Shield hob ring and remanufacturing method thereof

Abstract

The invention relates to the technical field of shield tunneling machines, and particularly discloses a shield hobbing cutter ring and a remanufacturing method thereof. According to the method, the iron-based alloy powder serves as a main body, the modified powder is added as an auxiliary, the remanufactured alloy powder is obtained, the alloy deposition layer is formed on the surface of the cutter ring body through the remanufactured alloy powder, and remanufacturing machining of the shield hob cutter ring is completed. Under the synergistic effect of the components of the modified powder, the alloy deposition layer can have good hardness and wear resistance, the defects of iron-based self-fluxing alloy are overcome, the defects of the remanufactured and repaired cutter ring in the tunneling process are reduced, and various extreme service conditions can be fully dealt with.

Description

Technical Field

[0001] This application relates to the field of tunnel boring machine technology, and more specifically, it relates to a tunnel boring machine cutterhead ring and a method for remanufacturing the same. Background Technology

[0002] Tunnel boring machines (TBMs) are essential infrastructure equipment widely used for tunnel excavation. The cutterhead rings are a critical component of the TBM, frequently subjected to extreme operating conditions such as immense pressure, bending, torsion, impact, wear, and localized high temperatures. Consequently, after a period of use, they may fail due to wear, fracture, spalling, or deformation. When a TBM cutterhead ring fails, it often needs to be replaced to continue construction. This process is not only time-consuming, but the replaced cutterhead rings are also difficult to reuse, resulting in significant resource waste.

[0003] Given this situation, remanufacturing technology offers a relatively ideal solution. One commonly used remanufacturing technique is welding, which primarily increases hardness by forming a wear-resistant alloy layer (such as high-chromium cast iron or cobalt-based alloys) on the surface of the cutter ring. However, welding involves significant heat input, easily causing cracks in already aged cutter rings, and it's difficult to ensure a tight bond between the remanufactured cladding layer and the cutter ring body, thus still having certain limitations. Besides welding, the rapidly developing new technology of laser cladding 3D printing in recent years has also provided a new approach to the remanufacturing of tunnel boring machine cutter rings. Laser cladding 3D printing uses a high-energy laser beam to clad metal-based composite materials, forming a dense cladding layer on the surface of the cutter ring body, thereby achieving the regeneration of damaged parts. It is currently the most promising technology.

[0004] Regarding the aforementioned technologies, the inventors believe that although laser cladding 3D printing can remanufacture the cutter rings of tunnel boring machines, the hardness and wear resistance of the iron-based self-fluxing alloys currently used for laser cladding 3D printing are limited. The remanufactured and repaired cutter rings are still prone to damage during tunnel excavation, requiring frequent maintenance and making it difficult to fully cope with the various extreme service conditions faced by tunnel boring machines. Summary of the Invention

[0005] In related technologies, iron-based self-fluxing alloys lack sufficient hardness and wear resistance, making it difficult to adequately cope with the various extreme service conditions faced by tunnel boring machines. To improve this deficiency, this application provides a tunnel boring machine cutterhead ring and its remanufacturing method.

[0006] Firstly, this application provides a shield tunneling cutterhead ring, which adopts the following technical solution: A tunnel boring machine cutterhead ring, comprising a cutterhead body and an alloy deposition layer, wherein the alloy deposition layer is disposed on the outer surface of the cutterhead body, and the alloy deposition layer is formed by laser cladding of remanufactured alloy powder, wherein the remanufactured alloy powder comprises the following components in parts by weight: 73-80 parts of iron-based alloy powder and 15-22 parts of modified powder; wherein the modified powder comprises silicon nitride powder, zirconium boride powder and titanium-based mixed powder, and the titanium-based mixed powder comprises titanium powder and boron carbide powder.

[0007] By adopting the above technical solution, this application uses iron-based alloy powder as the main body and adds modified powder as an auxiliary to obtain remanufactured alloy powder. The remanufactured alloy powder is then used to form an alloy deposition layer on the surface of the cutterhead body, completing the remanufacturing process of the tunnel boring machine cutterhead. In the modified powder, silicon nitride powder and zirconium boride powder, as added hard ceramic phases, can increase the non-uniform nucleation during the molten pool cooling process. Elements precipitated after the decomposition of unmelted silicon nitride powder and zirconium boride powder hinder grain growth, resulting in a reduction in grain size in the alloy deposition layer, thus playing a role in grain refinement and strengthening. The addition of reinforcing phases and the new phases generated by decomposition produce solid solution strengthening. Meanwhile, titanium powder and boron carbide powder can react during laser cladding, generating titanium boride and titanium carbide ceramic phases in situ. These in-situ generated ceramic phases interact in the alloy deposition layer to form dispersion strengthening, and also increase the deformation resistance and grain slip resistance of the alloy deposition layer, making the grain refinement strengthening effect of silicon nitride powder and zirconium boride powder more stable. Furthermore, the titanium boride produced during the zirconium boride and laser cladding processes synergistically promotes the transformation of silicon nitride from the α-phase to the β-phase, thereby generating a toughening effect and helping to reduce cracking during the formation of the cladding layer. Under the synergistic effect of the various components of the modified powder, different strengthening mechanisms such as fine grain strengthening, dispersion strengthening, and solid solution strengthening can be generated in the alloy deposition layer, which significantly improves the hardness and wear resistance of the alloy deposition layer, overcomes the defects of iron-based self-fluxing alloys, and reduces the damage to the remanufactured and repaired cutterhead during tunnel excavation. Therefore, frequent maintenance of the cutterhead is not required, and it can fully cope with various extreme service conditions faced by the tunnel boring machine.

[0008] Preferably, the weight ratio of boron carbide powder to titanium powder is (1.2-1.3):3.

[0009] By adopting the above technical solution, this application has optimized the weight ratio of boron carbide powder to titanium powder, which enables the titanium powder and boron carbide to react fully, thus helping to maintain the high hardness and high wear resistance of the alloy deposited layer.

[0010] Preferably, the titanium-based mixed powder also includes cerium dioxide.

[0011] By employing the above technical solution, cerium, with its large atomic radius, can distort the surrounding crystal lattice, thus enhancing solid solution strengthening. Cerium dioxide at grain boundaries can pin and drag them, synergistically hindering grain growth along with elements precipitated from the decomposition of unmelted silicon nitride and zirconium boride powders. This increases the nucleation rate, promotes grain refinement, and ultimately increases the amount of hard phases with a more uniform distribution, significantly improving the hardness and wear resistance of the alloy deposition layer.

[0012] Preferably, the weight ratio of cerium dioxide to titanium powder is (0.2-0.5):3.

[0013] By adopting the above technical solution, this application optimizes the weight ratio of cerium dioxide to titanium powder, which helps to fully improve the hardness and wear resistance of the alloy deposited layer.

[0014] Preferably, the iron-based alloy powder includes FeNiCrBSi alloy powder.

[0015] By adopting the above technical solution, the FeNiCrBSi alloy powder contains a certain amount of chromium. Chromium is an effective solid solution strengthening element. Through synergistic cooperation with the modified powder, it can effectively enhance the solid solution strengthening effect in the alloy deposition layer, which helps to maintain the high hardness and high wear resistance of the alloy deposition layer.

[0016] Preferably, the iron-based alloy powder further includes Fe-VC iron-based alloy powder, which is prepared according to the following method: Reduced iron powder, ferrovanadium, graphite, cobalt powder, chromium powder, and molybdenum powder are mixed and ball-milled to obtain ball milling material. The ball milling material is then sieved to obtain Fe-VC iron-based alloy powder.

[0017] By adopting the above technical solution, this application preferably uses Fe-VC iron-based alloy powder as the second component of the iron-based alloy powder. Vanadium is introduced into the Fe-VC iron-based alloy powder. Vanadium is a strong carbide-forming element. During the laser cladding process, it can generate high-hardness vanadium carbides. It can also work synergistically with external hard ceramics such as silicon nitride powder and zirconium boride powder to refine the microstructure and grain size, which helps to enhance the hardness and wear resistance of the alloy deposition layer.

[0018] Preferably, the ball mill contains 3-5 wt% cobalt powder.

[0019] By adopting the above technical solution, this application optimizes the cobalt content of Fe-VC iron-based alloy powder. Cobalt can form a stable solid solution with iron and promote the uniform distribution of carbides. It can synergistically achieve good solid solution strengthening and dispersion strengthening effects with the modified powder. At the same time, the addition of cobalt also has a certain strengthening effect on the martensite in the iron-based alloy powder. Within the cobalt content range specified in this application, the alloy deposited layer can maintain good strength and wear resistance.

[0020] Preferably, the ball mill contains 2.5-3.5 wt% molybdenum powder.

[0021] By employing the above-mentioned technical solution, molybdenum can interact with boron and carbon to precipitate high-melting-point molybdenum carbide and molybdenum boride. Within the scope defined in this application, these precipitates can increase the nucleation rate, synergistically promote the refinement of the microstructure with the modified powder, improve the hardness of the alloy deposited layer, reduce stress concentration, and overcome the adverse effects of boron on the alloy deposited layer. In addition to forming carbides and borides alone, molybdenum can also be dissolved into the crystals of vanadium carbide to form composite carbides. The composite carbides, vanadium carbides, molybdenum carbides, and other carbides are distributed in a network within the alloy deposited layer, which can act as a wear-resistant skeleton. Furthermore, the addition of cobalt promotes the uniform distribution of carbides, thus effectively improving the wear resistance of the alloy deposited layer.

[0022] Preferably, the modified powder also includes nano-molybdenum carbide.

[0023] By adopting the above technical solution, this application preferably uses nano-molybdenum carbide as a component of the modified powder. Nano-molybdenum carbide can be uniformly distributed under the action of cobalt, thereby making the network-distributed carbide wear-resistant skeleton more perfect and effectively improving the hardness and wear resistance of the alloy deposition layer.

[0024] Secondly, this application provides a method for remanufacturing the cutter ring of a tunnel boring machine, which adopts the following technical solution.

[0025] A method for remanufacturing a tunnel boring machine cutterhead ring includes the following steps: (1) Remove the failed cutter ring from the hob, clean the failed cutter ring, use wire cutting to circumferentially cut the failed cutter ring to the lowest wear position on the outer diameter, remove the worn part, turn the outer surface of the failed cutter ring to flatness, and obtain the cutter ring body for later use; (2) Using any of the above-mentioned alloy powders as raw materials, an alloy deposition layer is printed on the outer surface of the cutter ring body using a laser cladding 3D printing equipment. After printing, the remanufacturing of the shield tunnel cutter ring can be completed.

[0026] By adopting the above technical solution, this application first repaired the failed cutter ring to obtain a usable cutter ring body, and then used alloy powder as raw material for laser cladding 3D printing to realize the remanufacturing of the shield tunneling cutter ring. The shield tunneling cutter ring obtained by this method has a surface protected by an alloy deposition layer, which can fully cope with various extreme service conditions faced by shield tunneling machines due to its high hardness and high wear resistance. It is not prone to damage during tunnel excavation, and there is no need for frequent cutter ring maintenance, which has broad application prospects.

[0027] In summary, this application has the following beneficial effects: 1. This application uses iron-based alloy powder as the main component and adds modified powder as an auxiliary to obtain remanufactured alloy powder. The remanufactured alloy powder is then used to form an alloy deposition layer on the surface of the cutterhead, completing the remanufacturing process of the tunnel boring machine cutterhead. Under the synergistic effect of the modified powder components, the alloy deposition layer possesses good hardness and wear resistance, overcoming the defects of iron-based self-fluxing alloys, reducing damage to the remanufactured and repaired cutterhead during tunnel excavation, and fully coping with various extreme service conditions.

[0028] 2. In this application, cerium dioxide is preferred as a component of the titanium-based mixed powder. Cerium dioxide can synergistically inhibit grain growth with the elements precipitated after the decomposition of unmelted silicon nitride powder and zirconium boride powder, thereby increasing the nucleation rate, promoting grain refinement, and ultimately increasing the amount of hard phase and making its distribution more uniform, thus significantly improving the hardness and wear resistance of the alloy deposition layer.

[0029] 3. In this application, Fe-VC iron-based alloy powder is preferred as the second component of the iron-based alloy powder. Vanadium is introduced into the Fe-VC iron-based alloy powder. Vanadium is a strong carbide-forming element that can generate vanadium carbides with high hardness. It can also work synergistically with external hard ceramics such as silicon nitride powder and zirconium boride powder to refine the microstructure and grain size, which helps to enhance the hardness and wear resistance of the alloy deposit layer. Detailed Implementation

[0030] The present application will be further described in detail below with reference to the embodiments and comparative examples. All raw materials involved in the present application can be obtained commercially. Example

[0031] Examples 1-3 The following description uses Example 1 as an example.

[0032] Example 1 In this embodiment, the modified powder is formed by mixing silicon nitride (Si3N4) powder, zirconium boride (ZrB2) powder and titanium-based mixed powder in a weight ratio of 1:1:4. The titanium-based mixed powder consists of titanium powder and boron carbide (B4C) powder, with a weight ratio of boron carbide powder to titanium powder of 1:3.

[0033] The iron-based alloy powder selected in this embodiment is FeNiCrBSi alloy powder, with the following composition: 7.3% Ni, 12.2% Cr, 1.0% B, 2.3% Si, 2.0% Mo, 0.3% Mn, 2.0% C, 0.1% V, 1.2% W, and the balance being Fe.

[0034] This embodiment provides a shield tunneling cutterhead ring, which includes a cutterhead body and an alloy deposition layer. The cutterhead body is made of forged H13 steel with an outer diameter of 420mm. The alloy deposition layer is disposed on the outer surface of the cutterhead body and is formed by laser cladding of remanufactured alloy powder. The remanufactured alloy powder includes the following components: 80kg of iron-based alloy powder and 15kg of modified powder.

[0035] This embodiment provides a method for remanufacturing a tunnel boring machine cutterhead ring, including the following steps: (1) Remove the failed cutter ring from the hob, clean the failed cutter ring, use wire cutting to circumferentially cut the failed cutter ring to the lowest wear position on the outer diameter, remove the worn part, turn the outer surface of the failed cutter ring to flatness, and obtain the cutter ring body for later use; (2) Using remanufactured alloy powder as raw material, an alloy deposition layer is printed on the outer surface of the cutter ring body using laser cladding 3D printing equipment. The 3D printing uses a YLS-4000 fiber laser with a laser radiation wavelength of 1070-1080nm and a laser head spot diameter of 3mm. The protective gas is nitrogen or argon. The printing parameters are: overlap rate of 50% and laser defocusing amount of 13mm. The laser cladding parameters are: cladding power of 1400W, powder feeding rate of 17.8g / min, cutter ring rotation speed of 9mm / s, cladding of 42 layers, and each layer thickness of 0.75mm. After printing, the remanufacturing of the shield tunnel cutter ring can be completed.

[0036] As shown in Table 1, the main difference between Examples 1-3 is that the raw material ratios of the remanufactured alloy powder are different.

[0037] Table 1 Raw material ratios for remanufactured alloy powder sample Example 1 Example 2 Example 3 Iron-based alloy powder / kg 80 76 73 Modified powder / kg 15 19 22 Example 4 The difference between this embodiment and Embodiment 3 is that the weight ratio of boron carbide powder to titanium powder is 1.2:3.

[0038] Example 5 The difference between this embodiment and Embodiment 3 is that the weight ratio of boron carbide powder to titanium powder is 1.25:3.

[0039] Example 6 The difference between this embodiment and Embodiment 3 is that the weight ratio of boron carbide powder to titanium powder is 1.3:3.

[0040] Example 7 The difference between this embodiment and Embodiment 6 is that the titanium-based mixed powder also includes cerium dioxide, and the weight ratio of cerium dioxide to titanium powder is 0.1:3.

[0041] Example 8 The difference between this embodiment and Embodiment 7 is that the weight ratio of cerium dioxide to titanium powder is 0.2:3.

[0042] Example 9 The difference between this embodiment and Embodiment 7 is that the weight ratio of cerium dioxide to titanium powder is 0.35:3.

[0043] Example 10 The difference between this embodiment and Embodiment 7 is that the weight ratio of cerium dioxide to titanium powder is 0.5:3.

[0044] Example 11 The difference between this embodiment and Embodiment 10 is that the iron-based alloy powder also includes Fe-VC iron-based alloy powder, and the weight ratio of Fe-VC iron-based alloy powder to FeNiCrBSi alloy powder is 1:2.

[0045] In this embodiment, the average particle size of the reduced iron powder is 100 μm, the average particle size of the ferrovanadium is 30 μm, the average particle size of the graphite is 20 μm, and the average particle size of the cobalt, chromium, and molybdenum powders is 1.5 μm. The ferrovanadium is FeV50, the cobalt powder accounts for 2 wt% of the total weight of the ball milling material, the molybdenum powder accounts for 2 wt% of the total weight of the ball milling material, the chromium powder accounts for 5 wt% of the total weight of the ball milling material, the graphite accounts for 6.1 wt% of the total weight of the ball milling material, and the ferrovanadium accounts for 32 wt% of the total weight of the ball milling material. The balance is made up to 100 wt% by the reduced iron powder.

[0046] Fe-VC iron-based alloy powder was prepared according to the following method: Reduced iron powder, ferrovanadium, graphite, cobalt powder, chromium powder, and molybdenum powder were mixed and ball-milled for 2 hours to obtain ball milling material. The ball milling material was then sieved to remove agglomerates, resulting in Fe-VC iron-based alloy powder.

[0047] As shown in Table 2, the difference between Examples 11-18 is that the raw material composition of the Fe-VC iron-based alloy powder is different.

[0048] Table 2 Raw material composition of Fe-VC iron-based alloy powder Comparative Example Comparative Example 1 The difference between this comparative example and Example 1 is that the remanufactured alloy powder does not include modified powder.

[0049] Comparative Example 2 The difference between this comparative example and Example 1 is that the modified powder does not include silicon nitride powder. Comparative Example 3 The difference between this comparative example and Example 1 is that the modified powder does not include zirconium boride powder. Comparative Example 4 The difference between this comparative example and Example 1 is that the modified powder does not include titanium-based mixed powder. Performance testing methods I. Vickers Hardness The microhardness of the sample was measured from the outside to the inside along the thickest point of the cross section using a DHV-1000 digital Vickers hardness tester. Each point was measured three times and the average value was taken. The test parameters were: load 1.96N, holding time 15S. The results are shown in Table 3.

[0050] II. Wear performance Unlubricated dry sliding friction and wear tests were conducted using a CETR UMT-2 multifunctional wear tester. Silicon nitride balls with a diameter of 6 mm were used as the friction pair, and the tests were performed at room temperature. The normal load was set to 50 N, the reciprocating frequency to 5 Hz, and the wear time to 1 hour. After the test, the wear volume of the specimens was measured. Using the wear volume of Comparative Example 1 as a benchmark, the ratio between the wear volume of each embodiment and the wear volume of Comparative Example 1 was calculated and recorded as the relative wear volume. The results are shown in Table 3.

[0051] Table 3 Combining Examples 1-3 and Comparative Example 1 with Table 3, it can be seen that Examples 1-3 exhibit higher Vickers hardness and lower relative wear volume. This is because, under the synergistic effect of the modified powder components, different strengthening mechanisms such as fine-grain strengthening, dispersion strengthening, and solid solution strengthening can be generated in the alloy deposition layer, which fully improves the hardness and wear resistance of the alloy deposition layer, overcomes the defects of iron-based self-fluxing alloys, and reduces the damage to the remanufactured and repaired cutter ring during tunnel excavation. Therefore, frequent maintenance of the cutter ring is not required, and it can fully cope with various extreme service conditions faced by the tunnel boring machine. In contrast, Comparative Example 1 lacks modified powder and cannot achieve the synergistic effect of this application, resulting in poorer hardness and wear resistance.

[0052] Combining Example 1 and Comparative Examples 2-3 with Table 3, it can be seen that the hardness measured in Example 1 is higher than that in Comparative Examples 2-3, while the relative wear volume is lower. This is because silicon nitride and zirconium boride work together to strengthen the grains and improve the hardness and wear resistance of the alloy deposit through synergistic effect with the titanium-based mixed powder. However, Comparative Example 2 lacks silicon nitride and Comparative Example 3 lacks zirconium boride, so they cannot effectively exert a synergistic effect, and therefore their hardness and wear resistance are affected.

[0053] Combining Example 1 and Comparative Example 4 with Table 3, it can be seen that the hardness measured in Example 1 is higher than that in Comparative Example 4, while the relative wear volume is lower. This is because titanium powder and boron carbide powder generate titanium boride and titanium carbide ceramic phases during laser cladding, forming dispersion strengthening. This also makes the fine-grain strengthening effect of silicon nitride powder and zirconium boride powder more stable, and also produces a toughening effect by promoting the phase transformation of silicon nitride. In contrast, Comparative Example 4 lacks titanium-based mixed powder, which cannot fully exert the above effects, and it is also difficult to produce a synergistic effect with silicon nitride powder and zirconium boride powder. Therefore, both hardness and wear resistance are affected.

[0054] As can be seen from Examples 3-6 and Table 3, Examples 4-6 showed higher hardness and smaller relative wear volume. This is because Examples 4-6 slightly increased the amount of boron carbide powder, which promoted a full reaction between the boron carbide powder and titanium powder, thereby improving the hardness and wear resistance of the alloy deposit.

[0055] As can be seen from Examples 6-10 and Table 3, Examples 7-10 showed higher hardness and smaller relative wear volume. This is because cerium dioxide was added in Examples 7-10. Cerium, with its large atomic radius, can distort the surrounding crystal lattice, which helps to enhance solid solution strengthening. Cerium dioxide at grain boundaries can pin and drag the grain boundaries, and together with the elements precipitated after the decomposition of unmelted silicon nitride powder and zirconium boride powder, it hinders grain growth, increases the nucleation rate, promotes grain refinement, and ultimately increases the amount of hard phase and makes its distribution more uniform, thus significantly improving the hardness and wear resistance of the alloy deposited layer. In Examples 7-10, Examples 8-10 showed higher hardness and smaller relative wear volume, indicating that when the weight ratio of cerium dioxide to titanium powder is (0.2-0.5):3, it helps to improve the hardness and wear resistance of the alloy deposited layer.

[0056] As can be seen from Examples 10 and 11 and Table 3, the hardness measured in Example 11 is higher and the relative wear volume is smaller. This is because vanadium is introduced into the Fe-VC iron-based alloy powder. Vanadium is a strong carbide-forming element that can generate vanadium carbides with high hardness. It can also work synergistically with external hard ceramics such as silicon nitride powder and zirconium boride powder to refine the microstructure and grain size, which helps to enhance the hardness and wear resistance of the alloy deposit layer.

[0057] As can be seen from Examples 11-14 and Table 3, Examples 12-14 showed higher hardness and smaller relative wear volume, with Example 13 exhibiting the best overall performance. This indicates that within the cobalt content range specified in this application, the alloy deposition layer can maintain good strength and wear resistance.

[0058] As can be seen from Examples 13 and 15-17 and Table 3, Examples 15-17 showed higher hardness and smaller relative wear volume, while Example 16 showed the best overall performance, indicating that the alloy deposited layer can maintain good strength and wear resistance within the molybdenum content range specified in this application.

[0059] As can be seen from Examples 16 and 18 and Table 3, the hardness measured in Example 18 is higher and the relative wear volume is smaller. This is because after adding nano-molybdenum carbide, the nano-molybdenum carbide can be evenly distributed under the action of cobalt, thereby making the network-distributed carbide wear-resistant skeleton more complete, which can effectively improve the hardness and wear resistance of the alloy deposition layer.

[0060] The above embodiments are merely explanations of this application and are not intended to limit it. After reading this specification, those skilled in the art can make modifications to the embodiments of this application without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of this application.

Claims

1. A shield tunneling cutterhead ring, characterized in that, The cutter ring includes a cutter ring body and an alloy deposition layer. The alloy deposition layer is disposed on the outer surface of the cutter ring body. The alloy deposition layer is formed by laser cladding of remanufactured alloy powder. The remanufactured alloy powder includes the following components in parts by weight: 73-80 parts of iron-based alloy powder and 15-22 parts of modified powder. The modified powder includes silicon nitride powder, zirconium boride powder and titanium-based mixed powder. The titanium-based mixed powder includes titanium powder and boron carbide powder.

2. The shield tunneling cutterhead ring according to claim 1, characterized in that, The weight ratio of boron carbide powder to titanium powder is (1.2-1.3):

3.

3. The shield tunneling cutterhead ring according to claim 1, characterized in that, The titanium-based mixed powder also includes cerium dioxide.

4. The shield tunneling cutterhead ring according to claim 3, characterized in that, The weight ratio of cerium dioxide to titanium powder is (0.2-0.5):

3.

5. The shield tunneling cutterhead ring according to claim 1, characterized in that, The iron-based alloy powder includes FeNiCrBSi alloy powder.

6. The shield tunneling cutterhead ring according to claim 5, characterized in that, The iron-based alloy powder further includes Fe-VC iron-based alloy powder, which is prepared according to the following method: Reduced iron powder, ferrovanadium, graphite, cobalt powder, chromium powder, and molybdenum powder are mixed and ball-milled to obtain ball milling material. The ball milling material is then sieved to obtain Fe-VC iron-based alloy powder.

7. The shield tunneling cutterhead ring according to claim 6, characterized in that, The ball milling material contains 3-5 wt% cobalt powder.

8. The shield tunneling cutterhead ring according to claim 7, characterized in that, The ball milling material contains 2.5-3.5 wt% molybdenum powder.

9. The shield tunneling cutterhead ring according to claim 8, characterized in that, The modified powder also includes nano-molybdenum carbide.

10. A method for remanufacturing a shield tunneling cutterhead ring, characterized in that, Includes the following steps: (1) Remove the failed tool ring from the hob, clean the failed tool ring, use wire cutting to circumferentially cut the failed tool ring to the lowest wear position on the outer diameter, remove the worn part, turn the outer surface of the failed tool ring until it is flat, and obtain the tool ring body for later use; (2) Using the remanufactured alloy powder as described in any one of claims 1-9 as raw material, an alloy deposition layer is printed on the outer surface of the cutter ring body using a laser cladding 3D printing equipment. After printing, the remanufacturing of the shield tunnel cutter ring can be completed.

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