Production process of wear-resistant and corrosion-resistant hardfacing alloy welding wire

Abstract

The application provides a wear-resistant and corrosion-resistant hard-facing alloy welding wire production process. The wear-resistant and corrosion-resistant hard-facing alloy welding wire production process comprises the following steps: S1: precise multi-element micro-alloy proportioning and pretreatment, adopting multi-element compound proportioning of main wear-resistant elements, auxiliary corrosion-resistant elements and refining elements, and selecting high chromium, molybdenum and tungsten as the main wear-resistant elements. The wear-resistant and corrosion-resistant hard-facing alloy welding wire production process provided by the application realizes reasonable cost control, improves the performance of the welding wire by optimizing the proportioning of raw materials, improving the utilization rate of alloy elements and the qualified rate of finished products, reasonably controls the production cost, enhances the market competitiveness of the product, is suitable for a wide range of applications, can be used for surfacing repair and surface strengthening of various substrates, covers multiple downstream industries, and is mature in process, low in equipment investment cost, does not need large-scale modification of the existing production line, is easy to realize large-scale popularization, and promotes the technical upgrading and industrial development of the hard-facing alloy welding wire industry.

Description

Technical Field

[0001] This invention relates to the field of alloy welding wire production technology, and in particular to the production process of wear-resistant and corrosion-resistant hardface alloy welding wire. Background Technology

[0002] Alloy welding wire is a welding consumable made by adding various alloying elements such as chromium, nickel, manganese, silicon, and molybdenum to ordinary carbon steel or alloy steel as the base material. It is mostly in the form of coiled wire. It fills the weld by melting with an electric arc and can be used for welding different base materials such as carbon steel, stainless steel, and alloy steel. Compared with ordinary carbon steel welding wire, alloy welding wire has stronger high temperature resistance, corrosion resistance, wear resistance and high strength. It can improve the weld microstructure and reduce cracks and porosity defects. It is widely used in industrial welding scenarios such as machinery manufacturing, pressure vessels, pipeline engineering and heavy equipment.

[0003] The production of wear-resistant and corrosion-resistant hard alloy welding wire involves designing alloy formulas such as chromium, nickel, molybdenum, and tungsten according to working conditions. High-purity raw materials are smelted in an electric furnace, refined, and deoxidized to form alloy ingots or steel strips, which are then rolled, drawn, or filled with flux and precision wound into coils. The entire process strictly controls the uniformity of composition and the stability of structure to ensure that the welding wire can form a hardened layer with high hardness, strong wear resistance, and resistance to acid and alkali corrosion after welding. It is suitable for surface strengthening and repair in heavy-duty corrosive working conditions such as mining, metallurgy, and chemical industries.

[0004] Traditional hard alloy welding wire production has many shortcomings. Rough control of alloy ratios can easily lead to component segregation, resulting in uneven wear and corrosion resistance of the product, making it difficult to meet the requirements of extreme working conditions such as mining machinery and offshore wind power. It also has a short service life and increases maintenance costs. Production lacks anti-oxidation measures, alloy elements are severely burned and impurities are easily introduced, poor adhesion between the outer sheath and the core can easily cause forming defects, improper process parameters can lead to deterioration of internal structure and properties, lack of surface protection makes it easy to rust, and limited testing methods make it difficult to guarantee overall quality.

[0005] Therefore, it is necessary to provide a production process for wear-resistant and corrosion-resistant hardface alloy welding wire to solve the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides a production process for wear-resistant and corrosion-resistant hard alloy welding wire, which solves the problems of traditional hard alloy welding wire production, such as crude formulation, easy oxidation and defects, insufficient process and protection, imperfect testing, and difficulty in adapting to harsh working conditions.

[0007] To solve the above-mentioned technical problems, the present invention provides a manufacturing process for wear-resistant and corrosion-resistant hardface alloy welding wire, which includes the following steps:

[0008] S1: Precise proportioning and pretreatment of multi-element microalloys. A multi-element composite proportioning of main wear-resistant elements, auxiliary corrosion-resistant elements, and refining elements is adopted. The core components are selected as high chromium, molybdenum, and tungsten as main wear-resistant elements, and nickel and copper as auxiliary corrosion-resistant elements. Trace amounts of vanadium, boron, and rare earth element cerium are added as elements for microstructure refinement and performance regulation. The proportioning error of each element is strictly controlled within the specified range. In the pretreatment stage, all alloy raw materials are dried at low temperature to remove moisture and oil stains from the surface of the raw materials. Then, the block alloy raw materials are crushed to the specified mesh size powder using a mechanical crushing process. Impurities and unqualified particles are removed by air classification screening to ensure that the purity of the raw materials meets the specified standards and to avoid the introduction of impurities that lead to the degradation of welding wire performance.

[0009] S2: Low-temperature pre-melting under an inert atmosphere. The screening of multi-element alloy powder is placed in a special sealed furnace, argon gas is introduced to purge the air in the furnace, the pressure in the furnace is controlled to be maintained within a specified range, the temperature is raised to a specified temperature and held for a specified time. During this period, low-frequency stirring is used to ensure that the alloying elements are fully diffused and uniformly mixed to form a pre-melted alloy powder with uniform composition. After the pre-melting is completed, the temperature is slowly lowered to room temperature to prevent rapid cooling from causing powder agglomeration or compositional stratification, thus laying the foundation for subsequent molding.

[0010] S3: Composite outer skin layer forming and tight bonding. The composite outer skin layer forming process is adopted. Low carbon steel is selected as the outer skin base material. First, the base material is rolled into a steel strip with uniform thickness. The steel strip is pre-bent into a U-shaped groove through a special mold. Then, pre-melted alloy powder is evenly filled into the U-shaped groove. The filling density is controlled within the specified range to avoid voids or uneven filling. Next, a secondary rolling process is adopted to gradually roll the edge of the U-shaped groove to form a circular cross section. The rolling pressure is gradually increased in three levels to ensure that the outer skin and the core are tightly bonded. The bonding gap is controlled within the specified range. Finally, preliminary drawing is performed to draw the welding wire diameter to the preliminary specification to reduce core displacement during subsequent drawing.

[0011] S4: Multi-pass low-temperature drawing and annealing combined. The drawing process is divided into specified passes, and the deformation of each pass is controlled within a specified range to avoid excessive deformation in a single pass, which could lead to cracking of the outer skin. The drawing temperature is controlled within a specified range. Low-temperature drawing reduces alloy oxidation and grain growth. After every 3 passes of drawing, a low-temperature annealing treatment is performed. The annealing temperature is controlled within a specified range, and the wire is held at the specified temperature for a specified time. Then, the wire is slowly cooled to room temperature to eliminate the internal stress generated during the drawing process, refine the grains, and make the internal structure of the welding wire more uniform and dense. Finally, through multi-pass drawing, the welding wire is drawn to the target diameter, ensuring that the diameter tolerance and surface roughness are controlled within the specified range.

[0012] S5: Low-temperature tempering and surface passivation under an inert atmosphere. To further improve the wear resistance and corrosion resistance of the welding wire and eliminate residual stress, low-temperature tempering and surface passivation under an inert atmosphere are added. The drawn welding wire is placed in a sealed tempering furnace, protected by argon gas, heated to a specified temperature, held for a specified time, and slowly cooled to room temperature. Low-temperature tempering stabilizes the internal structure of the welding wire, reduces deformation and cracking tendency during welding, and improves the toughness and hardness of the welding wire. After tempering, surface passivation is performed by immersing the welding wire in a low-concentration chromate passivation solution for a specified time to form a uniform and dense passivation film on the surface of the welding wire, isolating it from air and moisture, reducing the risk of oxidation and corrosion during storage and use, and improving the arc stability during welding.

[0013] S6: Segmented Precision Inspection and Screening. This process is implemented throughout the entire production process. First, raw material inspection: spectral analysis is used to detect the alloy powder composition, ensuring the proportions meet requirements. Second, pre-melted powder inspection: the uniformity of the pre-melted powder composition is observed using a metallographic microscope; unqualified powder is re-melted. Third, forming inspection: an outer diameter measuring instrument and ultrasonic flaw detector are used to inspect the welding wire diameter and internal defects, rejecting products with excessive diameter deviations, internal pores, or cracks. Fourth, finished product inspection: a hardness tester, corrosion test, and wear test are used to inspect the finished product performance, while also checking the integrity of the surface passivation film; unqualified finished products are reworked to ensure the finished product pass rate meets the specified standards.

[0014] Preferably, in S1, the proportions of high chromium are 18%–28%, molybdenum is 2%–4%, tungsten is 3%–6%, nickel is 2%–5%, copper is 1%–2%, vanadium is 0.5%–1%, boron is 0.001%–0.005%, and rare earth cerium is 0.05%–0.1%. The proportions of each element are controlled within ±0.05%. The raw materials are dried at a low temperature of 120℃–150℃ for 2–3 hours. The block alloy raw materials are crushed to a mesh size of 100–120 mesh, and the purity of the raw materials after screening is not less than 99.8%.

[0015] Preferably, the purity of the S2 argon gas is not less than 99.99%, the pressure inside the sealed furnace is 0.12-0.15 MPa, the pre-melting temperature is 800℃-850℃, the holding time is 1.5-2h, the low-frequency stirring speed is 50-80 r / min, and the cooling rate after pre-melting is controlled at 50℃ / h.

[0016] Preferably, in S3, the low-carbon steel has a carbon content of no more than 0.15%, the steel strip thickness is 0.8–1.2 mm, and the core filling density is 1.8–2.0 g / cm³. 3The three-stage rolling pressure is 5-8 MPa, 10-12 MPa, and 15-18 MPa respectively. The gap between the outer skin and the flux core is no more than 0.02 mm. After the initial drawing, the diameter of the welding wire is 3-4 mm. In S3, there are 8-10 drawing passes, with a drawing deformation of 8%-12% per pass. The drawing temperature is 150℃-200℃, the low-temperature annealing temperature is 550℃-600℃, and the holding time is 1 hour. The final target diameter of the welding wire is 1.2-2.0 mm, the diameter tolerance is no more than ±0.01 mm, and the surface roughness Ra is no more than 0.8 μm.

[0017] Preferably, in step S5, the oxygen content in the tempering furnace is no more than 0.005%, the tempering temperature is 300℃~350℃, the holding time is 2~2.5h, the concentration of chromate passivation solution is 2%~3%, the passivation immersion time is 10~15min, and the passivation film thickness is 0.5~1μm. In step S6, the hardness of the finished product is no less than HRC60, the neutral salt spray test duration is no less than 1000h, the abrasive wear is no more than 0.05g / cm², and the finished product qualification rate is no less than 99.5%.

[0018] Preferably, the sealed furnace used in S2 includes: a mounting base;

[0019] A heating furnace is mounted on top of a mounting base. A temperature control device is mounted on top of the mounting base. A sealing assembly is mounted on top of the heating furnace. Two sealing valves are mounted on top of the sealing assembly. A gas inlet pipe and a raw material inlet pipe are respectively mounted on top of the two sealing valves. A discharge assembly is mounted on the bottom of the heating furnace.

[0020] A drive structure is mounted on top of a sealing assembly, and a stirring assembly is mounted on the output end of the drive structure. Two sets of cleaning components are mounted on the outer surface of the stirring assembly.

[0021] The mounting base provides stable support for the entire device, ensuring stable operation of all components and preventing pre-fusion accuracy from being affected by device shaking. This lays the foundation for improving the core performance of the welding wire. The heating furnace, as a core component, utilizes a combination of its outer sealed protective wall, inner insulation plate, heating structure, and metal inner wall to prevent heat loss, stabilize the low-temperature pre-melting environment, prevent oxidation and burn-off of alloying elements, avoid impurities, and ensure the purity of the pre-melted powder. The temperature control equipment precisely regulates the heating temperature, preventing powder agglomeration and component segregation caused by temperature fluctuations, ensuring stable pre-melting results. The sealing valve and sealing components work together to achieve furnace... The entire furnace is fully sealed to prevent inert gas leakage and air infiltration, thus preventing the oxidation of alloying elements. The gas inlet pipe and raw material inlet pipe ensure smooth delivery of gas and raw materials. The sealing structure ensures no leakage and no impurities from entering. The drive structure provides stable driving force for the stirring and cleaning components. The stirring component achieves uniform mixing of powder, the cleaning component cleans the furnace wall to prevent powder adhesion, and the discharge component smoothly discharges materials to avoid residual pollution, ensuring continuous production. The top of the sealing component is equipped with a pressure relief structure, which can expel internal air while argon is injected. This pressure relief structure ensures the sealing of the heating furnace when closed.

[0022] Preferably, a control box with a door is installed on the top of the mounting base, and an operation panel is installed on one side of the control box. The heating furnace includes a sealed protective outer wall, an inner insulation board, a heating structure, and a metal inner wall.

[0023] Preferably, the sealing assembly includes a top cover, a sealing ring, and a connecting buckle, wherein the sealing ring is installed at the bottom of the top cover, and the connecting buckle is installed on the outer surface of the top cover;

[0024] The connecting buckle is used to fasten the top cover to the top of the heating furnace, and the sealing ring is inserted into the interior of the heating furnace.

[0025] Preferably, the stirring assembly includes a rotating shaft, multiple mounting rings, and multiple sets of tilting blades. The multiple mounting rings are used to mount the multiple sets of tilting blades on the outer surface of the rotating shaft. The cleaning assembly includes multiple connecting rods and cleaning rings. The multiple connecting rods are used to mount the cleaning rings on the outer surface of the rotating shaft.

[0026] Preferably, the discharge assembly includes a discharge valve and a discharge pipe, the discharge valve being used to install the discharge pipe at the outlet of the heating furnace.

[0027] Compared with related technologies, the wear-resistant and corrosion-resistant hardface alloy welding wire production process provided by this invention has the following beneficial effects:

[0028] This invention provides a production process for wear-resistant and corrosion-resistant hardface alloy welding wire. This process significantly improves the dual core properties of the welding wire: wear resistance and corrosion resistance. Through precise proportioning and microstructure optimization of multi-element microalloying, it can effectively adapt to extreme working conditions such as mining, power, and offshore wind power, significantly extending the service life of welded components, reducing the frequency of equipment maintenance and operating costs in downstream industries, and improving the quality stability and finished product qualification rate of the welding wire. Through inert atmosphere protection, segmented precision testing, and other full-process quality control measures, it effectively inhibits the oxidation and burning loss of alloy elements and component segregation, reduces internal defects in the welding wire, reduces rework and waste of defective products, improves production efficiency, enhances welding performance and reliability, and optimizes the bonding design of the composite sheath and flux core, reducing defects such as porosity, slag inclusions, and cracks during welding. This technology reduces the incidence of corrosion, improves the bonding strength between the weld overlay and the substrate, ensures stable and reliable welding quality, extends the storage and service life of the welding wire, and effectively isolates corrosive media such as air and moisture, reducing oxidation and rust loss during storage. It also simplifies pre-treatment procedures before welding, improves welding efficiency, and achieves reasonable cost control. By optimizing raw material ratios, improving alloy element utilization and finished product qualification rates, it significantly improves welding wire performance while reasonably controlling production costs, enhancing product market competitiveness. With a wide range of applications, it can be used for weld overlay repair and surface strengthening of various substrates, covering multiple downstream industries. Furthermore, the technology is mature, equipment investment costs are low, and there is no need for large-scale modifications to existing production lines, making it easy to achieve large-scale promotion and driving technological upgrading and industrial development in the hard alloy welding wire industry. Attached Figure Description

[0029] Figure 1 A schematic diagram of the first embodiment of the production process of wear-resistant and corrosion-resistant hardface alloy welding wire provided by the present invention;

[0030] Figure 2 A schematic diagram of the structure of a second embodiment of the production process of wear-resistant and corrosion-resistant hardface alloy welding wire provided by the present invention;

[0031] Figure 3 A schematic diagram of the installation structure is provided for this invention;

[0032] Figure 4 Provided for the present invention Figure 3 An enlarged view of point A shown;

[0033] Figure 5 Provided for the present invention Figure 3 An enlarged view of point B shown;

[0034] Figure 6 Provided for the present invention Figure 3 A magnified view of point C shown.

[0035] The diagram is labeled as follows: 1. Mounting base, 2. Control box, 3. Box door, 4. Operation panel, 5. Temperature control equipment, 6. Heating furnace, 601. Sealed protective outer wall, 602. Inner insulation board, 603. Heating structure, 604. Metal inner wall, 7. Sealing valve, 8. Sealing assembly, 801. Top cover, 802. Sealing ring, 803. Connecting buckle, 9. Gas inlet pipe, 10. Drive structure, 11. Raw material inlet pipe, 12. Discharge assembly, 121. Discharge valve, 122. Discharge pipe, 13. Stirring assembly, 131. Rotating shaft, 132. Mounting ring, 133. Inclined blade, 14. Cleaning assembly, 141. Connecting rod, 142. Cleaning ring. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] First Embodiment

[0038] Please refer to the following: Figure 1 ,in, Figure 1 This is a schematic diagram of a first embodiment of the production process for the wear-resistant and corrosion-resistant hardface alloy welding wire provided by the present invention. The production process for the wear-resistant and corrosion-resistant hardface alloy welding wire includes the following steps:

[0039] S1: Precise proportioning and pretreatment of multi-element microalloys. A multi-element composite proportioning of main wear-resistant elements, auxiliary corrosion-resistant elements, and refining elements is adopted. The core components are selected as high chromium, molybdenum, and tungsten as main wear-resistant elements, and nickel and copper as auxiliary corrosion-resistant elements. Trace amounts of vanadium, boron, and rare earth element cerium are added as elements for microstructure refinement and performance regulation. The proportioning error of each element is strictly controlled within the specified range. In the pretreatment stage, all alloy raw materials are dried at low temperature to remove moisture and oil stains from the surface of the raw materials. Then, the block alloy raw materials are crushed to the specified mesh size powder using a mechanical crushing process. Impurities and unqualified particles are removed by air classification screening to ensure that the purity of the raw materials meets the specified standards and to avoid the introduction of impurities that lead to the degradation of welding wire performance.

[0040] S2: Low-temperature pre-melting under an inert atmosphere. The screening of multi-element alloy powder is placed in a special sealed furnace, argon gas is introduced to purge the air in the furnace, the pressure in the furnace is controlled to be maintained within a specified range, the temperature is raised to a specified temperature and held for a specified time. During this period, low-frequency stirring is used to ensure that the alloying elements are fully diffused and uniformly mixed to form a pre-melted alloy powder with uniform composition. After the pre-melting is completed, the temperature is slowly lowered to room temperature to prevent rapid cooling from causing powder agglomeration or compositional stratification, thus laying the foundation for subsequent molding.

[0041] S3: Composite outer skin layer forming and tight bonding. The composite outer skin layer forming process is adopted. Low carbon steel is selected as the outer skin base material. First, the base material is rolled into a steel strip with uniform thickness. The steel strip is pre-bent into a U-shaped groove through a special mold. Then, pre-melted alloy powder is evenly filled into the U-shaped groove. The filling density is controlled within the specified range to avoid voids or uneven filling. Next, a secondary rolling process is adopted to gradually roll the edge of the U-shaped groove to form a circular cross section. The rolling pressure is gradually increased in three levels to ensure that the outer skin and the core are tightly bonded. The bonding gap is controlled within the specified range. Finally, preliminary drawing is performed to draw the welding wire diameter to the preliminary specification to reduce core displacement during subsequent drawing.

[0042] S4: Multi-pass low-temperature drawing and annealing combined. The drawing process is divided into specified passes, and the deformation of each pass is controlled within a specified range to avoid excessive deformation in a single pass, which could lead to cracking of the outer skin. The drawing temperature is controlled within a specified range. Low-temperature drawing reduces alloy oxidation and grain growth. After every 3 passes of drawing, a low-temperature annealing treatment is performed. The annealing temperature is controlled within a specified range, and the wire is held at the specified temperature for a specified time. Then, the wire is slowly cooled to room temperature to eliminate the internal stress generated during the drawing process, refine the grains, and make the internal structure of the welding wire more uniform and dense. Finally, through multi-pass drawing, the welding wire is drawn to the target diameter, ensuring that the diameter tolerance and surface roughness are controlled within the specified range.

[0043] S5: Low-temperature tempering and surface passivation under an inert atmosphere. To further improve the wear resistance and corrosion resistance of the welding wire and eliminate residual stress, low-temperature tempering and surface passivation under an inert atmosphere are added. The drawn welding wire is placed in a sealed tempering furnace, protected by argon gas, heated to a specified temperature, held for a specified time, and slowly cooled to room temperature. Low-temperature tempering stabilizes the internal structure of the welding wire, reduces deformation and cracking tendency during welding, and improves the toughness and hardness of the welding wire. After tempering, surface passivation is performed by immersing the welding wire in a low-concentration chromate passivation solution for a specified time to form a uniform and dense passivation film on the surface of the welding wire, isolating it from air and moisture, reducing the risk of oxidation and corrosion during storage and use, and improving the arc stability during welding.

[0044] S6: Segmented Precision Inspection and Screening. This process is implemented throughout the entire production process. First, raw material inspection: spectral analysis is used to detect the alloy powder composition, ensuring the proportions meet requirements. Second, pre-melted powder inspection: the uniformity of the pre-melted powder composition is observed using a metallographic microscope; unqualified powder is re-melted. Third, forming inspection: an outer diameter measuring instrument and ultrasonic flaw detector are used to inspect the welding wire diameter and internal defects, rejecting products with excessive diameter deviations, internal pores, or cracks. Fourth, finished product inspection: a hardness tester, corrosion test, and wear test are used to inspect the finished product performance, while also checking the integrity of the surface passivation film; unqualified finished products are reworked to ensure the finished product pass rate meets the specified standards.

[0045] S1 requires strict control of the proportioning error of each element during mixing. Pre-treatment low-temperature drying necessitates controlled temperature and holding time. After pulverization, the powder must undergo airflow classification screening to ensure it is free of impurities and has uniform particle size, preventing impurities from affecting the welding wire performance. S2 pre-fusion requires high-purity argon gas to completely purge air from the furnace. Strict control of furnace pressure, heating temperature, and holding time is crucial. Low-frequency stirring and a gradual cooling rate are necessary to prevent powder agglomeration or component stratification. S3 uses low-carbon steel as the outer sheath substrate, with uniform steel strip thickness. The powder filling the U-shaped groove must have uniform density. Rolling is also required. The pressure is gradually increased in three levels to ensure a tight fit between the outer sheath and the core. The initial drawing requires control of the diameter specifications. The S4 drawing requires a specified number of passes, controlling the deformation and drawing temperature per pass. After every three passes, low-temperature annealing is required, with strict control over the annealing temperature and holding time. The S5 tempering requires the introduction of argon gas for protection. The passivation treatment requires control over the concentration of the passivation solution and the soaking time to ensure a uniform and dense passivation film. The S6 inspection must be carried out throughout the entire process, with each inspection step requiring the use of corresponding specialized equipment. Non-conforming products must be reworked or reprocessed in a timely manner to ensure that each step meets the prescribed standards.

[0046] The S1 alloy contains 18%–28% high chromium, 2%–4% molybdenum, 3%–6% tungsten, 2%–5% nickel, 1%–2% copper, 0.5%–1% vanadium, 0.001%–0.005% boron, and 0.05%–0.1% rare earth cerium. The ratio of each element is controlled within ±0.05%. The raw materials are dried at a low temperature of 120℃–150℃ for 2–3 hours. The block alloy raw materials are crushed to a mesh size of 100–120 mesh, and the purity of the raw materials after screening is not less than 99.8%.

[0047] The purity of S2 argon gas is not less than 99.99%, the pressure inside the sealed furnace is 0.12~0.15MPa, the pre-melting temperature is 800℃~850℃, the holding time is 1.5~2h, the low-frequency stirring speed is 50~80r / min, and the cooling rate after pre-melting is controlled at 50℃ / h.

[0048] S3 low-carbon steel has a carbon content of no more than 0.15%, a strip thickness of 0.8–1.2 mm, and a core filling density of 1.8–2.0 g / cm³. 3 The three rolling pressures are 5-8 MPa, 10-12 MPa, and 15-18 MPa respectively. The gap between the outer skin and the flux core is no more than 0.02 mm. The diameter of the welding wire after the initial drawing is 3-4 mm. There are 8-10 drawing passes in S3, with a drawing deformation of 8%-12% per pass. The drawing temperature is 150℃-200℃, the low-temperature annealing temperature is 550℃-600℃, and the holding time is 1 hour. The final target diameter of the welding wire is 1.2-2.0 mm, the diameter tolerance is no more than ±0.01 mm, and the surface roughness Ra is no more than 0.8 μm.

[0049] In S5, the oxygen content in the tempering furnace is no more than 0.005%, the tempering temperature is 300℃~350℃, the holding time is 2~2.5h, the concentration of chromate passivation solution is 2%~3%, the passivation immersion time is 10~15min, and the passivation film thickness is 0.5~1μm. In S6, the hardness of the finished product is no less than HRC60, the neutral salt spray test time is no less than 1000h, the abrasive wear is no more than 0.05g / cm², and the finished product qualification rate is no less than 99.5%.

[0050] The working principle of the wear-resistant and corrosion-resistant hardface alloy welding wire production process provided by this invention is as follows:

[0051] This process achieves precise control of alloying elements, refined and dense microstructure, tight interface bonding, and comprehensive performance enhancement through multi-stage process optimization. It also effectively inhibits oxidation corrosion, ensuring stable welding wire quality. In the multi-element microalloying stage, high-chromium, molybdenum, and tungsten serve as the main wear-resistant elements, forming high-hardness carbides during welding, significantly improving the wear resistance of the weld overlay. Nickel and copper, as auxiliary corrosion-resistant elements, enhance the passivation ability of the weld overlay and improve corrosion resistance. Vanadium, boron, and rare earth elements act as heterogeneous nucleation sites, effectively refining grains and inhibiting columnar crystal growth, while improving the alloy's toughness and crack resistance. Precise control of the element ratios achieves a balance between hardness, toughness, and corrosion resistance. In the pretreatment stage, low-temperature drying removes surface moisture and oil from the raw materials. Mechanical crushing and air classification ensure the purity and uniform particle size of the raw materials, preventing impurities and large particles from affecting subsequent processes. Low-temperature pre-fusion under an inert atmosphere utilizes the inert properties of argon. Isolating the air prevents alloying elements from reacting with oxygen and causing oxidation and burn-off. Low-frequency stirring at low temperatures promotes full diffusion of elements, preventing component segregation and providing a uniform raw material base for subsequent forming. Layered composite sheath forming, through pre-bending, filling, and graded rolling, enhances the bond between the sheath and the core, preventing core displacement and sheath cracking. Multi-pass low-temperature drawing, by controlling the deformation amount and drawing temperature per pass, prevents grain growth and sheath cracking. Low-temperature annealing between passes eliminates internal stress and refines grains, resulting in a uniform and dense welding wire structure. Low-temperature tempering in an inert atmosphere stabilizes the microstructure and eliminates residual stress. Surface passivation treatment forms a dense passivation film, isolating corrosive media and inhibiting oxidation and corrosion. Segmented precision testing comprehensively controls quality at each stage, promptly eliminating defective products and ensuring the reliability of welding applications. This comprehensive process addresses the pain points of traditional processes, significantly improving welding wire performance.

[0052] Compared with related technologies, the wear-resistant and corrosion-resistant hardface alloy welding wire production process provided by this invention has the following beneficial effects:

[0053] This process significantly enhances the dual core properties of welding wire: wear resistance and corrosion resistance. Through precise multi-element microalloying and optimized microstructure, it effectively adapts to extreme working conditions in mining, power, and offshore wind power, significantly extending the service life of welded components, reducing equipment maintenance frequency and operating costs in downstream industries, and improving the quality stability and finished product qualification rate of welding wire. Through inert atmosphere protection, segmented precision testing, and other full-process quality control measures, it effectively inhibits the oxidation and burning loss of alloying elements and component segregation, reducing internal defects in the welding wire, minimizing rework and waste of defective products, improving production efficiency, enhancing welding performance and reliability, and optimizing the bonding design between the composite sheath and the flux core. This reduces the incidence of defects such as porosity, slag inclusions, and cracks during welding, improving the bonding between the weld overlay and the substrate. The bonding strength of the materials ensures stable and reliable welding quality, extends the storage and service life of the welding wire, and the surface passivation film can effectively isolate corrosive media such as air and moisture, reducing oxidation and rust loss during storage. At the same time, it simplifies the pre-treatment process before welding, improves welding efficiency, and achieves reasonable cost control. By optimizing the raw material ratio, improving the utilization rate of alloy elements and the finished product qualification rate, the performance of the welding wire is significantly improved while reasonably controlling the production cost, enhancing the market competitiveness of the product. It has a wide range of applications and can be used for surfacing repair and surface strengthening of various substrates, covering multiple downstream industries. Moreover, the process is mature, the equipment investment cost is low, and there is no need for large-scale transformation of existing production lines, making it easy to achieve large-scale promotion and drive the technological upgrading and industrial development of the hard alloy welding wire industry.

[0054] Second Embodiment

[0055] Please refer to the following: Figures 2-3 - Figures 4-5 - Figure 6 , Figure 2 A schematic diagram of the structure of a second embodiment of the production process of wear-resistant and corrosion-resistant hardface alloy welding wire provided by the present invention; Figure 3 A schematic diagram of the installation structure is provided for this invention; Figure 4 Provided for the present invention Figure 3 An enlarged view of point A shown; Figure 5 Provided for the present invention Figure 3 An enlarged view of point B shown; Figure 6 Provided for the present invention Figure 3 The enlarged view at point C shows a production process for wear-resistant and corrosion-resistant hardface alloy welding wire based on the first embodiment of this application. The second embodiment of this application proposes another production process for wear-resistant and corrosion-resistant hardface alloy welding wire. The second embodiment is merely a preferred embodiment of the first embodiment, and its implementation will not affect the independent implementation of the first embodiment.

[0056] Specifically, the difference in the production process of wear-resistant and corrosion-resistant hard alloy welding wire provided in the second embodiment of this application is that the sealed furnace used in S2 includes: mounting base 1;

[0057] Heating furnace 6 is installed on the top of mounting base 1. Temperature control device 5 is installed on the top of mounting base 1. Sealing assembly 8 is installed on the top of heating furnace 6. Two sealing valves 7 are installed on the top of sealing assembly 8. Gas inlet pipe 9 and raw material inlet pipe 11 are installed on the top of the two sealing valves 7 respectively. Discharge assembly 12 is installed at the bottom of heating furnace 6.

[0058] The drive structure 10 is installed on top of the sealing assembly 8. The output end of the drive structure 10 is equipped with a stirring assembly 13. Two sets of cleaning assemblies 14 are installed on the outer surface of the stirring assembly 13.

[0059] The mounting base 1 provides stable support for the entire device, ensuring stable operation of all components and preventing pre-fusion accuracy from being affected by device shaking. This lays the foundation for improving the core performance of the welding wire. The heating furnace 6, as a core component, with its outer 601 sealed protective wall, 602 inner insulation plate, 603 heating structure, and 604 metal inner wall working together, blocks heat loss, stabilizes the low-temperature pre-melting environment, prevents oxidation and burn-off of alloying elements, avoids impurity contamination, and ensures the purity of the pre-melted powder. The temperature control device 5 precisely regulates the heating temperature, preventing powder agglomeration and component segregation caused by temperature fluctuations, ensuring stable pre-melting results. The sealing valve 7, in conjunction with the sealing assembly 8, achieves furnace... The entire furnace is fully sealed to prevent inert gas leakage and air infiltration, thus preventing the oxidation of alloying elements. The gas inlet pipe 9 and the raw material inlet pipe 11 smoothly transport gas and raw materials. The sealing structure ensures no leakage and no impurities from entering. The drive structure 10 provides a stable driving force for the stirring component 13 and the cleaning component 14. The stirring component 13 achieves uniform mixing of powder, the cleaning component 14 cleans the furnace wall to prevent powder from sticking, and the discharge component 12 smoothly discharges materials to avoid residual pollution, ensuring continuous production. The top of the sealing component 8 is equipped with a pressure relief structure, which can discharge internal air while argon is injected. This pressure relief structure ensures the airtightness of the heating furnace 6 when closed.

[0060] Please refer to Figure 2 and Figure 3 The top of the mounting base 1 is equipped with a control box 2 with a door 3, and an operation panel 4 is installed on one side of the control box 2. The heating furnace 6 includes a sealed protective outer wall 601, an inner insulation board 602, a heating structure 603, and a metal inner wall 604.

[0061] The operation panel 4 allows for setting equipment operating parameters. The control box 2 contains a power switch and a controller for auxiliary equipment operation. The sealed protective outer wall 601 is made of Q235 low-carbon steel plate, 8-10mm thick, which has moderate mechanical strength, low cost, and is easy to process and form. It effectively protects the internal insulation and heating structures and serves as the installation base for the sealing structure, enhancing the overall rigidity of the furnace body, preventing deformation, ensuring stable sealing performance, and preventing argon leakage. The inner insulation board 602 is made of high-temperature resistant ceramic fiber board, 50-60mm thick, with excellent high-temperature resistance. It can withstand a low pre-melting temperature of 800-850℃, has a low thermal conductivity, and can effectively block the heat from being conducted outward from the furnace, thus stabilizing the low-temperature pre-melting environment inside the furnace. The heating structure uses nickel-chromium alloy heating wire made of 603 material, which is 2-3mm thick and wrapped inside the insulation board. It has high resistance and uniform heating, which can stably generate heat and precisely control the temperature inside the furnace, avoiding local overheating. It is also corrosion-resistant and high-temperature resistant. The metal inner wall is made of 304 stainless steel plate made of 604 material, which is 5-6mm thick. It is corrosion-resistant and high-temperature resistant, can prevent impurities from entering, has a smooth surface for easy cleaning, and has high mechanical strength to support the operation of the components.

[0062] Please refer to Figure 3 and Figure 4 The sealing assembly 8 includes a top cover 801, a sealing ring 802, and a connecting buckle 803. The sealing ring 802 is installed at the bottom of the top cover 801, and the connecting buckle 803 is installed on the outer surface of the top cover 801.

[0063] The connecting buckle 803 is used to fasten the top cover 801 to the top of the heating furnace 6, and the sealing ring 802 is inserted into the interior of the heating furnace 6.

[0064] Please refer to Figure 3 and Figure 5 The stirring assembly 13 includes a rotating shaft 131, multiple mounting rings 132, and multiple sets of tilting blades 133. The multiple mounting rings 132 are used to mount the multiple sets of tilting blades 133 on the outer surface of the rotating shaft 131. The cleaning assembly 14 includes multiple connecting rods 141 and cleaning rings 142. The multiple connecting rods 141 are used to mount the cleaning rings 142 on the outer surface of the rotating shaft 131.

[0065] The tilting blade 133 adopts an inclined design with a blade tilt angle of 15°-25°. It is made of high-temperature and wear-resistant alloy with a thickness of 2-3mm and a polished surface to avoid scratching the inner metal wall. At the same time, the blade spacing is evenly set to ensure that the powder can be stirred in all directions without any dead corners, avoiding uneven mixing of local powders. The tilting blade 133 is firmly connected to the rotating shaft 131 to prevent it from falling off during stirring and to ensure stable stirring effect. The cleaning ring 142 is made of wear-resistant material, and the outer surface of the cleaning ring 142 is in contact with the inner surface of the heating furnace 6.

[0066] Please refer to Figure 3 and Figure 6 The discharge assembly 12 includes a discharge valve 121 and a discharge pipe 122. The discharge valve 121 is used to install the discharge pipe 122 at the outlet of the heating furnace 6.

[0067] The discharge valve 121 is a high-temperature resistant and well-sealed valve.

[0068] Compared with related technologies, the wear-resistant and corrosion-resistant hardface alloy welding wire production process provided by this invention has the following beneficial effects:

[0069] To ensure uniform mixing of multi-element alloy powders during low-temperature pre-fusion in an inert atmosphere, prevent component segregation and oxidation loss, and improve the component uniformity, wear resistance, and corrosion resistance of the alloy powder, raw materials are fed into the heating furnace 6 through raw material inlet pipe 11. Simultaneously, inert gas is introduced through gas inlet pipe 9. Both raw material inlet pipe 11 and gas inlet pipe 9 are assisted by sealing valve 7 to facilitate the smooth entry of inert gas and raw materials while preventing leakage. Sealing assembly 8 is installed on the top of the heating furnace 6 to achieve a seal at the top of the furnace body, in conjunction with sealing valve 7. The furnace body is sealed in all directions to prevent gas leakage and air infiltration. The heating furnace 6, as the core component, consists of, from the outside in, a sealed protective outer wall 601, an inner insulation plate 602, a heating structure 603, and a metal inner wall 604. The temperature control device 5 controls the heating structure 603 of the heating furnace 6 to heat the furnace, while precisely controlling the heating temperature. Together with the sealed protective outer wall 601, the inner insulation plate 602, and the metal inner wall 604, a stable low-temperature pre-melting environment is maintained. The drive structure 10 provides power to the stirring assembly 13 and the cleaning assembly 14. The rotating drive force and cleaning component 14 are installed on the outer surface of the rotating shaft 131 of the stirring component 13. Its cleaning ring 142 is in close contact with the metal inner wall 604 of the heating furnace 6, achieving a real-time cleaning effect and preventing metal powder from sticking together. The stirring component 13 stirs the powder through the rotating shaft 131, the mounting ring 132 and the tilting blade 133 to achieve uniform mixing of multi-element alloy powder. The discharge component 12 is installed at the bottom of the heating furnace 6. It is controlled by the discharge valve 121 and transported by the discharge pipe 122 to achieve smooth discharge of powder after pre-melting, avoiding residue and secondary pollution. During operation, the sealing structure ensures the purity of the inert atmosphere and prevents the oxidation of alloy elements. The temperature control and heating structure ensures temperature stability. The stirring and cleaning components prevent component segregation and material sticking. The coordinated operation of each structure forms a complete pre-melting process with significant effects. It can ensure the purity and uniformity of pre-melted powder, reduce material loss, prevent impurities from mixing in, ensure production continuity, provide high-quality raw material support for the wear resistance and corrosion resistance of welding wire, improve production efficiency, ensure the stability of subsequent welding wire production processes, and help achieve core performance standards.

[0070] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A manufacturing process for wear-resistant and corrosion-resistant hard alloy welding wire, characterized in that, Includes the following steps: S1: Precise proportioning and pretreatment of multi-element microalloys. A multi-element composite proportioning of main wear-resistant elements, auxiliary corrosion-resistant elements, and refining elements is adopted. The core components are selected as high chromium, molybdenum, and tungsten as main wear-resistant elements, and nickel and copper as auxiliary corrosion-resistant elements. Trace amounts of vanadium, boron, and rare earth element cerium are added as elements for microstructure refinement and performance regulation. The proportioning error of each element is strictly controlled within the specified range. In the pretreatment stage, all alloy raw materials are dried at low temperature to remove moisture and oil stains from the surface of the raw materials. Then, the block alloy raw materials are crushed to the specified mesh size powder using a mechanical crushing process. Impurities and unqualified particles are removed by air classification screening to ensure that the purity of the raw materials meets the specified standards and to avoid the introduction of impurities that lead to the degradation of welding wire performance. S2: Low-temperature pre-melting under an inert atmosphere. The screening of multi-element alloy powder is placed in a special sealed furnace, argon gas is introduced to purge the air in the furnace, the pressure in the furnace is controlled to be maintained within a specified range, the temperature is raised to a specified temperature and held for a specified time. During this period, low-frequency stirring is used to ensure that the alloying elements are fully diffused and uniformly mixed to form a pre-melted alloy powder with uniform composition. After the pre-melting is completed, the temperature is slowly lowered to room temperature to prevent rapid cooling from causing powder agglomeration or compositional stratification, thus laying the foundation for subsequent molding. S3: Composite outer skin layer forming and tight bonding. The composite outer skin layer forming process is adopted. Low carbon steel is selected as the outer skin base material. First, the base material is rolled into a steel strip with uniform thickness. The steel strip is pre-bent into a U-shaped groove through a special mold. Then, pre-melted alloy powder is evenly filled into the U-shaped groove. The filling density is controlled within the specified range to avoid voids or uneven filling. Next, a secondary rolling process is adopted to gradually roll the edge of the U-shaped groove to form a circular cross section. The rolling pressure is gradually increased in three levels to ensure that the outer skin and the core are tightly bonded. The bonding gap is controlled within the specified range. Finally, preliminary drawing is performed to draw the welding wire diameter to the preliminary specification to reduce core displacement during subsequent drawing. S4: Multi-pass low-temperature drawing and annealing combined. The drawing process is divided into specified passes, and the deformation of each pass is controlled within a specified range to avoid excessive deformation in a single pass, which could lead to cracking of the outer skin. The drawing temperature is controlled within a specified range. Low-temperature drawing reduces alloy oxidation and grain growth. After every 3 passes of drawing, a low-temperature annealing treatment is performed. The annealing temperature is controlled within a specified range, and the wire is held at the specified temperature for a specified time. Then, the wire is slowly cooled to room temperature to eliminate the internal stress generated during the drawing process, refine the grains, and make the internal structure of the welding wire more uniform and dense. Finally, through multi-pass drawing, the welding wire is drawn to the target diameter, ensuring that the diameter tolerance and surface roughness are controlled within the specified range. S5: Low-temperature tempering and surface passivation under an inert atmosphere. To further improve the wear resistance and corrosion resistance of the welding wire and eliminate residual stress, low-temperature tempering and surface passivation under an inert atmosphere are added. The drawn welding wire is placed in a sealed tempering furnace, protected by argon gas, heated to a specified temperature, held for a specified time, and slowly cooled to room temperature. Low-temperature tempering stabilizes the internal structure of the welding wire, reduces deformation and cracking tendency during welding, and improves the toughness and hardness of the welding wire. After tempering, surface passivation is performed by immersing the welding wire in a low-concentration chromate passivation solution for a specified time to form a uniform and dense passivation film on the surface of the welding wire, isolating it from air and moisture, reducing the risk of oxidation and corrosion during storage and use, and improving the arc stability during welding. S6: Segmented Precision Inspection and Screening. This process is implemented throughout the entire production process. First, raw material inspection: spectral analysis is used to detect the alloy powder composition, ensuring the proportions meet requirements. Second, pre-melted powder inspection: the uniformity of the pre-melted powder composition is observed using a metallographic microscope; unqualified powder is re-melted. Third, forming inspection: an outer diameter measuring instrument and ultrasonic flaw detector are used to inspect the welding wire diameter and internal defects, rejecting products with excessive diameter deviations, internal pores, or cracks. Fourth, finished product inspection: a hardness tester, corrosion test, and wear test are used to inspect the finished product performance, while also checking the integrity of the surface passivation film; unqualified finished products are reworked to ensure the finished product pass rate meets the specified standards.

2. The production process of wear-resistant and corrosion-resistant hard alloy welding wire according to claim 1, characterized in that, The S1 composition consists of 18%–28% high chromium, 2%–4% molybdenum, 3%–6% tungsten, 2%–5% nickel, 1%–2% copper, 0.5%–1% vanadium, 0.001%–0.005% boron, and 0.05%–0.1% rare earth cerium. The ratio error of each element is controlled within ±0.05%. The raw materials are dried at a low temperature of 120℃–150℃ for 2–3 hours. The block alloy raw materials are crushed to a mesh size of 100–120 mesh, and the purity of the raw materials after screening is not less than 99.8%.

3. The production process of wear-resistant and corrosion-resistant hard alloy welding wire according to claim 1, characterized in that, The purity of the S2 argon gas is not less than 99.99%, the pressure inside the sealed furnace is 0.12-0.15 MPa, the pre-melting temperature is 800℃-850℃, the holding time is 1.5-2h, the low-frequency stirring speed is 50-80 r / min, and the cooling rate after pre-melting is controlled at 50℃ / h.

4. The production process of wear-resistant and corrosion-resistant hard alloy welding wire according to claim 1, characterized in that, The S3 steel has a low carbon content of no more than 0.15%, a strip thickness of 0.8–1.2 mm, and a core filling density of 1.8–2.0 g / cm³. 3 The three-stage rolling pressure is 5-8 MPa, 10-12 MPa, and 15-18 MPa respectively. The gap between the outer skin and the flux core is no more than 0.02 mm. After the initial drawing, the diameter of the welding wire is 3-4 mm. In S3, there are 8-10 drawing passes, with a drawing deformation of 8%-12% per pass. The drawing temperature is 150℃-200℃, the low-temperature annealing temperature is 550℃-600℃, and the holding time is 1 hour. The final target diameter of the welding wire is 1.2-2.0 mm, the diameter tolerance is no more than ±0.01 mm, and the surface roughness Ra is no more than 0.8 μm.

5. The production process of wear-resistant and corrosion-resistant hardface alloy welding wire according to claim 1, characterized in that, In S5, the oxygen content in the tempering furnace is no more than 0.005%, the tempering temperature is 300℃~350℃, the holding time is 2~2.5h, the concentration of chromate passivation solution is 2%~3%, the passivation immersion time is 10~15min, and the passivation film thickness is 0.5~1μm. In S6, the hardness of the finished product is no less than HRC60, the neutral salt spray test duration is no less than 1000h, the abrasive wear is no more than 0.05g / cm², and the finished product qualification rate is no less than 99.5%.

6. The production process of wear-resistant and corrosion-resistant hardface alloy welding wire according to claim 1, wherein the sealed furnace used in step S2 is characterized in that, include: Install the base frame; A heating furnace is mounted on top of a mounting base. A temperature control device is mounted on top of the mounting base. A sealing assembly is mounted on top of the heating furnace. Two sealing valves are mounted on top of the sealing assembly. A gas inlet pipe and a raw material inlet pipe are respectively mounted on top of the two sealing valves. A discharge assembly is mounted on the bottom of the heating furnace. A drive structure is mounted on top of a sealing assembly, and a stirring assembly is mounted on the output end of the drive structure. Two sets of cleaning components are mounted on the outer surface of the stirring assembly.

7. The production process of wear-resistant and corrosion-resistant hardface alloy welding wire according to claim 1, characterized in that, The top of the mounting base is equipped with a control box with a door, and an operation panel is installed on one side of the control box. The heating furnace includes a sealed protective outer wall, an inner insulation board, a heating structure, and a metal inner wall.

8. The production process of wear-resistant and corrosion-resistant hard alloy welding wire according to claim 6, characterized in that, The sealing assembly includes a top cover, a sealing ring, and a connecting buckle. The sealing ring is installed at the bottom of the top cover, and the connecting buckle is installed on the outer surface of the top cover.

9. The production process of wear-resistant and corrosion-resistant hard alloy welding wire according to claim 6, characterized in that, The stirring assembly includes a rotating shaft, multiple mounting rings, and multiple sets of tilting blades. The multiple mounting rings are used to mount the multiple sets of tilting blades on the outer surface of the rotating shaft. The cleaning assembly includes multiple connecting rods and cleaning rings. The multiple connecting rods are used to mount the cleaning rings on the outer surface of the rotating shaft.

10. The production process of wear-resistant and corrosion-resistant hard alloy welding wire according to claim 6, characterized in that, The discharge assembly includes a discharge valve and a discharge pipe, the discharge valve being used to install the discharge pipe at the outlet of the heating furnace.

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