Welding manufacturing method for complex thin-wall stainless steel component

Abstract

The invention relates to the technical field of stainless steel welding, and particularly discloses a complex thin-wall stainless steel component welding manufacturing method which comprises the steps of S1, material selection, S2, process design, S3, welding preparation, S4, welding treatment and S5, post-welding treatment. During welding, nano materials are evenly distributed in a welding seam, the yield strength and the tensile strength of the welding seam are improved, micro holes in the welding seam can be filled with the nano particles due to the small size of the nano particles, the compactness and the overall strength of the welding seam are improved, and the high hardness characteristic of the nano materials is transmitted into the welding seam; the overall hardness and wear resistance of the welding seam are improved, the microstructure of the welding seam is improved through the nanometer materials, the possibility of intergranular corrosion and pitting corrosion is reduced, the grain structure of the welding seam can be refined in the welding process through addition of the nanometer materials, and the welding defects such as air holes, cracks and slag inclusion are reduced; the welding seam has higher toughness due to the uniform distribution and grain refinement effect of the nano material in the welding seam.

Description

Technical Field

[0001] The invention belongs to the technical field of stainless steel welding, and in particular relates to a welding manufacturing method for a complex thin-walled stainless steel component. Background Art

[0002] In the field of stainless steel processing, the welding and manufacturing of thin-walled stainless steel components has always been a technical challenge. Although traditional welding methods, such as TIG (tungsten inert gas hydrogen arc welding) and MIG (molten inert gas hydrogen arc welding), can meet basic welding needs, they often face problems such as insufficient weld strength, poor density, and low wear resistance during the welding of complex thin-walled stainless steel components.

[0003] In recent years, with the rapid development of nanotechnology, the application of nanomaterials in the field of welding has gradually attracted attention. With its unique physical and chemical properties, nanomaterials provide new ideas for the innovation of welding technology. Especially in the welding and manufacturing of complex thin-walled stainless steel components, the application of nanomaterials shows great potential.

[0004] Adding nanomaterials, such as nanometal particles and nanooxides, to welds can effectively improve the yield strength and tensile strength of welds. The small size of nanoparticles enables them to penetrate into the microscopic pores in the weld, filling and reinforcing the weld structure, thereby increasing the density and overall strength of the weld. In addition, the high hardness characteristics of nanomaterials can also be transferred to the weld, further improving the overall hardness and wear resistance of the weld.

[0005] However, the uniform distribution of nanomaterials in the weld is the key to achieving its enhancement effect. Traditional welding methods often make it difficult to ensure the uniform dispersion of nanomaterials in the weld, thus affecting the quality and performance of the weld. Therefore, developing new welding processes to achieve uniform distribution of nanomaterials in the weld has become an important way to improve the quality and performance of the weld.

[0006] This technology uses special welding processes and equipment to evenly disperse nanomaterials in the welding pool, ensuring uniform distribution of nanomaterials in the weld. At the same time, by optimizing welding parameters and the amount of nanomaterials added, the strength, density and wear resistance of the weld are significantly improved. This technology is not only suitable for the welding and manufacturing of complex thin-walled stainless steel components, but can also be widely used in the welding process of other metal materials, with broad application prospects and huge economic value.

[0007] In view of this, the inventor proposes a welding manufacturing method for complex thin-walled stainless steel components to solve the above problems. Summary of the invention

[0008] The object of the present invention is to provide a welding manufacturing method for complex thin-walled stainless steel components to solve the problems raised in the above background technology.

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] A welding manufacturing method for a complex thin-walled stainless steel component, comprising:

[0011] S1. Material selection: Choose thin-walled stainless steel materials, including 304 or 316L stainless steel. Use pickling or mechanical grinding to clean the materials and remove the oxide scale, oil stains and dust on the surface of the materials.

[0012] S2. Process design: Draw detailed design drawings according to the use requirements of the components, clarify the size, tolerance and assembly requirements of each component, and conduct welding process assessment tests to determine the appropriate welding parameters and processes;

[0013] S3, welding preparation, use special fixtures to stabilize the stainless steel material and preheat it;

[0014] S4, welding treatment, using a nano material feeder, adding nano alumina or nano silicon carbide powder to the molten pool at 0.7% of the weld metal, using a TIG welder, welding to ensure that the nano material is evenly distributed in the weld;

[0015] S5. Post-weld treatment: After welding is completed, use a stainless steel brush or chemical cleaning agent to remove welding slag and oxides, clean the weld, use sandpaper or a polishing machine to gradually grind from coarse to fine, and use electrolytic polishing equipment with a mixture of phosphoric acid and sulfuric acid to obtain a finished complex thin-walled stainless steel component.

[0016] Preferably, the pickling in S1 is carried out using a mixture of 10% to 20% nitric acid and 1% to 2% hydrofluoric acid, and the mechanical grinding uses a stainless steel special grinding wheel or sandpaper with a particle size between 80 and 120 meshes.

[0017] Preferably, the design drawings in S2 are drawn in detail using CAD software, with dimensional tolerances marked, and welding parameters including welding current, voltage, speed, and shielding gas flow.

[0018] Preferably, the temperature of the preheating treatment in S3 is controlled at 100-150 degrees Celsius.

[0019] Preferably, in S3, an I-type or V-type groove is used according to the thickness of the component.

[0020] Preferably, the particle size of the nano material in S4 is 20-50 nm, and spot welding is performed before welding, with a spot welding spacing of 50-100 mm.

[0021] Preferably, the welding conditions are current 50-120A, voltage 10-15V, welding speed 2-4mm / s, shielding gas 99.99% pure argon and flow rate 12-15L / min.

[0022] Preferably, the nano material feeder comprises a workpiece, a welding pool, a weld, a TIG arc, a welding gun housing, a tungsten electrode, a high-pressure argon gas flow for feeding nano powder, a shielding gas argon, a flow rate control valve, and a filler wire. During the welding process, the TIG welder generates an arc, which acts on the welding area of ​​the workpiece to form a welding pool. At the same time, the non-melting tungsten electrode serves as an electrode to provide the current required by the arc. In order to protect the welding area from air oxidation, a shielding argon gas is used for gas protection.

[0023] The high-pressure argon gas for delivering nano powder is responsible for delivering nano alumina or nano silicon carbide powder into the welding gun housing at a certain speed and pressure. An air flow channel is designed inside the welding gun housing to ensure that the nano powder can flow stably under the carrying of high-pressure argon gas;

[0024] The flow rate control valve uses the Bernoulli principle to adjust the air flow velocity and pressure distribution to further accurately control the flow rate and distribution of the nano powder at the powder feeder outlet, ensuring that the nano powder can enter the welding pool evenly and continuously and be fully mixed with the weld metal;

[0025] During the welding process, the filler wire is fed into the molten pool to form a weld together with the nano powder and the molten pool metal.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The present invention uses nanomaterials to be evenly distributed in the weld, thereby improving the yield strength and tensile strength of the weld. The small size of the nanoparticles enables them to fill the microscopic pores in the weld, increasing the density and overall strength of the weld. The high hardness characteristics of the nanomaterials are transmitted to the weld, thereby improving the overall hardness and wear resistance of the weld. The nanomaterials improve the microstructure of the weld and reduce the possibility of intergranular corrosion and pitting. The addition of nanomaterials can refine the grain structure of the weld during the welding process and reduce welding defects such as pores, cracks and slag inclusions. The uniform distribution of nanomaterials in the weld and the effect of refining the grains make the weld have higher toughness, can better absorb and disperse stress, and reduce the risk of brittle fracture.

[0028] (2) The solution of the present invention combined with nanomaterials to enhance weld technology significantly improves the mechanical properties, corrosion resistance and overall quality of the weld, making complex thin-walled stainless steel components perform better under various harsh working conditions. These beneficial effects make this technology have broad application prospects in high-demand industrial fields, such as aerospace, automobile manufacturing, marine engineering and chemical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A flow chart of a welding manufacturing method for a complex thin-walled stainless steel component of the present invention;

[0030] Figure 2 It is a schematic structural diagram of the nano material feeder of the present invention.

[0031] In the figure: 1. workpiece; 11. welding pool; 12. weld; 2. TIG arc; 3. welding gun housing; 4. tungsten electrode; 5. high-pressure argon flow for nano-powder; 6. shielding gas argon; 7. flow rate control valve; 8. filling wire. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Embodiment 1:

[0034] See also Figure 1 and Figure 2 As shown, a welding manufacturing method for a complex thin-walled stainless steel component comprises:

[0035] S1. Material selection: Choose thin-walled stainless steel materials, including 304 or 316L stainless steel. Use pickling or mechanical grinding to clean the materials and remove the oxide scale, oil stains and dust on the surface of the materials.

[0036] S2. Process design: Draw detailed design drawings according to the use requirements of the components, clarify the size, tolerance and assembly requirements of each component, and conduct welding process assessment tests to determine the appropriate welding parameters and processes;

[0037] S3, welding preparation, use special fixtures to stabilize the stainless steel material and preheat it;

[0038] S4, welding treatment, using a nano material feeder, adding nano alumina or nano silicon carbide powder to the molten pool at 0.7% of the weld metal, using a TIG welder, welding to ensure that the nano material is evenly distributed in the weld;

[0039] S5. Post-weld treatment: After welding is completed, use a stainless steel brush or chemical cleaning agent to remove welding slag and oxides, clean the weld, use sandpaper or a polishing machine to gradually grind from coarse to fine, and use electrolytic polishing equipment with a mixture of phosphoric acid and sulfuric acid to obtain a finished complex thin-walled stainless steel component.

[0040] Specifically, the pickling in S1 is performed using a mixture of 12% nitric acid and 2% hydrofluoric acid, and the mechanical grinding uses a stainless steel special grinding wheel or sandpaper with a particle size of about 100 meshes.

[0041] Specifically, the design drawings in S2 are drawn in detail using CAD software, with dimension tolerances marked, and welding parameters including welding current, voltage, speed, and shielding gas flow.

[0042] Specifically, the temperature of the preheating treatment in S3 is controlled at 120 degrees Celsius.

[0043] Specifically, in S3, an I-type groove is adopted according to the thickness of the component.

[0044] Specifically, the particle size of the nanomaterial in S4 is 30 nm, and spot welding is performed before welding, with a spot welding spacing of 80 mm.

[0045] Specifically, the welding conditions are as follows: current 80A, voltage 12V, welding speed 3mm / s, shielding gas 99.99% pure argon gas, and flow rate 15L / min.

[0046] The nano material feeder comprises a workpiece 1, a welding pool 11, a weld 12, a TIG arc 2, a welding gun housing 3, a tungsten electrode 4, a high-pressure argon gas flow 5 for feeding nano powder, a shielding gas argon gas 6, a flow rate control valve 7, and a filler wire 8. During the welding process, the TIG welder generates an arc 2, which acts on the welding area of ​​the workpiece 1 to form a welding pool 11. At the same time, the non-melting tungsten electrode 4 serves as an electrode to provide the current required by the arc. In order to protect the welding area from air oxidation, a shielding argon gas 6 is used for gas protection.

[0047] The nano powder delivery high-pressure argon gas 5 is responsible for delivering the nano-aluminum oxide or nano-silicon carbide powder into the welding gun housing 3 at a certain speed and pressure. The welding gun housing 3 is designed with an air flow channel to ensure that the nano-powder can flow stably under the carrying of the high-pressure argon gas;

[0048] The flow rate control valve 7 uses the Bernoulli principle to further accurately control the flow rate and distribution of the nano powder at the outlet of the powder feeder by adjusting the air flow velocity and pressure distribution, ensuring that the nano powder can enter the welding molten pool 11 evenly and continuously and be fully mixed with the weld metal;

[0049] During the welding process, the filler wire 8 is fed into the molten pool to form a weld 12 together with the nano powder and the molten pool metal. Due to the addition of nano powder, the microstructure and properties of the weld metal can be significantly improved, such as improving hardness, wear resistance and corrosion resistance.

[0050] From the above, it can be seen that the present invention adds nanomaterials during the welding process, thereby enhancing the mechanical properties of the weld, and the weld strength, hardness and wear resistance are significantly improved. The nanomaterials improve the microstructure of the weld and improve the corrosion resistance. The nanomaterials fill the micropores in the molten pool, reduce the generation of cracks, and improve the integrity of the weld.

[0051] Embodiment 2:

[0052] refer to Figure 1 and Figure 2 As shown, a welding manufacturing method for a complex thin-walled stainless steel component comprises:

[0053] S1. Material selection: Choose thin-walled stainless steel materials, including 304 or 316L stainless steel. Use pickling or mechanical grinding to clean the materials and remove the oxide scale, oil stains and dust on the surface of the materials.

[0054] S2. Process design: Draw detailed design drawings according to the use requirements of the components, clarify the size, tolerance and assembly requirements of each component, and conduct welding process assessment tests to determine the appropriate welding parameters and processes;

[0055] S3, welding preparation, use special fixtures to stabilize the stainless steel material and preheat it;

[0056] S4, welding process, using TIG welding machine to perform welding;

[0057] S5. Post-weld treatment: After welding is completed, use a stainless steel brush or chemical cleaning agent to remove welding slag and oxides, clean the weld, use sandpaper or a polishing machine to gradually grind from coarse to fine, and use electrolytic polishing equipment with a mixture of phosphoric acid and sulfuric acid to obtain a finished complex thin-walled stainless steel component.

[0058] Specifically, the pickling in S1 is performed using a mixture of 12% nitric acid and 2% hydrofluoric acid, and the mechanical grinding uses a stainless steel special grinding wheel or sandpaper with a particle size of about 100 meshes.

[0059] Specifically, the design drawings in S2 are drawn in detail using CAD software, with dimension tolerances marked, and welding parameters including welding current, voltage, speed, and shielding gas flow.

[0060] Specifically, the temperature of the preheating treatment in S3 is controlled at 120 degrees Celsius.

[0061] Specifically, in S3, an I-type groove is adopted according to the thickness of the component.

[0062] Specifically, spot welding is performed before welding, and the spot welding spacing is 80 mm.

[0063] Specifically, the welding conditions are as follows: current 80A, voltage 12V, welding speed 3mm / s, shielding gas 99.99% pure argon gas, and flow rate 15L / min.

[0064] Specifically, the steps for using the nanomaterial feeder are the same as those in Example 1.

[0065] The stainless steel components prepared in Example 1 and Example 2 were tested, wherein Example 1 was an experimental group with the addition of nanomaterials, and Example 2 was a control group without the addition of nanomaterials;

[0066] The test steps are as follows:

[0067] 1. Nondestructive testing:

[0068] Radiographic flaw detection is used, that is, X-rays or y-rays are used to irradiate the welded joints of the stainless steel sheets in Example 1 and Example 2 under the same conditions and parameters to check the internal defects of the welds, and record the number of pores, cracks, and slag inclusions;

[0069] 2. Mechanical properties test:

[0070] 1. Tensile test:

[0071] Prepare specimens that meet standards, usually including requirements such as size, shape and processing accuracy.

[0072] The specimen is installed on the tensile testing machine and a gradually increasing tensile force is applied until the specimen breaks. The data during the tensile process is recorded to evaluate the tensile strength, yield strength and other mechanical properties of the stainless steel sheet.

[0073] 2. Hardness test:

[0074] Select a Vickers hardness tester, select the same test points on the stainless steel sheets in Example 1 and Example 2, and perform the test according to the operating procedures of the hardness tester, record and evaluate the hardness values ​​of the test points, so as to evaluate the wear resistance and processing performance of the stainless steel sheets;

[0075] 3. Corrosion resistance test (salt spray test):

[0076] 1. Prepare the sample: Cut the stainless steel sheets in Example 1 and Example 2 into samples that meet the standards, and perform necessary surface treatment, such as cleaning and degreasing;

[0077] 2. Place the samples: Place the samples in the salt spray test chamber, making sure that the samples do not touch or overlap each other;

[0078] 3. Set parameters: According to GB / T2423.17-2008 and GB / T10125 standards, set the parameters of the salt spray test, such as salt solution concentration, pH value, temperature, test time, etc.;

[0079] 4. Conduct the test: Start the salt spray test chamber to allow the salt spray to settle evenly on the sample. During the test, regularly check and record the corrosion conditions of the sample;

[0080] 4. Toughness test (Charpy impact test):

[0081] 1. Prepare the sample: Prepare a metal sample with a U-shaped or V-shaped notch according to the standard;

[0082] 2. Set parameters: According to the standard, set the test temperature (usually room temperature), pendulum nominal striking energy and other parameters;

[0083] 3. Conduct the test: Install the specimen on the Charpy impact tester and release the pendulum to strike the specimen. Record and calculate the impact absorption energy of the specimen.

[0084] The test data is as follows:

[0085] 1. Nondestructive testing (number of defects)

[0086] Control group (no nanomaterials):

[0087] Number of pores: 10 / 100mm;

[0088] Number of cracks: 5 / 100mm;

[0089] Number of slag inclusions: 8 / 100mm;

[0090] Experimental group (adding nanomaterials):

[0091] Number of pores: 2 / 100mm;

[0092] Number of cracks: 1 / 100mm;

[0093] Number of slag inclusions: 3 / 100mm;

[0094] 2. Mechanical properties test

[0095] Tensile test:

[0096] Control group (no nanomaterial): yield strength: 310MPa, tensile strength: 580MPa;

[0097] Experimental group (adding nanomaterials): yield strength: 360MPa, tensile strength: 630MPa;

[0098] Hardness test:

[0099] Control group (no nanomaterial): Vickers hardness: 220HV;

[0100] Experimental group (adding nanomaterials): Vickers hardness: 260HV;

[0101] 3. Corrosion resistance test (salt spray test, 48 hours)

[0102] Control group (no nanomaterial): number of corrosion points: 15 / 100mm2, corrosion depth: 0.08mm;

[0103] Experimental group (adding nanomaterials): number of corrosion points: 5 / 100mm2, corrosion depth: 0.03mm;

[0104] 4. Toughness test (Charpy impact test)

[0105] Control group (no nanomaterials): impact energy: 45J;

[0106] Experimental group (adding nanomaterials): impact energy: 55J;

[0107] As can be seen from the above, the use of nanomaterials evenly distributed in the weld improves the yield strength and tensile strength of the weld. The small size of the nanoparticles enables them to fill the microscopic pores in the weld, increasing the density and overall strength of the weld. The high hardness characteristics of the nanomaterials are transmitted to the weld, improving the overall hardness and wear resistance of the weld. The nanomaterials improve the microstructure of the weld and reduce the possibility of intergranular corrosion and pitting. The addition of nanomaterials can refine the grain structure of the weld during welding and reduce welding defects such as pores, cracks and slag inclusions. The uniform distribution of nanomaterials in the weld and the role of refining grains make the weld have higher toughness, can better absorb and disperse stress, and reduce the risk of brittle fracture.

[0108] The solution of combining nanomaterials to enhance weld technology significantly improves the mechanical properties, corrosion resistance and overall quality of the weld, making complex thin-walled stainless steel components perform better under various harsh working conditions. These beneficial effects make this technology have a wide range of application prospects in high-demand industrial fields, such as aerospace, automobile manufacturing, marine engineering and chemical equipment.

[0109] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0110] In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other.

[0111] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A welding method for manufacturing complex thin-walled stainless steel components, characterized in that: The following steps are involved: S1. Material selection: Choose thin-walled stainless steel materials, including 304 or 316L stainless steel. Use pickling or mechanical grinding to clean the materials and remove the oxide scale, oil stains and dust on the surface of the materials. S2. Process design: Draw detailed design drawings according to the use requirements of the components, clarify the size, tolerance and assembly requirements of each component, and conduct welding process assessment tests to determine the appropriate welding parameters and processes; S3, welding preparation, use special fixtures to stabilize the stainless steel material and preheat it; S4, welding treatment, using a nano material feeder, adding nano alumina or nano silicon carbide powder to the molten pool at 0.7% of the weld metal, using a TIG welder, welding to ensure that the nano material is evenly distributed in the weld; S5. Post-weld treatment: After welding is completed, use a stainless steel brush or chemical cleaning agent to remove welding slag and oxides, clean the weld, use sandpaper or a polishing machine to gradually grind from coarse to fine, and use electrolytic polishing equipment with a mixture of phosphoric acid and sulfuric acid to obtain a finished complex thin-walled stainless steel component.

2. The welding method for manufacturing a complex thin-walled stainless steel component according to claim 1, characterized in that: In S1, the pickling is carried out using a mixture of 10% to 20% nitric acid and 1% to 2% hydrofluoric acid, and the mechanical grinding uses a stainless steel special grinding wheel or sandpaper with a particle size between 80 and 120 meshes.

3. The welding method for manufacturing a complex thin-walled stainless steel component according to claim 1, characterized in that: The design drawings in S2 are drawn in detail using CAD software, with dimension tolerances marked, and welding parameters including welding current, voltage, speed, and shielding gas flow.

4. The welding method for manufacturing a complex thin-walled stainless steel component according to claim 1, characterized in that: The temperature of the preheating treatment in S3 is controlled at 100-150 degrees Celsius.

5. The welding method for manufacturing a complex thin-walled stainless steel component according to claim 1, characterized in that: In S3, I-type or V-type groove is used according to the thickness of the component.

6. The welding manufacturing method of a complex thin-walled stainless steel component according to claim 1, characterized in that: The particle size of nanomaterials in S4 is 20-50nm. Spot welding is performed before welding, and the spot welding spacing is 50-100mm.

7. The welding method for manufacturing a complex thin-walled stainless steel component according to claim 1, characterized in that: The welding conditions are current 50-120A, voltage 10-15V, welding speed 2-4mm / s, shielding gas 99.99% pure argon and flow rate 12-15L / min.

8. The welding manufacturing method of a complex thin-walled stainless steel component according to claim 1, characterized in that: The nano material feeder comprises a workpiece (1), a welding molten pool (11), a weld (12), a TIG arc (2), a welding gun housing (3), a tungsten electrode (4), a high-pressure argon gas flow (5) for delivering nano powder, a protective argon gas (6), a flow rate control valve (7), and a filler wire (8). During the welding process, the TIG welding machine generates an arc (2), which acts on the welding area of ​​the workpiece (1) to form a welding molten pool (11). At the same time, the non-melting tungsten electrode (4) serves as an electrode to provide the current required by the arc. In order to protect the welding area from air oxidation, protective argon gas (6) is used for gas protection; The nano powder delivery high-pressure argon gas (5) is responsible for delivering the nano aluminum oxide or nano silicon carbide powder into the welding gun housing (3) at a certain speed and pressure. The welding gun housing (3) is designed with an air flow channel inside to ensure that the nano powder can flow stably under the carrying of the high-pressure argon gas. The flow rate control valve (7) uses the Bernoulli principle to adjust the air flow velocity and pressure distribution to further accurately control the flow rate and distribution of the nano powder at the outlet of the powder feeder, thereby ensuring that the nano powder can evenly and continuously enter the welding molten pool (11) and be fully mixed with the weld metal; During the welding process, a filler wire (8) is fed into the molten pool to form a weld (12) together with the nano powder and the molten pool metal.

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