Multi-element nickel alloy composite welding wire with low thermal crack sensitivity and preparation method of multi-element nickel alloy composite welding wire

Abstract

The invention belongs to the field of metal material processing, and particularly relates to a multi-element nickel alloy composite welding wire with low thermal crack sensitivity and a preparation method of the multi-element nickel alloy composite welding wire with the low thermal crack sensitivity. The welding wire comprises the following powder raw materials in parts by weight: 0.01 to 0.05 percent of C, 0.10 to 0.20 percent of Si, 28.5 to 30.5 percent of Cr, 7.0 to 11.0 percent of Fe, less than or equal to 1.0 percent of Mn, 1.0 to 2.0 percent of Co, 4.0 to 5.0 percent of Mo, 0.001 to 0.005 percent of B, 0.1 to 0.2 percent of Al + Ti, 0.005 to 0.020 percent of Zr, 1.0 to 2.0 percent of Nb, 0.1 to 0.4 percent of Ta, 0.5 to 1.0 percent of Sn, 0.20 to 0.30 percent of RE, less than 0.005 percent of S, less than 0.005 percent of P and the balance of Ni. And the plating layer comprises a titanium carbide layer and a nickel layer from inside to outside. A welding wire raw material is subjected to smelting, high and low temperature refining, annealing, forging and rolling, multi-pass drawing-annealing, solid solution-aging treatment and acid pickling, coating and plating to obtain the nickel-based alloy welding wire, and the problems that in the prior art, when a nickel-based alloy welding material is used for welding, cracks are prone to being generated, and the strength is low due to hot corrosion can be effectively solved.

Description

Technical Field

[0001] The present invention belongs to the field of metal materials, and in particular relates to a low thermal crack sensitivity multi-element nickel alloy composite welding wire and a preparation method thereof. Background Art

[0002] Nickel, a primary element in current high-temperature alloys, is one of the few alloying elements that enhances alloy strength without significantly diminishing its plasticity. It exhibits excellent resistance to high temperatures, oxidation, and corrosion. However, due to their high viscosity, poor fluidity, and weldability, nickel-based alloys are highly susceptible to hot cracking during welding. Hot cracking occurs at high temperatures and does not extend at room temperature. This is primarily due to the incorporation of sulfur, lead, phosphorus, or other low-melting-point metals, which form intergranular films that cause severe embrittlement at high temperatures. In particular, sulfur and phosphorus eutectics have melting points significantly lower than nickel-iron, and liquid films of these low-melting-point eutectics remain at grain boundaries during weld crystallization. Furthermore, the high heat input from welding causes overheating of the weld joint, resulting in coarse grains. These low-melting-point eutectics are concentrated at the coarse columnar grain boundaries. These eutectics, located at grain boundaries, have low strength and are highly brittle, making them susceptible to hot cracking under the high residual stresses of welding. Another defect that must be avoided during welding is porosity. Nickel alloy molten pools are thick and have poor fluidity, making them prone to porosity during rapid cooling. Oxygen, hydrogen, nitrogen, carbon dioxide, and carbon monoxide are extremely soluble in molten nickel-based alloys, but their solubility is greatly reduced in the solid state. As nickel-based alloy welding cools from high temperature, the solubility of these gases in the deposited metal also decreases. The released gases cannot completely escape from the poorly fluid liquid nickel before the weld solidifies, forming pores, often near the fusion line. Current nickel-based alloys have poor weldability and are unable to effectively address the aforementioned hot cracking issue. Consequently, the requirements for welding materials are extremely high, manufacturing is extremely difficult, and the industry has long been monopolized by European and American countries, making the solution to the hot cracking issue urgent. Summary of the Invention

[0003] The present invention aims to address the problem of cracks easily forming during welding of nickel alloy wires in the prior art by providing a novel multicomponent nickel alloy composite welding wire with low thermal crack sensitivity and a method for preparing the same. This novel material utilizes a composite component structure to effectively address this problem. To achieve this objective, the present invention employs the following technical solutions to solve the technical problem: The present invention provides a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, comprising a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.01-0.05%, Si: 0.10-0.20%, Cr: 28.5-30.5%, Fe: 7.0-11.0%, Mn: ≤1.0%, Co: 1.0-2.0%, Mo: 4.0-5.0%, B: 0.001-0.005%, Al+Ti: 0.1-0.2%, Zr: 0.005-0.020%, Nb: 1.0-2.0%, Ta: 0.1-0.4%, Sn: 0.5-1.0%, RE: 0.20-0.30%, S: <0.005%, P: <0.005%, and Ni as the remainder; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0004] Furthermore, the total amount of the above Cr and Mo is not less than 33.5%.

[0005] Furthermore, the weight ratio of the above-mentioned Al to Ti is (2.0-4.0):1.

[0006] Furthermore, the weight ratio of Mn to Si is (5.0-7.0):1.

[0007] Furthermore, the above RE is one or more of Y, Ce, Sm, Gd, and Nd.

[0008] Furthermore, the weight percentage of titanium carbide in the composite welding wire is 0.1-1.0%.

[0009] The present invention also provides a method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, comprising the following steps: S11: Raw materials are weighed according to the mass percentage of the formula and processed to obtain a uniform and refined mixed powder; S12: placing the mixed powder into a smelting furnace for smelting, performing high-temperature refining, low-temperature refining, and then remelting and refining, and casting into an alloy ingot; S13: After annealing the alloy ingot, forging and rolling are performed to prepare alloy wire rods; S14: performing multiple drawing-annealing steps on the alloy wire rod after pretreatment; S15: Processing the alloy wire into the required size and performing solution-aging treatment; S16: pickling the alloy wire; coating; S17: After pre-treating the surface, a titanium carbide layer is plated to obtain a welding wire; and S18: Plating a nickel layer on the surface of the welding wire to obtain a target product, i.e., a multi-element nickel alloy composite welding wire with low thermal crack sensitivity.

[0010] Furthermore, the preparation method of the electroplating solution of the titanium carbide layer is: Graphene oxide, nickel salt, and surfactant were added to deionized water, ultrasonically dispersed for 1 hour, and then titanium carbide and boric acid were added, and ultrasonic dispersion was continued for another hour to obtain an electroplating solution; The usage ratio of the graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 1-5g:200g:1L:60-100g:30g; The amount of the above surfactant is 5% of the mass of graphene oxide; The nickel salt is nickel sulfate and / or nickel chloride; and The particle size of the titanium carbide is 5-10 μm.

[0011] Furthermore, the above-mentioned surfactant is a non-ionic surfactant.

[0012] Furthermore, the graphene oxide is prepared by Hummers oxidation method.

[0013] The present invention has the following beneficial effects: (1) The present invention provides a multi-element nickel alloy composite welding wire with low thermal crack sensitivity. The welding wire structure uses Ni as the matrix. Cr can improve the alloy's high-temperature oxidation resistance and corrosion resistance; Mo can refine the grains and improve the alloy's thermal stability; and Co can improve thermal stability and creep resistance. At the same time, Cr, Mo, and Co can react with C to form carbides. Hard phases such as chromium carbide are dispersed in the solid solution-strengthened matrix, improving high-temperature strength and plasticity. Furthermore, the improvement in high-temperature oxidation resistance and high-temperature strength can effectively suppress weld porosity caused by oxidation, effectively improving weld strength, and thus reducing thermal crack sensitivity.

[0014] (2) The present invention provides a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, wherein a certain amount of Al and Ti elements are added to the welding wire alloy. On the one hand, Al and Ti can improve the weldability of the alloy. They have a strong affinity with oxygen and can act as deoxidizing elements to protect the weld from oxidation, thereby effectively inhibiting the formation of CO and N2 pores and facilitating the formation of the weld. On the other hand, Al will generate Al2O3 during the high-temperature oxidation process of the alloy. This oxide structure is beneficial to improving the high-temperature oxidation resistance of the alloy, increasing the thermal strength, and reducing the thermal cracking sensitivity.

[0015] (3) The present invention provides a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, the coating of which is a titanium carbide layer and a nickel layer. First, titanium carbide particles are directly and evenly introduced into the weld during welding, which can not only play the role of refining grains and pinning grain boundaries, but also significantly reduce thermal crack sensitivity; it also improves hardness and wear resistance; second, the graphene oxide structure in the titanium carbide layer can, on the one hand, react with the metal to effectively enhance the interlayer bonding strength with the welding wire and the nickel coating; on the other hand, it can improve mechanical properties through grain refinement, pinning grain boundaries, and stress transfer mechanisms, further reducing thermal crack sensitivity; third, the titanium carbide particles, graphene and other structures in the titanium carbide layer work synergistically, have excellent electrical conductivity, can reduce welding defects, and improve welding efficiency. DETAILED DESCRIPTION

[0016] The present invention will be described in detail below with reference to the following examples. However, it should be understood that the following examples are merely illustrative of the embodiments of the present invention and are not intended to limit the scope of the present invention.

[0017] The purpose of the present invention is to develop a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, so as to solve the problem that cracks are easily generated during the welding process of existing nickel alloy welding wires. The idea of ​​implementation is: with Ni as the main component, the addition of high-temperature resistant elements such as Cr, Mo, and Co is added through formula design to achieve solid solution strengthening, improve oxidation resistance and thermal corrosion resistance; add appropriate amounts of Mn, Si and other elements to improve grain boundary purity and reduce thermal brittleness; at the same time, add precipitation strengthening elements Al, Ti, Ta, RE and the like to improve high-temperature strength and purify grain boundaries; finally, carry out titanium carbide coating process in the alloy wire, comprehensively improve mechanical properties and reduce thermal crack defects. In addition, due to the problem of bonding strength between titanium carbide coating and alloy wire electroplating, graphene oxide is introduced into the titanium carbide coating to carry out coordination reaction between graphene and metal, improve interlayer bonding strength, and at the same time further improve weld mechanical properties and reduce thermal crack sensitivity. The embodiments of the present invention are as follows: An embodiment of the present invention provides a low hot crack sensitivity multi-element nickel alloy composite welding wire, comprising a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.01-0.05%, Si: 0.10-0.20%, Cr: 28.5-30.5%, Fe: 7.0-11.0%, Mn: ≤1.0%, Co: 1.0-2.0%, Mo: 4.0-5.0%, B: 0.001-0.005%, Al + Ti: 0.1-0.2%, Zr: 0.005-0.020%, Nb: 1.0-2.0%, Ta: 0.1-0.4%, Sn: 0.5-1.0%, RE: 0.20-0.30%, S: <0.005%, P: <0.005%, Ni balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0018] The total amount of the above Cr and Mo is not less than 33.5%.

[0019] Cr is the primary element that ensures the high-temperature oxidation resistance of the alloy of the present invention and is the most important element for stabilizing the alloy surface. It forms a dense, oxidation- and corrosion-resistant Cr2O3 protective layer on the surface of the base material. Generally, a Cr content exceeding 12% provides excellent high-temperature oxidation resistance. Above 33%, the increased Cr content has little effect on improving high-temperature oxidation resistance and can lead to the precipitation of an α-Cr phase, which is detrimental to mechanical properties. Therefore, the present invention controls the Cr content to between 28.5% and 30.5%.

[0020] Mo increases high-temperature strength and improves the alloy's corrosion resistance, particularly when combined with chromium, resulting in superior pitting corrosion resistance. Mo also enhances the alloy's creep resistance through solid solution strengthening. The addition of Mo significantly improves the welding wire's corrosion resistance and high-temperature strength. Therefore, the present invention limits the Mo content to 4.0-5.0%.

[0021] At the same time, considering the compounding effect of Cr and Mo, the total amount shall not be less than 33.5%.

[0022] The weight ratio of Al to Ti is (2.0-4.0):1.

[0023] Al and Ti can improve the alloy's weldability, acting as deoxidizing elements, facilitating weld formation and strengthening the alloy to a certain extent. Furthermore, Al generates Al2O3 during the alloy's high-temperature oxidation process, an oxide structure that improves the alloy's high-temperature oxidation resistance. However, excessive Al and Ti contents can affect hot workability and weldability, and the resulting oxides can easily cause weld slag inclusions, reducing resistance to hot cracking. Excessive Al+Ti content can lead to the precipitation of secondary phases such as γ and γ', reducing the enhanced high-temperature durability and inducing the precipitation of the harmful σ phase. Furthermore, considering the presence of titanium carbide coating in the coating, the Al+Ti content is controlled within a range of 0.1-0.2% Al+Ti, with a weight ratio of Al to Ti of (2.0-4.0):1.

[0024] The weight ratio of Mn to Si is (5.0-7.0):1.

[0025] The Mn content significantly affects the low-temperature impact toughness of the deposited metal. It also fixes sulfur to form MnS, reducing grain boundary embrittlement. However, excessive Mn content can lead to weak crystallization cracks and high-temperature decompression cracking. Therefore, the present invention limits the Mn content to ≤1.0%.

[0026] As a deoxidizer, Si can improve weld purity, reduce defects, increase weld strength, and reduce the tendency of solidification cracking. However, excessive Si content can cause weld metal to become brittle, reducing plasticity and toughness. Therefore, the present invention controls the Si content to 0.1-0.2%.

[0027] At the same time, considering that Mn and Si have a certain synergistic effect, the weight ratio of Mn to Si is (5.0-7.0):1 for compound use.

[0028] The above RE is one or more of Y, Ce, Sm, Gd, and Nd.

[0029] Rare earth elements (RE) are key functional elements that improve high-temperature oxidation resistance. Adding Cr to nickel alloys improves heat and corrosion resistance. However, at high temperatures, the Cr2O3 formed on the surface easily volatilizes, resulting in reduced oxidation resistance. Adding RE elements forms a new phase, which is beneficial to the formation of the alloy's selective oxidation film, Cr2O3, improving the adhesion between the oxide film and the substrate, inhibiting the volatilization of Cr2O3, reducing the oxidation rate, and improving the alloy's high-temperature oxidation resistance. At the same time, rare earth elements (RE) are strong deoxidizers in the secondary metallurgical process of welding, which can improve crack resistance and improve the welding processability of the wire. Therefore, the RE content is controlled at 0.20-0.30%.

[0030] The weight percentage of titanium carbide in the composite welding wire is 0.1-1.0%.

[0031] First, titanium carbide particles refine the grains and inhibit the generation of solidification cracks; second, the coating surface is highly uniform, reducing oxide inclusions during welding, and in combination with shielding gas, significantly reducing porosity and defects; third, the deposited metal forms a "soft matrix + hard particles" composite structure, which improves the impact resistance of the weld; fourth, the titanium carbide structure can disperse welding residual stress, reduce fatigue crack initiation, and reduce thermal cracking sensitivity. Fifth, the titanium carbide in the coating can play its role in refining grains and pinning grain boundaries by directly and evenly introducing titanium carbide particles into the weld, without increasing the element content of C and Ti, and can also significantly reduce DDC crack sensitivity, and at a lower cost.

[0032] On the other hand, the titanium carbide coating in the present invention contains a graphene oxide structure, which can act as an interlayer binder during the electroplating process to improve the bonding strength between the coatings; during the welding process, it also has the function of improving mechanical properties through grain refinement, pinning grain boundaries, and stress transfer mechanisms, further reducing thermal crack sensitivity. Therefore, the present invention considers that the overall amount of titanium carbide in the composite welding wire is controlled to 0.1-1.0wt%.

[0033] In addition, other important components and functions in the embodiments of the present invention are as follows: The addition of Co achieves solid solution strengthening, improves thermal stability, reduces crack sensitivity, and can inhibit grain boundary sliding, especially in high temperature environments. Therefore, the present invention controls the Co content to 1.0-2.0%.

[0034] Fe is a matrix element of NiCrFe alloy and can improve weld strength through solid solution strengthening. Therefore, the Fe content is controlled within a range of 7.0-11.0% in the present invention.

[0035] Nb is a strengthening element in high-temperature environments. It increases solid solution lattice distortion and lattice atomic bond attraction, strengthening the matrix and achieving significant solid solution strengthening effects. It is also a strong carbide former, forming MC, M6C, or M2C carbides, significantly strengthening the weld metal as a second phase. Furthermore, it can reduce alloying element segregation and improve weld metal plasticity. However, the Nb content must be controlled to prevent Laves phase precipitation. Therefore, the present invention limits the Nb content to 1.0-2.0%.

[0036] Adding trace amounts of Zr and B elements strengthens the grain boundaries and improves the long-term strength of the weld deposited metal, and trace additions will not increase the sensitivity of welding hot cracks.

[0037] Low-melting-point Sn can fill grain boundary microcracks and improve healing ability, but excessive Sn should be avoided to prevent brittleness. Therefore, the present invention controls the Sn content to 0.5-1.0%.

[0038] The present invention also provides a method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, comprising the following steps: S11: Raw materials are weighed according to the mass percentage of the formula and processed to obtain a uniform and refined mixed powder; The above-mentioned treatment process and the above-mentioned treatment process in the following embodiments of the present invention are as follows: the raw material powder is added to ethanol, magnetically stirred at 1000r / min for 3h, and then subjected to 50KHz ultrasonic treatment for 2h to obtain an ethanol suspension; filtration is performed to obtain insoluble matter, which is placed in an 80°C drying oven for drying for 2h, and the insoluble matter is placed in a ball mill, and myristic acid is added, and the ball mill is placed on a high-energy ball mill for ball milling to obtain a uniformly refined mixed powder; wherein the grinding ball material is corundum ball, the ball-to-material mass ratio is 6:1, the ball milling process is 7h, and the ball mill speed is 150-200r / min; The usage ratio of the above-mentioned myristic acid to the total mass of the raw material powder is 2g:100g.

[0039] S12: placing the mixed powder into a smelting furnace for smelting, performing high-temperature refining, low-temperature refining, and then remelting and refining, and casting into an alloy ingot; The above-mentioned high temperature refining is smelting at 1750-1850℃ for 30-45min; The above-mentioned low-temperature refining is smelting at 1650-1700°C for 15-25 minutes; The above remelting is electroslag remelting, and the furnace temperature is 1750-1850℃.

[0040] S13: After annealing the alloy ingot, forging and rolling are performed to prepare alloy wire rods; The above annealing process is heating to 1000-1050℃ and keeping it for 20-35h; The forging process is as follows: at 950°C, the billet is forged into alloy billet I with a forging ratio of 3-4; after tempering at 950-1000°C for 1-2 hours, the billet is forged into alloy billet II at 1050°C with a forging ratio of 5-6; and then the billet is forged into alloy billet III at the same temperature with a forging ratio of 3-4. The above rolling process is to keep the temperature at 1000-1050°C for 0.5-1.5h and hot-roll the steel into Φ4.05.0mm alloy wire rod at 950-1100°C.

[0041] S14: performing multiple drawing-annealing steps on the alloy wire rod after pretreatment; The pretreatment is to heat the alloy wire rod to 950°C for 1.5 hours, oil cool it for softening, boil it in alkali, then wash it with high pressure water, then pickle it with water, and then ultrasonically clean it. The above-mentioned drawing process includes adding a lubricant before drawing and performing multiple drawing processes to obtain the alloy wire; The above annealing is vacuum annealing after 5-8 drawing passes, and the annealing temperature is 640-800°C.

[0042] S15: Processing the alloy wire into the required size and performing solution-aging treatment; The above-mentioned solution-aging treatment is a multi-step graded treatment; specifically, in a nitrogen environment, heating to 950-1100°C, holding for 2-3 hours, further heating to 1100-1170°C, holding for 1-2 hours, and rapid water quenching to obtain a solid solution alloy; the above-mentioned aging is heating to 750-770°C, holding for 10-15 hours, and air cooling.

[0043] S16: pickling the alloy wire; coating; The above pickling and the pickling in the following embodiments of the present invention are all carried out by pickling the alloy wire after the solid solution heat treatment, first pickling it with a mixed pickling solution containing 100g / L nitric acid and 20g / L hydrofluoric acid, controlling the temperature to be ≤50°C and the pickling time to be 10min; finally, cleaning the residual acid on the surface; The above coating and the coating in the following embodiments of the present invention are all obtained by coating a layer of water-soluble coating agent on the surface of the pickled alloy wire, and the coated alloy wire is naturally air-dried.

[0044] S17: After pre-treating the surface, a titanium carbide layer is plated to obtain a welding wire; and Pretreatment: The surface of the high-temperature nickel-based alloy welding wire was cleaned, sanded, and then polished. It was then rinsed in a 50°C mixed solution of sodium hydroxide (20 g / L), trisodium phosphate (30 g / L), and sodium silicate (30 g / L) for 10 minutes. Finally, it was electropolished in a mixture of 80% acetic acid and 20% perchloric acid at a voltage of 27 V for 7 seconds to produce the pretreated welding wire. Titanium carbide plating: Prepare titanium carbide electroplating solution, the preparation method is as follows: Graphene oxide, nickel salt, and surfactant were added to deionized water, ultrasonically dispersed for 1 hour, and then titanium carbide and boric acid were added, and ultrasonic dispersion was continued for another hour to obtain an electroplating solution; The usage ratio of the graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 1-5g:200g:1L:60-100g:30g; The amount of the above surfactant is 5% of the mass of graphene oxide; The surfactant is a nonionic surfactant, which may be polyvinyl pyrrolidone or Tween 80, etc.; Tween 80 is preferred.

[0045] The graphene oxide is prepared by Hummers oxidation method, and the hydroxyl content is 8 mmol / g.

[0046] The nickel salt is nickel sulfate and / or nickel chloride; and The particle size of the titanium carbide is 5-10 μm.

[0047] The electroplating process parameters of the titanium carbide layer are as follows: current density 3A / dm 2 , electroplating time 0.5h, electroplating temperature 45℃, stirring speed 300r / min.

[0048] S18: Plating a nickel layer on the surface of the welding wire to obtain a target product, i.e., a multi-element nickel alloy composite welding wire with low thermal crack sensitivity.

[0049] The nickel plating layer and the nickel plating process in the following embodiments of the present invention are as follows: nickel plating: preparing a Watt-type electrolyte, the electroplating solution includes 400g / L nickel sulfate, 45g / L nickel chloride, 50g / L boric acid, and the balance is water, and then electroplating a nickel layer on the titanium carbide coating of welding wire III to obtain a nuclear power high-temperature nickel-based alloy composite welding wire. The electroplating process parameters are a current density of 3A / dm 2 , electroplating time 10min, electroplating temperature 45℃, stirring speed 300r / min.

[0050] In order to further understand the present invention, the low thermal crack sensitivity multi-element nickel alloy composite welding wire provided by the present invention is described in detail below in conjunction with specific embodiments. The protection scope of the present invention is not limited by the following embodiments.

[0051] Example 1 This embodiment provides a low hot crack sensitivity multi-element nickel alloy composite welding wire, comprising a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.03%, Si: 0.15%, Cr: 29.5%, Fe: 9.0%, Mn: 0.9%, Co: 1.4%, Mo: 4.6%, B: 0.003%, Al + Ti: 0.17%, Zr: 0.010%, Nb: 1.6%, Ta: 0.3%, Sn: 0.8%, RE: 0.25%, S: 0.002%, P: 0.002%, and Ni as the balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0052] The weight ratio of Al to Ti is 3.0:1.

[0053] The above RE is a mixture of Y and Ce in a mass ratio of 2:1.

[0054] The weight percentage of titanium carbide in the composite welding wire is 0.5%.

[0055] This embodiment also provides a method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, comprising the following steps: S11: Raw materials are weighed according to the mass percentage of the formula and processed to obtain a uniform and refined mixed powder; S12: placing the mixed powder into a smelting furnace for smelting, performing high-temperature refining, low-temperature refining, and then remelting and refining, and casting into an alloy ingot; The above high temperature refining is smelting at 1800°C for 35 minutes; The above-mentioned low-temperature refining is smelting at 1680°C for 20 minutes; The above remelting is electroslag remelting, and the furnace temperature is 1800°C.

[0056] S13: After annealing the alloy ingot, forging and rolling are performed to prepare alloy wire rods; The above annealing process is heating to 1030°C and keeping it at this temperature for 27h; The forging process is as follows: at 950°C, the billet is forged into alloy billet I with a forging ratio of 3.5; after tempering at 980°C for 1.5 hours, the billet is forged into alloy billet II at 1050°C with a forging ratio of 5.5; and then forged into alloy billet III at the same temperature with a forging ratio of 3.5. The above rolling process is to keep the temperature at 1020°C for 1 hour and hot-roll the alloy wire rod at 1040°C into Φ4.5mm.

[0057] S14: performing multiple drawing-annealing steps on the alloy wire rod after pretreatment; The pretreatment is to heat the alloy wire rod to 950°C for 1.5 hours, oil cool it for softening, boil it in alkali, then wash it with high pressure water, then pickle it with water, and then ultrasonically clean it. The above-mentioned drawing process includes adding a lubricant before drawing and performing multiple drawing processes to obtain the alloy wire; The above annealing is vacuum annealing after 7 drawing passes, and the annealing temperature is 730°C.

[0058] S15: Processing the alloy wire into the required size and performing solution-aging treatment; The above-mentioned solution-aging treatment is a multi-step graded treatment; specifically, in a nitrogen environment, heating to 1000°C, holding for 2.5 hours, continuing to heat to 1150°C, holding for 1.5 hours, and rapid water quenching to obtain a solid solution alloy; the above-mentioned aging is heating to 760°C, holding for 12 hours, and air cooling.

[0059] S16: pickling the alloy wire; coating; S17: After pre-treating the surface, a titanium carbide layer is plated to obtain a welding wire; and Pretreatment: The surface of the high-temperature nickel-based alloy welding wire was cleaned, sanded, and then polished. It was then rinsed in a 50°C mixed solution of sodium hydroxide (20 g / L), trisodium phosphate (30 g / L), and sodium silicate (30 g / L) for 10 minutes. Finally, it was electropolished in a mixture of 80% acetic acid and 20% perchloric acid at a voltage of 27 V for 7 seconds to produce the pretreated welding wire. Titanium carbide plating: Prepare titanium carbide electroplating solution, the preparation method is as follows: Graphene oxide, nickel salt, and Tween 80 were added to deionized water, ultrasonically dispersed for 1 hour, and then titanium carbide and boric acid were added, and ultrasonic dispersion was continued for another hour to obtain an electroplating solution; The usage ratio of the graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 3g:200g:1L:80g:30g; The amount of Tween 80 used is 5% of the mass of graphene oxide.

[0060] The graphene oxide is prepared by Hummers oxidation method.

[0061] The nickel salt is nickel sulfate and nickel chloride in a mass ratio of 8:1.

[0062] The electroplating process parameters of the titanium carbide layer are as follows: current density 3A / dm 2 , electroplating time 0.5h, electroplating temperature 45℃, stirring speed 300r / min.

[0063] S18: Plating a nickel layer on the surface of the welding wire to obtain a target product, i.e., a multi-element nickel alloy composite welding wire with low thermal crack sensitivity.

[0064] Example 2 This embodiment provides a low hot crack sensitivity multi-element nickel alloy composite welding wire, comprising a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.01%, Si: 0.20%, Cr: 30.5%, Fe: 11.0%, Mn: 1.0%, Co: 1.0%, Mo: 4.0%, B: 0.005%, Al + Ti: 0.20%, Zr: 0.005%, Nb: 2.0%, Ta: 0.4%, Sn: 1.0%, RE: 0.20%, S: 0.002%, P: 0.002%, and Ni as the balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0065] The weight ratio of Al to Ti is 3.0:1.

[0066] The above RE is a mixture of Y and Ce in a mass ratio of 2:1.

[0067] The weight percentage of titanium carbide in the composite welding wire is 0.5%.

[0068] This embodiment also provides a method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, comprising the following steps: S11: Raw materials are weighed according to the mass percentage of the formula and processed to obtain a uniform and refined mixed powder; S12: placing the mixed powder into a smelting furnace for smelting, performing high-temperature refining, low-temperature refining, and then remelting and refining, and casting into an alloy ingot; The above high temperature refining is smelting at 1850°C for 30 minutes; The above low temperature refining is smelting at 1700°C for 15 minutes; The above remelting is electroslag remelting, and the furnace temperature is 1850°C.

[0069] S13: After annealing the alloy ingot, forging and rolling are performed to prepare alloy wire rods; The above annealing process is heating to 1050°C and keeping it warm for 20 hours; The forging process is as follows: at 950°C, the billet is forged into alloy billet I with a forging ratio of 4; after tempering at 950°C for 2 hours, the billet is forged into alloy billet II at 1050°C with a forging ratio of 5; and then forged into alloy billet III at the same temperature with a forging ratio of 4. The above rolling process is to keep the temperature at 1050°C for 0.5h and hot-roll the alloy wire rod at 1100°C into Φ5.0mm.

[0070] S14: performing multiple drawing-annealing steps on the alloy wire rod after pretreatment; The pretreatment is to heat the alloy wire rod to 950°C for 1.5 hours, oil cool it for softening, boil it in alkali, then wash it with high pressure water, then pickle it with water, and then ultrasonically clean it. The above-mentioned drawing process includes adding a lubricant before drawing and performing multiple drawing processes to obtain the alloy wire; The above annealing is vacuum annealing after 5 drawing passes, and the annealing temperature is 800°C.

[0071] S15: Processing the alloy wire into the required size and performing solution-aging treatment; The above-mentioned solution-aging treatment is a multi-step graded treatment; specifically, in a nitrogen environment, heating to 1100°C, holding for 2 hours, continuing to heat to 1170°C, holding for 1 hour, and rapid water quenching to obtain a solid solution alloy; the above-mentioned aging is heating to 770°C, holding for 10 hours, and air cooling.

[0072] S16: pickling the alloy wire; coating; S17: After pre-treating the surface, a titanium carbide layer is plated to obtain a welding wire; and Pretreatment: The surface of the high-temperature nickel-based alloy welding wire was cleaned, sanded, and then polished. It was then rinsed in a 50°C mixed solution of sodium hydroxide (20 g / L), trisodium phosphate (30 g / L), and sodium silicate (30 g / L) for 10 minutes. Finally, it was electropolished in a mixture of 80% acetic acid and 20% perchloric acid at a voltage of 27 V for 7 seconds to produce the pretreated welding wire. Titanium carbide plating: Prepare titanium carbide electroplating solution, the preparation method is as follows: Graphene oxide, nickel salt, and Tween 80 were added to deionized water, ultrasonically dispersed for 1 hour, and then titanium carbide and boric acid were added, and ultrasonic dispersion was continued for another hour to obtain an electroplating solution; The usage ratio of the graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 3g:200g:1L:80g:30g; The amount of Tween 80 used is 5% of the mass of graphene oxide.

[0073] The graphene oxide is prepared by Hummers oxidation method.

[0074] The above nickel salt is nickel sulfate.

[0075] The electroplating process parameters of the titanium carbide layer are as follows: current density 3A / dm 2 , electroplating time 0.5h, electroplating temperature 45℃, stirring speed 300r / min.

[0076] S18: Plating a nickel layer on the surface of the welding wire to obtain a target product, i.e., a multi-element nickel alloy composite welding wire with low thermal crack sensitivity.

[0077] Example 3 This embodiment provides a low hot crack sensitivity multi-element nickel alloy composite welding wire, comprising a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.05%, Si: 0.10%, Cr: 28.5%, Fe: 7.0%, Mn: 0.7%, Co: 2.0%, Mo: 5.0%, B: 0.001%, Al + Ti: 0.10%, Zr: 0.020%, Nb: 1.0%, Ta: 0.1%, Sn: 0.5%, RE: 0.30%, S: 0.002%, P: 0.002%, and Ni as the balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0078] The weight ratio of Al to Ti is 3.0:1.

[0079] The above RE is a mixture of Y and Ce in a mass ratio of 2:1.

[0080] The weight percentage of titanium carbide in the composite welding wire is 0.5%.

[0081] This embodiment also provides a method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, comprising the following steps: S11: Raw materials are weighed according to the mass percentage of the formula and processed to obtain a uniform and refined mixed powder; S12: placing the mixed powder into a smelting furnace for smelting, performing high-temperature refining, low-temperature refining, and then remelting and refining, and casting into an alloy ingot; The above high temperature refining is smelting at 1750℃ for 45min; The above-mentioned low-temperature refining is smelting at 1650°C for 25 minutes; The above remelting is electroslag remelting, and the furnace temperature is 1750°C.

[0082] S13: After annealing the alloy ingot, forging and rolling are performed to prepare alloy wire rods; The above annealing process is heating to 1000°C and keeping it at this temperature for 35h; The forging process is as follows: at 950°C, the billet is forged into alloy billet I with a forging ratio of 3; after tempering at 1000°C for 1 hour, the billet is forged into alloy billet II at 1050°C with a forging ratio of 6; and then forged into alloy billet III at the same temperature with a forging ratio of 3; The above rolling process is to keep the temperature at 1000°C for 1.5 hours and then hot-roll the alloy wire rod at 950°C into Φ4.0mm.

[0083] S14: performing multiple drawing-annealing steps on the alloy wire rod after pretreatment; The pretreatment is to heat the alloy wire rod to 950°C for 1.5 hours, oil cool it for softening, boil it in alkali, then wash it with high pressure water, then pickle it with water, and then ultrasonically clean it. The above-mentioned drawing process includes adding a lubricant before drawing and performing multiple drawing processes to obtain the alloy wire; The above annealing is vacuum annealing after 8 drawing passes, and the annealing temperature is 640°C.

[0084] S15: Processing the alloy wire into the required size and performing solution-aging treatment; The above-mentioned solution-aging treatment is a multi-step graded treatment; specifically, in a nitrogen environment, heating to 950°C, holding for 3 hours, continuing to heat to 1100°C, holding for 2 hours, and rapid water quenching to obtain a solid solution alloy; the above-mentioned aging is heating to 750°C, holding for 15 hours, and air cooling.

[0085] S16: pickling the alloy wire; coating; S17: After pre-treating the surface, a titanium carbide layer is plated to obtain a welding wire; and Pretreatment: The surface of the high-temperature nickel-based alloy welding wire was cleaned, sanded, and then polished. It was then rinsed in a 50°C mixed solution of sodium hydroxide (20 g / L), trisodium phosphate (30 g / L), and sodium silicate (30 g / L) for 10 minutes. Finally, it was electropolished in a mixture of 80% acetic acid and 20% perchloric acid at a voltage of 27 V for 7 seconds to produce the pretreated welding wire. Titanium carbide plating: Prepare titanium carbide electroplating solution, the preparation method is as follows: Graphene oxide, nickel salt, and Tween 80 were added to deionized water, ultrasonically dispersed for 1 hour, and then titanium carbide and boric acid were added, and ultrasonic dispersion was continued for another hour to obtain an electroplating solution; The usage ratio of the graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 3g:200g:1L:80g:30g; The amount of Tween 80 used is 5% of the mass of graphene oxide.

[0086] The graphene oxide is prepared by Hummers oxidation method.

[0087] The above nickel salt is nickel chloride.

[0088] The electroplating process parameters of the titanium carbide layer are as follows: current density 3A / dm 2 , electroplating time 0.5h, electroplating temperature 45℃, stirring speed 300r / min.

[0089] S18: Plating a nickel layer on the surface of the welding wire to obtain a target product, i.e., a multi-element nickel alloy composite welding wire with low thermal crack sensitivity.

[0090] Example 4 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, Preferably, RE is a mixture of Y, Sm, Gd, and Nd in a mass ratio of 6:1:1:1.

[0091] Example 5 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, Preferably, RE is Y.

[0092] Example 6 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, The preferred weight ratio of Al to Ti is 2.0:1.

[0093] Example 7 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, The preferred weight ratio of Al to Ti is 4.0:1.

[0094] Example 8 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, Preferably, the weight percentage of titanium carbide in the composite welding wire is 0.1%.

[0095] Example 9 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, Preferably, the weight percentage of titanium carbide in the composite welding wire is 1.0%.

[0096] Example 10 The rest is the same as in Example 1, except that: A method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, in S17, The usage ratio of graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 1 g:200 g:1 L:60 g:30 g.

[0097] Example 11 The rest is the same as in Example 1, except that: A method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, in S17, The usage ratio of graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 5g:200g:1L:100g:30g.

[0098] The following comparative examples are compared with Example 1: Comparative Example 1 The rest is the same as in Example 1, except that: A low-hot-crack-sensitivity multi-element nickel alloy composite welding wire comprises a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.03%, Si: 0.15%, Cr: 28.5%, Fe: 9.0%, Mn: 0.9%, Co: 1.4%, Mo: 4.6%, B: 0.003%, Al + Ti: 0.17%, Zr: 0.010%, Nb: 1.6%, Ta: 0.3%, Sn: 0.8%, RE: 0.25%, S: 0.002%, P: 0.002%, and Ni as the balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0099] Comparative Example 2 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, The weight ratio of Al to Ti is 1.0:1.

[0100] Comparative Example 3 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, The weight ratio of Al to Ti is 5.0:1.

[0101] Comparative Example 4 The rest is the same as in Example 1, except that: A low-hot-crack-sensitivity multi-element nickel alloy composite welding wire comprises a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.03%, Si: 0.15%, Cr: 29.5%, Fe: 9.0%, Mn: 0.6%, Co: 1.4%, Mo: 4.6%, B: 0.003%, Al + Ti: 0.17%, Zr: 0.010%, Nb: 1.6%, Ta: 0.3%, Sn: 0.8%, RE: 0.25%, S: 0.002%, P: 0.002%, and Ni as the balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0102] That is, the weight ratio of Mn to Si is 4.0:1.

[0103] Comparative Example 5 The rest is the same as in Example 1, except that: A low-hot-crack-sensitivity multi-element nickel alloy composite welding wire comprises a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.03%, Si: 0.15%, Cr: 29.5%, Fe: 9.0%, Mn: 1.2%, Co: 1.4%, Mo: 4.6%, B: 0.003%, Al + Ti: 0.17%, Zr: 0.010%, Nb: 1.6%, Ta: 0.3%, Sn: 0.8%, RE: 0.25%, S: 0.002%, P: 0.002%, and Ni as the balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

[0104] That is, the weight ratio of Mn to Si is 8.0:1.

[0105] Comparative Example 6 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, The coating is a nickel layer; that is, no titanium carbide coating is performed; that is, the weight percentage of titanium carbide in the composite welding wire is 0%.

[0106] Comparative Example 7 The rest is the same as in Example 1, except that: In a low thermal crack sensitivity multi-element nickel alloy composite welding wire formula, The weight percentage of titanium carbide in the composite welding wire is controlled to be 1.5% by the thickness of the titanium carbide coating.

[0107] Comparative Example 8 The rest is the same as in Example 1, except that: In a method for preparing a multi-element nickel alloy composite welding wire with low thermal crack sensitivity, in S17, The usage ratio of graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 0 g: 200 g: 1 L: 80 g: 30 g; that is, no graphene oxide is added.

[0108] The nickel alloy welding materials obtained in the examples and comparative examples were used to perform TIG / flat-down welding on the ASME SB-168 UNS N06690 alloy material, and the post-weld heat treatment parameters were 610° C. and 24 h of holding temperature.

[0109] The physical properties of the low thermal crack sensitivity multi-component nickel alloy composite welding wires prepared in the examples of the present invention and the comparative examples were measured, and the results are shown in Table 1.

[0110] Table 1 Physical test performance of each embodiment It can be observed from Examples 1-11 that the low thermal crack sensitivity of the multi-element nickel alloy composite welding wire of the present invention is reflected in its excellent mechanical properties and corrosion resistance at high temperatures, which can be reflected in the absence of defects such as cracks in the weld at high temperatures.

[0111] It can be observed from Example 1 and Comparative Examples 1-5 that the addition of appropriate amounts of Cr and Mo to the low thermal crack sensitivity multi-element nickel alloy composite welding wire of the present invention achieves a solid solution strengthening effect, improving its high temperature corrosion resistance and thermal strength; Al and Ti have a certain strengthening and toughening effect on the alloy; Mn and Si have an excellent deoxidation effect, reducing grain boundary embrittlement, improving weld strength, and at the same time improving high temperature strength and other functions; It can be observed from Example 1 and Comparative Examples 6-8 that they have excellent mechanical properties and low corrosion at high temperatures, indicating that the titanium carbide coating, as a ceramic material, is directly introduced into the weld during welding, which can effectively improve the weld strength and the weld is free of defects such as cracks at high temperatures; graphene oxide also plays an important positive role in improving weld strength.

[0112] In summary, the low thermal crack sensitivity multi-element nickel alloy composite welding wire of the present invention has excellent mechanical properties and corrosion resistance.

[0113] The test method is as follows: (1) Crack resistance: Observe whether there are visible cracks on the weld strip, and if the specimen is intact after bending or the length of a single crack is ≤1.5mm, it is recorded as "OK"; otherwise, if there are visible cracks and the length of a single crack after bending is greater than 1.5mm, it is recorded as "NG".

[0114] (2) Mechanical properties test: The room temperature mechanical properties and high temperature mechanical properties tests of the welded joints were carried out at room temperature and 350 °C respectively in accordance with GB / T2651 2008 “Tensile test method for welded joints”.

[0115] (3) Corrosion rate: The corrosion resistance test was carried out using the ASTM G28 A method, and the test time was 120 h.

[0116] With the above-described preferred embodiments of the present invention as a guide, and with reference to the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of this invention. The technical scope of this invention is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A low thermal crack sensitivity multicomponent nickel alloy composite welding wire, characterized by: The invention comprises a welding wire and a coating, wherein the welding wire comprises the following powder raw materials in parts by weight: C: 0.01-0.05%, Si: 0.10-0.20%, Cr: 28.5-30.5%, Fe: 7.0-11.0%, Mn: ≤1.0%, Co: 1.0-2.0%, Mo: 4.0-5.0%, B: 0.001-0.005%, Al+Ti: 0.1-0.2%, Zr: 0.005-0.020%, Nb: 1.0-2.0%, Ta: 0.1-0.4%, Sn: 0.5-1.0%, RE: 0.20-0.30%, S: <0.005%, P: <0.005%, and Ni as the balance; and The coating is titanium carbide layer and nickel layer from inside to outside.

2. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 1, characterized in that: The total amount of Cr and Mo is not less than 33.5%.

3. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 1, characterized in that: The weight ratio of Al to Ti is (2.0-4.0):

1.

4. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 1, characterized in that: The weight ratio of Mn to Si is (5.0-7.0):

1.

5. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 1, characterized in that: The RE is one or more of Y, Ce, Sm, Gd, and Nd.

6. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 1, characterized in that: The weight percentage of titanium carbide in the composite welding wire is 0.1-1.0%.

7. A method for preparing a multicomponent nickel alloy composite welding wire with low thermal crack sensitivity, characterized in that: The following steps are involved: S11: Raw materials are weighed according to the mass percentage of the formula and processed to obtain a uniform and refined mixed powder; S12: placing the mixed powder into a smelting furnace for smelting, performing high-temperature refining, low-temperature refining, and then remelting and refining, and casting into an alloy ingot; S13: After annealing the alloy ingot, forging and rolling are performed to prepare alloy wire rods; S14: performing multiple drawing-annealing steps on the alloy wire rod after pretreatment; S15: Processing the alloy wire into the required size and performing solution-aging treatment; S16: pickling the alloy wire; coating; S17: After pre-treating the surface, a titanium carbide layer is plated to obtain a welding wire; and S18: Plating a nickel layer on the surface of the welding wire to obtain a target product, i.e., a multi-element nickel alloy composite welding wire with low thermal crack sensitivity.

8. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 7, characterized in that: The preparation method of the electroplating solution of the titanium carbide layer is: Graphene oxide, nickel salt, and surfactant were added to deionized water, ultrasonically dispersed for 1 hour, and then titanium carbide and boric acid were added, and ultrasonic dispersion was continued for another hour to obtain an electroplating solution; The usage ratio of the graphene oxide, nickel salt, deionized water, titanium carbide, and boric acid is 1-5g:200g:1L:60-100g:30g; The amount of the surfactant is 5% of the mass of graphene oxide; The nickel salt is nickel sulfate and / or nickel chloride; and The titanium carbide particle size is 5-10 μm.

9. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 8, characterized in that: The surfactant is a nonionic surfactant.

10. The low thermal crack sensitivity multicomponent nickel alloy composite welding wire according to claim 8, characterized in that: The graphene oxide is prepared by Hummers oxidation method.

Images