Wire electrode submerged arc sintering flux for high temperature nickel-based alloy and preparation method thereof

Abstract

The present invention relates to a wire-submerged arc sintering flux for high-temperature nickel-based alloys and a preparation method thereof. Specifically, the wire-submerged arc welding sintering flux for high-temperature nickel-based alloys is prepared by mixing the following fine powders: fluorite, sillimanite, white corundum, magnesia, mica, cryolite, and clay. The flux is prepared according to the following process: seven kinds of fine powders of fluorite, sillimanite, white corundum, magnesia, mica, cryolite, and clay are mixed and dry-mixed in a formula ratio, and then potassium sodium silicate is added and stirred and mixed to obtain a mixture; the mixture is first dried at a low temperature of 180 to 230°C, and then sintered at a high temperature of 700 to 900°C and sieved to obtain a granular wire-submerged arc welding sintering flux for high-temperature nickel-based alloys. The flux obtained by the present invention exhibits excellent effects as described in the specification.

Description

Technical Field

[0001] The present invention belongs to the field of welding materials, and relates to a sintering flux, and specifically to a wire-electrode submerged arc sintering flux for high-temperature nickel-based alloys. The sintering flux is used in combination with a nickel-based alloy welding wire, and can be used for welding nickel-based alloys, and exhibits excellent effects as described herein. The present invention also relates to a method for preparing such a wire-electrode submerged arc sintering flux for high-temperature nickel-based alloys. Background Art

[0002] In recent years, with the development of modern industry, the requirements for material performance are getting higher and higher, and the service environment of equipment is becoming more and more harsh. In order to meet various harsh use environments, high-pressure and high-temperature resistant nickel-based corrosion-resistant alloys have been widely recognized by various industries due to their excellent performance. Widely used in land-based or ship-based gas turbines, high-temperature combustion chambers of various aerospace and aviation engines, flue gas desulfurization equipment in thermal power plants, military weapons and equipment, as well as traditional industrial equipment such as petroleum refining and various chemical industries, nickel-based alloys also occupy an important position in the fields of clean energy such as nuclear power and photovoltaics. The demand for high-pressure and high-temperature resistant nickel-based corrosion-resistant alloys is growing. Therefore, the development of efficient high-temperature nickel-based alloy wire electrode submerged arc welding materials will have significant economic benefits and broad application prospects.

[0003] When welding nickel-based alloys, the main components of the weld are iron and nickel, which are infinitely soluble in each other and do not form intermetallic compounds. Under normal circumstances, a diffusion layer will not form in the fusion zone of the weld joint. The main problem of welding is that pores and thermal cracks are easily generated in the weld. For solution-strengthened nickel-based alloys, rapid cooling from the solution annealing temperature is required to avoid the formation of carbides or embrittled fine particles during the cooling process.

[0004] Solution strengthening treatment can reduce alloy element segregation by increasing the solution temperature, prolonging the solution time, and increasing the solution steps. However, as the solution temperature increases, the room temperature tensile strength and yield strength of the alloy gradually decrease, while the elongation gradually increases. Therefore, it is necessary to ensure the mechanical properties of the weld metal after rapid cooling at the solution annealing temperature.

[0005] Based on the above background, it is still an urgent expectation of technical personnel in this field to develop a wire electrode submerged arc sintering flux for high-temperature nickel-based alloys, which, after being welded with nickel-based alloy welding wire, has a weld metal with good resistance to intergranular corrosion and high-temperature tensile strength, and / or, the weld metal and its weld joint still have excellent high-temperature tensile properties after solution treatment and meet the use conditions of corresponding working conditions. Summary of the invention

[0006] The purpose of the present invention is to provide a wire-electrode submerged arc welding sintered flux for high-temperature nickel-based alloys, and it is expected that after being welded with nickel-based alloy welding wire, the obtained weld metal has good intergranular corrosion resistance and / or high-temperature tensile strength, and / or the weld metal and its weld joint still have excellent high-temperature tensile properties after solid solution treatment, meeting the use conditions of corresponding working conditions. The inventor unexpectedly found that the designed aluminum-fluorine-alkali type sintered flux with the main chemical composition of CaF2-Al2O3 can obtain one or more of the above-mentioned excellent technical properties when welded with nickel alloy welding wire, and the present invention is completed based on such findings.

[0007] To this end, the first aspect of the present invention provides a wire electrode submerged arc welding sintering flux for high-temperature nickel-based alloys, characterized in that it is made by mixing fine powders in the following proportions: 30-40 parts by weight of fluorite, 15-30 parts by weight of sillimanite, 20-30 parts by weight of white corundum, 3-10 parts by weight of magnesite, 3-10 parts by weight of mica, 3-10 parts by weight of cryolite, and 3-10 parts by weight of clay.

[0008] The sintered flux for wire electrode submerged arc welding of high temperature nickel-based alloy according to the first aspect of the present invention is characterized in that it is made by mixing fine powders in the following proportions: 30-38 parts by weight of fluorite, 15-25 parts by weight of sillimanite, 20-25 parts by weight of white corundum, 6-10 parts by weight of magnesia, 5-7 parts by weight of mica, 5-7 parts by weight of cryolite, and 5-10 parts by weight of clay.

[0009] The sintered flux for wire submerged arc welding of high-temperature nickel-based alloys according to the first aspect of the present invention is characterized in that it is made by mixing fine powders in the following proportions: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 8 parts by weight of magnesia, 5 parts by weight of mica, 6 parts by weight of cryolite, and 8 parts by weight of clay. For example, it has the ingredient proportions described in any embodiment.

[0010] The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to the first aspect of the present invention is characterized in that it is a granular material prepared from the fine powder and the binder potassium sodium silicate in the said proportion.

[0011] The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to the first aspect of the present invention is characterized in that it is a granular material prepared from fine powder and a binder potassium sodium silicate in the said proportion, and the weight of the potassium sodium silicate used is 22-25% of the total weight of the fine powder.

[0012] The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to the first aspect of the present invention is characterized in that the potassium-sodium ratio of the binder potassium sodium silicate is 1.5:1.

[0013] The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to the first aspect of the present invention is characterized in that the modulus of the binder potassium sodium silicate is 2.7.

[0014] The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to the first aspect of the present invention is characterized in that the binder potassium sodium silicate has a Baume degree of 43 at a temperature of 20°C.

[0015] The wire electrode submerged arc welding sintered flux for high temperature nickel-based alloy according to the first aspect of the present invention is characterized in that the binder potassium sodium silicate has a potassium-sodium ratio of 1.5:1, a modulus of 2.7, and a Baume degree of 43 at 20°C.

[0016] According to the first aspect of the present invention, the wire electrode submerged arc welding sintered flux for high temperature nickel-based alloy is characterized in that it is prepared according to the following process: seven kinds of fine powders of fluorite, sillimanite, white corundum, magnesia, mica, cryolite and clay are mixed and dry-mixed in a formula ratio (for example, 2 to 10 minutes, for example, 3 minutes to 5 minutes), and then potassium sodium silicate is added and continued to be stirred and mixed (for example, 2 to 10 minutes, for example, 4 minutes to 6 minutes) to obtain a mixture; the mixture is first dried at a low temperature (for example, 180 to 230° C., for example, 200° C.) (for example, 35-60 minutes, for example, 45 minutes, for example, to remove 99% of the moisture), and then sintered at a high temperature (for example, 700 to 900° C., for example, 800° C.) (for example, 50-70 minutes, for example, 60 minutes), and sieved to obtain a granular wire electrode submerged arc welding sintered flux for high temperature nickel-based alloy (which can be used in conjunction with the corresponding welding wire).

[0017] The wire electrode submerged arc welding sintered flux for high temperature nickel-based alloy according to the first aspect of the present invention has a particle size of 10-60 meshes, for example, a particle size of 10-50 meshes.

[0018] According to the first aspect of the present invention, the wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy has a formula of any weight proportion described in any one of items N1 to N5 below:

[0019] N1: 30 parts by weight of fluorite, 25 parts by weight of sillimanite, 20 parts by weight of white corundum, 10 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 5 parts by weight of clay;

[0020] N2: 35 parts by weight of fluorite, 15 parts by weight of sillimanite, 25 parts by weight of white corundum, 8 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 10 parts by weight of clay;

[0021] N3: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 8 parts by weight of magnesia, 5 parts by weight of mica, 6 parts by weight of cryolite, and 8 parts by weight of clay;

[0022] N4: 35 parts by weight of fluorite, 20 parts by weight of sillimanite, 20 parts by weight of white corundum, 6 parts by weight of magnesite, 5 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay;

[0023] N5: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 6 parts by weight of magnesite, 7 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay.

[0024] According to the first aspect of the present invention, the wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy has a formula of any weight proportion described in any one of items N1 to N5 below:

[0025] N1: 30 parts by weight of fluorite, 25 parts by weight of sillimanite, 20 parts by weight of white corundum, 10 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 5 parts by weight of clay;

[0026] N2: 35 parts by weight of fluorite, 15 parts by weight of sillimanite, 25 parts by weight of white corundum, 8 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 10 parts by weight of clay;

[0027] N3: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 8 parts by weight of magnesia, 5 parts by weight of mica, 6 parts by weight of cryolite, and 8 parts by weight of clay;

[0028] N4: 35 parts by weight of fluorite, 20 parts by weight of sillimanite, 20 parts by weight of white corundum, 6 parts by weight of magnesite, 5 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay;

[0029] N5: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 6 parts by weight of magnesite, 7 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay,

[0030] And the preparation method is as follows: the raw materials for the required sintered flux are weighed according to the formula, and after the total weight is double-checked, the raw materials are put into a dry mixer for dry mixing for 2 to 10 minutes (for example, 4 minutes), and after dry mixing is uniform, the raw materials are poured into a wet mixer, potassium sodium silicate (24% of the total weight of the dry powder) is added for wet mixing for 2 to 10 minutes (for example, 5 minutes), and after wet mixing is uniform, the wet powder is sent to a granulation disk through a conveyor belt for granulation, and after granulation is completed, the raw materials are sent to a low-temperature furnace through a conveyor belt, and dried for 35 to 60 minutes (for example, 45 minutes) at 180-230° C. (for example, 200° C.) environment, and then lifted and sieved by an elevator, and the semi-finished flux within the standard particle size range after screening is transported to a high-temperature kiln for sintering, and sintered at a high temperature of 700-900° C. (for example, 800° C.) for 50-70 minutes (for example, 60 minutes), and after leaving the kiln, it is cooled, lifted, sieved (10 to 50 meshes), and packaged to make a finished flux.

[0031] Furthermore, the second aspect of the present invention provides a method for preparing a sintered wire electrode submerged arc welding flux for high-temperature nickel-based alloys, characterized in that it comprises the following steps: mixing seven kinds of fine powders of fluorite, sillimanite, white corundum, magnesia, mica, cryolite, and clay in a formula ratio and dry mixing (for example, 2 to 10 minutes, for example, 3 minutes to 5 minutes), and then adding potassium sodium silicate and continuing to stir and mix (for example, 2 to 10 minutes, for example, 4 minutes to 6 minutes) to obtain a mixture; the mixture is first dried at a low temperature (for example, 180 to 230°C, for example, 200°C) (for example, 35-60 minutes, for example, 45 minutes, for example, to remove 99% of the moisture), and then sintered at a high temperature (for example, 700 to 900°C, for example, 800°C) (for example, 50-70 minutes, for example, 60 minutes), and sieved to obtain a granular sintered wire electrode submerged arc welding flux for high-temperature nickel-based alloys (which can be used in conjunction with the corresponding welding wire).

[0032] The method according to the second aspect of the present invention is characterized in that the proportions of the fine powders are: 30-40 parts by weight of fluorite, 15-30 parts by weight of sillimanite, 20-30 parts by weight of white corundum, 3-10 parts by weight of magnesite, 3-10 parts by weight of mica, 3-10 parts by weight of cryolite, and 3-10 parts by weight of clay.

[0033] The method according to the second aspect of the present invention is characterized in that the weight of potassium sodium silicate used is 22-25% of the total weight of the fine powder.

[0034] The method according to the second aspect of the present invention is characterized in that the potassium-sodium ratio of the binder potassium sodium silicate is 1.5:1.

[0035] The method according to the second aspect of the present invention is characterized in that the modulus of the binder potassium sodium silicate is 2.7.

[0036] The method according to the second aspect of the present invention is characterized in that the binder potassium sodium silicate has a Baume degree of 43 at a temperature of 20°C.

[0037] The method according to the second aspect of the present invention is characterized in that the binder potassium sodium silicate has a potassium-sodium ratio of 1.5:1, a modulus of 2.7, and a Baume degree of 43 at 20°C.

[0038] The method according to the second aspect of the present invention is characterized in that the granular high-temperature nickel-based alloy wire electrode submerged arc welding sintering flux has a particle size of 10-60 meshes, for example, a particle size of 10 to 50 meshes.

[0039] The method according to the second aspect of the present invention is characterized in that the wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy has a formula of the following weight proportions as described in any one of items N1 to N5:

[0040] N1: 30 parts by weight of fluorite, 25 parts by weight of sillimanite, 20 parts by weight of white corundum, 10 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 5 parts by weight of clay;

[0041] N2: 35 parts by weight of fluorite, 15 parts by weight of sillimanite, 25 parts by weight of white corundum, 8 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 10 parts by weight of clay;

[0042] N3: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 8 parts by weight of magnesia, 5 parts by weight of mica, 6 parts by weight of cryolite, and 8 parts by weight of clay;

[0043] N4: 35 parts by weight of fluorite, 20 parts by weight of sillimanite, 20 parts by weight of white corundum, 6 parts by weight of magnesite, 5 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay;

[0044] N5: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 6 parts by weight of magnesite, 7 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay.

[0045] The method according to the second aspect of the present invention is characterized in that the wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy has a formula of the following weight proportions as described in any one of items N1 to N5:

[0046] N1: 30 parts by weight of fluorite, 25 parts by weight of sillimanite, 20 parts by weight of white corundum, 10 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 5 parts by weight of clay;

[0047] N2: 35 parts by weight of fluorite, 15 parts by weight of sillimanite, 25 parts by weight of white corundum, 8 parts by weight of magnesite, 5 parts by weight of mica, 5 parts by weight of cryolite, and 10 parts by weight of clay;

[0048] N3: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 8 parts by weight of magnesia, 5 parts by weight of mica, 6 parts by weight of cryolite, and 8 parts by weight of clay;

[0049] N4: 35 parts by weight of fluorite, 20 parts by weight of sillimanite, 20 parts by weight of white corundum, 6 parts by weight of magnesite, 5 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay;

[0050] N5: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 6 parts by weight of magnesite, 7 parts by weight of mica, 7 parts by weight of cryolite, and 8 parts by weight of clay,

[0051] In addition, the method comprises the following steps: weighing the raw materials for the required sintering flux according to the formula, rechecking the total weight and putting the raw materials into a dry mixer for dry mixing for 2-10 minutes (for example, 4 minutes), pouring the raw materials into a wet mixer after dry mixing, adding potassium sodium silicate (24% of the total weight of the dry powder) for wet mixing for 2-10 minutes (for example, 5 minutes), sending the wet powder into a granulation disk through a conveyor belt for granulation after wet mixing, sending the wet powder into a low-temperature furnace through a conveyor belt after granulation, drying for 35-60 minutes (for example, 45 minutes) under an environment of 180-230°C (for example, 200°C), then lifting and screening by a hoist, conveying the semi-finished flux within the standard particle size range after screening to a high-temperature kiln for sintering, sintering at a high temperature of 700-900°C (for example, 800°C) for 50-70 minutes (for example, 60 minutes), cooling, lifting, screening (10-50 meshes), and packaging after leaving the kiln to make a finished flux.

[0052] Any embodiment of any aspect of the present invention can be combined with other embodiments, as long as they do not conflict. In addition, in any embodiment of any aspect of the present invention, any technical feature can be applied to the technical features in other embodiments, as long as they do not conflict. The present invention is further described below.

[0053] All documents cited in the present invention are incorporated herein by reference in their entirety, and if the meanings expressed in these documents are inconsistent with the present invention, the description of the present invention shall prevail. In addition, the various terms and phrases used in the present invention have the general meanings known to those skilled in the art. Even so, the present invention still hopes to provide a more detailed description and explanation of these terms and phrases. If the terms and phrases mentioned are inconsistent with the known meanings, the meanings expressed in the present invention shall prevail.

[0054] The various terms and phrases used in the present invention have general meanings known to those skilled in the art. Even so, the present invention still hopes to provide a more detailed description and explanation of these terms and phrases herein. If the mentioned terms and phrases are inconsistent with the known meanings, the meanings expressed in the present invention shall prevail.

[0055] In the present invention, the term "parts by weight" indicates the relative amount of each component in the welding wire coating of the present invention, and the "parts by weight" may be an absolute weight number (e.g., mg, g, or kg, etc.) or a weight percentage (e.g., weight % or wt%). Of course, when expressed in weight percentage (e.g., weight % or wt%), a preferred embodiment is that the sum of each component is 100%.

[0056] In the present invention, various ingredients used are well known in the art, such as fluorite, sillimanite, white corundum, magnesia, mica, cryolite, clay, potassium sodium water glass and the like, all of which have well-known meanings in the art, are raw materials commonly used by those skilled in the art in the preparation of welding materials, and can be directly purchased from the market with the above-mentioned product names.

[0057] As is known to all, the main component of fluorite used in the present invention is CaF2, the main component of magnesite is MgO, the main component of sillimanite is SiO2 and Al2O3, the main component of white corundum is Al2O3, the main component of mica is SiO2 and Al2O3, the main component of cryolite is Na3AlF6, and the main component of clay is SiO2 and Fe2O3.

[0058] The flux obtained by the present invention has excellent technical effects as described in the context of the present invention, such as but not limited to the following advantages:

[0059] The sintering flux of the invention has excellent slag removal performance.

[0060] The present invention adjusts the melting point, density, viscosity, tension, etc. of the slag by accurately controlling the added amounts of the halogen compound and the alkaline oxide, thereby ensuring the quality of the weld.

[0061] The present invention sintered the flux, generally at a drying temperature of 180-230°C, to remove 99% of the moisture, and then sintered at a high temperature of 700-900°C to ensure that the obtained flux has high strength and low hygroscopicity, thereby ensuring the diffused hydrogen content and oxygen content of the cladding layer metal.

[0062] The invention adds mica to the flux. The mica is elastic, which is beneficial to the production of the flux and can also increase the air permeability of the flux, so that the flux sintering efficiency is higher.

[0063] The invention reasonably adjusts the proportion of each component of the flux, designs a reasonable flux slag system, and well adjusts the viscosity, surface tension and fluidity of the slag. When the flux is used for welding, the welding process is stable and the slag removal performance is excellent. DETAILED DESCRIPTION

[0064] The present invention can be further described by the following examples, however, the scope of the present invention is not limited to the following examples. It will be appreciated by those skilled in the art that various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. The present invention provides general and / or specific descriptions of the materials and test methods used in the test. Although many materials and operating methods used to achieve the purpose of the present invention are well known in the art, the present invention is still described in as much detail as possible at this point.

[0065] Example 1: Preparation of Wire Submerged Arc Welding Sintering Flux for High-Temperature Nickel-Based Alloy

[0066] In this embodiment 1, five kinds of fluxes are prepared, numbered N1-N5. The weight percentage of each component of the five sintered fluxes is shown in Table 1:

[0067] Table 1: Flux components and weight ratio of each component (100g)

[0068]

[0069]

[0070] The flux preparation method is as follows:

[0071] The raw materials for the required sintering flux are weighed according to the formula, and after the total weight is double-checked, the powder is put into a dry mixer for dry mixing for 2-10 minutes (4 minutes in this embodiment), and after dry mixing is uniform, it is poured into a wet mixer, and potassium sodium silicate (24% of the total weight of the dry powder) is added for wet mixing for 2-10 minutes (5 minutes in this embodiment). After wet mixing is uniform, the wet powder is sent to a granulation disk through a conveyor belt for granulation. After granulation is completed, it is sent to a low-temperature furnace through a conveyor belt, and dried at 180-230° C. (200° C. in this embodiment) for 35-60 minutes (45 minutes in this embodiment, removing 99% of the moisture), and then lifted and sieved by an elevator. The semi-finished flux within the standard particle size range after sieving is transported to a high-temperature kiln for sintering, and sintered at a high temperature of 700-900° C. (800° C. in this embodiment) for 50-70 minutes (60 minutes in this embodiment). After leaving the kiln, it is cooled, lifted, sieved (10-50 meshes), and packaged to make a finished flux.

[0072] The potassium sodium silicate used in this embodiment has a potassium to sodium ratio of 1.5:1, a modulus of 2.7, and a Baume degree of 43 at 20°C.

[0073] The five prepared fluxes were respectively combined with ERNiCrMo-2 welding wire for welding tests. The steel plate used in the test was Q235 carbon steel with a thickness of 20 mm and a welding wire diameter of 2.5 mm. The welding process parameters are shown in Table 2.

[0074] Table 2: Welding process parameters

[0075] Current, A Voltage, V Welding speed, m / h Stem elongation, mm 300-350 28-32 18-24 22-35

[0076] The inventors determined the chemical composition of the welding wire and the deposited metal using conventional methods in the art. The results are shown in Table 3.

[0077] Table 3: Chemical composition of welding wire and deposited metal, wt.%

[0078] C Si Mn S P Cr Ni Mo Fe Co W ERNiCrMo-2 welding wire 0.070 0.10 0.23 0.003 0.005 22.18 margin 9.05 18.45 1.05 0.70 N1 deposited metal 0.067 0.36 0.22 0.008 0.010 21.05 50.18 8.78 17.59 0.91 0.50 N2 deposited metal 0.060 0.28 0.17 0.007 0.007 20.15 51.09 8.85 17.76 0.84 0.48 N3 deposited metal 0.041 0.28 0.16 0.007 0.014 21.09 50.54 8.93 17.49 0.87 0.47 N4 deposited metal 0.048 0.23 0.19 0.006 0.013 21.10 50.92 8.73 17.42 0.83 0.42 N5 deposited metal 0.042 0.32 0.22 0.009 0.016 20.79 50.48 8.89 17.56 0.86 0.46

[0079] Welding tests were carried out on the above five fluxes with four scoring levels of excellent (3 points), good (2 points), medium (1 point), and poor (0 points) to evaluate the welding process performance. The results are shown in Table 4.

[0080] Table 4: Flux welding process performance

[0081] Welding stability Weld bead forming Slag removal Comprehensive score N1 excellent good middle 6 N2 good good middle 5 N3 excellent excellent excellent 9 N4 good middle middle 4 N5 good good excellent 7

[0082] The results in Table 4 above show that from the perspective of process performance, N3 flux is significantly superior to fluxes of other formulations.

[0083] In view of the fact that the welding process performance of fluxes N1, N3 and N5 shown in Table 4 is better, the mechanical properties of the deposited metals obtained by welding with the above three fluxes are further investigated according to the conventional deposited metal mechanical property test method in this field. The test results are shown in Table 5.

[0084] Table 5: Test results of mechanical properties of deposited metal

[0085] Flux Heat treatment system Tensile strength / MPa Yield strength / MPa Elongation / % N1 Welded 672 453 37.6 N3 Welded 694 482 48.5 N5 Welded 678 459 38.4 N3 1177℃*95min+water cooling 677 379 53.7 N5 1177℃*95min+water cooling 656 361 45.3 N3 Welded state (600℃ high temperature stretching) 453 292 46.5

[0086] From the results in the above table, it can be seen that although the proportions of the five fluxes are slightly different, the performance of N3 flux is significantly better than the other fluxes.

[0087] The mechanical properties of the welded joints obtained by welding with N3 flux were further investigated, and the test results are shown in Table 6.

[0088] Table 6: Mechanical properties test results of welded joints

[0089]

[0090] The above results show that N3 flux has excellent performance.

[0091] Using the same method as Table 6, the tensile strength (MPa) of N1~N2, N4~N5 measured at 600℃ are 373, 364, 357, 368 respectively, and the yield strength (MPa) are 164, 157, 155, 162 respectively. The tensile strength and yield strength measured at 590℃ also show that N3 flux is better.

[0092] Next, according to the standard ASTM G28 A method, the intergranular corrosion of the deposited metal obtained by welding with N1 to N5 fluxes was further tested. The results showed that the intergranular corrosion (mm / y) of the deposited metal obtained by welding with the five fluxes were 1.71, 1.83, 0.83, 1.96, and 1.65, respectively, indicating that N3 has significantly better corrosion resistance.

[0093] In addition, referring to the formula and preparation method of the N3 flux in Example 1, the only difference is that the potassium sodium silicate used is 22% and 25% of the total weight of the dry powder, and the two fluxes are recorded as N31 and N32 respectively; in addition, referring to the formula and preparation method of the N3 flux in Example 1, the only difference is that magnesia is not added, and the obtained flux is recorded as N33; the three fluxes are measured according to the above method. As a result, the comprehensive scores of the welding process performance of the N31, N32 and N33 fluxes are 9 points, 8 points and 2 points respectively, the elongation of the welded condition is 49.7%, 48.2% and 27.6% respectively, and the elongation of the 1177℃*95min+water cooling condition is The elongation rates of the welded state (600℃ high temperature tensile) were 47.4%, 46.2% and 26.7% respectively. The tensile strength of the welded joints at 1177℃*95min+water cooling (600℃) was 407MPa, 396MPa and 237MPa respectively. The intergranular corrosion test of the deposited metal showed that the intergranular corrosion (mm / y) was 0.78, 0.86 and 2.24 respectively. The test results of the other conditions and parameters of N31 and N32 were basically the same as those of N3 flux, but the test results of the other conditions and parameters of N33 were obviously unacceptable. These results show that the N3 formula can be mixed with 22% to 25% potassium sodium silicate and has excellent effects; it also shows that it is necessary to add magnesia to the formula, otherwise the various properties are unacceptable. The results of Example 1 also show that although there is no regularity or significant difference in the changes in the material ratios of the five fluxes N1 to N5, N3 shows significantly better results among these irregularities.

[0094] The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art based on the present invention are within the protection scope of the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A wire electrode submerged arc welding sintering flux for high temperature nickel-based alloys, It is characterized in that The invention is prepared by mixing fine powders in the following proportions: 35 parts by weight of fluorite, 18 parts by weight of sillimanite, 22 parts by weight of white corundum, 8 parts by weight of magnesia, 5 parts by weight of mica, 6 parts by weight of cryolite and 8 parts by weight of clay.

2. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 1, It is characterized in that The granules are prepared from the fine powder and the binder potassium sodium silicate in the stated proportion.

3. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 1, It is characterized in that The granules are prepared from the fine powder and the binder potassium sodium silicate in the said proportion, and the weight of the potassium sodium silicate used is 22-25% of the total weight of the fine powder.

4. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 2, It is characterized in that The potassium-sodium ratio of the binder potassium sodium silicate is 1.5:

1.

5. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 2, It is characterized in that The modulus of the binder potassium sodium silicate is 2.

7.

6. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 2, It is characterized in that The binder potassium sodium silicate has a Baume degree of 43 at a temperature of 20°C.

7. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 2, It is characterized in that The binder potassium sodium silicate has a potassium-sodium ratio of 1.5:1, a modulus of 2.7, and a Baume degree of 43 at 20°C.

8. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 1, It is characterized in that The invention is prepared according to the following process: seven kinds of fine powders of fluorite, sillimanite, white corundum, magnesia, mica, cryolite and clay are mixed and dry-blended in a formula ratio for 2 to 10 minutes, and then potassium sodium silicate is added and stirred and mixed for 2 to 10 minutes to obtain a mixture; the mixture is first dried at a low temperature of 180 to 230°C for 35 to 60 minutes to remove 99% of the moisture, and then sintered at a high temperature of 700 to 900°C for 50 to 70 minutes and sieved to obtain a granular sintered flux for high-temperature nickel-based alloy wire electrode submerged arc welding.

9. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 1, It is characterized in that The invention is prepared according to the following process: seven kinds of fine powders of fluorite, sillimanite, white corundum, magnesia, mica, cryolite and clay are mixed in a formula ratio and dry-blended for 3 minutes to 5 minutes, and then potassium sodium silicate is added and stirred for 4 minutes to 6 minutes to obtain a mixture; the mixture is first dried at a low temperature of 200°C for 45 minutes to remove 99% of the moisture, and then sintered at a high temperature of 800°C for 60 minutes and sieved to obtain a granular wire electrode submerged arc welding sintering flux for high-temperature nickel-based alloy.

10. The wire electrode submerged arc welding sintering flux for high temperature nickel-based alloy according to claim 8, which has a particle size of 10-60 meshes.

11. The wire electrode submerged arc welding sintered flux for high temperature nickel-based alloy according to claim 1, which has the following weight ratio formula: 35 weight parts of fluorite, 18 weight parts of sillimanite, 22 weight parts of white corundum, 8 weight parts of magnesia, 5 weight parts of mica, 6 weight parts of cryolite, and 8 weight parts of clay; and its preparation method is as follows: the raw materials for the required sintered flux are weighed according to the formula, and after rechecking the total weight, they are put into a dry mixer and dry mixed for 2-10 minutes, and after dry mixing, they are poured into a wet mixer, and potassium silicate is added, which accounts for 24% of the total weight of the dry powder. Sodium is wet mixed for 2-10 minutes. After wet mixing is uniform, the wet powder is sent to the granulation plate through a conveyor belt for granulation. After granulation is completed, it is sent to a low-temperature furnace through a conveyor belt and dried at 180-230 ℃ for 35-60 minutes. Then it is lifted and sieved by a hoist. The semi-finished flux within the standard particle size range after screening is transported to a high-temperature kiln for sintering. It is sintered at a high temperature of 700-900 ℃ for 50-70 minutes. After leaving the kiln, it is cooled, lifted, and sieved with 10-50 meshes to obtain a granular wire electrode submerged arc welding sintering flux for high-temperature nickel-based alloy.

12. A method for preparing the wire electrode submerged arc welding sintering flux for high temperature nickel-based alloys according to any one of claims 1 to 11, It is characterized in that The method comprises the following steps: mixing seven kinds of fine powders of fluorite, sillimanite, white corundum, magnesia, mica, cryolite and clay in a formula ratio and dry-blending them for 2-10 minutes, then adding potassium sodium silicate and continuing to stir and mix for 2-10 minutes to obtain a mixture; first drying the mixture at a low temperature of 180-230°C for 35-60 minutes to remove 99% of the moisture, then sintering the mixture at a high temperature of 700-900°C for 50-70 minutes and sieving to obtain a granular wire electrode submerged arc welding sintering flux for high-temperature nickel-based alloy.

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