Ultrahigh-temperature high-resistance electrothermal alloy and production process
By employing novel composition design and vacuum smelting processes, the problems of unstable resistance and high-temperature collapse in ultra-high temperature electrothermal alloy products have been solved, achieving consistent resistivity and high performance, reducing production costs, and improving product quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIANGSU SHENYUAN SPECIAL STEEL
- Filing Date
- 2026-01-23
- Publication Date
- 2026-05-01
AI Technical Summary
Due to the influence of composition design, domestic ultra-high temperature series electrothermal alloy products suffer from inconsistent elemental billet losses, unstable resistance, and frequent high-temperature collapse during the electroslag process, failing to meet market demands.
A new composition design is adopted, including the addition of trace alloying elements and rare earth elements. Combined with vacuum smelting and vacuum consumable refining processes, the yield of trace elements and rare earth elements is ensured. The alloy is smelted and forged using equipment such as vacuum smelting furnaces and vacuum consumable electric arc furnaces to form a high-resistance electrothermal alloy.
This achieves consistent and stable resistivity, reduces processing costs, improves product performance and overall cost-effectiveness, and extends service life.
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Figure CN121951384A_ABST
Abstract
Description
A high-temperature, high-resistance electrothermal alloy and its manufacturing process Technical Field
[0001] This invention belongs to the field of ultra-high temperature high resistance electrothermal alloy preparation technology, specifically an ultra-high temperature high resistance electrothermal alloy and its production process. Background Technology
[0002] High-resistance electric heating alloys are a branch of special steels. While their production processes share many similarities with special steel products, their characteristics in my country's electric heating alloy industry include small production scale, numerous varieties and specifications, low demand, difficulty in centralized production, and specific application requirements. These characteristics hinder product quality improvement and technological advancement. Ultra-high temperature electric heating alloys are mainly used in electric heating elements for single-crystal diffusion furnaces, powder metallurgy sintering furnaces, ceramic calcining furnaces, and high-temperature heat treatment radiation furnaces, operating at temperatures between 1200 and 1300℃ (the alloy material itself reaches 1400℃). In recent years, they have also been applied in industries requiring longer furnace lifespans, such as photovoltaics and lithium batteries.
[0003] Internationally, leading brands of electrothermal alloys from countries such as Sweden's Kanthal, Russia's 3H626, Germany's Megapyr, and the United States' NichromeheChromel hold leading positions on the international stage. In particular, Kanthal of Sweden has been committed to the research and development of electrothermal alloys and is at the forefront internationally. Currently, domestic ultra-high temperature series products suffer from inconsistent elemental billet losses at the beginning and end due to the influence of composition design in the electroslag process. This leads to unstable resistance and frequent high-temperature collapse during use. Market feedback has not been able to resolve these issues, and the overall product performance is significantly inferior to that of similar international products.
[0004] In the above-mentioned solutions, the current domestic ultra-high temperature series products suffer from inconsistent elemental billet losses at the beginning and end due to the influence of composition design in the electroslag process. This leads to unstable resistance and frequent high-temperature collapse during use, resulting in unmet market demand for this ultra-high temperature series of electrothermal alloy products. Therefore, this invention provides an ultra-high temperature high resistance electrothermal alloy and its production process. Summary of the Invention
[0005] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.
[0006] The technical solution adopted by the present invention to solve its technical problem is as follows: The ultra-high temperature high resistance electrothermal alloy of the present invention comprises the following components: C 0.010%-0.030% P 0.020%-0.025% S 0.010%-0.020% Mn 0.050%-0.60% Si 0.050%-0.60% Cr 21.50%-22.50% Al 5.20%-5.70% Zr 0.15%-0.25% Co 0.80%-1.60% Ti 0.15%-0.22% La(Y) 0.06%-0.16% Nb 0.20%-0.30% with the balance being Fe and unavoidable impurities.
[0007] Preferably, the C is ultra-low carbon C.
[0008] Preferably, the ultra-high temperature high resistance electric heating alloy comprises the following components: C 0.030%, P 0.025%, S 0.020%, Mn 0.60%, Si 0.60%, Cr 21%, Al 5.25%, Zr 0.20%, Co 1.50%, Ti 0.20%, La(Y) 0.08%, Nb 0.25%, with the balance being Fe and unavoidable impurities.
[0009] A high-temperature, high-resistance electric heating alloy is prepared according to the following process: (1) the high-temperature, high-resistance electric heating alloy is batched according to the above formula; (2) vacuum smelting is carried out by feeding the batched high-temperature, high-resistance electric heating alloy raw materials into a vacuum smelting furnace. After the loading is completed, the furnace door is closed and the fixing bolts are tightened. Then, the melting period is entered, and the high-temperature, high-resistance electric heating alloy raw materials are heated for 40 minutes to 1550-1570℃ to completely melt the high-temperature, high-resistance electric heating alloy raw materials. Then, the refining period is entered, and the Roots pump is started to make the vacuum smelting furnace a vacuum state with a vacuum degree of less than 3Pa. Heating was continued for 40 minutes to bring the temperature to 1570℃-1590℃. Temperature measurement and sampling were then carried out, followed by alloying. Argon was purged into the furnace, and then casting was performed to initially form a steel billet. (3) Steel billet surface grinding: The steel billet was ground using a grinding device to remove the oxide film. (4) Vacuum consumable electrode: The ground steel billet was made into a standard columnar consumable electrode. The steel billet was then put into the heating furnace. The gas in the furnace was extracted by the vacuum system to maintain the vacuum level at 1-0.01 Pa. A DC arc was ignited between the consumable electrode and the water-cooled copper crucible to generate a high-temperature melting electrode. Metal drips into a water-cooled crystallizer and rapidly solidifies into ingots. Computer-controlled programmed melting is used. After melting, the vacuum state in the heating furnace is broken by cooling, and then the billet is taken out; (5) Surface peeling of the billet: The oxide scale formed on the surface of the billet is formed by the peeling device and then removed; (6) Forging: The billet with the oxide scale removed is sent to the forging device for forging. The forging temperature of the forging device is 1000℃-1180℃, the initial forging temperature is 1150℃, and natural gas is used for heating; (7) Hot-rolled wire rod: The forged billet is descaled by high-pressure water and enters the high-speed wire rod mill. (8) After being forced to air-cooled to below 600℃ on the Stellmore line, the coils are then rolled into hot-rolled coils; (9) Annealing: the annealing temperature is 950℃-1100℃ and the annealing temperature is maintained for 2 hours; (10) Rinsing: the hot-rolled coils are loaded into a bogie-type annealing furnace within 6 hours, and the furnace temperature is raised to 820℃±10℃ and maintained for 4-4.5 hours before air cooling to eliminate work hardening; then the oxide scale is removed by pickling and water washing; (11) Inspection and warehousing: the surface quality of the wire rods is sampled, the diameter and ellipticity are measured, and the resistance uniformity per meter is tested (deviation ≤1%). After passing the inspection, the wire rods are coated with anti-rust oil and packaged for warehousing, waiting to enter the subsequent multiple cold drawing processes.
[0010] Preferably, in step (2), the vacuum smelting furnace is a vacuum induction melting furnace with an input power of 400–600 kW.
[0011] Preferably, the grinding machine in step (3) is a common suspended grinding wheel with a power of 5-15kW.
[0012] Preferably, the heating furnace in step (4) is a vacuum consumable arc furnace, including a water-cooled copper crucible, a vacuum system, a DC power supply and an electrode driving mechanism.
[0013] Preferably, the peeling device in step (5) is a heavy-duty peeling lathe, which is equipped with hydraulic clamping and CNC tool post, with a power of 45-75kW and a turning depth of 2-3 mm.
[0014] Preferably, the high-speed wire rod mill in step (7) consists of 28-32 mill stands, with a finishing rolling speed of 28-35 m / s, an initial rolling temperature of ≥1050℃, a final rolling temperature of ≥900℃, and the wire rod non-roundness controlled within ±0.15 mm.
[0015] Preferably, in the rinsing and pickling steps described in step (9), the acid solution is prepared in the following weight ratio: HNO3:HF:H2O=1.5:0.8:100, the acid solution temperature is 30-50℃, and the pickling time is 10-12min.
[0016] The beneficial effects of this invention are as follows: 1. The new material composition design adopts a method of adding trace alloying elements and rare earth elements in combination; the new production process uses 1 ton vacuum smelting to ensure product purity, and adopts a 1 ton vacuum self-consumption refining process to achieve 800 kg / piece for a single steel billet, and ensures the consistency of the high resistance and resistivity of the aluminum element in the entire steel billet from the beginning, middle and end, thereby achieving the consistency of resistivity, ensuring that various trace elements and rare earth alloys reach the qualified yield target, and thus achieving the quality stability and excellent performance of the high resistance electrothermal alloy at ultra-high temperature of 1400℃.
[0017] 2. An ultra-high temperature high resistance electrothermal alloy and its production process, which adopts a new production method of vacuum smelting (using micro-alloying and trace addition of rare earth elements in the later stage of refining) plus vacuum self-consumption to ensure the stable yield of micro-alloying and trace amounts of rare earth elements in steel, thereby achieving the target of ultra-high temperature and anti-collapse.
[0018] 3. A high-temperature, high-resistivity electrothermal alloy and its production process. The production process employs a 1-ton vacuum smelting process to ensure product purity. A 1-ton vacuum self-consumption refining process is used to achieve a single steel billet weight of 800 kg / piece. The high-resistivity, stable aluminum element composition is maintained consistently throughout the entire billet, ensuring resistivity uniformity and guaranteeing the acceptable yield of various trace elements and rare earth alloys. Because the billet weight exceeds 800 kg, the weight per piece increases tenfold, significantly reducing labor costs for subsequent processing such as wire drawing.
[0019] 4. A high-temperature, high-resistivity electric heating alloy and its production process, which increases the weight of a single product by 10 times, achieves the best resistivity uniformity, and reduces the processing costs of subsequent processes: A new high-temperature 1400℃ high-resistivity electric heating alloy, due to its better process stability and the successful implementation of a large steel billet production method, achieves industry-leading resistivity uniformity of a single piece (800 kg), and significantly reduces the overall cost of subsequent production processes.
[0020] 5. An ultra-high temperature high resistance electrothermal alloy and its production process, due to the reasonable design of the new composition and the overall implementation of the new production process, has been effectively improved in many aspects compared with traditional products, such as reasonable composition setting, high element recovery rate, and more effective process assurance. The product performance is better, the production cost is significantly reduced, and the overall cost performance is improved by more than 50%. Attached Figure Description
[0021] The invention will now be further described with reference to the accompanying drawings.
[0022] Figure 1 is a schematic diagram of the processing flow of an ultra-high temperature high resistance electrothermal alloy and its production process according to the present invention. Detailed Implementation
[0023] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.
[0024] A high-temperature high-resistance electric heating alloy is prepared according to the following process: (1) The high-temperature high-resistance electric heating alloy is batched according to the above formula; ultra-low carbon C is used to achieve good plasticity index and easy processing requirements; the reasonable addition of Cr and Al elements ensures the enhancement of the product's oxidation resistance and focuses on obtaining the required high resistivity; a small amount of Co and Nb is added to improve high-temperature strength, reduce high-temperature creep and high-temperature collapse, and extend service life; a small amount of Ti can refine the grains and help enhance the high-temperature strength and high-temperature oxidation resistance of the alloy; a trace amount of La (Y) rare earth can significantly improve service life. The reasonable control of Si content ensures the integrity of the Al2O3 film and achieves good oxidation resistance; the strict control of P and S reduces the generation of low-melting-point brittle substances and prevents hot brittleness; the reasonable addition of trace element Zr can significantly refine the grains, effectively hinder the grain growth behavior of the alloy at long-term high temperature, and has excellent high-temperature oxidation resistance, thereby improving the service life of the alloy.
[0025] (2) Vacuum smelting: The prepared ultra-high temperature and high resistance electric heating alloy raw materials are put into the vacuum smelting furnace. After the loading is completed, the furnace door is closed and the fixing bolts are tightened. Then the melting period is entered. The ultra-high temperature and high resistance electric heating alloy raw materials are heated for 40 minutes to 1550-1570℃ so that the ultra-high temperature and high resistance electric heating alloy raw materials are completely melted. Then the refining period is entered. The Roots pump is started to put the vacuum smelting furnace into a vacuum state with a vacuum degree of less than 3Pa. The heating is continued for 40 minutes to keep the temperature at 1570℃-1590℃. Then temperature measurement and sampling are carried out. Then alloying is carried out. Argon is filled into the furnace and then casting is carried out to initially form a steel billet. After alloying is completed, before tapping the steel, trace alloy Zr and rare earth elements La and Y are added to ensure that the recovery rate of trace elements and rare earth elements can meet the required target. The role of vacuum smelting is a metallurgical technology that melts metals by electromagnetic induction heating in a vacuum environment. During smelting, the alternating magnetic field is used to generate eddy current heating of the metal, which can avoid air impurity pollution.
[0026] (3) Steel billet surface grinding: The steel billet that has been initially formed is ground using a grinding device to remove the oxide film; (4) Vacuum consumable electrode: The ground steel billet is made into a standard columnar consumable electrode, and then the steel billet is put into the heating furnace. The gas in the furnace is extracted by the vacuum system to maintain the vacuum degree at 1-0.01 Pa. A DC arc is ignited between the consumable electrode and the water-cooled copper crucible to generate a high-temperature melting electrode. The molten metal drips into the water-cooled crystallizer and quickly solidifies into an ingot. Computer-controlled programmed melting is used. After melting is completed, the vacuum state in the heating furnace is broken by cooling, and then the steel billet is taken out; Vacuum consumable smelting is a remelting technology that uses the material being melted as the consumable electrode in a vacuum furnace. The process involves melting electrodes at high temperatures using an electric arc, with the molten droplets solidifying into ingots. Key features include rapid melting and solidification to reduce impurities, and improved microstructure uniformity through directional solidification. A vacuum consumable process replaces the traditional electroslag process, ensuring an overall recovery rate of over 95% for trace elements and rare earth elements, consistently achieving the set target values. The production process employs 1-ton vacuum smelting to guarantee product purity. This 1-ton vacuum consumable refining process achieves a single billet weight of 800 kg, ensuring consistent high resistivity and stable aluminum content throughout the billet, thus guaranteeing consistent resistivity and ensuring qualified recovery rates for various trace elements and rare earth alloys. Because the billet weight exceeds 800 kg, the weight per piece increases tenfold, significantly reducing labor costs for subsequent processing such as wire drawing.
[0027] (5) Peeling the surface of the billet: using a peeling device to form an oxide scale on the cooled surface of the billet, and removing the oxide scale formed on the surface of the billet; conventional billet surface peeling operation is to machine all the oxide layer, cracks and inclusions on the surface of the billet to ensure that there are no defects on the surface during subsequent forging or rolling.
[0028] (6) Forging: The steel billet after removing the oxide scale is sent to the forging device for forging. The forging temperature of the forging device is 1000℃-1180℃, the initial forging temperature is 1150℃, and natural gas is used for heating; (7) Hot-rolled wire rod: The forged steel billet is descaled by high-pressure water and enters the high-speed wire rod mill. The wire rod is forced to be cooled to below 600℃ by the Steyrmo line, and then coiled into a hot-rolled coil; (8) Annealing: The annealing temperature is 950℃-1100℃. Annealing and holding for 2 hours; (9) Rinsing: Hot-rolled coils are loaded into a bogie-type annealing furnace within 6 hours, heated to 820℃±10℃ and held for 4-4.5 hours before air cooling to eliminate work hardening; then pickled and washed to remove oxide scale; (10) Inspection and warehousing: Surface quality inspection, diameter and ovality measurement, and resistance uniformity test per meter (deviation ≤1%) are carried out on the wire rods. After passing the inspection, anti-rust oil is applied and the wire rods are packaged and stored in the warehouse, waiting to enter the subsequent multiple cold drawing processes.
[0029] Specifically, in step (2), the vacuum smelting furnace is a vacuum induction melting furnace with an input power of 400–600kW.
[0030] Specifically, the grinding machine mentioned in step (3) uses a common suspended grinding wheel and a 5-15kW class grinding machine.
[0031] Specifically, the heating furnace in step (4) is a vacuum consumable arc furnace, which includes a water-cooled copper crucible, a vacuum system, a DC power supply and an electrode drive mechanism.
[0032] Specifically, in step (5), the peeling device uses a heavy-duty peeling lathe, which is equipped with hydraulic clamping and CNC tool post, with a power of 45-75kW and a cutting depth of 2-3 mm.
[0033] Specifically, the high-speed wire rod mill mentioned in step (7) consists of 28-32 mill stands, with a finishing rolling speed of 28-35 m / s, an initial rolling temperature of ≥1050℃, a final rolling temperature of ≥900℃, and the wire rod non-roundness controlled within ±0.15 mm.
[0034] Specifically, in step (9), the acid solution in the rinsing and pickling steps is prepared in the following weight ratios: HNO3:HF:H2O = 1.5:0.8:100, the acid solution temperature is 30-50℃, and the pickling time is 10-12 minutes. Example 1
[0035] An ultra-high temperature, high resistance heating alloy comprises the following components: C 0.030%, P 0.025%, S 0.020%, Mn 0.60%, Si 0.60%, Cr 21%, Al 5.25%, Zr 0.20%, Co 1.50%, Ti 0.20%, La(Y) 0.08%, Nb 0.25%, with the balance being Fe and unavoidable impurities. Example 2
[0036] An ultra-high temperature, high resistance heating alloy comprises the following components: C 0.030%, P 0.025%, S 0.020%, Mn 0.60%, Si 0.60%, Cr 21.5%, Al 5.25%, Zr 0.30%, Co 1.60%, Ti 0.20%, La(Y) 0.08%, Nb 0.20%, with the balance being Fe and unavoidable impurities. Example 3
[0037] An ultra-high temperature, high resistance heating alloy comprises the following components: C 0.030%, P 0.025%, S 0.020%, Mn 0.60%, Si 0.60%, Cr 22%, Al 5.25%, Zr 0.20%, Co 1.30%, Ti 0.15%, La(Y) 0.08%, Nb 0.25%, with the balance being Fe and unavoidable impurities. Example 4
[0038] An ultra-high temperature high resistance electric heating alloy comprises the following components: C 0.030%, P 0.025%, S 0.020%, Mn 0.60%, Si 0.60%, Cr 21%, Al 5.50%, Zr 0.15%, Co 1.30%, Ti 0.20%, La(Y) 0.08%, Nb 0.25%, with the balance being Fe and unavoidable impurities.
[0039] Comparative Example 1 is the same as Example 1, except that the mass percentage of Al is 5.55% and the mass percentage of Ti is 0.3%.
[0040] Comparative Example 2 is the same as Example 1, except that the mass percentage of Al is 5.6% and the mass percentage of Ti is 0.35%.
[0041] Comparative Example 3 is the same as Example 1, except that the mass percentage of Si is 0.55% and the mass percentage of Zr is 0.35%. Performance testing: The ultra-high temperature high resistance electrothermal alloys prepared in Examples 1-4 and Comparative Examples 1-3 were tested according to the testing standard GB / T1234-2012. The specific test results are shown in Table 1: Table 1
[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.
Claims
1. A high-temperature, high-resistance electrothermal alloy, characterized in that: The composition, by mass percentage, is as follows: C 0.010%–0.030% P 0.020%–0.025% S 0.010%–0.020% Mn 0.050%–0.60% Si 0.050%–0.60% Cr 21.50%–22.50% Al 5.20%–5.70% Zr 0.15%–0.25% Co 0.80%–1.60% Ti 0.15%–0.22% La(Y) 0.06%–0.16% Nb 0.20%–0.30%, with the balance being Fe and unavoidable impurities.
2. The ultra-high temperature high resistance electrothermal alloy according to claim 1, characterized in that: The C used is ultra-low carbon C.
3. The ultra-high temperature high resistance electrothermal alloy according to claim 1, characterized in that: The composition, by mass percentage, is as follows: C 0.030%, P 0.025%, S 0.020%, Mn 0.60%, Si 0.60%, Cr 21%, Al 5.25%, Zr 0.20%, Co 1.50%, Ti 0.20%, La(Y) 0.08%, Nb 0.25%, with the balance being Fe and unavoidable impurities.
4. The ultra-high temperature high resistance electrothermal alloy according to any one of claims 1-3, characterized in that, The process is as follows: (1) Prepare the ultra-high temperature high resistance electric heating alloy according to the above formula; (2) Vacuum smelting: put the prepared ultra-high temperature high resistance electric heating alloy raw materials into the vacuum smelting furnace. After the loading is completed, close the furnace door and tighten the fixing bolts. Then enter the melting period and heat the ultra-high temperature high resistance electric heating alloy raw materials for 40 minutes to 1550-1570℃ to completely melt the ultra-high temperature high resistance electric heating alloy raw materials. Then enter the refining period: start the Roots pump to make the vacuum smelting furnace a vacuum state with a vacuum degree of less than 3Pa and continue heating for 40 minutes. The temperature is set at 1570℃-1590℃, followed by temperature measurement and sampling, then alloying, argon filling in the furnace, and then casting to initially form a steel billet; (3) Steel billet surface grinding, using a grinding device to grind the initially formed steel billet to remove the oxide film; (4) Vacuum self-consumption, the ground steel billet is made into a standard columnar self-consumption electrode, then the steel billet is put into the heating furnace, the gas in the furnace is extracted by the vacuum system, the vacuum degree is maintained at 1-0.01Pa, a DC arc is ignited between the self-consumption electrode and the water-cooled copper crucible to generate a high-temperature melting electrode, and the molten metal drips onto the water-cooled In the crystallizer, the steel billet is rapidly condensed into an ingot and smelted using a computer-controlled programmed process. After smelting, the vacuum state inside the heating furnace is broken by cooling, and then the steel billet is taken out. (5) Peeling the surface of the steel billet: using a peeling device to form oxide scale on the cooled surface of the steel billet, and removing the oxide scale formed on the surface of the steel billet. (6) Forging: sending the steel billet with the oxide scale removed to the forging device for forging. The forging temperature of the forging device is 1000℃-1180℃, the forging temperature is 1150℃, and natural gas is used for heating. (7) Hot-rolled wire rod: the forged steel billet is descaled by high-pressure water and enters the high-speed wire rod mill. The wire rod is processed by the Styrene-Steel ... The wire rod is forced to air-cool to below 600℃, and then coiled into a hot-rolled coil; (8) Annealing, the annealing temperature is 950℃-1100℃, and the annealing is held for 2 hours; (9) Rinsing, the hot-rolled coil is loaded into a bogie-type annealing furnace within 6 hours, and the furnace is heated to 820℃±10℃ and held for 4-4.5 hours before air cooling to eliminate work hardening; then pickling and water washing are performed to remove oxide scale; (10) Inspection and warehousing, the surface quality of the wire rod is sampled, the diameter and ellipticity are measured, and the resistance uniformity per meter is tested (deviation ≤1%). After passing the inspection, the wire rod is coated with anti-rust oil and packaged for warehousing, waiting to enter the subsequent multiple cold drawing processes.
5. The ultra-high temperature high resistance electrothermal alloy according to claim 4, characterized in that: In step (2), the vacuum smelting furnace is a vacuum induction melting furnace with an input power of 400–600kW.
6. The ultra-high temperature high resistance electrothermal alloy according to claim 4, characterized in that: The grinding machine mentioned in step (3) uses a common suspended grinding wheel and a grinding machine with a power of 5-15kW.
7. The ultra-high temperature high resistance electrothermal alloy according to claim 4, characterized in that: The heating furnace mentioned in step (4) is a vacuum consumable electric arc furnace, which includes a water-cooled copper crucible, a vacuum system, a DC power supply and an electrode driving mechanism.
8. The ultra-high temperature high resistance electrothermal alloy according to claim 4, characterized in that: In step (5), the peeling device uses a heavy-duty peeling lathe, which is equipped with hydraulic clamping and CNC tool post, with a power of 45-75kW and a turning depth of 2-3 mm.
9. The ultra-high temperature high resistance electrothermal alloy according to claim 4, characterized in that: The high-speed wire rod mill mentioned in step (7) consists of 28-32 stands, with a finishing rolling speed of 28-35 m / s, an initial rolling temperature of ≥1050℃, a final rolling temperature of ≥900℃, and the wire rod non-roundness controlled within ±0.15 mm.
10. The ultra-high temperature high resistance electrothermal alloy according to claim 4, characterized in that: In step (9), the acid solution in the rinsing and pickling steps is prepared in the following weight ratio: HNO3:HF:H2O=1.5:0.8:100, the acid solution temperature is 30-50℃, and the acid soaking time is 10-12min.