A method of welding a stainless steel weld
By preparing high-purity ER308L stainless steel welding wire and combining it with tungsten inert gas welding technology, the problem of insufficient high-temperature plasticity of stainless steel welds in existing technologies has been solved, and good plasticity of welds in high-temperature environments has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA IRON & STEEL RESEARCH INSTITUTE GROUP CO LTD
- Filing Date
- 2023-12-13
- Publication Date
- 2026-08-04
AI Technical Summary
The high-temperature plasticity of 308L stainless steel welds in the existing technology is low, which cannot meet the high-temperature environment requirements of in-core components in nuclear power equipment.
ER308L stainless steel welding wire is prepared by smelting high-purity welding wire raw materials in a vacuum furnace and then hot-forming and cold-forming. Combined with tungsten inert gas welding technology, the heat input parameters are set within the range of 8 to 18 KJ/cm. The preset welding process parameters are used to generate the weld metal that meets the preset requirements, ensuring that the weld elongation is ≥32% at 350℃.
It improves the high-temperature plasticity of stainless steel welds, meets the high-temperature environment requirements of reactor internals in nuclear power equipment, and ensures that the welds have good elongation and plasticity at 350℃.
Smart Images
Figure CN117483921B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of welding, and more specifically to a welding method for stainless steel welds. Background Technology
[0002] With the rapid development of the national economy, energy demand has been expanding, and energy has become one of the main factors affecting the stable economic development of countries around the world. Compared with thermal power, nuclear power has the advantages of producing no carbon dioxide, sulfur dioxide, or carbon and nitrogen oxides. Stainless steel is widely used in nuclear power equipment because it can adapt to the special environment inside nuclear power plants. Taking pressurized water reactors as an example, more than 90% of the materials in equipment and components that only come into contact with the primary coolant are made of steel and nickel-based alloys, and stainless steel accounts for 80% to 90% of these materials. 304 / 304H austenitic stainless steel is widely used in reactor internals, and common welding methods include argon arc welding, shielded metal arc welding, and submerged arc welding. The safety level of reactor internals meets the requirements of LS level for non-pressure-bearing mechanical equipment, seismic resistance category I, and quality assurance classification Q1. Their working environment is extremely harsh, operating not only under high temperature, high pressure, and strong radiation, but also enduring long-term scouring by the coolant and the vibrations caused by scouring. To ensure the reactor internals maintain good performance throughout the design life of the nuclear power plant, guarantee safe reactor operation, and preserve the integrity and safety of the reactor structure, the materials selected for the internals are extremely important. Welded joints are the weakest points in the reactor internals structure. Their welding typically uses 308L alloy welding materials. With the advancement of third-generation nuclear power technology, the size and weight of reactor internals have increased significantly, placing higher demands on the high-temperature plasticity of 308L stainless steel TIG welds at 350℃. Current technology shows relatively low high-temperature plasticity of 308L stainless steel welds, with a typical weld elongation of around 25%. Summary of the Invention
[0003] This application provides a welding method for stainless steel welds, which solves the technical problem of low high-temperature plasticity of 308L stainless steel welds in the prior art.
[0004] In view of the above problems, this application provides a welding method for stainless steel welds.
[0005] A first aspect of this application provides a method for welding stainless steel welds, the method comprising:
[0006] Obtain a target stainless steel welding wire that meets the preset element content weight percentage, wherein the target stainless steel welding wire is obtained by smelting high-purity welding wire raw materials in a vacuum furnace under an argon-rich environment and then hot forming and cold forming, wherein the target stainless steel welding wire is ER308L stainless steel welding wire.
[0007] Set the heat input parameters within the preset parameter range to generate the target heat input parameters;
[0008] Under the target heat input parameters, tungsten inert gas welding is used in conjunction with the target stainless steel welding wire to weld at the workpiece according to the preset welding process parameters to generate deposited metal, wherein the deposited metal must meet the preset deposited metal requirements.
[0009] The target stainless steel weld is obtained after the deposited metal cools and crystallizes at the workpiece being welded.
[0010] Preferably, the high-purity welding wire raw materials include chromium, nickel, carbon, silicon, manganese, sulfur, phosphorus, nitrogen, copper, molybdenum, vanadium, cobalt, and iron, and need to meet preset purity requirements, wherein the preset purity requirements are pure iron greater than or equal to 99.8%, pure nickel ≥ 99%, and pure chromium ≥ 99%.
[0011] Preferably, the preset element content by weight percentage of the target stainless steel welding wire is: chromium 18.00~22.00, nickel 9.50~11.50, carbon ≤0.030, silicon 0.10~0.60, manganese 1.00~2.00, sulfur ≤0.005, phosphorus ≤0.007, nitrogen 0.001~0.070, copper ≤0.08, molybdenum ≤0.50, vanadium ≤0.05, cobalt ≤0.05, and the remainder is iron.
[0012] Preferably, the chromium equivalent of the target stainless steel welding wire is chromium% + molybdenum% + (1.5 × silicon%) + (0.5 × niobium%), and the nickel equivalent is nickel% + 0.52 manganese% + 30 carbon% + 30 nitrogen%, wherein the chromium equivalent and nickel equivalent must meet the preset equivalent requirements.
[0013] Preferably, the preset equivalent requirements are chromium equivalent ∈ (19.00~22.50), nickel equivalent ∈ (12.00~14.00), and chromium equivalent / nickel equivalent = (1.38~1.62).
[0014] Preferably, the target stainless steel welding wire has a specification of φ0.8mm to 2.00mm.
[0015] Preferably, the preset parameter range is 8 to 18 KJ / cm.
[0016] Preferably, the preset welding process parameters are: welding current 80-220A, welding voltage 12-14V, welding speed 14-18cm / min, interpass temperature <100℃, shielding gas is pure argon, and gas flow rate is 10L / min.
[0017] Preferably, the preset weld metal is required to have a δ-ferrite content of 3% to 8% and an elongation of ≥32% at 350°C.
[0018] Preferably, the target stainless steel welding wire is suitable for tungsten inert gas welding of 304 stainless steel.
[0019] One or more technical solutions provided in this application have at least the following technical effects or advantages:
[0020] To obtain a target stainless steel welding wire that meets the preset element content weight percentage, high-purity welding wire raw materials need to be smelted in an argon-rich environment and then hot-formed and cold-formed. The target stainless steel welding wire is ER308L stainless steel welding wire, which needs to meet the preset element content requirements. To generate the target thermal input parameters, the thermal input parameters need to be set within a preset parameter range. Under the target thermal input parameters, tungsten inert gas welding is used in conjunction with the target stainless steel welding wire to weld at the workpiece. During the welding process, preset welding process parameters are applied to the actual welding operation to generate weld metal that meets the preset weld metal requirements. After the weld metal cools and solidifies at the workpiece, the target stainless steel weld is obtained. This solves the technical problem of low high-temperature plasticity of 308L stainless steel welds in the prior art and achieves the technical effect of good high-temperature plasticity of stainless steel welds. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of a welding method for stainless steel welds provided in an embodiment of this application. Detailed Implementation
[0023] This application provides a welding method for stainless steel welds, which solves the technical problem of low high-temperature plasticity of 308L stainless steel welds in the prior art.
[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0025] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or server that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or modules that are not explicitly listed or that are inherent to such process, method, product, or device.
[0026] Example 1
[0027] like Figure 1 As shown in the embodiment of this application, a welding method for stainless steel welds is provided, wherein the method includes:
[0028] Obtain a target stainless steel welding wire that meets the preset element content weight percentage, wherein the target stainless steel welding wire is obtained by smelting high-purity welding wire raw materials in a vacuum furnace under an argon-rich environment and then hot forming and cold forming, wherein the target stainless steel welding wire is ER308L stainless steel welding wire.
[0029] To obtain the target stainless steel welding wire that meets the preset element content by weight percentage, high-purity welding wire raw material must first be processed in a vacuum furnace and smelted in an argon-rich environment. This step ensures that the element content in the raw material is effectively purified and uniformly distributed. Next, the molten welding wire raw material undergoes hot forming and cold forming processes. The hot forming process ensures the stability of the welding wire's shape and dimensions, while cold forming further enhances its structural strength and stability. Through these steps, the target stainless steel welding wire, made of ER308L stainless steel, is obtained. ER308L stainless steel welding wire possesses excellent corrosion resistance and high-temperature performance.
[0030] Furthermore, the high-purity welding wire raw materials include chromium, nickel, carbon, silicon, manganese, sulfur, phosphorus, nitrogen, copper, molybdenum, vanadium, cobalt, and iron, and need to meet preset purity requirements, wherein the preset purity requirements are pure iron greater than or equal to 99.8%, pure nickel ≥ 99%, and pure chromium ≥ 99%.
[0031] To obtain high-quality welded joints and meet application requirements, high-purity welding wire raw materials must meet preset purity requirements. These preset purity requirements are: pure iron ≥ 99.8%, pure nickel ≥ 99%, and pure chromium ≥ 99%.
[0032] Furthermore, the preset element content by weight percentage of the target stainless steel welding wire is as follows: chromium 18.00~22.00, nickel 9.50~11.50, carbon ≤0.030, silicon 0.10~0.60, manganese 1.00~2.00, sulfur ≤0.005, phosphorus ≤0.007, nitrogen 0.001~0.070, copper ≤0.08, molybdenum ≤0.50, vanadium ≤0.05, cobalt ≤0.05, and the remainder is iron.
[0033] Chromium is the main element in austenitic stainless steel, improving its corrosion resistance and heat resistance. The addition of nickel increases its toughness and reduces its coefficient of thermal expansion. Carbon is the primary element controlling the hardness and toughness of stainless steel, while silicon enhances its corrosion resistance and high-temperature mechanical properties. The addition of elements such as manganese, molybdenum, vanadium, and cobalt further improves the strength and corrosion resistance of stainless steel.
[0034] Furthermore, the chromium equivalent in the target stainless steel welding wire is equal to chromium% + molybdenum% + (1.5 × silicon%) + (0.5 × niobium%), and the nickel equivalent is equal to nickel% + 0.52 manganese% + 30 carbon% + 30 nitrogen%, wherein the chromium equivalent and nickel equivalent must meet the preset equivalent requirements.
[0035] The chromium and nickel equivalents in the target stainless steel welding wire are calculated based on preset equivalent requirements. Chromium equivalent refers to the total content of elements with chromium as the main component, and nickel equivalent refers to the total content of elements with nickel as the main component.
[0036] Furthermore, the preset equivalent requirements are chromium equivalent ∈ (19.00~22.50), nickel equivalent ∈ (12.00~14.00), and chromium equivalent / nickel equivalent = (1.38~1.62).
[0037] The chromium equivalent / nickel equivalent ratio reflects the relative content of chromium and nickel in stainless steel welding wire, and this ratio also affects the properties of stainless steel. Within this preset equivalent range, a chromium equivalent / nickel equivalent ratio can ensure that the stainless steel welding wire has good corrosion resistance and mechanical properties.
[0038] Furthermore, the target stainless steel welding wire has a specification of φ0.8mm~2.00mm.
[0039] The diameter of stainless steel welding wire ranges from 0.8 mm to 2.00 mm.
[0040] Set the heat input parameters within the preset parameter range to generate the target heat input parameters;
[0041] Heat input parameters are a crucial variable in the welding process, referring to the amount of heat input to the weld. The magnitude of this heat directly affects the quality and outcome of the weld. Therefore, the heat input parameters need to be set within a preset range to generate the target heat input parameters. This preset range is determined based on welding process requirements and factors such as the material and thickness of the workpiece. Within this range, the heat input parameters need to be adjusted and optimized according to actual conditions. Generally, the range of the preset parameter range needs to be determined through experimentation and experience, and appropriate heat input parameters are selected to achieve the best welding results. Generating the target heat input parameters can be achieved by adjusting parameters such as welding current, voltage, and welding speed. For example, increasing the welding current increases the heat input, while increasing the welding speed decreases the heat input. By adjusting these parameters, precise control of the heat input can be achieved, thereby generating the target heat input parameters.
[0042] Furthermore, the preset parameter range is 8–18 KJ / cm.
[0043] During welding, to achieve optimal weld quality and results, the heat input parameter should not be lower than 8 kJ / cm or higher than 18 kJ / cm. Within this range, adjusting the heat input parameter controls the temperature, flow, and solidification behavior of the molten pool, thereby affecting the microstructure and properties of the deposited metal. If the heat input parameter is too low, the molten pool temperature may be insufficient, affecting the fusion of the deposited metal and the weld quality. If the heat input parameter is too high, the molten pool temperature may be excessively high, causing overheating, oxidation, and evaporation of the deposited metal, which will also affect the weld quality.
[0044] Furthermore, the preset welding process parameters are: welding current 80-220A, welding voltage 12-14V, welding speed 14-18cm / min, interpass temperature <100℃, shielding gas is pure argon, and gas flow rate is 10L / min.
[0045] Welding current is the heat generated by the current passing through the tungsten electrode and welding wire. It determines the temperature of the molten pool and the melting rate of the deposited metal. A suitable welding current ensures the stability of the molten pool and the quality of the weld. Welding voltage is the electric field strength of the arc. It determines the energy required to ionize the gas and sustain the arc. A suitable welding voltage ensures the stability of the arc and the effectiveness of the shielding gas. Welding speed is the speed at which the welding torch moves during the welding operation. It determines the filling speed of the deposited metal and the width of the weld. A suitable welding speed ensures the filling of the deposited metal and the quality of the weld. Interpass temperature refers to the temperature between adjacent weld passes, reflecting the temperature change of the deposited metal during welding. Excessively high interpass temperatures can lead to overheating, oxidation, and evaporation of the deposited metal, while excessively low temperatures can lead to excessively rapid solidification of the molten pool and slag inclusions in the weld. Shielding gas is the gas used to protect the molten pool and the welding area, preventing oxidation and contamination of the deposited metal. Pure argon is a common shielding gas that effectively protects the molten pool and reduces the formation of oxides and porosity. Gas flow rate refers to the flow rate of argon gas through the tungsten inert gas (TIG) welding equipment, which affects the effectiveness and quality of the shielding gas.
[0046] Under the target heat input parameters, tungsten inert gas welding is used in conjunction with the target stainless steel welding wire to weld at the workpiece according to the preset welding process parameters to generate deposited metal, wherein the deposited metal must meet the preset deposited metal requirements.
[0047] Under the target heat input parameters, and according to the preset welding process parameters, tungsten inert gas (TIG) welding technology is used in conjunction with the target stainless steel welding wire to perform welding operations on the workpiece. TIG welding is a commonly used welding method that uses argon gas as a shielding gas, and heats and melts the welding wire and the base metal through an electric arc to form deposited metal.
[0048] To meet the preset requirements for weld metal, precise adjustment and control of welding process parameters are necessary. For example, parameters such as welding current, voltage, and welding speed can be adjusted to control the temperature, flow, and solidification behavior of the molten pool, thereby obtaining weld metal that meets the preset requirements. Simultaneously, attention must be paid to protecting the weld metal during the welding process. Argon, as a protective gas, can effectively prevent oxidation and contamination of the molten pool, ensuring the quality of the weld metal. Furthermore, the current and voltage of the tungsten electrode must be carefully controlled to avoid overheating and radioactive contamination.
[0049] Furthermore, the preset requirements for the deposited metal are that the δ-ferrite content is 3% to 8% and the elongation at 350°C is ≥32%.
[0050] δ-ferrite content is an important chemical component in weld metal. Ferrite is an α-Fe solid solution, possessing good plasticity and toughness. The preset requirement of 3% to 8% ferrite content is to ensure that the weld metal has certain strength and plasticity. Within this range, the higher the ferrite content, the better the strength and plasticity of the weld metal. Elongation ≥32% at 350℃ is an important indicator for measuring the plasticity of weld metal. Elongation refers to the ratio of the tensile force a material can withstand during stretching to its original length. At 350℃, the weld metal needs to have sufficient elongation to ensure that it can withstand certain deformation and stress during use. The preset elongation requirement ensures that the weld metal has good plasticity and processing performance at high temperatures.
[0051] Furthermore, the target stainless steel welding wire is suitable for tungsten inert gas welding of 304 stainless steel.
[0052] The target stainless steel weld is obtained after the deposited metal cools and crystallizes at the workpiece being welded.
[0053] The target stainless steel weld is obtained after the deposited metal cools and solidifies at the workpiece. The target stainless steel weld is formed by welding the target stainless steel welding wire to the base metal. In this process, the cooling and solidification of the deposited metal at the workpiece is crucial. Cooling and solidification determine the microstructure and physical properties of the deposited metal. To obtain the target stainless steel weld, the cooling rate and solidification temperature need to be carefully controlled. Generally, a faster cooling rate and a lower solidification temperature result in finer grains and higher hardness. However, an excessively fast cooling rate can lead to stress concentration and crack formation. Therefore, the cooling rate needs to be adjusted and optimized according to the actual situation to obtain the best weld microstructure and properties.
[0054] In summary, the embodiments of this application have at least the following technical effects:
[0055] To obtain a target stainless steel welding wire that meets the preset element content weight percentage, high-purity welding wire raw materials need to be smelted in an argon-rich environment and then hot-formed and cold-formed. The target stainless steel welding wire is ER308L stainless steel welding wire, which needs to meet the preset element content requirements. To generate the target thermal input parameters, the thermal input parameters need to be set within a preset parameter range. Under the target thermal input parameters, tungsten inert gas welding is used in conjunction with the target stainless steel welding wire to weld at the workpiece. During the welding process, preset welding process parameters are applied to the actual welding operation to generate weld metal that meets the preset weld metal requirements. After the weld metal cools and solidifies at the workpiece, the target stainless steel weld is obtained. This solves the technical problem of low high-temperature plasticity of 308L stainless steel welds in the prior art and achieves the technical effect of good high-temperature plasticity of stainless steel welds.
[0056] Example 2
[0057] In another possible implementation, the ER308L stainless steel argon arc welding wire is composed of chromium, nickel, carbon, silicon, manganese, sulfur, phosphorus, nitrogen, copper, molybdenum, vanadium, cobalt, and iron.
[0058] The elements in the welding wire, by weight percentage, are as follows: chromium 19.10%, nickel 10.34%, carbon 0.0052%, silicon 0.20%, manganese 1.60%, sulfur 0.002%, phosphorus 0.004%, nitrogen 0.025%, copper 0.005%, molybdenum 0.10%, vanadium 0.0056%, cobalt 0.005%, with the remainder being iron. The chromium equivalent is 19.50, the nickel equivalent is 12.09, and the chromium equivalent / nickel equivalent ratio is 1.61. The welding parameters are: welding current 190A, welding voltage 12.5V, welding speed 16.5cm / min, and welding heat input 8.6KJ / cm. The shielding gas is pure argon with a flow rate of 10L / min. The ferrite content is 7.6%.
[0059] Example 3
[0060] The difference from Example 2 is that the weight percentage of each element in the welding wire is as follows: chromium 19.39%, nickel 10.36%, carbon 0.011%, silicon 0.22%, manganese 1.89%, sulfur 0.002%, phosphorus 0.005%, nitrogen 0.041%, copper 0.012%, molybdenum 0.006%, vanadium 0.050%, cobalt 0.040%, and the remainder is iron. The chromium equivalent is 19.72%, the nickel equivalent is 12.90%, and the chromium equivalent / nickel equivalent = 1.52. The welding parameters are: welding current 190A, welding voltage 12.5V, welding speed 16.5cm / min, and welding heat input 8.6KJ / cm. The shielding gas is pure argon with a gas flow rate of 10L / min. The ferrite content is 6%.
[0061] Example 4
[0062] The difference from Example 2 is that the elements in the welding wire, by weight percentage, are as follows: chromium 19.17%, nickel 10.85%, carbon 0.010%, silicon 0.22%, manganese 1.83%, sulfur 0.004%, phosphorus 0.005%, nitrogen 0.061%, copper 0.012%, molybdenum 0.006%, vanadium 0.050%, cobalt 0.040%, with the remainder being iron. The chromium equivalent is 19.55%, the nickel equivalent is 13.63%, and the chromium equivalent / nickel equivalent = 1.43. The welding parameters are: welding current 190A, welding voltage 12.5V, welding speed 16.5cm / min, and welding heat input 8.6KJ / cm. The shielding gas is pure argon with a gas flow rate of 10L / min. The ferrite content is 3.5%.
[0063] Comparative Example 1
[0064] The difference from Example 2 is that the elements in the welding wire, by weight percentage, are as follows: chromium 19.71%, nickel 9.34%, carbon 0.021%, silicon 0.34%, manganese 1.47%, sulfur 0.005%, phosphorus 0.009%, nitrogen 0.010%, copper 0.005%, molybdenum 0.01%, vanadium 0.020%, cobalt 0.035%, with the remainder being iron. The chromium equivalent is 20.23, the nickel equivalent is 11.00, and the chromium equivalent / nickel equivalent = 1.83. The welding parameters are: welding current 190A, welding voltage 12.5V, welding speed 16.5cm / min, and welding heat input 8.6KJ / cm. The shielding gas is pure argon with a flow rate of 10L / min. The ferrite content is 11.8%.
[0065] Using ER308L stainless steel welding wires from Examples 2, 3, and 4 and Comparative Example 1, tungsten inert gas (TIG) welding was performed on 304 stainless steel as the base material. The heat input was ≤18 KJ / cm, and welding experiments were conducted while ensuring approximately the same current, voltage, and welding speed. Tensile samples were taken to test the mechanical properties of the deposited metal, and the test results are shown in Table 1. In these examples, while maintaining strength, the elongation at 350℃ reached over 32%, indicating that the ER308L welding wire developed in this invention has excellent performance and good high-temperature plasticity.
[0066] Table 1 Tensile properties at 350°C for Examples and Comparative Examples
[0067]
[0068] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments have been described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than that shown in the embodiments and still achieve the desired result. Additionally, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.
[0069] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
[0070] This specification and accompanying drawings are merely illustrative examples of this application and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Therefore, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.
Claims
1. A welding method for stainless steel welds, characterized in that, The method includes: Obtain a target stainless steel welding wire that meets the preset element content weight percentage, wherein the target stainless steel welding wire is obtained by smelting high-purity welding wire raw materials in a vacuum furnace under an argon-rich environment and then hot forming and cold forming, wherein the target stainless steel welding wire is ER308L stainless steel welding wire. Set the heat input parameters within the preset parameter range to generate the target heat input parameters; Under the target heat input parameters, tungsten inert gas welding is used in conjunction with the target stainless steel welding wire to weld at the workpiece according to the preset welding process parameters to generate deposited metal, wherein the deposited metal must meet the preset deposited metal requirements. After the deposited metal cools and crystallizes at the workpiece being welded, the target stainless steel weld is obtained; The target stainless steel welding wire has the following preset element content by weight percentage: chromium 18.00~22.00, nickel 9.50~11.50, carbon ≤0.030, silicon 0.10~0.60, manganese 1.00~2.00, sulfur ≤0.005, phosphorus ≤0.007, nitrogen 0.001~0.070, copper ≤0.08, molybdenum ≤0.50, vanadium ≤0.05, cobalt ≤0.05, and the remainder is iron; The preset parameter range is 8–18 KJ / cm; The preset welding process parameters are: welding current 80-220A, welding voltage 12-14V, welding speed 14-18cm / min, interpass temperature <100℃, shielding gas is pure argon, and gas flow rate is 10L / min. The preset requirements for the deposited metal are: δ-ferrite content of 3% to 8% and elongation of ≥32% at 350°C.
2. The welding method for stainless steel welds as described in claim 1, characterized in that, The high-purity welding wire raw materials include chromium, nickel, carbon, silicon, manganese, sulfur, phosphorus, nitrogen, copper, molybdenum, vanadium, cobalt, and iron, and need to meet preset purity requirements, wherein the preset purity requirements are that the purity of iron is ≥99.8%, the purity of nickel is ≥99%, and the purity of chromium is ≥99%.
3. The welding method for stainless steel welds as described in claim 1, characterized in that, The nickel equivalent in the target stainless steel welding wire is calculated as: nickel% + 0.52 manganese% + 30 carbon% + 30 nitrogen%. The nickel equivalent must meet a preset equivalent requirement, which is a nickel equivalent ∈ (12.00~14.00).
4. The welding method for stainless steel welds as described in claim 1, characterized in that, The target stainless steel welding wire has a specification of φ0.8mm~2.00mm.
5. The welding method for stainless steel welds as described in claim 1, characterized in that, The target stainless steel welding wire is suitable for tungsten inert gas welding of 304 stainless steel.