A non-magnetic wear-resistant nickel-chromium alloy and its smelting method and application

Abstract

The application relates to the field of nickel-chromium alloys, and particularly discloses a non-magnetic wear-resistant nickel-chromium alloy and a smelting method and application thereof. In the application, a brand-new electroslag smelting process is adopted, parameters such as smelting feeding, composite slag system and melting speed are controlled, the quality of the steel ingot smelted by the electroslag process is improved, the hot working plasticity of the obtained steel ingot is effectively improved, the inclusion content is reduced, and the material yield of the steel ingot is improved. The application effectively solves the technical problems that the non-magnetic wear-resistant nickel-chromium alloy in the prior art is seriously dropped in the self-consumption smelting process, the self-consumption ingot is difficult to form, the inclusion content is relatively high, the fracture is serious during hot working, and the material yield is extremely low.

Description

Technical Field

[0001] This invention relates to the field of alloy materials, and specifically discloses a non-magnetic wear-resistant nickel-chromium alloy, its smelting method, and its applications. Background Technology

[0002] Nickel-chromium alloy is a nickel-based chromium-aluminum-titanium alloy, mainly used in the manufacture of bearing inner and outer rings and rolling elements for use in high-temperature, high-vacuum, non-magnetic and oxidizing media, as well as other antimagnetic and wear-resistant transmission components. Due to the above application limitations, nickel-chromium alloy needs to have good wear resistance and antimagnetic properties.

[0003] In existing technologies, the preparation of nickel-chromium alloys mostly employs a combination of vacuum induction and vacuum consumable smelting methods. This process is complex, and the resulting steel ingots are mostly φ305mm in diameter. Furthermore, the consumable smelting process generates severe spalling, which poses difficulties for smelting and increases smelting safety risks. Even if the consumable ingots are successfully smelted, forming them is difficult, resulting in the ingots being unable to be formed during hot working, leading to severe breakage and extremely low yield, with a maximum yield of only 30%. This results in high smelting costs and is unsuitable for large-scale production. Therefore, developing a smelting method for nickel-chromium alloys is of significant practical importance for reducing smelting costs and risks. Summary of the Invention

[0004] To address the technical problems in existing technologies, such as severe spalling during the consumable metallurgy process of nickel-chromium alloys, difficulty in forming consumable ingots, high inclusion content, severe fracture during hot working, and extremely low yield, this invention provides a non-magnetic wear-resistant nickel-chromium alloy, its smelting method, and its application. The non-magnetic wear-resistant nickel-chromium alloy adopts a novel electroslag smelting method. By controlling parameters such as smelting feed, composite slag system, and melting rate, the quality of steel ingots smelted by the electroslag process is improved, its hot working plasticity is enhanced, the inclusion content is reduced, and the steel ingot yield is increased.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] The first part of this invention provides a method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, comprising the following steps:

[0007] Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 60min-90min, add aluminum plate and titanium block, melt at 1500℃-1560℃ when the vacuum degree is ≤5Pa to obtain electrode blank.

[0008] Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as slag material, heat the slag material to melt and pour it into the electroslag furnace crystallizer. Insert the electrode billet into the molten slag material, apply electricity, and perform constant melting rate electroslag remelting at a melting rate of 3.0 kg / min-3.5 kg / min. The resulting molten steel droplets pass through the molten slag layer and solidify into electroslag ingots with a diameter of Φ350 mm-Φ370 mm.

[0009] Step 3: Heat the electroslag ingot to 1120℃-1170℃, hold for 3h-6h, and forge to obtain an intermediate billet;

[0010] Step 4: After grinding the surface of the intermediate billet, heat it to 1120℃-1170℃, hold it for 2h-4h, and roll it to obtain the non-magnetic wear-resistant nickel-chromium alloy.

[0011] Compared to existing technologies, this invention provides a method for smelting non-magnetic wear-resistant nickel-chromium alloys. Unlike traditional vacuum consumable metallurgy, this invention creatively proposes a novel electroslag remelting method. This method produces enlarged ingots of Φ350mm-Φ370mm, which, compared to existing technologies that can only produce steel ingots up to φ300mm, provides larger ingots with higher thermoplasticity and easier shaping, thus improving the yield of nickel-chromium alloys. Furthermore, the electroslag remelting method used in this invention avoids the spalling issues associated with traditional vacuum consumable metallurgy, preventing potential safety accidents during production.

[0012] This invention effectively controls the burn-off of Al and Ti during the smelting process by limiting the feeding sequence, ensuring the stability of the chemical composition and the purity of the steel ingot. The oxide content is significantly lower than that of consumable ingots, avoiding the formation of more inclusions. Furthermore, the electroslag remelting method provided by this invention better controls the segregation of the steel ingot by controlling the melting rate, effectively preventing ingot fracture and low yield during subsequent hot working. The electroslag ingot provided by this invention exhibits superior hot working plasticity, greatly improving the steel ingot yield.

[0013] Preferably, the non-magnetic wear-resistant nickel-chromium alloy comprises the following components in weight percentage: C: 0.01%-0.02%, Cr: 39%-41%, Al: 2.75%-3.15%, Ti: 0.9%-1.15%, Mn≤0.05%, Si≤0.05%, S≤0.02%, P≤0.02%, and the balance Ni and unavoidable impurities.

[0014] Preferably, the mass ratio of each component in the quaternary slag system is CaF2:Al2O3:CaO:MgO = 5-6:1-3:0.8-1:0.8-1.

[0015] The electroslag used in this invention adopts a quaternary slag system, which not only effectively controls the burning loss of Al and Ti during the smelting process and ensures the stability of chemical composition, but also ensures the purity of steel ingots and reduces the content of inclusions in steel.

[0016] Preferably, in step one, the refining temperature is 1500-1560℃.

[0017] Preferably, in step one, the melting time is 60-90 minutes.

[0018] Preferably, in step two, the current applied is 6kA-12kA and the voltage applied is 20V-45V.

[0019] Preferably, in step three, the forging is a three-stage forging process, and the forging temperature is 1150℃-1160℃.

[0020] Preferably, in step four, the rolling is a four-segment rolling process, and the rolling temperature is 1140℃-1170℃.

[0021] More preferably, in the three-stage forging, the first stage forging yields a forging blank with a diameter of Φ250mm-Φ260mm; the second stage forging yields a forging blank with a diameter of Φ200mm-Φ210mm; and the third stage forging yields an intermediate blank with a diameter of Φ150mm-Φ160mm.

[0022] More preferably, in the four-stage rolling process, the first stage produces a bar with a diameter of 85mm-90mm; the second stage produces a bar with a diameter of 65mm-85mm; the third stage produces a bar with a diameter of 55mm-65mm; and the fourth stage produces a bar with a diameter of ≤40mm.

[0023] Preferably, in step four, the diameter of the obtained non-magnetic wear-resistant nickel-chromium alloy rod is ≤40mm.

[0024] The second aspect of the present invention provides a non-magnetic wear-resistant nickel-chromium alloy, which is smelted by the smelting method of the non-magnetic wear-resistant nickel-chromium alloy.

[0025] The third aspect of this invention provides the application of a non-magnetic, wear-resistant nickel-chromium alloy in transmission components.

[0026] In summary, this invention provides a non-magnetic wear-resistant nickel-chromium alloy and creatively proposes a novel electroslag remelting method. By controlling parameters such as smelting feed, melting rate, and multi-element electroslag remelting, the quality of steel ingots smelted by the electroslag process is improved, their hot working plasticity is enhanced, the content of inclusions in the steel is reduced, and the yield of steel ingots is increased from the original 30% to 75%. This effectively solves the technical problems of existing technologies using vacuum consumable metallurgy to smelt nickel-chromium alloys, which suffer from severe shavings during the consumable metallurgy process, difficulty in forming consumable ingots, inability to form them during hot working, severe fractures, high inclusion content, and extremely low yield. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1

[0029] This embodiment provides a method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, comprising the following steps:

[0030] Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 80 min, add aluminum plate and titanium block, melt at 1540℃ for 90 min when the vacuum degree is 3 Pa, and obtain Φ250mm electrode blank.

[0031] Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as the slag material, wherein the mass ratio of each component is CaF2:Al2O3:CaO:MgO=6:2:1:1, the slag material is heated to a molten state and poured into the electroslag furnace crystallizer. The electrode billet is inserted into the composite slag material, and electricity is applied. The current is 8kA and the voltage is 35V. Electroslag remelting is performed at a constant melting rate of 3.2kg / min. The resulting molten steel droplets pass through the molten slag layer, and the electroslag remelted into an electroslag ingot with a diameter of 360mm.

[0032] Step 3: Heat the electroslag ingot to 1150℃ and hold for 4 hours. Perform three-stage forging, maintaining the forging temperature at 1150℃-1160℃. The first forging yields a Φ250mm forging billet; the second forging yields a Φ200mm forging billet; and the third forging yields a Φ150mm intermediate billet.

[0033] Step 4: After smoothing the surface of the intermediate billet, heat it to 1160℃ and hold it for 3 hours. Then, perform four-stage rolling, keeping the intermediate billet temperature at 1150-1160℃. The first stage rolls a bar with a diameter of 88.7mm; the second stage rolls a bar with a diameter of 70.5mm; the third stage rolls a bar with a diameter of 62.4mm; and the fourth stage rolls a non-magnetic wear-resistant nickel-chromium alloy bar with a diameter of 38mm.

[0034] Tests revealed that the obtained non-magnetic wear-resistant nickel-chromium alloy comprises the following components by mass percentage: C: 0.02%, Mn: 0.03%, Si: 0.04%, Cr: 40%, Al: 3.05%, Ti: 1.05%, S: 0.01%, P: 0.01%, and the balance Ni and unavoidable impurities.

[0035] Example 2

[0036] This embodiment provides a method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, comprising the following steps:

[0037] Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 80 min, add aluminum plate and titanium block, melt at 1540℃ for 90 min when the vacuum degree is 3 Pa, and obtain Φ250mm electrode blank.

[0038] Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as the slag material, wherein the mass ratio of each component is CaF2:Al2O3:CaO:MgO=6:2:0.9:1, the slag material is heated to a molten state and poured into an electroslag furnace crystallizer. The electrode billet is inserted into the composite slag material, and an electric current of 8kA and an electric voltage of 35V are applied. Electroslag remelting is performed at a constant melting rate of 3.3kg / min. The resulting molten steel droplets pass through the molten slag layer, and the electroslag remelted into an electroslag ingot with a diameter of 360mm.

[0039] Step 3: Heat the electroslag ingot to 1150℃ and hold for 4 hours. Perform three-stage forging, keeping the forging temperature at 1150℃-1160℃. The first forging yields a Φ255mm forging billet; the second forging yields a Φ210mm forging billet; and the third forging yields a Φ160mm intermediate billet.

[0040] Step 4: After smoothing the surface of the intermediate billet, heat it to 1170℃ and hold it for 3 hours. Then, perform four-stage rolling, keeping the temperature of the intermediate billet at 1150-1160℃. The first stage rolls a bar with a diameter of 88mm; the second stage rolls a bar with a diameter of 74mm; the third stage rolls a bar with a diameter of 65mm; and the fourth stage rolls a non-magnetic wear-resistant nickel-chromium alloy bar with a diameter of 32.8mm.

[0041] The obtained non-magnetic wear-resistant nickel-chromium alloy, as tested, comprises the following components by mass percentage: C: 0.03%, Mn: 0.04%, Si: 0.02%, Cr: 40.5%, Al: 3%, Ti: 1.05%, S: 0.01%, P: 0.01%, and the balance Ni and unavoidable impurities.

[0042] Example 3

[0043] This embodiment provides a method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, comprising the following steps:

[0044] Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 80 min, add aluminum plate and titanium block, melt at 1540℃ for 90 min when the vacuum degree is 3 Pa, and obtain Φ250mm electrode blank.

[0045] Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as the slag material, wherein the mass ratio of each component is CaF2:Al2O3:CaO:MgO=6:1.9:1:1, the slag material is heated to a molten state and poured into the electroslag furnace crystallizer. The electrode billet is inserted into the composite slag material, and electricity is applied. The current is 8kA and the voltage is 35V. Electroslag remelting is performed at a constant melting rate of 3.5kg / min. The resulting molten steel droplets pass through the molten slag layer, and the electroslag remelted into an electroslag ingot with a diameter of 365mm.

[0046] Step 3: Heat the electroslag ingot to 1150℃ and hold for 4 hours. Perform three-stage forging, keeping the forging temperature at 1150℃-1160℃. The first forging yields a Φ255mm forging billet; the second forging yields a Φ210mm forging billet; and the third forging yields a Φ160mm intermediate billet.

[0047] Step 4: After polishing the surface of the intermediate billet, heat it to 1170℃ and hold it for 3 hours. Then, perform four-stage rolling, keeping the temperature of the intermediate billet at 1150-1160℃. The first stage rolls a bar with a diameter of 88mm; the second stage rolls a bar with a diameter of 74mm; the third stage rolls a bar with a diameter of 65mm; and the fourth stage rolls a non-magnetic wear-resistant nickel-chromium alloy bar with a diameter of 38mm.

[0048] The obtained non-magnetic wear-resistant nickel-chromium alloy, as tested, comprises the following components by mass percentage: C: 0.01%, Mn: 0.03%, Si: 0.04%, Cr: 39.5%, Al: 3%, Ti: 1.05%, S: 0.01%, P: 0.01%, and the balance Ni and unavoidable impurities.

[0049] Example 4

[0050] This embodiment provides a method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, comprising the following steps:

[0051] Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 80 min, add aluminum plate and titanium block, melt at 1540℃ for 80 min when the vacuum degree is 3 Pa, and obtain Φ250mm electrode blank.

[0052] Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as the slag material, wherein the mass ratio of each component is CaF2:Al2O3:CaO:MgO = 5.8:2.1:0.9:1, the slag material is heated to a molten state and poured into an electroslag furnace crystallizer. The electrode billet is inserted into the composite slag material, and electricity is applied. The current is 10kA and the voltage is 38V. Electroslag remelting is performed at a constant melting rate of 3.4kg / min. The resulting molten steel droplets pass through the molten slag layer, and the electroslag remelted into an electroslag ingot with a diameter of 360mm.

[0053] Step 3: Heat the electroslag ingot to 1150℃ and hold for 4 hours. Perform three-stage forging, keeping the forging temperature at 1150℃-1160℃. The first forging yields a Φ255mm forging billet; the second forging yields a Φ210mm forging billet; and the third forging yields a Φ160mm intermediate billet.

[0054] Step 4: After polishing the surface of the intermediate billet, heat it to 1170℃ and hold it for 3 hours. Then, perform four-stage rolling, keeping the temperature of the intermediate billet at 1150-1160℃. The first stage rolls a bar with a diameter of 88mm; the second stage rolls a bar with a diameter of 74mm; the third stage rolls a bar with a diameter of 65mm; and the fourth stage rolls a non-magnetic wear-resistant nickel-chromium alloy bar with a diameter of 36mm.

[0055] Tests have shown that the non-magnetic wear-resistant nickel-chromium alloy comprises the following components by mass percentage: C: 0.03%, Mn: 0.05%, Si: 0.02%, Cr: 40.2%, Al: 3%, Ti: 1.05%, S: 0.01%, P: 0.01%, and the balance Ni and unavoidable impurities.

[0056] Example 5

[0057] This embodiment provides a method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, comprising the following steps:

[0058] Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 80 min, add aluminum plate and titanium block, melt at 1540℃ for 90 min when the vacuum degree is 3 Pa, and obtain Φ250mm electrode blank.

[0059] Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as the slag material, wherein the mass ratio of each component is CaF2:Al2O3:CaO:MgO = 4.8:2.5:1.5:1, the slag material is heated to a molten state and poured into an electroslag furnace crystallizer. The electrode billet is inserted into the composite slag material, and an electric current of 8kA and a voltage of 35V are applied. Electroslag remelting is performed at a constant melting rate of 3.3kg / min. The resulting molten steel droplets pass through the molten slag layer, and the electroslag remelted into an electroslag ingot with a diameter of 360mm.

[0060] Step 3: Heat the electroslag ingot to 1150℃ and hold for 4 hours. Perform three-stage forging, keeping the forging temperature at 1150℃-1160℃. The first forging yields a Φ255mm forging billet; the second forging yields a Φ210mm forging billet; and the third forging yields a Φ160mm intermediate billet.

[0061] Step 4: After smoothing the surface of the intermediate billet, heat it to 1170℃ and hold it for 3 hours. Then, perform four-stage rolling, keeping the temperature of the intermediate billet at 1150-1160℃. The first stage rolls a bar with a diameter of 88mm; the second stage rolls a bar with a diameter of 74mm; the third stage rolls a bar with a diameter of 65mm; and the fourth stage rolls a non-magnetic wear-resistant nickel-chromium alloy bar with a diameter of 32.8mm.

[0062] The obtained non-magnetic wear-resistant nickel-chromium alloy, as tested, comprises the following components by mass percentage: C: 0.03%, Mn: 0.08%, Si: 0.05%, Cr: 40.7%, Al: 3%, Ti: 1.05%, S: 0.01%, P: 0.01%, and the balance Ni and unavoidable impurities.

[0063] Comparative Example 1

[0064] This comparative example provides a method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, which differs from Example 1 in that the melting rate is 4.0 kg / min, and includes the following steps:

[0065] Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 80 min, add aluminum plate and titanium block, melt at 1540℃ for 90 min when the vacuum degree is 3 Pa, and obtain Φ250mm electrode blank.

[0066] Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as the slag material, wherein the mass ratio of each component is CaF2:Al2O3:CaO:MgO=6:2:1:1, the slag material is heated to a molten state and poured into the electroslag furnace crystallizer. The electrode billet is inserted into the composite slag material, and electricity is applied. The current is 8kA and the voltage is 35V. Electroslag remelting is performed at a constant melting rate of 4.0kg / min. The resulting molten steel droplets pass through the molten slag layer, and the electroslag remelted into an electroslag ingot with a diameter of 360mm.

[0067] Step 3: Heat the electroslag ingot to 1150℃ and hold for 4 hours. Perform three-stage forging, maintaining the forging temperature at 1150℃-1160℃. The first forging yields a Φ250mm forging billet; the second forging yields a Φ200mm forging billet; and the third forging yields a Φ150mm intermediate billet.

[0068] Step 4: After smoothing the surface of the intermediate billet, heat it to 1160℃ and hold it for 3 hours. Then, perform four-stage rolling, keeping the intermediate billet temperature at 1150-1160℃. The first stage rolls a bar with a diameter of 88.7mm; the second stage rolls a bar with a diameter of 70.5mm; the third stage rolls a bar with a diameter of 62.4mm; and the fourth stage rolls a non-magnetic wear-resistant nickel-chromium alloy bar with a diameter of 38mm.

[0069] The obtained non-magnetic wear-resistant nickel-chromium alloy, as tested, comprises the following components by mass percentage: C: 0.04%, Mn: 0.13%, Si: 0.1%, Cr: 38.6%, Al: 3.05%, Ti: 1.05%, S: 0.01%, P: 0.01%, and the balance Ni and unavoidable impurities.

[0070] Comparative Example 2

[0071] This comparative example provides a non-magnetic wear-resistant nickel-chromium alloy, which is smelted using a vacuum consumable metallurgy method, including the following steps:

[0072] The non-magnetic wear-resistant nickel-chromium alloy comprises the following components in weight percentage: C: 0.02%, Mn: 0.13%, Si: 0.1%, Cr: 40%, Al: 3.05%, Ti: 1.05%, S: 0.01%, P: 0.01%, and the balance Ni;

[0073] Step 1: According to the design ratio, put C, Ni, Mn, Si and Cr into the crucible of the vacuum induction furnace, melt and refine for 80 min, add Al and Ti, and melt at 1540℃ for 90 min when the vacuum degree is 3 Pa to obtain an electrode blank with Φ250mm.

[0074] Step 2: Polish the surface of the electrode blank, and send the electrode blank into a vacuum consumable furnace under high vacuum (i.e., vacuum degree ≤ 1 Pa) for consumable smelting to obtain a Φ300mm consumable ingot.

[0075] Step 3: Heat the consumable ingot to 1150℃ and hold for 4 hours. Perform three-stage forging, maintaining the forging temperature at 1150℃-1160℃. The first forging yields a Φ250mm forging billet; the second forging yields a Φ200mm forging billet; and the third forging yields a Φ150mm intermediate billet.

[0076] Step 4: After smoothing the surface of the intermediate billet, heat it to 1160℃ and hold it for 3 hours. Then, perform four-stage rolling, keeping the intermediate billet temperature at 1150-1160℃. The first stage rolls a bar with a diameter of 88.7mm; the second stage rolls a bar with a diameter of 70.5mm; the third stage rolls a bar with a diameter of 62.4mm; and the fourth stage rolls a non-magnetic wear-resistant nickel-chromium alloy bar with a diameter of 38mm.

[0077] The obtained non-magnetic wear-resistant nickel-chromium alloy, as tested, comprises the following components by mass percentage: C: 0.04%, Mn: 0.09%, Si: 0.1%, Cr: 39.26%, Al: 2.71%, Ti: 0.88%, S: 0.01%, P: 0.01%, and the balance Ni and unavoidable impurities.

[0078] To further demonstrate the technical effects of the present invention, the nickel-chromium alloys obtained in the various embodiments and comparative examples were tested as follows:

[0079] GB / T10561-2005 Determination of Non-metallic Inclusions in Steel - Standard Rating Chart Microscopic Examination Method. The test results are shown in Table 1.

[0080] GB / T4162-2008 Ultrasonic testing method for forged and rolled steel bars and test of yield; the test results are shown in Table 2.

[0081] Table 1 Results of Inclusion Measurement

[0082] project Oxide grade Point-like non-deformable inclusion grade Example 1 0.5 0.5 Example 2 0.5 0.5 Example 3 0.5 0.5 Example 4 0.5 0.5 Example 5 1.0 1.0 Comparative Example 1 1.0 1.5 Comparative Example 2 1.0 1.0

[0083] As can be seen from Table 1, the oxide grade and the dot-shaped non-deformable inclusion grade of the non-magnetic wear-resistant nickel-chromium alloys provided in Examples 1-4 of the present invention both meet the 0.5 grade, while the oxide grade and the dot-shaped non-deformable inclusion grade of the non-magnetic wear-resistant nickel-chromium alloys provided in Comparative Examples 1-2 meet the 1.0 grade. This also shows that the inclusion content in the non-magnetic wear-resistant nickel-chromium alloys provided in Examples 1-4 of the present invention is low.

[0084] Table 2 Detection Results

[0085] project yield Quality grade Example 1 76.8％ AAA Example 2 75.4％ AAA Example 3 75.5％ AAA Example 4 75.4％ AAA Example 5 55.2％ A Comparative Example 1 58.8％ A Comparative Example 2 32.1％ A

[0086] As can be seen from Table 2, the non-magnetic wear-resistant nickel-chromium alloys provided in Examples 1-4 of this invention have a high yield, reaching up to 76.8%, which meets the requirements of AAA-grade products. In contrast, the nickel-chromium alloy prepared by vacuum consumable method in Comparative Example 2 has a yield of only 32.1%, which only meets the requirements of Grade A products, far lower than the nickel-chromium alloy prepared by electroslag remelting in this application. This also confirms that the non-magnetic wear-resistant nickel-chromium alloy prepared by electroslag remelting in this invention has superior performance, a higher yield, and does not produce lumps during the preparation process, thus avoiding safety issues. It effectively solves the technical problems of severe lumps, difficulty in forming consumable ingots, high inclusion content, severe fracture during hot working, and extremely low yield of nickel-chromium alloys in the prior art.

[0087] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for smelting a non-magnetic, wear-resistant nickel-chromium alloy, characterized in that: Includes the following steps: Step 1: Put graphite, nickel plate and chromium plate into the crucible of vacuum induction furnace, melt and refine for 60min-90min, add aluminum plate and titanium block, melt at 1500℃-1560℃ when the vacuum degree is ≤5Pa to obtain electrode blank. Step 2: Under an inert atmosphere, using a quaternary slag system of CaF2-Al2O3-CaO-MgO as slag material, heat the slag material to melt and pour it into the electroslag furnace crystallizer. Insert the electrode billet into the molten slag material, apply electricity, and perform constant melting rate electroslag remelting at a melting rate of 3.0 kg / min-3.5 kg / min. The resulting molten steel droplets pass through the molten slag layer and solidify into electroslag ingots with a diameter of Φ350 mm-Φ370 mm. Step 3: Heat the electroslag ingot to 1120℃-1170℃, hold for 3h-6h, and forge to obtain an intermediate billet; Step 4: After grinding the surface of the intermediate billet, heat it to 1120℃-1170℃, hold it for 2h-4h, and roll it to obtain the non-magnetic wear-resistant nickel-chromium alloy; the non-magnetic wear-resistant nickel-chromium alloy comprises the following components by mass percentage: C: 0.01%-0.02%, Cr: 39%-41%, Al: 2.75%-3.15%, Ti: 0.9%-1.15%, Mn≤0.05%, Si≤0.05%, S≤0.02%, P≤0.02%, and the balance Ni and unavoidable impurities; The mass ratio of each component in the quaternary slag system is CaF2:Al2O3:CaO:MgO = 5-6:1-3:0.8-1:0.8-1.

2. The smelting method of the non-magnetic wear-resistant nickel-chromium alloy as described in claim 1, characterized in that: In step one, the refining temperature is 1500-1560℃; and / or In step one, the melting time is 60-90 minutes.

3. The smelting method of the non-magnetic wear-resistant nickel-chromium alloy as described in claim 1, characterized in that: In step two, the current applied is 6kA-12kA, and the voltage applied is 20V-45V.

4. The smelting method of the non-magnetic wear-resistant nickel-chromium alloy as described in claim 1, characterized in that: In step three, the forging is a three-stage forging process, with a forging temperature of 1150℃-1160℃; and / or In step four, the rolling process is a four-segment rolling process with a rolling temperature of 1140℃-1170℃.

5. The smelting method of the non-magnetic wear-resistant nickel-chromium alloy as described in claim 4, characterized in that: In the three-stage forging process, the first stage forging produces a forging blank with a diameter of Φ250mm-Φ260mm; the second stage forging produces a forging blank with a diameter of Φ200mm-Φ210mm; and the third stage forging produces an intermediate blank with a diameter of Φ150mm-Φ160mm.

6. The smelting method of the non-magnetic wear-resistant nickel-chromium alloy as described in claim 4, characterized in that: In the four-stage rolling process, the first stage produces bars with a diameter of 85mm-90mm; the second stage produces bars with a diameter of 65mm-85mm; the third stage produces bars with a diameter of 55mm-65mm; and the fourth stage produces bars with a diameter of ≤40mm.

7. A non-magnetic, wear-resistant nickel-chromium alloy, characterized in that: It is prepared by the smelting method of the non-magnetic wear-resistant nickel-chromium alloy according to any one of claims 1-6.

8. The application of the non-magnetic, wear-resistant nickel-chromium alloy of claim 7 in transmission components.