Self-cleaning anti-cracking submerged arc flux and preparation method thereof

Abstract

The application belongs to the technical field of welding materials, and specifically provides a self-cleaning anti-cracking submerged arc flux, which comprises, in percentage by mass, 25-30% of magnesium fluoride, 8-15% of calcined alpha aluminum oxide, 15-20% of calcium silicate, 3-12% of rutile, 4-9% of silicon-barium alloy, 2-5% of aluminum-barium alloy, 7-10% of silicon-zirconium alloy, 0.5-1.5% of molybdenum iron, 1.5-2.5% of titanium iron, 0.6-2.0% of boron iron, 0.4-0.7% of vanadium-niobium alloy, 0.6-1.2% of strontium carbonate, 1-2% of cerium fluoride, and the balance of iron powder. The self-cleaning anti-cracking submerged arc flux has high toughness and excellent anti-cracking performance, and can be used in combination with H10Mn2, EH14, H08Mn2E and other welding wires to meet the welding requirements of 50-55Kg grade thick plates Q345, Q420, Q460 and other materials at-60 DEG C in the wind power industry.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of welding materials, and particularly relates to a self-cleaning anti-cracking 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 high attention to and develop, and plays a crucial role in energy and environmental protection. As of the end of 2022, the newly added wind power hoisting capacity was 49.83 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 also increasingly used in the wind power industry. In the welding material matching aspect, the domestic submerged arc welding wire for the wind power industry is mostly H10Mn2 and EH14 conventional carbon steel welding wire, and the flux is mostly SJ101 series fluoroalkali type flux. However, there are still many problems in the production and manufacturing process of thick plates for wind power generation, such as the decrease in crack resistance of thick plate welding due to the enrichment of impurity elements such as S and P, the difficulty in deslagging at the root of the narrow gap of thick plate welding, and the problem of coarse weld structure and impact performance decrease caused by high heat input welding. The present application provides a self-cleaning anti-cracking submerged arc flux for thick plates in the wind power industry. SUMMARY

[0003] The purpose of the present application is to overcome the problems of decrease in crack resistance, difficulty in deslagging at the root of the narrow gap of thick plate welding, and coarse weld structure and impact performance decrease caused by high heat input welding in the existing thick plate welding.

[0004] To this end, the present application provides a self-cleaning anti-cracking submerged arc flux. The submerged arc flux comprises, in mass percentage: 25-30% of magnesium fluoride, 8-15% of calcined alpha aluminum oxide, 15-20% of calcium silicate, 3-12% of rutile, 4-9% of silicon-barium alloy, 2-5% of aluminum-barium alloy, 7-10% of silicon-zirconium alloy, 0.5-1.5% of molybdenum iron, 1.5-2.5% of titanium iron, 0.6-2.0% of boron iron, 0.4-0.7% of vanadium-niobium alloy, 0.6-1.2% of strontium carbonate, 1-2% of cerium fluoride, and the balance being iron powder.

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

[0006] Specifically, the particle size of the above-mentioned submerged arc flux is 12-60 mesh.

[0007] Specifically, the alkalinity of the above-mentioned submerged arc flux is 2.2-2.5.

[0008] Specifically, the loose packing ratio of the above-mentioned submerged arc flux is 1.2-1.3 g / cm 3 .

[0009] The application also provides a preparation method of the self-cleaning anti-cracking submerged arc flux, comprising the following steps:

[0010] (1) crushing and sieving each raw material of the submerged arc flux, weighing and preparing materials according to mass percentage;

[0011] (2) mixing and uniformly bonding the iron powder and the calcined alpha aluminum oxide, sieving, sintering, sieving, and preparing for use;

[0012] (3) mixing the remaining raw materials and adding a bonding agent, fully stirring and uniformly mixing, sintering, and mixing the product of step (2) to prepare the submerged arc flux.

[0013] Specifically, in step (2), the iron powder and bauxite are mixed and sieved through an 80-mesh sieve, and 1-5% of the resin is used for bonding according to mass percentage.

[0014] Specifically, in step (2), the sintering temperature is 200-250 DEG C, the sintering time is 2-4 h, and the sintering product is sieved through a 40-mesh sieve.

[0015] Specifically, in step (3), the amount of the bonding agent is 7-15% of the mass of the remaining raw materials; 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 DEG C, and the sintering time is 1-3 h.

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

[0018] The self-cleaning anti-cracking submerged arc flux provided by the application can meet the welding requirements of 50-55 Kg grade thick plates Q345, Q420, Q460 and other materials at-60 DEG C when used with H10Mn2, EH14, H08Mn2E and other welding wires. The tensile strength is above 550 MPa, the yield strength is above 460 MPa, and the yield ratio is less than or equal to 0.86. The welding efficiency is high for double-wire submerged arc welding, the low-temperature impact toughness is stable at 250 DEG C, and the-60 DEG C impact toughness is above 100 J. In addition to the high toughness, the welding wire also has excellent crack resistance. When double-wire welding, the CTOD value of the weld center at-25 DEG C is not less than 0.50 mm. The S content in the weld metal is less than or equal to 0.01%, the P content is less than or equal to 0.015%, and the welding wire has a metallurgical cleaning effect. The diffusible hydrogen content in the deposited metal is as low as less than or equal to 3 ml / 100 g, which meets the super-low hydrogen requirement, and the radiographic inspection meets the 1st level requirement in GB / T37910.1. 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 self-cleaning anti-cracking submerged arc welding flux, the submerged arc welding flux comprises, in mass percentage: 25-30% of magnesium fluoride, 8-15% of calcined alpha alumina, 15-20% of calcium silicate, 3-12% of rutile, 4-9% of silicon-barium alloy, 2-5% of aluminum-barium alloy, 7-10% of silicon-zirconium alloy, 0.5-1.5% of molybdenum iron, 1.5-2.5% of titanium iron, 0.6-2.0% of boron iron, 0.4-0.7% of vanadium-niobium alloy, 0.6-1.2% of strontium carbonate, 1-2% of cerium fluoride, and the balance is iron powder. H is removed by adding MgF2 metallurgy; the stability of acicular ferrite in the weld under the condition of large heat input is improved by controlling the suitable Nb, Zr, Ca, Mg, N in the flux to improve the distribution of oxide morphology; the grains are refined by adding Sr, Ce, Ti, B trace elements and part of rare earth in the flux, and the crack propagation is prevented by dispersion strengthening, so that the anti-cracking performance is improved. The alkalinity of the submerged arc welding flux is 2.2-2.5, by adding silicon-barium alloy and aluminum-barium alloy in the flux, and increasing the alkalinity of the flux to 2.2-2.5, the carbon content in the weld is reduced, so that the metallurgical automatic dephosphorization of the welding pool is realized. The S in the submerged arc welding flux is ≤0.020%, and the P is ≤0.025%. The particle size of the submerged arc welding flux is 12-60 mesh, and the mass percentage of 12-18 mesh, 18-20 mesh, 20-40 mesh and 40-60 mesh is 45%, 40%, 10% and 5% respectively. The loose packing ratio of the submerged arc welding flux is 1.2-1.3g / cm 3 The weld forming is improved by controlling the particle size and loose packing ratio, the arc distribution form is improved by adding Sr and cerium fluoride, the weld surface smoothness is improved, the mechanical occlusion of the welding slag is reduced, and the narrow gap root deslagging property is improved.

[0021] The present application also provides a preparation method of the above-mentioned self-cleaning anti-cracking submerged arc welding flux, comprising the following steps:

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

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

[0024] (3) the remaining raw materials are mixed, 7-15% of a binder is added in terms of mass percentage, and after being fully stirred and uniformly mixed, the product is mixed with the product of step (2) after being sintered at a high temperature of 850-880°C for 1-3h to obtain the submerged arc flux. The binder 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. Lithium water glass is used to reduce the moisture absorption of the flux and to reduce the content of diffusible hydrogen in the weld;

[0025] The effect of the self-cleaning anti-cracking submerged arc flux is studied through specific examples.

[0026] Example 1:

[0027] The example provides a self-cleaning anti-cracking submerged arc flux, which comprises, in terms of mass percentage:

[0028] 26% of magnesium fluoride, 9% of calcined alpha aluminum oxide, 20% of calcium silicate, 4% of 98 rutile, 5% of silicon-barium alloy, 5% of aluminum-barium alloy, 8% of silicon-zirconium alloy, 0.6% of molybdenum iron, 1.5% of titanium iron, 0.6% of boron iron, 0.7% of vanadium-niobium alloy, 0.6% of strontium carbonate, 1% of cerium fluoride, and the rest is 270 iron powder.

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

[0030] The alkalinity of the submerged arc flux is 2.23, the particle size is 12-60 mesh, the mass percentage of 12-18 mesh, 18-20 mesh, 20-40 mesh and 40-60 mesh is 45%, 40%, 10% and 5%, and the loose packing ratio is 1.22g / cm 3 .

[0031] The example provides a high-toughness and high-efficiency submerged arc flux, which is prepared through the following steps:

[0032] (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;

[0033] (2) the iron powder and the calcined alpha aluminum oxide are mixed uniformly, sieved through an 80-mesh sieve, and then 4% of a resin binder is added in terms of mass percentage, and after being sintered at a low temperature of 200-250°C for 3h, the product is sieved through a 40-mesh sieve and is ready for use;

[0034] (3) the remaining raw materials are mixed, 8% of a binder is added in terms of mass percentage, and after being fully stirred and uniformly mixed, the product is mixed with the product of step (2) after being sintered at a high temperature of 850-880°C for 2h to obtain the submerged arc flux.

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

[0036] The submerged arc flux provided in the embodiment is subjected to deposited metal experiment, the experiment adopts EH14 double-wire welding, the obtained mechanical property results are shown in Table 1, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The mechanical property and CTOD (-25 DEG C) experimental results of the 100 mm plate thickness butt joint are shown in Table 2.

[0037] Embodiment 2:

[0038] The embodiment provides a self-cleaning anti-cracking submerged arc flux, the submerged arc flux comprises, in mass percentage:

[0039] Magnesium fluoride 27%; calcined alpha alumina 14%; calcium silicate 17%; 98 rutile 6%; silicon-barium alloy 6%; aluminum-barium alloy 2%; silicon-zirconium alloy 9%; molybdenum iron 0.8%; titanium iron 2.0%; boron iron 0.8%; vanadium-niobium alloy 0.4%; strontium carbonate 0.8%, cerium fluoride 1.6%, and the rest is 270 iron powder.

[0040] S in the flux: 0.015%; P: 0.017%.

[0041] The alkalinity of the submerged arc flux is 2.28; 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%; and the loose packing ratio is 1.25 g / cm 3 .

[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 subjected to rough crushing, fine crushing, powdering and other processes to process powder of different standard particle sizes, and after sieving, the powder is weighed and matched according to the formula;

[0044] (2) the iron powder and the calcined alpha alumina are uniformly mixed, sieved through an 80-mesh sieve, and after low-temperature sintering at 200-250 DEG C for 2.5 h with 3.5% resin as a binder, the product is sieved through a 40-mesh sieve and is ready for use;

[0045] (3) the remaining raw materials are mixed, 10% binder is added according to the mass percentage, and after fully stirring and uniformly mixing, the product is mixed with the product of step (2) after sintering at 850-880 DEG C for 1.5 h to obtain the submerged arc flux.

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

[0047] The submerged arc flux provided in the embodiment is subjected to deposited metal experiment, the experiment adopts EH14 double-wire welding, the obtained mechanical property results are shown in Table 1, the requirements of ultra-low hydrogen are reached, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The experimental results of mechanical properties and CTOD (-25 DEG C) of 100 mm plate thickness butt joint are shown in Table 2.

[0048] Embodiment 3:

[0049] The embodiment provides a self-cleaning anti-cracking submerged arc flux, the submerged arc flux comprises, in mass percentage:

[0050] Magnesium fluoride 28%; calcined alpha alumina 12%; calcium silicate 15%; 98 rutile 8%; silicon-barium alloy 7%; aluminum-barium alloy 4%; silicon-zirconium alloy 7%; molybdenum iron 1.0%; titanium iron 1.7%; boron iron 1.0%; vanadium-niobium alloy 0.5%; strontium carbonate 1.0%, cerium fluoride 1.4%, and the rest is 270 iron powder.

[0051] S in the flux: 0.015%; P: 0.015%.

[0052] The alkalinity of the submerged arc flux is 2.32; the particle size 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%; the loose packing ratio is 1.26 g / cm 3 .

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

[0054] (1) The raw materials of the submerged arc flux are subjected to rough crushing, fine crushing, powdering and other processes to process powder of different standard particle sizes, and after sieving, the powder is weighed and matched according to the formula;

[0055] (2) The iron powder and the calcined alpha alumina are uniformly mixed, sieved through an 80-mesh sieve, and after low-temperature sintering at 200-250 DEG C for 3h with 2% resin binder, the product is sieved through a 40-mesh sieve and is ready for use;

[0056] (3) The remaining raw materials are mixed, 10% binder is added according to the mass percentage, and after fully stirring and uniformly mixing, the product is mixed with the product of step (2) after sintering at 850-880 DEG C for 3h to obtain the submerged arc flux.

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

[0058] The submerged arc flux provided in the embodiment is subjected to deposited metal experiment, the experiment adopts EH14 double-wire welding, the obtained mechanical property results are shown in Table 1, the requirements of ultra-low hydrogen are reached, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The experimental results of mechanical properties and CTOD (-25 DEG C) of 100 mm plate thickness butt joint are shown in Table 2.

[0059] Embodiment 4:

[0060] The embodiment provides a self-cleaning anti-cracking submerged arc flux, the submerged arc flux comprises, in mass percentage:

[0061] Magnesium fluoride 29%; calcined alpha alumina 10%; calcium silicate 16%; 98 rutile 10%; silicon-barium alloy 8%; aluminum-barium alloy 3%; silicon-zirconium alloy 10%; molybdenum iron 1.2%; titanium iron 2.4%; boron iron 2.0%; vanadium-niobium alloy 0.7%; strontium carbonate 0.7%, cerium fluoride 1.5%, and the rest is 270 iron powder.

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

[0063] The alkalinity of the submerged arc flux is 2.38; the particle size 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%; the loose packing ratio is 1.30 g / cm 3 .

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

[0065] (1) the raw materials of the submerged arc flux are subjected to rough crushing, fine crushing, powdering and other processes, and are processed into powder of different standard particle sizes, and after sieving, the powder is weighed and matched according to the formula;

[0066] (2) the iron powder and the calcined alpha alumina are uniformly mixed, and after being sieved through an 80-mesh sieve, 4.5% of resin is used for bonding, and after low-temperature sintering at 200-250 DEG C for 3.5 h, the product is sieved through a 40-mesh sieve and is ready for use;

[0067] (3) the remaining raw materials are mixed, 14% of a bonding agent is added according to mass percentage, and after being fully stirred and uniformly mixed, the product is mixed with the product of step (2) after sintering at 850-880 DEG C for 3 h, so as to obtain the submerged arc flux.

[0068] The bonding agent is a mixture of lithium water glass and sodium water glass in a mass percentage of 1:1.

[0069] The submerged arc flux provided in the embodiment is subjected to deposited metal experiment, the experiment adopts EH14 double-wire welding, the obtained mechanical property results are shown in Table 1, the requirements of ultra-low hydrogen are reached, and the radiographic inspection meets the 1st level requirement in GB / T 37910.1. The experimental results of mechanical properties and CTOD (-25 DEG C) of 100 mm plate thickness butt joint are shown in Table 2.

[0070] Embodiment 5:

[0071] The embodiment provides a self-cleaning anti-cracking submerged arc flux, the submerged arc flux comprises, in mass percentage:

[0072] 25% of magnesium fluoride, 13% of calcined alpha alumina, 17% of calcium silicate, 12% of 98 rutile, 7% of silicon-barium alloy, 4% of aluminum-barium alloy, 8% of silicon-zirconium alloy, 1.4% of molybdenum iron, 1.8% of titanium iron, 1.5% of boron iron, 0.5% of vanadium-niobium alloy, 0.9% of strontium carbonate, 1.8% of cerium fluoride, and the rest is 270 iron powder.

[0073] S: 0.014% in the flux; P: 0.025%.

[0074] The alkalinity of the submerged arc flux is 2.43; the particle size 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; the loose packing ratio is 1.28 g / cm 3 .

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

[0076] (1) the raw materials of the submerged arc flux are subjected to rough crushing, fine crushing, powdering and other processes to process powder of different standard particle sizes, and after sieving, the powder is weighed and matched according to the formula;

[0077] (2) the iron powder and the calcined alpha alumina are uniformly mixed, and after being sieved through an 80-mesh sieve, 2% of resin is used for bonding, and after low-temperature sintering at 200-250 DEG C for 2.5 h, the product is sieved through a 40-mesh sieve and is ready for use;

[0078] (3) the remaining raw materials are mixed, 11% of a bonding agent is added according to the mass percentage, and after being fully stirred and uniformly mixed, the product is sintered at 850-880 DEG C for 2.5 h, and then the product is mixed with the product of step (2) to obtain the submerged arc flux.

[0079] The bonding agent is a mixture of lithium water glass and sodium water glass in a mass percentage of 1:1.

[0080] The submerged arc flux provided by the embodiment is subjected to a deposited metal experiment, the experiment adopts EH14 double-wire welding, the obtained mechanical property results are shown in Table 1, the super-low hydrogen requirement is reached, and the radiographic inspection satisfies the 1st level requirement in GB / T 37910.1. The mechanical property and CTOD (-25 DEG C) experimental results of 100 mm thick butt joint are shown in Table 2.

[0081] Table 1 Mechanical property of deposited metal

[0082]

[0083] Table 2 Mechanical property and CTOD (-25 DEG C) experimental results of 100 mm thick butt joint

[0084]

[0085]

[0086] As shown in Table 1 and Table 2, the self-cleaning anti-cracking submerged arc flux provided by the embodiment has a tensile strength of 550 MPa or more, a yield strength of 460 MPa or more, a yield strength ratio of 0.86 or less, an elongation of more than 27%, double-wire submerged arc welding of -60 DEG C of more than 120 J, and a CTOD value of the weld center of 100 mm thick steel plate double-wire welding at -25 DEG C of not less than 0.50 mm. The S content in the weld metal is 0.01% or less, the P content is 0.015% or less, and the submerged arc flux has a metallurgical cleaning effect. The diffusion hydrogen content in the deposited metal is as low as 3 ml / 100 g or less, the super-low hydrogen requirement is reached, and the radiographic inspection satisfies the 1st level requirement in GB / T 37910.1.

[0087] The above examples are only illustrative of the present application and do not constitute a limitation on the protection scope of the present application, and any design identical or similar to the present application falls within the protection scope of the present application.

Claims

1. A self-cleaning, crack-resistant submerged arc welding flux, characterized in that, By weight percentage, the submerged arc welding flux comprises: 25-30% magnesium fluoride, 8-15% calcined α-alumina, 15-20% calcium silicate, 3-12% rutile, 4-9% silicon barium alloy, 2-5% aluminum barium alloy, 7-10% silicon zirconium alloy, 0.5-1.5% ferromolybdenum, 1.5-2.5% ferrotitanium, 0.6-2.0% ferroborone, 0.4-0.7% vanadium niobium alloy, 0.6-1.2% strontium carbonate, 1-2% cerium fluoride, with the balance being iron powder; the self-cleaning crack-resistant submerged arc welding flux is used in conjunction with H10Mn2, EH14, and H08Mn2E welding wires.

2. The self-cleaning, crack-resistant submerged arc welding flux as described in claim 1, characterized in that: The submerged arc welding flux contains S≤0.020% and P≤0.025%.

3. The self-cleaning, crack-resistant submerged arc welding flux as described in claim 1, characterized in that: The particle size of the submerged arc welding flux is 12-60 mesh.

4. The self-cleaning, crack-resistant submerged arc welding flux as described in claim 1, characterized in that: The basicity of the submerged arc welding flux is 2.2-2.

5.

5. The self-cleaning, crack-resistant submerged arc welding flux as described in claim 1, characterized in that: The loose charge ratio of the submerged arc welding flux is 1.2-1.3 g / cm³. 3 .

6. The method for preparing the self-cleaning, crack-resistant submerged arc welding flux as described in any one of claims 1-5, characterized in that, Includes the following steps: (1) After crushing and sieving the raw materials of submerged arc welding flux, weigh them according to the mass percentage and prepare the materials; (2) Mix iron powder with calcined α-alumina evenly, sieve, bind with resin, sinter, sieve, and set aside; (3) Mix the remaining raw materials and add binder, stir thoroughly and evenly, sinter and mix with the product of step (2) to obtain the submerged arc welding flux.

7. The preparation method of the self-cleaning crack-resistant submerged arc welding flux as described in claim 6, characterized in that: In step (2), the iron powder and bauxite are mixed and passed through an 80-mesh sieve, and 1-5% resin is used for bonding by mass percentage.

8. The preparation method of the self-cleaning crack-resistant submerged arc welding flux as described in claim 6, characterized in that: In step (2), the sintering temperature is 200-250℃, the sintering time is 2-4h, and the sintered material is passed through a 40-mesh sieve.

9. The preparation method of the self-cleaning crack-resistant submerged arc welding flux as described in claim 6, characterized in that: In step (3), the amount of binder used is 7-15% of the mass of the remaining raw materials; the binder 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 preparation method of the self-cleaning crack-resistant submerged arc welding flux as described in claim 6, characterized in that: The sintering temperature in step (3) is 850-880℃ and the sintering time is 1-3h.

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