High crack resistance and wear resistance flux-cored wire and preparation method thereof

Abstract

The patent application discloses a high anti-crack wear-resistant flux-cored wire and a preparation method thereof, and mass ratio of raw materials of the flux-cored wire is as follows: electrolytic manganese 6-10%, metal chromium 28-34%, ferrotitanium 0.5-1.5%, tungsten powder 1-4%, nickel powder 5-9%, 45# ferrosilicon 4-8%, colloidal graphene 8-12%, molybdenum powder 8-12%, and the balance is iron powder.The flux-cored wire of the application is suitable for surfacing continuous casting roller, hot rolling roller and shaft with working temperature lower than 510 DEG C, and medium-temperature high-pressure stop valve sealing surface by adding elements such as C, W, Cr and Mo in the flux core and reasonably adjusting the proportion of the flux core powder, and has the advantages of fast melting speed, good weldability, strong surface wear resistance, hardness value basically reaching 50HRC and good crack resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of steel welding, and particularly relates to a highly crack-resistant and wear-resistant flux-cored welding wire and a preparation method thereof. Background Art

[0002] my country's manufacturing industry is currently undergoing structural transformation and upgrading, with the country transitioning from a manufacturing powerhouse to a manufacturing powerhouse. The continuous development and innovation of wear-resistant technology is bringing significant changes to the manufacturing industry, providing more flexible, efficient, and sustainable manufacturing methods and opening up more possibilities for innovative and customized production. With the rapid development of industry, many mechanical equipment and components, such as mining machinery, construction machinery, and metallurgical equipment, operate in high-wear environments. In these environments, components are easily worn due to friction, and traditional materials struggle to meet the wear resistance requirements. This has led to the development of wear-resistant welding technology, which allows wear-resistant alloys to be deposited onto the surfaces of easily worn components, achieving excellent wear resistance while maintaining the properties of the base material. Early welding techniques were relatively simple. With technological advancements, new welding methods, such as flux-cored arc welding and plasma arc deposition, have emerged. These methods offer more precise control over the welding process and improve the quality of the wear-resistant layer. However, the wear resistance and crack resistance of existing flux-cored welding wires need to be further improved. Summary of the Invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a highly crack-resistant and wear-resistant flux-cored welding wire and a preparation method thereof. The flux-cored welding wire of the present invention is suitable for surfacing continuous casting rolls, hot rolling rolls and shafts with an operating temperature below 510°C, as well as the sealing surface of medium-temperature and high-pressure stop valves. It has a fast surfacing melting speed, good weldability, and strong surface wear resistance. Its hardness value can basically reach 50HRC and has good crack resistance.

[0004] The technical solution adopted by the present invention is as follows: a highly crack-resistant and wear-resistant flux-cored welding wire, the mass ratio of the welding wire flux core raw materials is:

[0005] Electrolytic manganese: 6-10%;

[0006] Metallic chromium: 28-34%;

[0007] Ferrotitanium: 0.5-1.5%;

[0008] Tungsten powder: 1-4%;

[0009] Nickel powder: 5-9%;

[0010] 45# ferrosilicon: 4-8%;

[0011] Colloidal graphene: 8-12%;

[0012] Molybdenum powder: 8-12%;

[0013] The remainder is iron powder.

[0014] The working principle of the welding wire core material added in the present invention is:

[0015] Metallic chromium: It mainly plays the role of alloying, which can improve the strength and hardness of the weld, and has red hardness and high-temperature oxidation resistance.

[0016] Nickel powder: Appropriate nickel powder can improve plastic toughness, but too high Ni content will increase hot cracking sensitivity.

[0017] Ti has a strong binding force with oxygen and has a stronger deoxidizing ability than ferrosilicon, 2FeO+Ti→TiO2+2Fe. On the other hand, Ti can combine with nitrogen and reduce the gas in the weld metal.

[0018] Molybdenum powder: It mainly plays the role of alloying. Molybdenum powder is mainly added as an alloying agent to improve the hardenability and hardness of steel. The carbide formed is stronger than W and Cr.

[0019] Electrolytic manganese: Electrolytic manganese can be used as a deoxidizer. Appropriate manganese content is beneficial to the crack resistance of the molten metal.

[0020] Tungsten powder: It mainly plays the role of alloying, which can increase hardenability and form a strong and stable compound with carbon. Its hardness is second only to diamond.

[0021] 45# Ferrosilicon: In the process of additive melting, it mainly plays a deoxidation role. Silicon is chemically active and can graphitize metals.

[0022] Graphite: It is a key element to improve wear resistance and hardness. The carbide formed by graphite combined with Mo, Cr, W, and V has better wear resistance than the compounds combined with Mo, Cr, W, V and C elements.

[0023] Iron powder: dilutes other elements and improves the efficiency of welding as weld metal.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention rationally designs the ratio of various powders in the flux core formula and adds elements such as C, W, Cr, and Mo to the flux core, so that the welding wire of the present invention has good welding processability and crack resistance, is suitable for enhancing the wear resistance of the surface of the base material, has a fast melting rate, good weldability, strong surface wear resistance, and a hardness value of up to 50HRC and has good crack resistance.

[0026] 2. The raw materials used in the present invention are all high-grade raw materials with low content of S and P impurities, which is beneficial to improving the crack resistance of the molten metal.

[0027] As a preferred embodiment of the present invention, the diameter of the flux-cored welding wire is 0.8-1 mm. This solution uses small diameter welding wire to achieve the repair of the wear-resistant material surface under low input conditions.

[0028] As a preferred embodiment of the present invention, the flux-cored wire is a metal powder flux-cored wire welded using 75-85% Ar + CO2. This solution utilizes 75-85% Ar + CO2 welding, resulting in uniform melting, aesthetically pleasing welds, continuous buildup, and no slag removal, improving welding efficiency during production.

[0029] In a preferred embodiment of the present invention, the metallic chromium, ferrotitanium, tungsten powder, nickel powder, 45# ferrosilicon, colloidal graphene, and iron powder all utilize 140-220 mesh powder particles. In this solution, 140-220 mesh metallic chromium, ferrotitanium, tungsten powder, nickel powder, 45# ferrosilicon, colloidal graphene, and iron powder are used as raw materials for flux-cored welding wire. These fine powder particles enhance the wear resistance and crack resistance of the weld during welding, while also optimizing welding process performance, such as improving arc stability and reducing spatter and porosity, significantly improving the overall performance of the welding wire.

[0030] As a preferred embodiment of the present invention, the flux-cored welding wire includes a steel strip and a welding wire core, and the main chemical elements of the steel strip meet the following requirements: C≤0.030, Mn≤0.6%, Si≤0.5%, P≤0.020%, S content≤0.020%, Ni≤0.6%, Mo≤0.5%, Cr:11.5-13.5%, Cu≤0.2%; the welding wire core accounts for 11.5-12.5% ​​of the total mass of the flux-cored welding wire.

[0031] In this solution, the high chromium content (11.5-13.5%) in the steel strip imparts excellent corrosion and oxidation resistance to the welding wire. Simultaneously, low sulfur and phosphorus content helps reduce welding defects and improve weld toughness. The flux core, which accounts for 11.5-12.5% ​​of the total mass, provides stable welding process performance, such as arc stability, minimal spatter, and aesthetically pleasing weld formation. Furthermore, alloying elements (such as nickel and molybdenum) in the flux core further optimize the mechanical properties and crack resistance of the weld. This flux-cored wire is suitable for a variety of welding processes and materials, offering high deposition efficiency and excellent all-position welding capabilities.

[0032] The embodiment of the present invention further provides a method for preparing a highly crack-resistant and wear-resistant flux-cored welding wire, comprising the following steps:

[0033] S1: Pre-mix and weigh the raw materials of the welding wire core, and control the particle size of metallic chromium, ferrotitanium, tungsten powder, nickel powder, 45# ferrosilicon, colloidal graphene, and iron powder to 140-220 mesh;

[0034] S2: Mix all the raw materials evenly and bake at 220-270℃, keep warm for 2-3 hours, and stir the powder after it cools to no higher than 60℃ for 30-60 minutes;

[0035] S3: Through the forming process, the powder is loaded into the welding wire steel strip at a filling rate of 11.5-12.5%. When the forming line is off, five 20-30cm welding wires are cut to test the filling rate;

[0036] S4: The uniformly mixed powder is filled into the welding wire steel strip at a filling rate of 11.5-12.5% ​​through a forming process, rolled into shape, and finely drawn to a specification of 0.8-1 mm.

[0037] Compared with the existing technology, the beneficial effects of this solution are:

[0038] 1. By rationally designing the flux core formula of the welding wire, adding wear-resistant enhancing ingredients such as metallic chromium, ferrotitanium, and tungsten powder, optimizing the ratio of various powders in the flux core formula, and adding elements such as C, W, Cr, and Mo to the flux core, the welding wire can form a weld with high hardness and high wear resistance during the welding process, while significantly reducing the crack sensitivity of the weld.

[0039] 2. The flux core, which has been baked and stirred at 220-270℃, combined with strictly controlled filling rate and fine drawing process, ensures arc stability, low spatter and good slag removal during welding, thus improving welding quality and efficiency.

[0040] 3. The alloying elements and graphene in the flux core can improve the microstructure of the weld during the welding process, enhance the toughness and impact resistance of the weld, and make it suitable for welding scenarios requiring high strength and high wear resistance. DETAILED DESCRIPTION

[0041] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention is capable of various variations in different embodiments without departing from the scope of the present invention, and the descriptions are intended to be illustrative rather than limiting.

[0042] The flux-cored welding wire of the present invention is composed of a stainless steel SUS410L steel strip and a flux core. The steel strip has a specification of 0.4 mm×10 mm. The main chemical elements of the steel strip meet the following requirements: C≤0.030, Mn≤0.6%, Si≤0.5%, P≤0.020%, S content≤0.020%, Ni≤0.6%, Mo≤0.5%, Cr: 11.5-13.5%, Cu≤0.2%, and the flux core filling rate is 11.5-12.5%.

[0043] Examples 1-3

[0044] The flux core proportions of the welding wires of Examples 1-3 of the present invention are shown in Table 1.

[0045] The method for preparing a highly crack-resistant and wear-resistant flux-cored welding wire according to an embodiment of the present invention comprises the following steps:

[0046] S1: Pre-mix and weigh the raw materials of the welding wire core, and control the particle size of metallic chromium, ferrotitanium, tungsten powder, nickel powder, 45# ferrosilicon, colloidal graphene, and iron powder to 140-220 mesh;

[0047] S2: Mix all the raw materials evenly and bake at 220-270℃ for 2-3 hours. Stir the powder until it cools to no higher than 60℃ for 30-60 minutes.

[0048] S3: Through the forming process, the powder is loaded into the welding wire steel strip at a filling rate of 11.5-12.5%. When the forming line is off, five 20-30cm welding wires are cut to test the filling rate;

[0049] S4: The uniformly mixed powder is filled into the welding wire steel strip at a filling rate of 11.5-12.5% ​​through a forming process, rolled into shape, and finely drawn to a specification of 0.9 mm.

[0050] Table 1 Welding wire flux core ratio of Examples 1-3

[0051] Core ratio Example 1 Example 2 Example 3 Electrolytic manganese: 6-10% 6 8 10 Metallic chromium: 28-34% 28 31 34 Ferrotitanium: 0.5-1.5% 1.5 1 0.5 Tungsten powder: 1-4% 1 2.5 4 Nickel powder: 5-9% 5 7 9 45# ferrosilicon: 4-8% 4 6 8 Colloidal graphene: 8-12% 12 10 8 Molybdenum powder: 8-12% 12 10 8 die-hard fans The remainder is iron powder The remainder is iron powder The remainder is iron powder

[0052] Heap melting test:

[0053] The wear-resistant metal powder cored flux-cored welding wires obtained in Examples 1-3 were subjected to a fusion test using 75-85% Ar+CO2 gas shielded welding. The test results of the chemical composition (mass fraction %) of the fusion metal are shown in Table 3.

[0054] Table 3 Chemical composition content in Examples 1-3

[0055] Chemical elements C Mn Si S P Cr Ni Mo Example 1 0.155 0.84 0.44 0.03 0.05 14.65 0.68 1.01 Example 2 0.175 0.86 0.50 0.004 0.05 14.9 0.75 1.12 Example 3 0.182 0.95 0.55 0.004 0.06 15.2 0.8 1.23

[0056] Table 4 Surface hardness of melted metal

[0057] Example HRC Example 1 53 48 52 Example 2 47 54 55 Example 3 50 54 53

[0058] It can be seen from Table 4 that the hardness value of the molten metal obtained from the wear-resistant metal powder core flux core of this embodiment is good and the value is stable.

[0059] In addition, the molten metal obtained in the above Examples 1-3 was subjected to a radiographic flaw detection test, and the result was Level I.

[0060] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A highly crack-resistant and wear-resistant flux-cored welding wire, characterized in that: The mass ratio of the welding wire core raw materials is: Electrolytic manganese: 6-10%; Metallic chromium: 28-34%; Ferrotitanium: 0.5-1.5%; Tungsten powder: 1-4%; Nickel powder: 5-9%; 45# ferrosilicon: 4-8%; Colloidal graphene: 8-12%; Molybdenum powder: 8-12%; The remainder is iron powder; The flux-cored welding wire includes a steel strip and a welding wire core. The main chemical elements of the steel strip meet the following requirements: C≤0.030, Mn≤0.6%, Si≤0.5%, P≤0.020%, S content≤0.020%, Ni≤0.6%, Mo≤0.5%, Cr: 11.5-13.5%, and Cu≤0.2%. The welding wire core accounts for 11.5-12.5% ​​of the total mass of the flux-cored welding wire.

2. The high crack resistance and wear resistance flux-cored welding wire according to claim 1, characterized in that: The diameter specification of the flux-cored welding wire is 0.8-1 mm.

3. The high crack resistance and wear resistance flux-cored welding wire according to claim 2, characterized in that: The flux-cored welding wire is a metal powder type flux-cored welding wire, which is welded using 75-85% Ar+CO2.

4. The high crack resistance and wear resistance flux-cored welding wire according to claim 3, characterized in that: The metallic chromium, ferrotitanium, tungsten powder, nickel powder, 45# ferrosilicon, colloidal graphene and iron powder all adopt 140-220 mesh powder particles.

5. The method for preparing a highly crack-resistant and wear-resistant flux-cored welding wire according to any one of claims 1 to 4, wherein: The following steps are involved: S1: Pre-mix and weigh the raw materials of the welding wire core, and control the particle size of metallic chromium, ferrotitanium, tungsten powder, nickel powder, 45# ferrosilicon, colloidal graphene, and iron powder to 140-220 mesh; S2: Mix all the raw materials evenly and bake at 220-270℃, keep warm for 2-3 hours, and stir the powder after it cools to no higher than 60℃ for 30-60 minutes; S3: Through the forming process, the powder is loaded into the welding wire steel strip at a filling rate of 11.5-12.5%. When the forming line is off, five 20-30cm welding wires are cut to test the filling rate; S4: Through the forming process, the mixed powder is filled into the welding wire steel strip at a filling rate of 11.5-12.5%, rolled into shape, and finely drawn to a specification of 0.8-1mm.