Welding rod for nickel-chromium-cobalt-molybdenum high-temperature alloy welding and preparation method thereof

Abstract

The invention provides a welding rod for nickel-chromium-cobalt-molybdenum high-temperature alloy welding and a preparation method of the welding rod, and relates to the technical field of welding materials. The welding rod for nickel-chromium-cobalt-molybdenum high-temperature alloy welding comprises a core wire and a coating, and the coating comprises, by mass, 22%-30% of rutile, 29%-38% of marble, 3.5%-5.0% of fluorite, 18%-24% of cryolite, 3.5%-5.0% of potassium titanate, 0.8%-1.5% of cobalt powder, 0.8%-1.5% of molybdenum powder, 1.5%-3.0% of ferroniobium, 0.8%-1.5% of manganese metal, 0.8%-1.5% of reduced iron powder, 0.4%-1.0% of sodium alginate, 0.8%-1.5% of sodium carbonate and 0.4%-1.0% of CMC. When the welding rod is used for carrying out submerged arc horizontal position welding on the nickel-chromium-cobalt-molybdenum high-temperature alloy, the electric arc stability is good, deslagging is good, forming is attractive, deslagging is easy, deposited metal components are stable, and the mechanical property is excellent.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of welding material, and particularly relates to a welding rod for welding of nickel-chromium-cobalt-molybdenum high-temperature alloy and a preparation method thereof. BACKGROUND

[0002] The nickel-chromium-cobalt-molybdenum high-temperature alloy is widely applied to the manufacture of key components in the fields of aerospace, energy and chemical industry and shipbuilding due to its excellent high-temperature strength, creep resistance, oxidation resistance and corrosion resistance. Welding is an indispensable key process for the forming, assembling and repairing of the core components. However, when the traditional welding rod is used for welding, various metallurgical defects are easily caused: the weld metal often has high hot crack sensitivity and serious alloy element burning loss; meanwhile, harmful phases are easily precipitated during the welding process, which leads to a significant decrease in the high-temperature mechanical properties and corrosion resistance of the weld, and it is difficult to meet the long-time service requirement under severe working conditions. SUMMARY

[0003] The present application provides a welding rod for welding of nickel-chromium-cobalt-molybdenum high-temperature alloy and a preparation method thereof, so as to improve the welding performance of the nickel-chromium-cobalt-molybdenum high-temperature alloy.

[0004] The present application provides a welding rod for welding of nickel-chromium-cobalt-molybdenum high-temperature alloy, which comprises a welding core and a coating, and the coating comprises the following components in percentage of total mass of the coating: 22-30% of rutile, 29-38% of marble, 3.5-5.0% of fluorite, 18-24% of cryolite, 3.5-5.0% of potassium titanate, 0.8-1.5% of cobalt powder, 0.8-1.5% of molybdenum powder, 1.5-3.0% of niobium iron, 0.8-1.5% of metallic manganese, 0.8-1.5% of reduced iron powder, 0.4-1.0% of sodium alginate, 0.8-1.5% of alkali, and 0.4-1.0% of CMC (sodium carboxymethyl cellulose).

[0005] In an embodiment of the present application, the mass of the coating accounts for 44-46% of the total mass of the welding rod.

[0006] In an embodiment of the present application, the welding core is NiCrCoMo-1 alloy.

[0007] In an embodiment of the present application, the mass fraction of the rutile passing through a 60-mesh sieve is 100%, and the mass fraction of the rutile passing through a 200-mesh sieve is ≤20%; the mass fraction of the marble passing through a 60-mesh sieve is ≥95%, and the mass fraction of the marble passing through a 200-mesh sieve is ≤50%; the mass fraction of the fluorite passing through an 80-mesh sieve is ≥95%; the mass fraction of the cryolite passing through a 60-mesh sieve is ≥95%; the mass fraction of the potassium titanate passing through an 80-mesh sieve is ≥95%, and the mass fraction of the potassium titanate passing through a 200-mesh sieve is ≤40%; and the mass fraction of the cobalt powder, the molybdenum powder, the niobium iron, the metallic manganese and the reduced iron powder passing through a 60-mesh sieve is ≥95%.

[0008] In one embodiment of the present application, the rutile has TiO2≥95%, the marble has CaCO3≥96%, the fluorite has CaF2≥95.0% and SiO2≤4.5%, the cryolite has Na3AlF6≥93%, the potassium titanate has TiO2≥65%, K2O+Na2O is 18~22%, Cl≤0.1%, the cobalt powder has Co≥95%, the molybdenum powder has Mo≥99.0%, the niobium iron has Nb≥65%, the metallic manganese has Mn content≥99.8%, the reduced iron powder has Fe≥98.0%, the sodium alginate has ash≤30, K2O is 13.5~18%, the PH value is 6~8, and the moisture content≤15%, and the alkali surface has Na2CO3≥98%.

[0009] The present application also provides a preparation method of the electrode for nickel-chromium-cobalt-molybdenum high-temperature alloy welding.

[0010] The components of the coating are weighed according to the proportion, mixed uniformly in a mixer to obtain coating powder; The binder is added to the coating powder and stirred uniformly to obtain coating paint; The coating paint is pressed and coated on the surface of the welding core to obtain an electrode semi-finished product; The electrode semi-finished product is dried at room temperature and then subjected to drying treatment to obtain the electrode for nickel-chromium-cobalt-molybdenum high-temperature alloy welding.

[0011] In one embodiment of the present application, the mass of the binder is 18~20% of the total mass of the coating powder.

[0012] In one embodiment of the present application, the binder is sodium silicate binder, and the modulus of the sodium silicate binder is 1:1.

[0013] In one embodiment of the present application, the pressure of the press coating when the coating paint is pressed and coated on the surface of the welding core is 8~15MPa.

[0014] In one embodiment of the present application, the drying treatment includes: first drying at 100~150℃ for 1~2h, and then drying at 300~350℃ for 1~1.5h.

[0015] The beneficial effects of the present application: the flux-cored wire for welding nickel-chromium-cobalt-molybdenum high-temperature alloy of the present application has achieved remarkable beneficial effects through the scientific proportioning and synergistic effect of various components. Specifically, the formula builds a slag system with suitable high-temperature viscosity and rapid solidification characteristics through the synergistic effect of a high proportion of rutile, marble and ice crystals. The formed slag can provide strong support to the molten pool, perfectly adapting to the requirements of full-position welding (especially horizontal welding and vertical welding) for molten pool control. At the same time, the flowability and surface tension of the slag are adjusted by fluorite and ice crystals, promoting the escape of gas and flotation of impurities during welding, effectively inhibiting the generation of pores and slag. Further, the combined deoxidation of metallic manganese and reduced iron powder in the flux, and strict control of the content of harmful impurities, together ensure smooth transition of alloying elements and pure and stable composition of weld metal, ultimately obtaining high-quality welds with compact internal quality, smooth and beautiful appearance, and extremely low defect rate. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application. It is to be expressly understood that the drawings are only for purposes of illustration and are not to be construed as limiting the application. From reading the following description, other advantages and features of the present application will become apparent.

[0017] In the drawings: Figure 1 The preparation flow chart of the flux-cored wire for welding nickel-chromium-cobalt-molybdenum high-temperature alloy provided by an embodiment of the present application. DETAILED DESCRIPTION

[0018] The embodiments of the present application will be described herein below with reference to specific embodiments. Other advantages and features of the present application will become apparent from the following description. The present application can be implemented or applied in other different embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. The following embodiments and features in the embodiments can be combined with each other without conflict.

[0019] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner, and the drawings only show the components related to the present application, not the number, shape and size of the components when actually implemented. The actual implementation of each component may be arbitrarily changed in type, number and proportion, and the layout pattern of the components may be more complex.

[0020] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0021] In this document, when referring to numerical ranges, unless otherwise specified, the distribution of selectable values ​​within a numerical range is considered continuous, including the two endpoints of the range (i.e., the minimum and maximum values), and every value between these two endpoints. When multiple numerical ranges are provided to describe a feature or property, these numerical ranges can be combined.

[0022] Currently, some welding materials have been developed for nickel-chromium-cobalt-molybdenum (NiChC-CMO) superalloys. Although their alloy composition is similar to that of the base metal, they still have shortcomings in terms of actual welding processability and the overall performance of the final weld. Therefore, how to effectively control the content of impurities such as oxygen, sulfur, and phosphorus in the weld metal while ensuring efficient and stable transition of alloying elements through precise design and optimization of the electrode coating composition, and further refine and improve the microstructure of the deposited metal, thereby comprehensively improving the room temperature and high temperature performance of the weld joint, is an important technical problem that urgently needs to be solved by those skilled in the art. Therefore, this invention provides a welding electrode for NiChC-CMO superalloys to solve the above problems.

[0023] The welding electrode provided by this invention for welding nickel-chromium-cobalt-molybdenum high-temperature alloys includes a core and a coating. The coating, by total mass, comprises the following components in the following mass percentages: rutile 22-30%, marble 29-38%, fluorite 3.5-5.0%, cryolite 18-24%, potassium titanate 3.5-5.0%, cobalt powder 0.8-1.5%, molybdenum powder 0.8-1.5%, ferroniobium 1.5-3.0%, metallic manganese 0.8-1.5%, reduced iron powder 0.8-1.5%, sodium alginate 0.4-1.0%, baking soda 0.8-1.5%, and CMC 0.4-1.0%.

[0024] The functions of each component in the coating of this invention are as follows: Rutile: It is the core arc stabilizer and slag-forming agent. Its main component, titanium dioxide, can significantly reduce the arc voltage, making the arc combustion very stable and gentle with minimal spatter. The slag it forms is "short slag," which has good coverage and is easy to remove, thus determining the electrode's processability.

[0025] Marble: It is the main gas-generating and slag-forming agent (alkaline). Marble decomposes at high temperatures to produce CO2 gas, forming a protective gas layer. The decomposed CaO combines with other substances to form alkaline slag, which can effectively desulfurize and dephosphorize, and improve weld toughness. It is one of the most important raw materials in welding electrodes.

[0026] Fluorite: Its main function is as a diluent. Its primary function is to reduce the viscosity, melting point, and surface tension of alkaline slag, increase its fluidity, ensure uniform slag coverage, improve air permeability, and facilitate slag removal.

[0027] Cryolite: As a powerful diluent and arc stabilizer, it has a stronger ability to reduce the viscosity of molten slag and a better arc stabilizing effect.

[0028] Cobalt powder, molybdenum powder, ferroniobium, and metallic manganese are used together as alloying element additives. When these metal or alloy powders are heated in the flux coating, they either melt directly or enter the weld pool through a metallurgical reaction to compensate for burn-off during the welding process or to actively impart strength and toughness to the weld.

[0029] Reduced iron powder: Serves as a supplementary iron-based metal source. Adding a large amount of iron powder to the flux coating causes the powder to melt simultaneously during welding, significantly increasing the amount of filler metal and greatly improving deposition efficiency. Improved arc characteristics: Iron powder stabilizes the arc and absorbs excess heat.

[0030] Sodium alginate and CMC: These are added as water-based binders and thickeners during the preparation of the coating material, when the powdered raw materials are mixed into a slurry. They provide good adhesion, flowability, and thixotropy, making the coating slurry easy to apply to the core and maintaining its shape and preventing cracking before drying.

[0031] Baking soda: In water-based coatings, it acts as an electrolyte to adjust the pH and viscosity of the slurry, improving the coating's suspension and application properties. The dosage must be precisely controlled; excessive amounts may have adverse effects during drying or welding.

[0032] In one embodiment of the present invention, the mass of the coating accounts for 44-46% of the total mass of the welding electrode.

[0033] In one embodiment of the present invention, the welding core is a NiCrCoMo-1 alloy.

[0034] In one embodiment of the present invention, the mass fraction of rutile passing through a 60-mesh sieve is 100%, and the mass fraction passing through a 200-mesh sieve is ≤20%; the mass fraction of marble passing through a 60-mesh sieve is ≥95%, and the mass fraction passing through a 200-mesh sieve is ≤50%; the mass fraction of fluorite passing through an 80-mesh sieve is ≥95%; the mass fraction of cryolite passing through a 60-mesh sieve is ≥95%; the mass fraction of potassium titanate passing through an 80-mesh sieve is ≥95%, and the mass fraction passing through a 200-mesh sieve is ≤40%; and the mass fraction of cobalt powder, molybdenum powder, ferroniobium, metallic manganese, and reduced iron powder passing through a 60-mesh sieve is ≥95%.

[0035] In one embodiment of the present invention, the rutile contains TiO2 ≥ 95%, the marble contains CaCO3 ≥ 96%, the fluorite contains CaF2 ≥ 95.0%, SiO2 ≤ 4.5%, the cryolite contains Na3AlF6 ≥ 93%, the potassium titanate contains TiO2 ≥ 65%, K2O + Na2O is 18~22%, Cl ≤ 0.1%, the cobalt powder contains Co ≥ 95%, the molybdenum powder contains Mo ≥ 99.0%, the niobium iron contains Nb ≥ 65%, the metallic manganese contains Mn ≥ 99.8%, the reduced iron powder contains Fe ≥ 98.0%, the sodium alginate contains ash ≤ 30%, K2O is 13.5~18%, the pH value is 6~8, the moisture content is ≤ 15%, the soda ash contains Na2CO3 ≥ 98%, and the CMC contains moisture ≤ 10%.

[0036] The welding electrode of the present invention has the following significant advantages: 1. Excellent weldability: Rutile, cryolite, and marble work synergistically to form short slag, resulting in a soft and stable arc, minimal spatter, smooth weld formation, and very easy slag removal.

[0037] 2. Precise alloy element transition: The cobalt powder, molybdenum powder, niobium iron, and metallic manganese designed in the flux coating are effectively reduced by the slag-forming protection of sodium carbonate (alkali) and cryolite, which achieves precise transition to the deposited metal and ensures the chemical composition and high-temperature performance of the weld.

[0038] 3. Excellent crack resistance: Through the precise proportion of marble, fluorite and other components in the coating, the content of impurities such as S and P in the weld metal is effectively controlled. At the same time, the micro-alloying effect of niobium (Nb) significantly improves the weld's resistance to hot cracking.

[0039] 4. Excellent high-temperature performance: The microstructure of the deposited metal is austenite with a small amount of carbide strengthening phase. The solid solution strengthening effect of cobalt, molybdenum and niobium enables it to maintain high strength and high creep resistance at high temperatures.

[0040] 5. Good workability: The addition of sodium alginate and CMC improves the pressure coating performance, making the coating dense and strong, and less prone to cracking. At the same time, they produce an appropriate viscosity when mixed with water glass, which is beneficial for pressure coating molding.

[0041] Please see Figure 1 The present invention also provides a method for preparing welding electrodes for welding nickel-chromium-cobalt-molybdenum-based high-temperature alloys, comprising the following steps: S1. Weigh each component of the medicinal peel according to the ratio, put them into a mixer and mix evenly to obtain medicinal peel powder; S2. Add binder to the drug coating powder and stir evenly to obtain drug coating coating; S3. Place the coating material in a welding electrode coating machine and press it onto the surface of the welding core to obtain a semi-finished welding electrode. S4. After air-drying the semi-finished welding electrode at room temperature, perform a drying process to obtain a welding electrode for welding nickel-chromium-cobalt-molybdenum high-temperature alloys.

[0042] In step S1, the components of the drug coating are weighed according to the following proportions: rutile 22-30%, marble 29-38%, fluorite 3.5-5.0%, cryolite 18-24%, potassium titanate 3.5-5.0%, cobalt powder 0.8-1.5%, molybdenum powder 0.8-1.5%, ferroniobium 1.5-3.0%, metallic manganese 0.8-1.5%, reduced iron powder 0.8-1.5%, sodium alginate 0.4-1.0%, baking soda 0.8-1.5%, and CMC 0.4-1.0%. For example, to ensure uniform mixing, the mixing time is no less than 60 minutes.

[0043] In step S2, the mass of the binder is 18-20% of the total mass of the drug coating powder. For example, the binder is a water glass binder with a modulus of 1:1.

[0044] In step S3, the pressure applied when the coating material is pressed onto the surface of the core is 8~15MPa, for example, any value of 8~15MPa such as 8MPa, 10MPa, 12MPa or 15MPa.

[0045] In step S4, the drying process includes: first drying at 100~150℃ for 1~2 hours, and then drying at 300~350℃ for 1~1.5 hours.

[0046] The method for preparing welding electrodes for welding nickel-chromium-cobalt-molybdenum high-temperature alloys according to the present invention is simple, easy to control, and suitable for industrial production.

[0047] The technical solution of the present invention will be described in detail below through several specific embodiments. Unless otherwise stated, the raw materials and reagents used in the following embodiments are all commercially available products, or can be prepared by conventional methods in the art, and the instruments used in the embodiments are all commercially available.

[0048] Example 1 The preparation method of the welding electrode used for welding nickel-chromium-cobalt-molybdenum high-temperature alloys in this embodiment is as follows: The components of the flux coating are weighed according to the following proportions: rutile 30%, marble 32%, fluorite 4.1%, cryolite 20%, potassium titanate 4.5%, cobalt powder 1.2%, molybdenum powder 1.2%, ferroniobium 2.5%, metallic manganese 1%, reduced iron powder 1.2%, sodium alginate 0.6%, soda ash 1.1%, and CMC 0.6%. A binder is added to the flux coating powder, and the mixture is stirred evenly to obtain the flux coating. The flux coating is then pressed onto the surface of the welding core under a pressure of 8 MPa to obtain a semi-finished welding electrode. After the semi-finished welding electrode is air-dried at room temperature, it is first dried at 100℃ for 2 hours and then dried at 320℃ for 1.3 hours to obtain a welding electrode for welding nickel-chromium-cobalt-molybdenum high-temperature alloys.

[0049] In this embodiment, the mass of the coating accounts for 45.25% of the total mass of the welding electrode, and the mass of the binder accounts for 18.7% of the total mass of the coating powder.

[0050] Example 2 The preparation method of the welding electrode used for welding nickel-chromium-cobalt-molybdenum high-temperature alloys in this embodiment is as follows: The components of the flux coating are weighed according to the following proportions: rutile 26%, marble 35%, fluorite 4.8%, cryolite 21%, potassium titanate 4%, cobalt powder 1.5%, molybdenum powder 1.5%, ferroniobium 3%, metallic manganese 0.8%, reduced iron powder 0.8%, sodium alginate 0.4%, baking soda 0.8%, and CMC 0.4%. A binder is added to the flux coating powder, and the mixture is stirred evenly to obtain the flux coating. The flux coating is then pressed onto the surface of the welding core under a pressure of 15 MPa to obtain a semi-finished welding electrode. After the semi-finished welding electrode is air-dried at room temperature, it is first dried at 150℃ for 1 hour and then dried at 300℃ for 1.5 hours to obtain a welding electrode for welding nickel-chromium-cobalt-molybdenum high-temperature alloys.

[0051] In this embodiment, the mass of the coating accounts for 44% of the total mass of the welding electrode, and the mass of the binder accounts for 20% of the total mass of the coating powder.

[0052] Example 3 The preparation method of the welding electrode used for welding nickel-chromium-cobalt-molybdenum high-temperature alloys in this embodiment is as follows: The components of the flux coating are weighed according to the following proportions: rutile 30%, marble 29%, fluorite 4.3%, cryolite 22%, potassium titanate 5%, cobalt powder 0.9%, molybdenum powder 0.8%, ferroniobium 2%, metallic manganese 1.5%, reduced iron powder 1.5%, sodium alginate 1%, baking soda 1.3%, and CMC 0.7%. A binder is added to the flux coating powder, and the mixture is stirred evenly to obtain the flux coating. The flux coating is then pressed onto the surface of the welding core under a pressure of 10 MPa to obtain a semi-finished welding electrode. After the semi-finished welding electrode is air-dried at room temperature, it is first dried at 130℃ for 1.5 hours and then dried at 350℃ for 1 hour to obtain a welding electrode for welding nickel-chromium-cobalt-molybdenum high-temperature alloys.

[0053] In this embodiment, the mass of the coating accounts for 46% of the total mass of the welding electrode, and the mass of the binder accounts for 18% of the total mass of the coating powder.

[0054] Example 4 The preparation method of the welding electrode used for welding nickel-chromium-cobalt-molybdenum high-temperature alloys in this embodiment is as follows: The components of the flux coating are weighed according to the following proportions: 28% rutile, 38% marble, 3.5% fluorite, 18% cryolite, 3.5% potassium titanate, 0.8% cobalt powder, 1.1% molybdenum powder, 1.5% ferroniobium, 1.3% metallic manganese, 1% reduced iron powder, 0.8% sodium alginate, 1.5% baking soda, and 1% CMC. A binder is added to the flux coating powder, and the mixture is stirred evenly to obtain the flux coating. The flux coating is then pressed onto the surface of the welding core under a pressure of 12 MPa to obtain a semi-finished welding electrode. After the semi-finished welding electrode is air-dried at room temperature, it is first dried at 140℃ for 1.5 hours and then dried at 350℃ for 1 hour to obtain a welding electrode for welding nickel-chromium-cobalt-molybdenum high-temperature alloys.

[0055] In this embodiment, the mass of the coating accounts for 45% of the total mass of the welding electrode, and the mass of the binder accounts for 19% of the total mass of the coating powder.

[0056] Example 5 The preparation method of the welding electrode used for welding nickel-chromium-cobalt-molybdenum high-temperature alloys in this embodiment is as follows: The components of the flux coating are weighed according to the following proportions: 22% rutile, 33% marble, 5% fluorite, 24% cryolite, 5% potassium titanate, 1.5% cobalt powder, 1.3% molybdenum powder, 2.2% ferroniobium, 1.5% metallic manganese, 1% reduced iron powder, 1% sodium alginate, 1.5% baking soda, and 1% CMC. A binder is added to the flux coating powder, and the mixture is stirred evenly to obtain the flux coating. The flux coating is then pressed onto the surface of the welding core under a pressure of 12 MPa to obtain a semi-finished welding electrode. After the semi-finished welding electrode is air-dried at room temperature, it is first dried at 140℃ for 1.5 hours and then dried at 300℃ for 1.5 hours to obtain a welding electrode for welding nickel-chromium-cobalt-molybdenum high-temperature alloys.

[0057] In this embodiment, the mass of the coating accounts for 44% of the total mass of the welding electrode, and the mass of the binder accounts for 19% of the total mass of the coating powder.

[0058] In this invention, the welding core is a NiCrCoMo-1 alloy, the binder is a water glass binder with a modulus of 1:1, and the diameter of the welding rod is 4.00 mm.

[0059] The composition and content of NiCrCoMo-1 alloy during welding in this invention are shown in Table 1. The content of each component in the coating of the welding electrodes in Examples 1 to 5 is shown in Table 2. Welding of stainless steel 617 nickel-based high-temperature alloy plates was carried out using the welding electrodes prepared in Examples 1 to 5. Butt welding tests were conducted using manual arc welding with a 60° V-groove and 6 layers and 6 passes. The welding parameters are shown in Table 3. Four weld metal test cards were welded in each example to compare the uniformity of the chemical composition of the weld metal. The element content in the weld metal is shown in Table 4. The mechanical properties and welding processability of the weld metal are shown in Table 5.

[0060] Table 1. Composition and content of NiCrCoMo-1 alloy

[0061] Table 2. Content of each component in the electrode coating of Examples 1 to 5

[0062] Table 3 Welding parameters for welding using the electrodes prepared in Examples 1 to 5

[0063] Table 4. Element content of weld metal during welding using electrodes prepared in Examples 1 to 5

[0064] Table 5. Mechanical properties and welding processability of the weld metal deposited using the electrodes prepared in Examples 1 to 5.

[0065] As can be seen from Table 5, the welding electrodes prepared by this invention have good arc stability, good slag removal, beautiful forming, and easy slag removal, with a slag removal rate greater than 95%. The deposited metal has stable composition and excellent mechanical properties, meeting and exceeding the relevant standard requirements of NiCrCoMo-1 welding materials, especially showing excellent performance in high-temperature creep strength tests.

[0066] This invention relates to a welding electrode coating for welding nickel-chromium-cobalt-molybdenum high-temperature alloys. Through the scientific proportions and synergistic effects of its components, the coating achieves significant beneficial effects. Specifically, the formulation, through the synergistic effect of high proportions of rutile, marble, and cryolite, constructs a slag system with suitable high-temperature viscosity and rapid solidification characteristics. The resulting slag provides strong support for the molten pool, perfectly meeting the requirements for molten pool control in all-position welding (especially horizontal and vertical welding). Simultaneously, fluorite and cryolite jointly regulate the slag's fluidity and surface tension, promoting gas escape and impurity flotation during welding, effectively suppressing porosity and inclusions. Furthermore, the combined deoxidation of the coating by metallic manganese and reduced iron powder, along with strict control of harmful impurity content, ensures a smooth transition of alloying elements and a pure and stable weld metal composition, ultimately resulting in a high-quality weld with dense internal structure, smooth and aesthetically pleasing appearance, and an extremely low defect rate.

[0067] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A welding electrode for welding nickel-chromium-cobalt-molybdenum based high-temperature alloys, characterized in that, The coating includes a core and a flux coating. The flux coating, by its total mass, comprises the following components in the following mass percentages: rutile 22-30%, marble 29-38%, fluorite 3.5-5.0%, cryolite 18-24%, potassium titanate 3.5-5.0%, cobalt powder 0.8-1.5%, molybdenum powder 0.8-1.5%, ferroniobium 1.5-3.0%, metallic manganese 0.8-1.5%, reduced iron powder 0.8-1.5%, sodium alginate 0.4-1.0%, baking soda 0.8-1.5%, and CMC 0.4-1.0%.

2. The welding electrode according to claim 1, characterized in that, The coating material accounts for 44-46% of the total mass of the welding electrode.

3. The welding electrode according to claim 1, characterized in that, The welding core is a NiCrCoMo-1 alloy.

4. The welding electrode according to claim 1, characterized in that, The rutile contains 100% sieve-passing 60-mesh sieve and ≤20% sieve-passing 200-mesh sieve; the marble contains ≥95% sieve-passing 60-mesh sieve and ≤50% sieve-passing 200-mesh sieve; the fluorite contains ≥95% sieve-passing 80-mesh sieve; the cryolite contains ≥95% sieve-passing 60-mesh sieve; the potassium titanate contains ≥95% sieve-passing 80-mesh sieve and ≤40% sieve-passing 200-mesh sieve; and the cobalt powder, molybdenum powder, ferroniobium, metallic manganese, and reduced iron powder contain ≥95% sieve-passing 60-mesh sieve.

5. The welding electrode according to claim 1, characterized in that, The rutile contains TiO2 ≥ 95%, the marble contains CaCO3 ≥ 96%, the fluorite contains CaF2 ≥ 95.0%, SiO2 ≤ 4.5%, the cryolite contains Na3AlF6 ≥ 93%, the potassium titanate contains TiO2 ≥ 65%, K2O + Na2O is 18~22%, Cl ≤ 0.1%, the cobalt powder contains Co ≥ 95%, the molybdenum powder contains Mo ≥ 99.0%, the niobium iron contains Nb ≥ 65%, the metallic manganese contains Mn ≥ 99.8%, the reduced iron powder contains Fe ≥ 98.0%, the sodium alginate contains ash ≤ 30%, K2O is 13.5~18%, pH is 6~8, moisture is ≤ 15%, and the alkali powder contains Na2CO3 ≥ 98%.

6. A method for preparing a welding electrode for welding nickel-chromium-cobalt-molybdenum based high-temperature alloys according to any one of claims 1 to 5, characterized in that, Includes the following steps: Weigh each component of the medicinal peel according to the formula, put them into a mixer and mix them evenly to obtain the medicinal peel powder; A binder is added to the powdered drug coating and stirred until homogeneous to obtain a drug coating material; The coating is pressed onto the surface of the welding core to obtain a semi-finished welding electrode. The semi-finished welding electrode is air-dried at room temperature and then dried to obtain the welding electrode used for welding nickel-chromium-cobalt-molybdenum high-temperature alloys.

7. The preparation method according to claim 6, characterized in that, The mass of the binder is 18-20% of the total mass of the drug coating powder.

8. The preparation method according to claim 6, characterized in that, The adhesive is a water glass adhesive with a modulus of 1:

1.

9. The preparation method according to claim 6, characterized in that, The pressure applied when the coating is pressed onto the surface of the core is 8-15 MPa.

10. The preparation method according to claim 6, characterized in that, The drying process includes: first drying at 100~150℃ for 1~2 hours, and then drying at 300~350℃ for 1~1.5 hours.

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