High-toughness and high-efficiency submerged arc welding flux and preparation method thereof

Abstract

The application belongs to the technical field of welding materials, and specifically provides a high-toughness and high-efficiency submerged-arc flux, which comprises, in percentage by mass, 15-25% of magnesite, 5-10% of bauxite, 10-20% of wollastonite, 11-19% of fluorite, 3-8% of rutile, 2-6% of cryolite, 3-5% of ferrosilicon, 6-15% of iron powder, 6-8% of silicon-zirconium alloy, 0.3-0.8% of Cr, 1-2% of ferrotitanium, 0.5-2.5% of boron iron, 0.2-0.5% of vanadium-niobium alloy and 0.5-1.0% of strontium carbonate. The high-toughness and high-efficiency submerged-arc flux has high toughness and excellent crack resistance, the content of diffusible hydrogen in the deposited metal is low, the requirement of ultralow hydrogen is met, the radiographic examination meets the requirement of level 1 in GB / T37910.1, the welding efficiency is high, the performance of resisting large linear energy is excellent, and the submerged-arc flux can be used for single-wire and double-wire welding. In combination with H10Mn2, EH14 and other welding wires, the welding requirement of wind power thick plates Q345C, D, E, F and other materials can be met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of welding materials, and particularly relates to a high-toughness and high-efficiency submerged arc flux and a preparation method thereof. BACKGROUND

[0002] Wind power generation is an important renewable clean energy generation method, and is also one of the strategic industries that countries around the world pay great attention to and develop. It plays a crucial role in energy and environmental protection. As of the end of 2022, the newly added wind power hoisting capacity was 498.3 million kilowatts, and the cumulative wind power hoisting capacity reached 396 million kilowatts, with a year-on-year growth of 11.2%. At the same time, domestic welding materials are increasingly used in the wind power industry. In the aspect of flux matching, SJ101 flux is still mostly used in China, and there are still many problems in the production and manufacturing process of thick plates in the wind power industry, such as a large number of rework caused by cracks in thick plate welding, inability to perform high-energy welding, low weld flaw detection qualification rate, and insufficient low-temperature impact toughness of joints. Therefore, the application provides a high-toughness and high-efficiency submerged arc flux that can be used for thick plates in the wind power industry. SUMMARY

[0003] The application aims to overcome the problems of low weld flaw detection qualification rate and insufficient low-temperature impact toughness of joints in the prior art.

[0004] Therefore, the application provides a high-toughness and high-efficiency submerged arc flux. The submerged arc flux comprises, in terms of mass percentage, 15-25% of magnesia, 5-10% of bauxite, 10-20% of wollastonite, 11-19% of fluorite, 3-8% of rutile, 2-6% of cryolite, 3-5% of ferrosilicon, 6-22% of iron powder, 6-8% of silicon-zirconium alloy, 0.3-0.8% of Cr, 1-2% of titania, 0.5-2.5% of boron iron, 0.2-0.5% of vanadium-niobium alloy, and 0.5-1.0% of strontium carbonate.

[0005] Specifically, the content of S in the submerged arc flux is less than or equal to 0.020%; and the content of P is less than or equal to 0.025%.

[0006] Specifically, the particle size of the submerged arc flux is 12-60 mesh, and the mass percentages of 12-18 mesh, 18-20 mesh, 20-40 mesh, and 40-60 mesh are 45%, 40%, 10%, and 5%, respectively.

[0007] Specifically, the alkalinity of the submerged arc flux is 1.6-2.0.

[0008] The application further provides a preparation method of the high-toughness and high-efficiency submerged arc flux.

[0009] (1) The raw materials of the submerged arc flux are crushed and sieved, and then weighed and prepared according to the mass percentage;

[0010] (2) Iron powder is mixed with bauxite uniformly, and after sieving, resin is used for bonding, sintering, sieving, and standby;

[0011] (3) The remaining raw materials are mixed, and a bonding agent is added, and after being stirred uniformly, the product after sintering is mixed with the product of step (2) to obtain the submerged arc flux.

[0012] Specifically, in step (2), the iron powder and bauxite are mixed and sieved through an 80-mesh sieve, and 1-5% resin is used for bonding by mass percentage.

[0013] Specifically, in step (2), the sintering temperature is 200-250℃, and the sintering time is 2-4h, and after sintering, the product is sieved through a 40-mesh sieve.

[0014] Specifically, in step (3), the amount of the bonding agent is 8-12% of the mass of the remaining raw materials.

[0015] Specifically, the bonding agent is a mixture of lithium water glass and sodium water glass, and the mass percentage of the mixture of lithium water glass and sodium water glass is 1:1.

[0016] Specifically, in step (3), the sintering temperature is 850-880℃, and the sintering time is 1-3h.

[0017] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0018] The high-toughness and high-efficiency submerged arc flux provided by the present application reduces the content of sulfur, phosphorus and impurities in the raw materials of the flux through raw material purification technology, improves the stability of acicular ferrite in the weld under large line energy conditions by controlling the appropriate Mg, N and V in the weld, improves the deposition efficiency by adding iron powder, refines the grains by adding trace elements of Sr, Ti, B and part of rare earth elements, disperses the strengthening to prevent the diffusion of cracks, and improves the crack resistance. In combination with H10Mn2, EH14 and other welding wires, the welding requirements of wind power thick plates Q345C, D, E, F and other materials can be met. The tensile strength is above 550MPa, the yield strength is above 420MPa, the yield ratio is ≤0.86, the single-wire welding at-40℃ is above 170J, and the single-wire welding at-60℃ is above 100J. The welding efficiency is high, the resistance to large line energy is excellent, and it can be used for double-wire welding. The low-temperature impact toughness is stable at 250℃, which is above 120J at-40℃ and above 60J at-60℃. In addition to the high toughness, the welding wire also has excellent crack resistance. When double-wire welding a 100mm thick plate, the CTOD value at-10℃ is not less than 0.30mm. The diffusion hydrogen content in the deposited metal is as low as 4ml / 100g or less, meeting the super-low hydrogen requirement, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. DETAILED DESCRIPTION

[0019] The technical solutions in the present application will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Although the representative embodiments of the present application have been described in detail, those skilled in the art will understand that various modifications and changes can be made to the present application without departing from the scope of the present application. Therefore, the scope of the present application should not be limited to the embodiments, but should be defined by the appended claims and their equivalents.

[0020] The present application provides a high-toughness and high-efficiency submerged arc flux, which comprises, in percentage by mass, 15-25% of magnesia, 5-10% of bauxite, 10-20% of wollastonite, 11-19% of fluorite, 3-8% of rutile, 2-6% of cryolite, 3-5% of ferrosilicon, 6-22% of iron powder, 6-8% of silicon-zirconium alloy, 0.3-0.8% of Cr, 1-2% of ferrotitanium, 0.5-2.5% of boron iron, 0.2-0.5% of vanadium-niobium alloy, and 0.5-1.0% of strontium carbonate. The S in the submerged arc flux is ≤0.020%, and the P is ≤0.025%. The alkalinity is controlled at 1.6-2.0. The particle size is 12-60 mesh, wherein the mass percentage of 12-18 mesh, 18-20 mesh, 20-40 mesh and 40-60 mesh is 45%, 40%, 10% and 5%, respectively.

[0021] The present application also provides a preparation method of the high-toughness and high-efficiency submerged arc flux, which comprises the following steps:

[0022] (1) crushing and sieving the raw materials of the submerged arc flux, weighing and preparing the materials according to the percentage by mass;

[0023] (2) mixing the iron powder and the bauxite uniformly, passing through an 80-mesh sieve, using 1-5% of resin as a binder according to the percentage by mass, low-temperature sintering at 200-250°C for 2-4h, passing through a 40-mesh sieve, and preparing for use;

[0024] (3) mixing the remaining raw materials, adding 8-12% of a binder according to the percentage by mass, stirring uniformly, high-temperature sintering at 850-880°C for 1-3h, mixing the product with the product of step (2), and obtaining the submerged arc flux. The binder is a mixture of lithium water glass and sodium water glass, and the mixing percentage by mass of the lithium water glass and the sodium water glass is 1:1.

[0025] The effect of the high-toughness and high-efficiency submerged arc flux of the present application is studied below through specific embodiments.

[0026] Embodiment 1

[0027] The present embodiment provides a high-toughness and high-efficiency submerged arc flux, which comprises, in percentage by mass,

[0028] Magnesite 19%; bauxite 10%; wollastonite 15%; fluorite 12%; 98 rutile 3%; ice 6%; 75 ferrosilicon 3%; iron powder 21.9%, silicon-zirconium alloy 7%; metal Cr 0.4%; ferrotitanium 1.0%; boron iron 0.8%; vanadium-niobium alloy 0.2%; strontium carbonate 0.7%.

[0029] S in the flux: 0.015%; P: 0.020%.

[0030] The alkalinity of the submerged arc flux is 1.65, and the particle size is 12-60 mesh, wherein the mass percentage of 12-18 mesh, 18-20 mesh, 20-40 mesh and 40-60 mesh is 45%, 40%, 10% and 5%.

[0031] The high-toughness and high-efficiency submerged arc flux provided by the embodiment is prepared by the following steps:

[0032] (1) The raw materials of the submerged arc flux are coarsely crushed, finely crushed, and powdered, etc. Processed into powders of different standard particle sizes, and after sieving, the powders are weighed and mixed according to the formula;

[0033] (2) Mix the iron powder and bauxite uniformly, pass through an 80-mesh sieve, and use 3% resin to bond, sinter at 200-250°C for 2.5h, pass through a 40-mesh sieve, and reserve;

[0034] (3) Mix the remaining raw materials, and add 10% binder, mix thoroughly, and sinter at 850-880°C for 1.5h, then mix the product with the product of step (2) to obtain the submerged arc flux.

[0035] The binder is a mixture of lithium water glass and sodium water glass in a mass ratio of 1:1.

[0036] The submerged arc flux provided by the embodiment is subjected to a deposited metal experiment, and the experiment uses EH14 double-wire welding. The mechanical property results are shown in Table 1, the diffusible hydrogen content in the deposited metal is 4ml / 100g, which meets the ultra-low hydrogen requirement, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The mechanical property and CTOD(-10°C) experimental results of the 100mm thick butt joint are shown in Table 2.

[0037] Example 2:

[0038] The embodiment provides a high-toughness and high-efficiency submerged arc flux, which comprises, by mass percentage:

[0039] Magnesite 17%; bauxite 9%; wollastonite 19%; fluorite 17%; 98 rutile 5%; cryolite 2%; 75 ferrosilicon 4%; iron powder 17.1%, silicon-zirconium alloy 6%; metal Cr 0.5%; ferrotitanium 1.4%; boron iron 1.0%; vanadium-niobium alloy 0.4%; strontium carbonate 0.6%.

[0040] S in the flux: 0.016%; P: 0.019%.

[0041] The alkalinity of the submerged arc flux is 1.70, and the particle size is 12-60 mesh, wherein the mass percentages of 12-18 mesh, 18-20 mesh, 20-40 mesh, and 40-60 mesh are 45%, 40%, 10%, and 5%, respectively.

[0042] The high-toughness and high-efficiency submerged arc flux provided in the embodiment is prepared by the following steps:

[0043] (1) The raw materials of the submerged arc flux are coarsely crushed, finely crushed, and ground into powder, and the powder is sieved and weighed according to the formula;

[0044] (2) The iron powder and bauxite are mixed uniformly, sieved through an 80-mesh sieve, and then 2% resin is used for bonding at a mass percentage, and low-temperature sintering is performed at 200-250°C for 2h, and then the product is sieved through a 40-mesh sieve for standby use;

[0045] (3) The remaining raw materials are mixed, and 11% binder is added at a mass percentage, and the mixture is stirred uniformly, and then sintering is performed at 850-880°C for 2h, and then the product is mixed uniformly with the product of step (2) to obtain the submerged arc flux.

[0046] The binder is a mixture of lithium water glass and sodium water glass at a mass percentage of 1:1.

[0047] The submerged arc flux provided in the embodiment is subjected to a deposited metal experiment, and the experiment adopts EH14 double-wire welding, the mechanical property results are shown in Table 1, the diffusible hydrogen content in the deposited metal is 3.8 ml / 100g, which meets the ultra-low hydrogen requirement, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The mechanical property and CTOD (-10°C) experimental results of the 100mm thick butt joint are shown in Table 2.

[0048] Example 3:

[0049] The embodiment provides a high-toughness and high-efficiency submerged arc flux, which comprises, by mass percentage:

[0050] Magnesite 23%; bauxite 9%; wollastonite 12%; fluorite 15%; 98 rutile 7%; cryolite 5%; 75 ferrosilicon 5%; iron powder 11%, silicon-zirconium alloy 8%; metal Cr 0.6%; ferrotitanium 1.6%; boron iron 1.5%; vanadium-niobium alloy 0.3%; strontium carbonate 1.0%.

[0051] S in the flux: 0.014%; P: 0.019%.

[0052] The alkalinity of the submerged arc flux is 1.82, and the particle size is 12-60 mesh, wherein the mass percentage of 12-18 mesh, 18-20 mesh, 20-40 mesh and 40-60 mesh is 45%, 40%, 10% and 5%.

[0053] The high-toughness and high-efficiency submerged arc flux provided in the embodiment is prepared by the following steps:

[0054] (1) The raw materials of the submerged arc flux are coarsely crushed, finely crushed, and powdered, etc. process to process powders of different standard particle sizes, and after sieving, the powders are weighed and mixed according to the formula;

[0055] (2) The iron powder and bauxite are mixed uniformly, sieved through an 80-mesh sieve, and then 3.5% resin is used for bonding, low-temperature sintering at 200-250°C for 3h, sieving through a 40-mesh sieve, and standby;

[0056] (3) The remaining raw materials are mixed, 9% binder is added according to the mass percentage, and the mixture is stirred uniformly, then the product is mixed uniformly with the product of step (2) after sintering at 850-880°C for 2.5h, and the submerged arc flux is obtained.

[0057] The binder is a mixture of lithium water glass and sodium water glass in a mass ratio of 1:1.

[0058] The submerged arc flux provided in the embodiment is subjected to a deposited metal experiment, and the experiment uses EH14 double-wire welding. The mechanical property results are shown in Table 1, the diffusible hydrogen content in the deposited metal is 3.2 ml / 100g, which meets the ultra-low hydrogen requirement, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The mechanical property and CTOD(-10°C) experimental results of the 100mm thick butt joint are shown in Table 2.

[0059] Example 4:

[0060] The embodiment provides a high-toughness and high-efficiency submerged arc flux, which comprises, by mass percentage:

[0061] Magnesite 25%; bauxite 6%; wollastonite 18%; fluorite 14%; 98 rutile 4%; cryolite 5%; 75 ferrosilicon 4%; iron powder 10.3%; silicon-zirconium alloy 8%; metallic Cr 0.7%; titanium iron 1.8%; boron iron 2.0%; vanadium-niobium alloy 0.4%; strontium carbonate 0.8%.

[0062] S in the flux: 0.015%; P: 0.020%.

[0063] The alkalinity of the submerged arc flux is 1.93, and the particle size is 12-60 mesh, wherein the mass percentage of 12-18 mesh, 18-20 mesh, 20-40 mesh and 40-60 mesh is 45%, 40%, 10% and 5%.

[0064] The high-toughness and high-efficiency submerged arc flux provided by the embodiment is prepared by the following steps:

[0065] (1) The raw materials of the submerged arc flux are coarsely crushed, finely crushed, and powdered, etc. to process powders of different standard particle sizes, which are sieved and then weighed and mixed according to the formula;

[0066] (2) The iron powder and bauxite are uniformly mixed, sieved through an 80-mesh sieve, and then 5% resin is used for bonding at a mass percentage, low-temperature sintering at 200-250°C for 3h, sieving through a 40-mesh sieve, and standby;

[0067] (3) The remaining raw materials are mixed, 11% binder is added at a mass percentage, and the mixture is fully stirred and uniformly mixed, and then the product is sintered at 850-880°C for 2.5h to obtain the submerged arc flux.

[0068] The binder is a mixture of lithium water glass and sodium water glass at a mass percentage of 1:1.

[0069] The submerged arc flux provided by the embodiment is subjected to a deposited metal experiment, and the experiment adopts EH14 double-wire welding. The mechanical property results are shown in Table 1. The diffusible hydrogen content in the deposited metal is 3.5ml / 100g, which meets the ultra-low hydrogen requirement, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The mechanical property and CTOD(-10°C) experimental results of the 100mm thick butt joint are shown in Table 2.

[0070] Example 5:

[0071] The embodiment provides a high-toughness and high-efficiency submerged arc flux, which comprises, by mass percentage:

[0072] Magnesite 23%; bauxite 5%; wollastonite 14%; fluorite 19%; 98 rutile 7%; cryolite 5%; 75 ferrosilicon 4%; iron powder 9.7%; silicon-zirconium alloy 7%; metallic Cr 0.8%; titanium iron 1.8%; boron iron 2.5%; vanadium-niobium alloy 0.5%; strontium carbonate 0.7%.

[0073] The S in the flux is 0.016%, and the P is 0.021%.

[0074] The alkalinity of the submerged arc flux is 2.0, and the particle size is 12-60 mesh, wherein the mass percentage of 12-18 mesh, 18-20 mesh, 20-40 mesh and 40-60 mesh is 45%, 40%, 10% and 5%.

[0075] The high-toughness and high-efficiency submerged arc flux provided by the embodiment is prepared by the following steps:

[0076] (1) Coarse crushing, fine crushing, powdering and other processes are performed on each raw material of the submerged arc flux to process the powder into different standard particle sizes, and the powder is sieved and weighed according to the formula;

[0077] (2) The iron powder and bauxite are uniformly mixed, sieved through an 80-mesh sieve, and then 4% resin is used for bonding at a mass percentage, low-temperature sintering at 200-250°C for 4h, sieving through a 40-mesh sieve, and standby;

[0078] (3) The remaining raw materials are mixed, 12% binder is added at a mass percentage, and the mixture is fully stirred and uniformly mixed, and then the product is mixed with the product of step (2) after sintering at 850-880°C for 3h to obtain the submerged arc flux.

[0079] The binder is a mixture of lithium water glass and sodium water glass at a mass percentage of 1:1.

[0080] The submerged arc flux provided by the embodiment is subjected to a deposited metal experiment, and the experiment adopts EH14 double-wire welding. The mechanical property results are shown in Table 1, the diffusion hydrogen content in the deposited metal is 3.0 ml / 100g, which meets the ultra-low hydrogen requirement, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The mechanical property and CTOD (-10°C) experimental results of the 100mm thick butt joint are shown in Table 2.

[0081] Table 1 Mechanical properties of deposited metal

[0082]

[0083] Table 2 Mechanical properties and CTOD (-10°C) experimental results of 100mm thick butt joint

[0084]

[0085]

[0086]

[0087] As shown in Table 1 and Table 2, the submerged arc flux provided by the application has tensile strength of 550 MPa or more, yield strength of 420 MPa or more, yield ratio of 0.86 or less, and elongation of more than 25%; the welding efficiency is high, the performance of resisting large line energy is excellent, it can be used for single-wire and double-wire welding, the low-temperature impact toughness at 250℃ is stable, the impact toughness at-40℃ is more than 120J, and the impact toughness at-60℃ is more than 60J. The welding wire has excellent crack resistance in addition to high toughness, the CTOD value at-10℃ is not less than 0.30mm when double-wire welding; the content of diffusible hydrogen in the deposited metal is as low as 4ml / 100g or less, which meets the requirement of ultra-low hydrogen, and the radiographic inspection meets the requirement of level 1 in GB / T 37910.1.

[0088] The above examples are only illustrative of the application, and do not constitute a limitation on the protection scope of the application, and any design identical or similar to the application falls within the protection scope of the application.

Claims

1. A high-toughness and high-efficiency submerged arc flux, characterized in that, The submerged arc flux comprises, in percentage by mass, 15-25% of magnesia, 5-10% of bauxite, 10-20% of wollastonite, 11-19% of fluorite, 3-8% of rutile, 2-6% of cryolite, 3-5% of ferrosilicon, 6-22% of iron powder, 6-8% of silicon-zirconium alloy, 0.3-0.8% of Cr, 1-2% of ferrotitanium, 0.5-2.5% of boron iron, 0.2-0.5% of vanadium-niobium alloy, and 0.5-1.0% of strontium carbonate; the high-toughness and high-efficiency submerged arc flux is used in combination with an EH14 welding wire.

2. The high-toughness and high-efficiency submerged arc flux according to claim 1, characterized in that: The submerged arc flux has S≤0.020% and P≤0.025%.

3. The high-toughness and high-efficiency submerged arc flux as claimed in claim 1, wherein: The particle size of the submerged arc flux is 12-60 mesh.

4. The high ductility high efficiency submerged arc flux as claimed in claim 1, wherein: The alkalinity of the submerged arc flux is 1.6-2.

0.

5. The method of producing a high-toughness and high-efficiency submerged-arc flux according to any one of claims 1 to 4, characterized by, The method comprises the following steps: (1) crushing and sieving each raw material of the submerged arc flux, weighing and preparing materials according to percentage by mass; (2) mixing and uniformly bonding the iron powder and the bauxite, sieving, sintering, sieving, and preparing for use; (3) mixing the remaining raw materials, adding a bonding agent, uniformly stirring, mixing the product of step (2) after sintering, and obtaining the submerged arc flux.

6. The method of claim 5, wherein the high-toughness and high-efficiency submerged arc flux is prepared by the steps of: In step (2), the iron powder and the bauxite are mixed and sieved through an 80-mesh sieve, and 1-5% of a resin bonding agent is used according to percentage by mass. ​ 7. The preparation method of the high-toughness and high-efficiency submerged arc welding flux as described in claim 5, characterized in that: In step (2), the sintering temperature is 200-250℃, the sintering time is 2-4h, and the product is sieved through a 40-mesh sieve after sintering.

8. The method of claim 5, wherein the high-toughness and high-efficiency submerged arc flux is prepared by the steps of: In step (3), the amount of the bonding agent is 8-12% of the mass of the remaining raw materials. ​ 9. The method of claim 8, wherein the high-toughness and high-efficiency submerged arc flux is prepared by the steps of: The bonding agent is a mixture of lithium water glass and sodium water glass, and the mass percentage of the mixture of lithium water glass and sodium water glass is 1:

1. ​ 10. The method of claim 5, wherein the high-toughness and high-efficiency submerged arc flux is prepared by the steps of: In step (3), the sintering temperature is 850-880℃, and the sintering time is 1-3h. ​

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