphite on mechanical properties and oxidation resistance of ZrB2-SiC-graphite electrodeceramics[J]. Journal of Iron and Steel Research International, 2024, 31(6): 1502-1513.) proposed the introduction of nano-graphite into zirconium boride ceramic electrodes for electric arc furnaces. Although the fracture toughness is improved to a certain extent, excessive graphite will lead to a decrease in the density of the zirconium boride material, resulting in a lower thermal conductivity of the ceramic electrode.

[0008] In summary, existing electrodes for electric arc furnaces have the following technical defects: poor wear resistance, poor fracture toughness, low electrical conductivity and low thermal conductivity. Summary of the Invention

[0009] The present invention aims to overcome the shortcomings of the existing technology and has the purpose of providing a method for preparing zirconium boride-based composite ceramic electrodes for electric arc furnaces. The zirconium boride-based composite ceramic electrodes for electric arc furnaces prepared by this method have good wear resistance, excellent fracture toughness, high electrical conductivity and excellent thermal conductivity.

[0010] To achieve the above object, the specific steps of the technical solution adopted by the present invention are:

[0011] Step 1: First, 85-95wt% of zirconium boride powder, 2-5wt% of zirconium carbide powder, 2.5-8wt% of silicon powder and 0.5-2wt% of tungsten powder are mixed, then ball milled for 8-10 hours and dried to obtain a composite powder.

[0012] Step 2: Pressing the composite powder into a shape under a pressure of 100 to 120 MPa, and then performing cold isostatic pressing to obtain a ceramic body.

[0013] Step 3: placing the ceramic body in a vacuum induction furnace and performing vacuum induction sintering to obtain a zirconium boride-based composite ceramic electrode for an electric arc furnace.

[0014] The process of vacuum induction sintering is as follows: first open the circulating water valve, then turn on the power of the induction furnace, and -2 ~10 -1 MPa, first heat to 800-900℃ at a power of 8-15kw, then heat to 1500-1600℃ at a power of 16-20kw, keep warm for 0.5-1.5h, turn off the power of the induction furnace, keep the circulating water valve open for 2-5h, and then close the circulating water valve.

[0015] The particle size of the zirconium boride powder is 1 to 3 μm; the purity of the zirconium boride powder is 99.9%.

[0016] The particle size of the zirconium carbide powder is 1-3 μm, and the purity of the zirconium carbide powder is 99%.

[0017] The particle size of the silicon powder is 1-5 μm, and the purity of the silicon powder is 99%.

[0018] The particle size of the tungsten powder is 1-5 μm, and the purity of the tungsten powder is 99.9%.

[0019] The ball milling process is as follows: the rotation speed is 600-800 rpm, the ball milling medium is anhydrous ethanol, the grinding ball material is zirconia, and the mass ratio of grinding ball to mixed powder is 1-4:1.

[0020] The cold isostatic pressing process:

[0021] First, increase the pressure at the following rates: increase the pressure to 30-50 MPa at a rate of 0.1-4 MPa / s, increase the pressure to 60-80 MPa at a rate of 0.1-10 MPa / s, increase the pressure to 90-110 MPa at a rate of 0.1-6 MPa / s, increase the pressure to 120-140 MPa at a rate of 0.1-8 MPa / s, and increase the pressure to 150-200 MPa at a rate of 0.1-8 MPa / s, and maintain the pressure for 3-5 minutes;

[0022] Then reduce the pressure at the following rates in sequence: reduce the pressure to 120-140 MPa at a rate of 0.1-5 MPa / s, reduce the pressure to 90-110 MPa at a rate of 0.1-6 MPa / s, reduce the pressure to 60-80 MPa at a rate of 0.1-8 MPa / s, reduce the pressure to 30-50 MPa at a rate of 0.1-5 MPa / s, reduce the pressure to 2 MPa at a rate of 0.1-5 MPa / s, and unload to normal pressure.

[0023] Due to the adoption of the above technical solution, the present invention has the following positive effects compared with the prior art:

[0024] (1) The present invention fully utilizes the high electrical conductivity of the zirconium boride material itself and the reactivity of zirconium carbide powder, silicon powder, and tungsten powder at high temperatures to regulate the in-situ formation of bonding phases such as zirconium-tungsten alloy, zirconium silicide, and silicon carbide between the zirconium boride powder particles, thereby synergistically improving the electrical and thermal conductivity of the zirconium boride-based composite ceramic electrode for electric arc furnaces. Therefore, the zirconium boride-based composite ceramic electrode for electric arc furnaces produced by the present invention has high electrical conductivity and excellent thermal conductivity.

[0025] (2) The present invention utilizes the reaction between zirconium carbide powder, silicon powder, and tungsten powder during vacuum induction sintering to in-situ form zirconium-tungsten alloy, zirconium silicide, and silicon carbide between the zirconium boride particles, thereby strengthening the bond between the zirconium boride powder particles. The volume deformation during the reaction process is utilized to adjust the pore structure between the particles and the densification behavior of the material during sintering. As a result, the zirconium boride-based composite ceramic electrode for electric arc furnaces produced by the present invention has excellent fracture toughness and wear resistance.

[0026] The boride zirconium-based composite ceramic electrode for electric arc furnace prepared by the present invention is tested to have the following characteristics: Vickers hardness ≥ 15GPa; fracture toughness ≥ 4.2MPa·m 1 / 2 ; Flexural strength ≥ 220MPa; Electrical conductivity ≥ 6×10 6 S / m; thermal conductivity ≥70W / (m·K); bulk density ≥4.55g / cm 3 .

[0027] Therefore, the zirconium boride-based composite ceramic electrode for electric arc furnace prepared by the present invention has good wear resistance, excellent fracture toughness, high electrical conductivity and excellent thermal conductivity. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with specific embodiments, which does not limit the scope of protection thereof.

[0029] A zirconium boride-based composite ceramic electrode for an electric arc furnace and a preparation method thereof. The preparation method described in this specific embodiment is:

[0030] Step 1: First, 85-95wt% of zirconium boride powder, 2-5wt% of zirconium carbide powder, 2.5-8wt% of silicon powder and 0.5-2wt% of tungsten powder are mixed, then ball milled for 8-10 hours and dried to obtain a composite powder.

[0031] Step 2: Pressing the composite powder into a shape under a pressure of 100 to 120 MPa, and then performing cold isostatic pressing to obtain a ceramic body.

[0032] Step 3: placing the ceramic body in a vacuum induction furnace and performing vacuum induction sintering to obtain a zirconium boride-based composite ceramic electrode for an electric arc furnace.

[0033] The process of vacuum induction sintering is as follows: first open the circulating water valve, then turn on the power of the induction furnace, and -2 ~10 -1 MPa, first heat to 800-900℃ at a power of 8-15kw, then heat to 1500-1600℃ at a power of 16-20kw, keep warm for 0.5-1.5h, turn off the power of the induction furnace, keep the circulating water valve open for 2-5h, and then close the circulating water valve.

[0034] The ball milling process is as follows: the rotation speed is 600-800 rpm, the ball milling medium is anhydrous ethanol, the grinding ball material is zirconia, and the mass ratio of grinding ball to mixed powder is 1-4:1.

[0035] The cold isostatic pressing process:

[0036] First, increase the pressure at the following rates: increase the pressure to 30-50 MPa at a rate of 0.1-4 MPa / s, increase the pressure to 60-80 MPa at a rate of 0.1-10 MPa / s, increase the pressure to 90-110 MPa at a rate of 0.1-6 MPa / s, increase the pressure to 120-140 MPa at a rate of 0.1-8 MPa / s, and increase the pressure to 150-200 MPa at a rate of 0.1-8 MPa / s, and maintain the pressure for 3-5 minutes;

[0037] Then reduce the pressure at the following rates in sequence: reduce the pressure to 120-140 MPa at a rate of 0.1-5 MPa / s, reduce the pressure to 90-110 MPa at a rate of 0.1-6 MPa / s, reduce the pressure to 60-80 MPa at a rate of 0.1-8 MPa / s, reduce the pressure to 30-50 MPa at a rate of 0.1-5 MPa / s, reduce the pressure to 2 MPa at a rate of 0.1-5 MPa / s, and unload to normal pressure.

[0038] In this specific implementation mode:

[0039] The particle size of the zirconium boride powder is 1 to 3 μm; the purity of the zirconium boride powder is 99.9%;

[0040] The particle size of the zirconium carbide powder is 1 to 3 μm, and the purity of the zirconium carbide powder is 99%;

[0041] The particle size of the silicon powder is 1 to 5 μm, and the purity of the silicon powder is 99%;

[0042] The particle size of the tungsten powder is 1-5 μm, and the purity of the tungsten powder is 99.9 t%.

[0043] The details will not be described in detail in the embodiments.

[0044] Example 1

[0045] A zirconium boride-based composite ceramic electrode for an electric arc furnace and a preparation method thereof. The preparation method described in this embodiment is:

[0046] Step 1: 85 wt% of zirconium boride powder, 5 wt% of zirconium carbide powder, 8 wt% of silicon powder and 2 wt% of tungsten powder are mixed, then ball milled for 8 h using a ball mill and dried to obtain a composite powder.

[0047] Step 2: Pressing the composite powder into a shape under 100 MPa, and then performing cold isostatic pressing to obtain a ceramic body.

[0048] Step 3: placing the ceramic body in a vacuum induction furnace and performing vacuum induction sintering to obtain a zirconium boride-based composite ceramic electrode for an electric arc furnace.

[0049] The process of vacuum induction sintering is as follows: first open the circulating water valve, then turn on the power of the induction furnace, and -2 MPa, first heat to 800℃ at a power of 8kW, then heat to 1500℃ at a power of 16kW, keep warm for 0.5h, turn off the power of the induction furnace, keep the circulating water valve open for 2h, and then close the circulating water valve.

[0050] The ball milling process is as follows: the rotation speed is 600 rpm, the ball milling medium is anhydrous ethanol, the grinding ball material is zirconia, and the mass ratio of grinding ball to mixed powder is 1:1.

[0051] The cold isostatic pressing process:

[0052] First, increase the pressure at the following rates: 0.1 MPa / s to 30 MPa, 0.1 MPa / s to 60 MPa, 0.1 MPa / s to 90 MPa, 0.1 MPa / s to 120 MPa, and 0.1 MPa / s to 150 MPa, and maintain the pressure for 3 minutes.

[0053] Then reduce the pressure at the following rates in sequence: reduce the pressure to 140MPa at a rate of 0.1MPa / s, reduce the pressure to 110MPa at a rate of 0.1MPa / s, reduce the pressure to 80MPa at a rate of 0.1MPa / s, reduce the pressure to 50MPa at a rate of 0.1MPa / s, reduce the pressure to 2MPa at a rate of 0.1MPa / s, and unload to normal pressure.

[0054] The boride zirconium-based composite ceramic electrode for arc furnace prepared in this embodiment was tested to have a Vickers hardness of 15.1 GPa and a fracture toughness of 4.6 MPa·m 1 / 2 ; flexural strength is 239MPa; electrical conductivity is 6.1×10 6 S / m; thermal conductivity is 75.5W / (m·K); bulk density is 4.58g / cm 3 .

[0055] Example 2

[0056] A zirconium boride-based composite ceramic electrode for an electric arc furnace and a preparation method thereof. The preparation method described in this embodiment is:

[0057] Step 1: 89 wt% of zirconium boride powder, 4 wt% of zirconium carbide powder, 5.5 wt% of silicon powder and 1.5 wt% of tungsten powder are mixed, then ball milled for 9 hours using a ball mill and dried to obtain a composite powder.

[0058] Step 2: Pressing the composite powder into a shape under a pressure of 110 MPa, and then performing cold isostatic pressing to obtain a ceramic body.

[0059] Step 3: placing the ceramic body in a vacuum induction furnace and performing vacuum induction sintering to obtain a zirconium boride-based composite ceramic electrode for an electric arc furnace.

[0060] The process of vacuum induction sintering is as follows: first open the circulating water valve, then turn on the power of the induction furnace, and -2 MPa, first heat to 830℃ at a power of 10kW, then heat to 1550℃ at a power of 18kW, keep warm for 0.8h, turn off the power of the induction furnace, keep the circulating water valve open for 3h, and then close the circulating water valve.

[0061] The ball milling process is as follows: the rotation speed is 700 rpm, the ball milling medium is anhydrous ethanol, the grinding ball material is zirconia, and the mass ratio of grinding ball to mixed powder is 2:1.

[0062] The cold isostatic pressing process:

[0063] First, increase the pressure at the following rates: 1 MPa / s to 40 MPa, 2 MPa / s to 70 MPa, 4 MPa / s to 100 MPa, 2 MPa / s to 130 MPa, and 3 MPa / s to 165 MPa, and maintain the pressure for 4 minutes.

[0064] Then reduce the pressure at the following rates in sequence: reduce the pressure to 130MPa at a rate of 2MPa / s, reduce the pressure to 100MPa at a rate of 2MPa / s, reduce the pressure to 70MPa at a rate of 3MPa / s, reduce the pressure to 40MPa at a rate of 2MPa / s, reduce the pressure to 2MPa at a rate of 2MPa / s, and unload to normal pressure.

[0065] The boride zirconium-based composite ceramic electrode for arc furnace prepared in this embodiment was tested to have a Vickers hardness of 15.8 GPa and a fracture toughness of 4.3 MPa·m 1 / 2 ; flexural strength is 235MPa; electrical conductivity is 6.5×10 6 S / m; thermal conductivity is 73.7W / (m·K); bulk density is 4.64g / cm 3 .

[0066] Example 3

[0067] A zirconium boride-based composite ceramic electrode for an electric arc furnace and a preparation method thereof. The preparation method described in this embodiment is:

[0068] Step 1: First, 93 wt% of zirconium boride powder, 3 wt% of zirconium carbide powder, 3 wt% of silicon powder and 1 wt% of tungsten powder are mixed, and then ball milled for 9.5 hours using a ball mill, and dried to obtain a composite powder.

[0069] Step 2: Pressing the composite powder into a shape under a pressure of 115 MPa, and then performing cold isostatic pressing to obtain a ceramic body.

[0070] Step 3: placing the ceramic body in a vacuum induction furnace and performing vacuum induction sintering to obtain a zirconium boride-based composite ceramic electrode for an electric arc furnace.

[0071] The process of vacuum induction sintering is as follows: first open the circulating water valve, then turn on the power of the induction furnace, and -1 MPa, first heat to 860℃ at a power of 13kw, then heat to 1580℃ at a power of 19kw, keep warm for 1.2h, turn off the power of the induction furnace, keep the circulating water valve open for 4h, and then close the circulating water valve.

[0072] The ball milling process is as follows: the rotation speed is 750 rpm, the ball milling medium is anhydrous ethanol, the grinding ball material is zirconia, and the mass ratio of grinding ball to mixed powder is 3:1.

[0073] The cold isostatic pressing process:

[0074] First, increase the pressure at the following rates: 2 MPa / s to 45 MPa, 4 MPa / s to 75 MPa, 7 MPa / s to 105 MPa, 4 MPa / s to 135 MPa, and 5 MPa / s to 180 MPa, and maintain the pressure for 3.5 min.

[0075] Then reduce the pressure at the following rates in sequence: reduce the pressure to 125MPa at a rate of 3MPa / s, reduce the pressure to 95MPa at a rate of 4MPa / s, reduce the pressure to 65MPa at a rate of 5MPa / s, reduce the pressure to 35MPa at a rate of 3MPa / s, reduce the pressure to 2MPa at a rate of 3MPa / s, and unload to normal pressure.

[0076] The boride zirconium-based composite ceramic electrode for arc furnace prepared in this embodiment was tested to have a Vickers hardness of 15.3 GPa and a fracture toughness of 4.5 MPa·m 1 / 2 ; flexural strength is 229MPa; electrical conductivity is 6.9×10 6 S / m; thermal conductivity is 72.2W / (m·K); bulk density is 4.67g / cm 3.

[0077] Example 4

[0078] A zirconium boride-based composite ceramic electrode for an electric arc furnace and a preparation method thereof. The preparation method described in this embodiment is:

[0079] Step 1: 95 wt% of zirconium boride powder, 2 wt% of zirconium carbide powder, 2.5 wt% of silicon powder and 0.5 wt% of tungsten powder are mixed, then ball milled for 10 hours and dried to obtain a composite powder.

[0080] Step 2: Pressing the composite powder into a shape under 120 MPa, and then performing cold isostatic pressing to obtain a ceramic body.

[0081] Step 3: placing the ceramic body in a vacuum induction furnace and performing vacuum induction sintering to obtain a zirconium boride-based composite ceramic electrode for an electric arc furnace.

[0082] The process of vacuum induction sintering is as follows: first open the circulating water valve, then turn on the power of the induction furnace, and -1 MPa, first heat to 900℃ at a power of 15kw, then heat to 1600℃ at a power of 20kw, keep warm for 1.5h, turn off the power of the induction furnace, keep the circulating water valve open for 5h, and then close the circulating water valve.

[0083] The ball milling process is as follows: the rotation speed is 800 rpm, the ball milling medium is anhydrous ethanol, the grinding ball material is zirconia, and the mass ratio of grinding ball to mixed powder is 4:1.

[0084] The cold isostatic pressing process:

[0085] First, increase the pressure at the following rates: 4 MPa / s to 50 MPa, 5 MPa / s to 80 MPa, 10 MPa / s to 110 MPa, 6 MPa / s to 140 MPa, and 8 MPa / s to 200 MPa, and maintain the pressure for 5 minutes.

[0086] Then reduce the pressure at the following rates in sequence: reduce the pressure to 120MPa at a rate of 5MPa / s, reduce the pressure to 90MPa at a rate of 6MPa / s, reduce the pressure to 60MPa at a rate of 8MPa / s, reduce the pressure to 30MPa at a rate of 5MPa / s, reduce the pressure to 2MPa at a rate of 5MPa / s, and unload to normal pressure.

[0087] The boride zirconium-based composite ceramic electrode for arc furnace prepared in this embodiment was tested to have a Vickers hardness of 16.3 GPa and a fracture toughness of 4.2 MPa·m 1 / 2 ; flexural strength is 221MPa; electrical conductivity is 7.1×106 S / m; thermal conductivity is 71.8W / (m·K); bulk density is 4.72g / cm 3 .

[0088] Compared with the prior art, this embodiment has the following positive effects:

[0089] (1) This embodiment fully utilizes the high electrical conductivity of the zirconium boride material itself and the reactivity of zirconium carbide powder, silicon powder, and tungsten powder at high temperatures to regulate the in-situ formation of bonding phases such as zirconium-tungsten alloy, zirconium silicide, and silicon carbide between the zirconium boride powder particles, thereby synergistically improving the electrical and thermal conductivity of the zirconium boride-based composite ceramic electrode for electric arc furnaces. Therefore, the zirconium boride-based composite ceramic electrode for electric arc furnaces produced by this embodiment has high electrical conductivity and excellent thermal conductivity.

[0090] (2) This embodiment utilizes the reaction between zirconium carbide powder, silicon powder, and tungsten powder during vacuum induction sintering to in-situ form zirconium-tungsten alloy, zirconium silicide, and silicon carbide between the zirconium boride particles, thereby strengthening the bond between the zirconium boride powder particles. The volume deformation during the reaction process is utilized to adjust the pore structure between the particles and the densification behavior of the material during sintering. Therefore, the zirconium boride-based composite ceramic electrode for electric arc furnaces produced in this embodiment exhibits excellent fracture toughness and wear resistance.

[0091] The boride zirconium-based composite ceramic electrode for arc furnace prepared in this embodiment has the following test results: Vickers hardness ≥ 15GPa; fracture toughness ≥ 4.2MPa·m 1 / 2 ; Flexural strength ≥ 220MPa; Electrical conductivity ≥ 6×10 6 S / m; thermal conductivity ≥70W / (m·K); bulk density ≥4.55g / cm 3 .

[0092] The test standards for the performance indicators involved in the embodiments of this specific embodiment are as follows: Vickers hardness is measured in accordance with the national standard GB / T16534-2009; fracture toughness is measured in accordance with the standard GB / T23806-2009; flexural strength is measured in accordance with the standard GB / T4741-1999; electrical conductivity is measured in accordance with the standard GB / T11007-2008; thermal conductivity is measured in accordance with the standard GB / T5990-2021; and bulk density is measured in accordance with the standard GB / T2999-2016.

[0093] Therefore, the zirconium boride-based composite ceramic electrode for an electric arc furnace prepared in this specific embodiment has good wear resistance, excellent fracture toughness, high electrical conductivity and excellent thermal conductivity.

Claims

1. A method for preparing a zirconium boride-based composite ceramic electrode for an electric arc furnace, characterized in that The steps of the preparation method are: Step 1: 85-95 wt% of zirconium boride powder, 2-5 wt% of zirconium carbide powder, 2.5-8 wt% of silicon powder and 0.5-2 wt% of tungsten powder are mixed, and then ball milled for 8-10 hours and dried to obtain a composite powder; Step 2: pressing the composite powder under a pressure of 100-120 MPa, and then performing cold isostatic pressing to obtain a ceramic body; Step 3: placing the ceramic body in a vacuum induction furnace and performing vacuum induction sintering to obtain a zirconium boride-based composite ceramic electrode for an electric arc furnace; The process of vacuum induction sintering is as follows: first open the circulating water valve, then turn on the power of the induction furnace, and -2 ~10 -1 MPa, first heat to 800~900℃ at a power of 8~15kW, then heat to 1500~1600℃ at a power of 16~20kW, keep warm for 0.5~1.5h, turn off the power of the induction furnace, keep the circulating water valve open for 2~5h, and then close the circulating water valve.

2. The method for preparing the zirconium boride-based composite ceramic electrode for electric arc furnace according to claim 1, characterized in that The particle size of the zirconium boride powder is 1-3 μm; the purity of the zirconium boride powder is 99.9%.

3. The method for preparing the zirconium boride-based composite ceramic electrode for electric arc furnace according to claim 1, characterized in that The particle size of the zirconium carbide powder is 1-3 μm, and the purity of the zirconium carbide powder is 99%.

4. The method for preparing the zirconium boride-based composite ceramic electrode for electric arc furnace according to claim 1, characterized in that The particle size of the silicon powder is 1-5 μm, and the purity of the silicon powder is 99%.

5. The method for preparing the zirconium boride-based composite ceramic electrode for electric arc furnace according to claim 1, characterized in that The particle size of the tungsten powder is 1-5 μm, and the purity of the tungsten powder is 99.9%.

6. The method for preparing the zirconium boride-based composite ceramic electrode for electric arc furnace according to claim 1, characterized in that The ball milling process is as follows: the rotation speed is 600-800 rpm, the ball milling medium is anhydrous ethanol, the grinding ball material is zirconia, and the mass ratio of grinding ball to mixed powder is 1-4:

1.

7. The method for preparing the zirconium boride-based composite ceramic electrode for electric arc furnace according to claim 1, characterized in that The process of cold isostatic pressing: First, increase the pressure at the following rates: 0.1-4 MPa / s to 30-50 MPa, 0.1-5 MPa / s to 60-80 MPa, 0.1-10 MPa / s to 90-110 MPa, 0.1-6 MPa / s to 120-140 MPa, and 0.1-8 MPa / s to 150-200 MPa, and maintain the pressure for 3-5 minutes. Then reduce the pressure at the following rates in sequence: reduce the pressure to 120~140MPa at a rate of 0.1~5MPa / s, reduce the pressure to 90~110MPa at a rate of 0.1~6MPa / s, reduce the pressure to 60~80MPa at a rate of 0.1~8MPa / s, reduce the pressure to 30~50MPa at a rate of 0.1~5MPa / s, reduce the pressure to 2MPa at a rate of 0.1~5MPa / s, and unload to normal pressure.

8. A zirconium boride-based composite ceramic electrode for an electric arc furnace, characterized in that The zirconium boride-based composite ceramic electrode for an electric arc furnace is prepared according to the method for preparing a zirconium boride-based composite ceramic electrode for an electric arc furnace according to any one of claims 1 to 7.