A self-shielding alloy powder for solid wire open arc surfacing and its preparation method and application

Abstract

The present invention provides a self-shielding alloy powder for open arc surfacing welding of a solid welding wire, as well as a preparation method and application thereof, belonging to the technical field of open arc surfacing materials. The self-shielding alloy powder for open arc surfacing welding of a solid welding wire of the present invention comprises the following components, calculated by mass percentage: C 11.0% to 15.8%, B 1.0% to 2.0%, Si 1.0% to 2.0%, Mn 1.5% to 2.8%, Al 2.0% to 4.0%, Cr 18.0% to 24.0%, Ti 7.2% to 8.5%, CaF 3% to 4%, and rare earth elements 0.08% to 0.4%, with the balance being Fe. The powder is prepared by mixing Mn13# steel with MnO and Cr3C2, desulfurizing and dephosphorizing the mixture, adding B, Al, Ti, Si, and the rare earth elements, and then smelting the mixture, followed by atomizing granulation and drying. The self-shielding alloy powder for open arc surfacing of solid welding wire of the present invention is specially used for Mn13# steel under low stress impact, and ensures the hardness, wear resistance, self-lubrication, oxidation resistance, metallurgical bonding, etc. of the surfacing layer under low stress impact. At the same time, the wettability of the powder is improved, and the cracking, porosity and other problems of the surfacing layer during the open arc surfacing process are suppressed.

Description

Technical Field

[0001] The present invention belongs to the technical field of open arc surfacing materials, and in particular relates to a self-shielding alloy powder for open arc surfacing of a solid welding wire, and a preparation method and application thereof. Background Art

[0002] Mn13# steel is a widely used wear-resistant steel used in a variety of key components. It resists wear through work hardening. However, in practice, insufficient work hardening often leads to surface wear and corrosion failures. Therefore, maintaining the overall strength and toughness of the material while improving its surface wear resistance, corrosion resistance, and other specific performance characteristics has become a research priority.

[0003] Solid wire open arc cladding powder technology refers to placing the selected cladding powder on the substrate using different addition methods, using the welding wire as a heat source to melt the powder material, allowing the material to be quickly heated to a molten state, and then forming a surface wear-resistant layer with good metallurgical bonding after fusing with the substrate surface. This technology can be used to process and modify the surface of metal-based parts, improving the hardness, wear resistance, corrosion resistance, heat resistance, oxidation resistance and other properties of the metal surface.

[0004] The performance of solid wire open arc surfacing powder is affected by many factors, and powder material is one of the most important factors. In order to obtain a good crack-free surfacing layer, the surfacing powder must not only have good self-fluxing properties, but also good metallurgical bonding properties. This requires that the surfacing powder and the welding wire composition must be compatible. If the element content of the powder material and the welding wire cannot complement each other, or the gap between the wire feed amount and the powder dosage is too large, the rapid cooling and heating characteristics of open arc surfacing will cause problems such as pores, cracks, and a large number of inclusions. Secondly, the powder material must have good self-protection properties, because solid wire usually requires the introduction of shielding gas for welding. When surfacing is performed without the introduction of shielding gas, the powder composition needs to have good self-protection properties, otherwise it will have a greater impact on the forming after surfacing.

[0005] Currently, solid wire open arc hardfacing powders are mostly formulated commercial powders. However, specialized solid wire open arc hardfacing powders for specific metals are in short supply. Existing wear-resistant hardfacing layers are mostly created using self-shielded flux-cored wire. This wire undergoes a complex process involving core filling, drawing, and rolling, and is composed of a single component. There is a lack of technology to improve substrate properties through the use of self-shielded alloy powders for solid wire open arc hardfacing. Therefore, the present invention proposes a self-shielded alloy powder for solid wire open arc hardfacing, as well as its preparation method and application. Summary of the Invention

[0006] The purpose of the present invention is to solve the friction and wear caused by insufficient work hardening of Mn13# steel under low stress impact, and proposes a solid welding wire open arc surfacing self-shielding alloy powder and its preparation method and application. The solid welding wire open arc surfacing self-shielding alloy powder of the present invention is an Fe-based alloy powder, which is similar to the component composition of the Mn13# steel matrix. The solid welding wire open arc surfacing self-shielding alloy powder of the present invention is specially used for Mn13# steel under low stress impact, ensuring the hardness, wear resistance, self-lubrication, oxidation resistance, metallurgical bonding, etc. of the surfacing layer under low stress impact. At the same time, the wettability of the powder is improved, and the cracking, porosity and other problems of the surfacing layer during the open arc surfacing process are suppressed.

[0007] To achieve the above objectives, the present invention provides the following technical solutions:

[0008] One of the technical solutions of the present invention:

[0009] A self-shielding alloy powder for open arc surfacing welding of a solid welding wire comprises the following components, calculated by mass percentage: C11.0%-15.8%, B 1.0%-2.0%, Si 1.0%-2.0%, Mn 1.5%-2.8%, Al 2.0%-4.0%, Cr18.0%-24.0%, Ti 7.2%-8.5%, CaF 3%-4% and rare earth elements 0.08%-0.4%, with the balance being Fe.

[0010] Preferably, the following components are included, calculated by mass percentage: C 12.0% to 12.5%, B 1.2% to 1.5%, Si 1.2% to 1.4%, Mn 1.9% to 2.2%, Al 2.2% to 2.8%, Cr 19.0% to 19.5%, Ti 7.5% to 8.0%, CaF 3.8% to 4.0% and rare earth elements 0.1% to 0.15%, and the balance is Fe.

[0011] More preferably, the following components are included, calculated by mass percentage: C 12.3%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 19.0%, Ti 7.6%, CaF 3.9% and rare earth elements 0.12%, with the balance being Fe.

[0012] Preferably, the rare earth element is at least one of La, Ce, and Y.

[0013] Preferably, the solid wire open arc surfacing self-shielding alloy powder has an average particle size of 60 to 90 μm, a spherical micromorphology, uniform size, and good fluidity, thereby providing it with excellent surfacing performance.

[0014] The second technical solution of the present invention:

[0015] A method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding comprises the following steps:

[0016] Mn13# steel is mixed with MnO and Cr3C2 and heated at high temperature for reaction desulfurization and dephosphorization, and then cooled to obtain a main raw material. B, Al, Ti, Si, CaF and rare earth elements are added to the main raw material according to mass percentage and mixed and smelted, and then the solid welding wire open arc surfacing self-shielding alloy powder is obtained through atomization granulation and drying.

[0017] Preferably, the temperature of the mixed smelting is 3600-3900° C., and the temperature is kept for 10-11 hours.

[0018] Preferably, the medium for atomization granulation is an inert gas at -20°C to -10°C, and the pressure for atomization granulation is 3.8 to 4.2 MPa. More preferably, the medium for atomization granulation is an inert gas at -15°C to -11°C, and the pressure for atomization granulation is 4.0 MPa.

[0019] Preferably, the inert gas is composed of argon and nitrogen in a volume ratio of (9-10):0.6, and more preferably, the volume ratio of argon and nitrogen is 9.8:0.6.

[0020] Preferably, after the atomization granulation is completed, the mixture is cooled to room temperature under an inert atmosphere at normal temperature.

[0021] More specifically, the method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding comprises the following steps:

[0022] Step 1: Desulfurization and dephosphorization: Heat the Mn13# steel to a liquid state, add MnO and Cr3C2 to react and remove the phosphorus and sulfur impurities;

[0023] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, and rare earth alloy powders according to the weight percentage of each component;

[0024] Step 3: Melting: Melt the raw materials prepared in step 2 at 3600-3900°C for 10 hours to obtain alloy melt;

[0025] Step 4, atomization: The alloy melt obtained in step 3 is further atomized and granulated, the atomizing medium is an inert gas at -20°C to -10°C (composed of argon and nitrogen in a volume ratio of (9-10) : 0.6), and the atomization pressure is 3.8-4.2 MPa; after the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried, and then sieved to obtain the solid welding wire open arc surfacing self-shielding alloy powder.

[0026] The third technical solution of the present invention:

[0027] The invention discloses an application of the self-shielding alloy powder for solid welding wire open arc surfacing welding in Mn13# steel solid welding wire surfacing welding.

[0028] Preferably, during the surfacing welding process of Mn13# steel solid welding wire, the weight ratio of the solid welding wire used to the solid welding wire open arc surfacing self-shielding alloy powder is 1:(1.2-1.5).

[0029] Compared with the prior art, the present invention has the following advantages and technical effects:

[0030] (1) The solid wire open arc surfacing self-shielding alloy powder obtained by the present invention is used in Mn13# steel, so that the main components of the surfacing layer are less different from those of the substrate, so that it has good low stress impact wear resistance, metallurgical bonding and physical and chemical properties, and reduces the dilution rate of the surfacing layer during the surfacing process.

[0031] (2) The present invention obtains a self-shielding alloy powder for solid wire open arc surfacing by regulating C and Ti, and regulates a suitable equivalent value, thereby increasing the plasticity and toughness of the surfacing layer, inhibiting the cracking of the surfacing layer and the crack propagation rate, and reducing the occurrence of post-weld problems such as pores and slag inclusions; at the same time, adding a trace amount of rare earth elements to the powder can play a role in refining grains, purifying the melt, and strengthening grain boundaries.

[0032] (3) The self-protective alloy powder for open arc surfacing of solid welding wire of the present invention generates hard phases M7C3, TiC, TiN, and self-lubricating phases Al2O3 and SiC during the preparation process of the surfacing layer, thereby improving the wear resistance and self-lubricating properties of the surfacing layer.

[0033] (4) The size of the self-shielding alloy powder for solid wire open arc surfacing obtained by the present invention is about 60 to 90 μm, which greatly improves the density of the surfacing layer and improves the quality of the surfacing layer.

[0034] (5) In the method for preparing self-shielded alloy powder by solid wire open arc surfacing proposed in the present invention, argon gas at -20°C to -10°C is used for the first time in the atomization step, and a small amount of nitrogen is introduced during atomization to further reduce the impurity content of the alloy powder. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 This is a microscopic morphology of the self-shielding alloy powder for open arc surfacing welding of a cored wire prepared in Example 1 of the present invention;

[0037] Figure 2This is a morphology image of the cross section of the surfacing layer obtained by open arc surfacing with the self-shielded alloy powder prepared in Example 1 of the present invention (the scale is 200 μm);

[0038] Figure 3 This is a morphology image of the cross section of the surfacing layer obtained by open arc surfacing with the self-shielded alloy powder prepared in Example 1 of the present invention (the scale is 50 μm);

[0039] Figure 4 This is a SEM image of the wear morphology of the surfacing layer after friction and wear test after surfacing with the self-shielding alloy powder by open arc surfacing with a cored wire prepared in Example 1 of the present invention;

[0040] Figure 5 This is the SEM image of the wear morphology of the matrix Mn13# steel after friction and wear test;

[0041] Figure 6 Cross-section diagram of the coating for wire gas shielded cladding;

[0042] Figure 7 This is a cross-sectional view of the coating after open arc surfacing of the self-shielding alloy powder cored welding wire prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0043] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0044] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0045] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0046] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be illustrative only.

[0047] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0048] An embodiment of the present invention provides a self-shielding alloy powder for solid wire open arc surfacing welding, which includes the following components, calculated by mass percentage: C 11.0% to 15.8%, B 1.0% to 2.0%, Si 1.0% to 2.0%, Mn 1.5% to 2.8%, Al 2.0% to 4.0%, Cr 18.0% to 24.0%, Ti 7.2% to 8.5%, CaF 3% to 4% and rare earth elements 0.08% to 0.4%, with the balance being Fe.

[0049] In a preferred embodiment of the present invention, the self-shielding alloy powder for solid wire open arc surfacing welding comprises the following components, calculated by mass percentage: C 12.0% to 12.5%, B 1.2% to 1.5%, Si 1.2% to 1.4%, Mn 1.9% to 2.2%, Al 2.2% to 2.8%, Cr 19.0% to 19.5%, Ti 7.5% to 8.0%, CaF 3.8% to 4.0%, and rare earth elements 0.1% to 0.15%, with the balance being Fe. More preferably, the self-shielding alloy powder comprises the following components, calculated by mass percentage: C 12.3%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 19.0%, Ti 7.6%, CaF 3.9%, and rare earth elements 0.12%, with the balance being Fe.

[0050] In a preferred embodiment of the present invention, the rare earth element is at least one of La, Ce, and Y, preferably Ce.

[0051] In a preferred embodiment of the present invention, the average particle size of the solid wire open arc surfacing self-shielding alloy powder is 60 to 90 μm, the microscopic morphology is spherical, the size is uniform, and it has good fluidity, which greatly improves the density of the surfacing layer and improves the quality of the surfacing layer.

[0052] The self-shielding alloy powder for solid wire open arc hardfacing obtained in this embodiment of the present invention ensures that the primary components of the hardfacing layer are minimally different from those of the Mn13# steel matrix, resulting in excellent low-stress impact wear resistance, metallurgical bonding, and physical and chemical properties, while reducing the dilution rate of the hardfacing layer during the hardfacing process. Furthermore, the carbon and titanium contents are regulated to appropriate equivalent values, increasing the plasticity and toughness of the hardfacing layer, inhibiting cracking and crack propagation rates, and reducing post-weld problems such as porosity and slag inclusions. Furthermore, the addition of trace amounts of rare earth elements to the powder can refine grains, purify the melt, and strengthen grain boundaries.

[0053] The embodiment of the present invention further provides a method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding, comprising the following steps:

[0054] Mn13# steel is mixed with MnO and Cr3C2 and heated at high temperature for reaction desulfurization and dephosphorization, and then cooled to obtain a main raw material. B, Al, Ti, Si, CaF and rare earth elements are added to the main raw material according to mass percentage and mixed and smelted, and then the solid welding wire open arc surfacing self-shielding alloy powder is obtained through atomization granulation and drying.

[0055] In a preferred embodiment of the present invention, the Mn13# steel, also known as high manganese steel or wear-resistant steel, is a special steel with manganese as the main alloying element, which has excellent wear resistance and impact resistance. Iron (Fe) in Mn13# steel is its matrix element. In addition, Mn13# steel mainly includes the following elements in percentage by mass: C 0.90% to 1.50%, Mn10.0% to 15.0%, Si 0.30% to 0.80, P≤0.035%, S≤0.035%. More specifically, the Mn13# steel used in the embodiment of the present invention was purchased from Shandong Hongshen Metal Co., Ltd., and the specific element composition is: C 0.93%, Si 0.39%, Mn12.5%, S 0.008%, P 0.015%, and the balance is Fe.

[0056] In a preferred embodiment of the present invention, the temperature of the mixed smelting is 3600-3900° C., and the temperature is kept for 10-11 hours.

[0057] In a preferred embodiment of the present invention, the medium for atomization granulation is an inert gas at -20°C to -10°C, and the pressure for atomization granulation is 3.8 to 4.2 MPa. More preferably, the medium for atomization granulation is an inert gas at -15°C to -11°C, and the pressure for atomization granulation is 4.0 MPa.

[0058] In a preferred embodiment of the present invention, the inert gas is composed of argon and nitrogen in a volume ratio of (9-10) : 0.6. More preferably, the volume ratio of argon and nitrogen is 9.8: 0.6. Introducing a small amount of nitrogen during atomization can further reduce the impurity content of the alloy powder.

[0059] In a preferred embodiment of the present invention, after the atomization granulation is completed, the mixture is cooled to room temperature under an inert atmosphere at normal temperature.

[0060] The embodiment of the present invention further proposes the application of a self-shielding alloy powder for solid wire open arc surfacing welding in the surfacing welding of Mn13# steel solid wire.

[0061] In a preferred embodiment of the present invention, during the surfacing welding process of Mn13# steel solid welding wire, the weight ratio of the solid welding wire used to the solid welding wire open arc surfacing self-shielding alloy powder is 1:(1.2-1.5).

[0062] In a preferred embodiment of the present invention, the solid welding wire is a welding wire with a grade of 1Cr17. The welding wire with a grade of 1Cr17 is a ferritic stainless steel material, and its main components include carbon (C), silicon (Si), manganese (Mn), phosphorus (P), sulfur (S) and chromium (Cr). The specific content is: C≤0.12%, Si≤1.00%, Mn≤1.00%, P≤0.040%, S≤0.030%, Cr16.00~18.00%, Ni≤0.60%. More specifically, the welding wire with a grade of 1Cr17 used in the embodiment of the present invention was purchased from Sichuan Atlantic Welding Materials Co., Ltd.

[0063] In the embodiments of the present invention, "normal temperature" and "room temperature" both refer to "25±2°C".

[0064] The technical solution of the present invention is further illustrated by the following examples.

[0065] Example 1

[0066] The self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment includes the following components by mass percentage: C12.3%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 19.0%, Ti 7.6%, CaF 3.9% and rare earth element (Ce) 0.12%, with the balance being Fe.

[0067] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0068] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0069] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0070] Step 3: Melting: Melt the raw materials prepared in step 2 at 3800°C for 10 hours to obtain alloy melt;

[0071] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -10°C (composed of argon and nitrogen with a volume ratio of 9.8:0.6), and the atomization pressure is 4 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid welding wire open arc surfacing self-shielded alloy powder with an average particle size of 60 to 80 μm.

[0072] The average particle size of the cored wire open arc surfacing self-shielding alloy powder prepared in this embodiment is 60-80 μm. The powder has good fluidity during the surfacing process. The obtained powder is subjected to SEM electron microscope analysis, and the micromorphology is shown in FIG. Figure 1 , it can be seen that the powder has regular shape, uniform size and very good surfacing performance.

[0073] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was carried out using Mn13# steel as the matrix. The process steps are as follows:

[0074] (1) Surface pretreatment: First, grind and clean the surface of the base Mn13# steel to remove surface stains, then clean the surface with acetone and blow dry after cleaning to reduce the impact of external impurities on the surfacing layer;

[0075] (2) Solid wire surfacing: The surfacing was performed using a welding machine and a robotic arm combination device. The prefabricated powder spreading method was adopted, and no protective atmosphere was required. The solid wire was 1Cr17. The process parameters for surfacing were welding current 260A, surfacing speed 100mm / min, powder spreading mass 25g, dry extension length 12mm, and welding gun swing frequency 0.3Hz.

[0076] The morphology of the cross section of the surfacing layer obtained by open arc surfacing of the self-shielded alloy powder prepared by the core welding wire in this embodiment at different magnifications is shown in FIG. Figure 2 and Figure 3As can be seen from the metallographic image, the evenly distributed columnar crystals, primarily representing austenite, are present. The dispersed carbides, typically chromium carbide particles, provide reliable wear resistance for the overlay layer. Furthermore, the overlay layer achieves a good metallurgical bond with the base material. This is because during the overlay preparation process, the cored wire open arc overlay of the self-shielding alloy powder generates hard phases such as M7C3, TiC, and TiN, as well as self-lubricating phases such as Al2O3 and SiC, enhancing the wear resistance and self-lubricating properties of the overlay layer.

[0077] The hardness of the surfacing layer was tested with reference to the method of GB / T 230.1-2009. The results showed that the hardness of the surfacing layer after surfacing in this embodiment was 50-55 HRC, while the hardness of ordinary Mn13# steel (base Mn13# steel) was about 30-35 HRC. The hardness directly affects the wear resistance. The higher the hardness, the better the wear resistance of the surfacing layer. In addition, the surfacing layer of the present invention has no obvious impurities and a tight internal structure, which greatly reduces the occurrence of defects inside the wear-resistant layer and greatly ensures the wear resistance of the wear-resistant layer.

[0078] The friction and wear test was conducted on the cladding layer after cladding in this embodiment and the base Mn13# steel (referring to ISO 7148-1:1988), with a wear time of 1 hour, a load of 50N, and a wear frequency of 2Hz. The grinding balls were ceramic silicon carbide balls with a diameter of 5mm. The wear morphology of the cladding layer after cladding in this embodiment after the friction and wear test was shown in the SEM image. Figure 4 The wear morphology SEM image of the matrix Mn13# steel after friction and wear test is shown in Figure 5 , it can be seen that the base Mn13# steel exhibited flaking and furrowing during wear, while the coating after hardfacing in this example exhibited only slight furrowing. Under the same wear conditions, the wear weight loss of the hardfacing layer in this example was 8.5 mg, significantly less than the 30 mg weight loss of the base Mn13# steel, demonstrating that the hardfacing layer prepared in this example has superior wear resistance to the base.

[0079] Example 2

[0080] The self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment includes the following components by mass percentage: C12.3%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 19.0%, Ti 7.6%, CaF 3.9% and rare earth element (Ce) 0.12%, with the balance being Fe.

[0081] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0082] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0083] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0084] Step 3: Melting: Melt the raw materials prepared in step 2 at 3800°C for 10 hours to obtain alloy melt;

[0085] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -15°C (composed of argon and nitrogen with a volume ratio of 9.8:0.6), and the atomization pressure is 4.2 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid welding wire open arc surfacing self-shielded alloy powder with an average particle size of 60 to 80 μm.

[0086] The self-shielding alloy powder for cored wire open arc surfacing prepared in this embodiment has an average particle size of 60 to 80 μm, and the powder has good fluidity during the surfacing process.

[0087] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0088] The results show that the hardness of the surfacing layer after surfacing in this embodiment is 52-58 HRC, and the weight loss of the surfacing layer is 7.8 mg.

[0089] Example 3

[0090] The self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment includes the following components by mass percentage: C12.3%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 23.0%, Ti 8.4%, CaF 3.9% and rare earth element (Ce) 0.12%, with the balance being Fe.

[0091] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0092] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0093] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0094] Step 3: Melting: Melt the raw materials prepared in step 2 at 3900°C for 11 hours to obtain alloy melt;

[0095] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -15°C (composed of argon and nitrogen with a volume ratio of 9.8:0.6), and the atomization pressure is 4.1 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid welding wire open arc surfacing self-shielded alloy powder with an average particle size of 60 to 85 μm.

[0096] The self-shielding alloy powder for cored wire open arc surfacing prepared in this embodiment has an average particle size of 60 to 85 μm, and has good fluidity during the surfacing process.

[0097] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0098] The results show that the hardness of the surfacing layer after surfacing in this embodiment is 54-59HRC, the weight loss of the surfacing layer is 7.2mg, and the wear resistance is higher than that of Example 1. This is mainly because the hard phase generated by the addition of Ti and Cr elements greatly improves the hardness and wear resistance of the surfacing layer.

[0099] Example 4

[0100] The self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment includes the following components by mass percentage: C12.3%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 19.0%, Ti 7.6%, CaF 3.9% and rare earth element (Ce) 0.12%, with the balance being Fe.

[0101] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0102] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0103] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0104] Step 3: Melting: Melt the raw materials prepared in step 2 at 3900°C for 10 hours to obtain alloy melt;

[0105] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -15°C (composed of argon and nitrogen with a volume ratio of 9.8:0.6), and the atomization pressure is 4 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid welding wire open arc surfacing self-shielding alloy powder with an average particle size of 60 to 90 μm.

[0106] The self-shielding alloy powder for cored wire open arc surfacing prepared in this embodiment has an average particle size of 60 to 90 μm, and the powder has good fluidity during the surfacing process.

[0107] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0108] The results show that the hardness of the surfacing layer after surfacing in this embodiment is 57-61 HRC, and the weight loss of the surfacing layer is 6.6 mg.

[0109] Example 5

[0110] The self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment includes the following components by mass percentage: C12.5%, B 1.2%, Si 1.4%, Mn 1.9%, Al 2.8%, Cr 19.0%, Ti 7.5%, CaF 4.0% and rare earth element (La) 0.15%, and the balance is Fe.

[0111] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0112] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0113] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0114] Step 3: Melting: Melt the raw materials prepared in step 2 at 3900°C for 10 hours to obtain alloy melt;

[0115] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -10°C (composed of argon and nitrogen in a volume ratio of (18:1.2) and the atomization pressure is 4.2 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid wire open arc surfacing self-shielded alloy powder with an average particle size of 60 to 75 μm.

[0116] The self-shielding alloy powder for cored wire open arc surfacing prepared in this embodiment has an average particle size of 60 to 75 μm, and has good fluidity during the surfacing process.

[0117] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0118] The results show that the hardness of the surfacing layer after surfacing in this embodiment is 58-61 HRC, and the weight loss of the surfacing layer is 6.5 mg.

[0119] Example 6

[0120] In this embodiment, the self-shielding alloy powder for solid wire open arc surfacing welding includes the following components by mass percentage: C12.0%, B 1.5%, Si 1.2%, Mn 2.2%, Al 2.2%, Cr 19.5%, Ti 8.0%, CaF 3.8% and rare earth element (Y) 0.1%, with the balance being Fe.

[0121] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0122] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0123] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0124] Step 3: Melting: Melt the raw materials prepared in step 2 at 3600°C for 10 hours to obtain alloy melt;

[0125] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -20°C (composed of argon and nitrogen with a volume ratio of 20:1.2), and the atomization pressure is 3.8 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid welding wire open arc surfacing self-shielding alloy powder with an average particle size of 60 to 72 μm.

[0126] The self-shielding alloy powder for cored wire open arc surfacing welding prepared in this embodiment has an average particle size of 60 to 72 μm, and the powder has good fluidity during the surfacing process.

[0127] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0128] The results show that the hardness of the surfacing layer after surfacing in this embodiment is 58-60 HRC, and the weight loss of the surfacing layer is 6.6 mg.

[0129] Example 7

[0130] In this embodiment, the self-shielding alloy powder for solid wire open arc surfacing welding includes the following components by mass percentage: C15.8%, B 2.0%, Si 1.0%, Mn 1.5%, Al 4.0%, Cr 24.0%, Ti 7.2%, CaF 4% and rare earth element (Ce) 0.4%, with the balance being Fe.

[0131] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0132] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0133] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0134] Step 3: Melting: Melt the raw materials prepared in step 2 at 3600°C for 10 hours to obtain alloy melt;

[0135] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -20°C (composed of argon and nitrogen with a volume ratio of 9.8:0.6), and the atomization pressure is 3.8 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid welding wire open arc surfacing self-shielded alloy powder with an average particle size of 60 to 68 μm.

[0136] The self-shielding alloy powder for cored wire open arc surfacing prepared in this embodiment has an average particle size of 60 to 68 μm, and the powder has good fluidity during the surfacing process.

[0137] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0138] The results show that the hardness of the surfacing layer after surfacing in this embodiment is 58-59 HRC, and the weight loss of the surfacing layer is 6.5 mg.

[0139] Example 8

[0140] In this embodiment, the self-shielding alloy powder for solid wire open arc surfacing welding includes the following components by mass percentage: C11.0%, B 1.0%, Si 2.0%, Mn 2.8%, Al 2.0%, Cr 18.0%, Ti 8.5%, CaF 3% and rare earth element (La) 0.08%, with the balance being Fe.

[0141] The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding in this embodiment specifically comprises the following steps:

[0142] Step 1: Desulfurization and dephosphorization: Heat Mn13# steel to 1600℃ until it is in liquid state, add 8% MnO and 10% Cr3C2 of Mn13# steel mass to react and remove phosphorus and sulfur impurities;

[0143] Step 2: Ingredients: Prepare desulfurized and dephosphorized Mn13# steel and B, Al, Ti, Si, CaF and rare earth alloy powders according to the weight percentage of the above components;

[0144] Step 3: Melting: Melt the raw materials prepared in step 2 at 3900°C for 11 hours to obtain alloy melt;

[0145] Step 4: Atomization: The alloy melt obtained in step 3 is further atomized and granulated. The atomizing medium is an inert gas at -10°C (composed of argon and nitrogen with a volume ratio of 20:1.2), and the atomization pressure is 4.0 MPa. After the atomization is completed, it is cooled to room temperature under an inert atmosphere at room temperature, dried and sieved to obtain a solid welding wire open arc surfacing self-shielding alloy powder with an average particle size of 60 to 65 μm.

[0146] The self-shielding alloy powder for cored wire open arc surfacing prepared in this embodiment has an average particle size of 60 to 65 μm, and the powder has good fluidity during the surfacing process.

[0147] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0148] The results show that the hardness of the surfacing layer after surfacing in this embodiment is 58HRC, and the weight loss of the surfacing layer is 6.4mg.

[0149] Comparative Example 1

[0150] The same as Example 1, except that the solid wire open arc surfacing self-shielding alloy powder in this comparative example includes the following components by mass percentage: C 17.9%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 19.0%, Ti 5.4%, CaF 3.9% and rare earth elements 0.12%, and the balance is Fe.

[0151] The average particle size of the cored wire open arc surfacing self-shielding alloy powder prepared in this comparative example is 60 to 70 μm.

[0152] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0153] The results show that the hardness of the surfacing layer after surfacing in this comparative example is 54HRC, and the weight loss of the surfacing layer is 7.7mg. This is because the ratio of the C and Ti elements changes. The increase in C element leads to increased gasification and burnout, which reduces the amount of C element that can migrate to the Ti element for combination. Moreover, the reduction in Ti element reduces the wear-resistant TiC carbides generated by the two elements, resulting in a decrease in the hardness of the coating and an increase in wear.

[0154] Comparative Example 2

[0155] The same as Example 1, except that the solid wire open arc surfacing self-shielding alloy powder in this comparative example includes the following components, calculated by mass percentage: C 28%, B 3.6%, Si 1.3%, Mn 4.7%, Al 4.0%, Cr 0.7%, Ti 2.8%, CaF 0.75% and rare earth elements 0.05%, with the balance being Fe.

[0156] The average particle size of the cored wire open arc surfacing self-shielding alloy powder prepared in this comparative example is 60 to 70 μm.

[0157] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0158] The results show that the hardness of the overlay layer after overlay welding in this comparative example is 50HRC, and the weight loss of the overlay layer is 9mg. The reason is that changing the amount of each element beyond the scope of protection of the patent can cause problems in the coating's formation. Element C is a gas-forming component, and elements such as Al, Mn, and Si are slag-forming components. Changing the amount of each element beyond the scope of protection required by the patent can cause problems such as sand holes, slag inclusions, and pores, resulting in a significant decrease in the coating's hardness and an increase in wear.

[0159] Comparative Example 3

[0160] The same as Example 1, the only difference is that the average particle size of the core wire open arc surfacing self-shielding alloy powder in this comparative example is 100-120 μm, that is, the solid wire open arc surfacing self-shielding alloy powder with an average particle size of 90-100 μm is obtained by sieving.

[0161] The average particle size of the cored wire open arc surfacing self-shielding alloy powder prepared in this comparative example is 90 to 100 μm.

[0162] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0163] The results show that the hardness of the overlay layer after overlay welding in this comparative example is 48HRC, and the weight loss of the overlay layer is 10.5mg. This is because the excessively fine powder particle size causes a large amount of powder splashing during the arc overlay welding process due to the blowing force of the arc, resulting in less elemental components in the powder entering the overlay layer, which in turn reduces the hardness of the overlay layer and increases the weight loss of the overlay layer.

[0164] Comparative Example 4

[0165] The same as Example 1, except that in step 4, the atomizing medium is argon gas at -10°C and the atomizing pressure is 4 MPa.

[0166] The average particle size of the cored wire open arc surfacing self-shielding alloy powder prepared in this comparative example is 20 to 30 μm.

[0167] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0168] The results showed that the hardness of the overlay layer after overlay welding in this comparative example was 44HRC, and the weight loss of the overlay layer was 13mg. The reason for this is that the lack of nitrogen inflow resulted in overly large and uneven particles. After screening, only alloy powder particles with a particle size of 20-30μm were obtained. The overly coarse powder particles did not completely melt the powder particles during the overlay welding process, resulting in few elements in the powder being transferred to the coating, causing a decrease in hardness and increased wear.

[0169] Comparative Example 5

[0170] The same as Example 1, except that in step 4, the atomizing medium is an inert gas at -10°C (composed of argon and nitrogen in a volume ratio of 12:1.2), and the atomizing pressure is 6 MPa.

[0171] The average particle size of the cored wire open arc surfacing self-shielding alloy powder prepared in this comparative example is 60 to 70 μm.

[0172] In order to verify the performance of the prepared cored wire open arc surfacing self-shielding alloy powder, solid wire surfacing was performed using Mn13# steel as a substrate, and the process steps were the same as in Example 1.

[0173] The results show that the hardness of the overlay layer after overlay welding in this comparative example is 40HRC, and the weight loss of the overlay layer is 17.2mg. This is because argon can react with gases such as oxygen on the surface of the metal powder to form a protective layer, preventing the metal powder from reacting with oxygen in the air, thereby ensuring the purity and quality of the metal powder. Changing the proportion of argon gas will result in the metal powder not being fully protected and oxidizing, which in turn affects the formation of the coating during the wire overlay welding process, resulting in the formation of a large number of pores, reducing the hardness of the coating, and increasing wear.

[0174] The cross-sectional view of the coating of the welding wire gas shielded cladding in Example 1 is shown in FIG. Figure 6 The cross-sectional view of the coating after open arc surfacing welding of the self-shielding alloy powder prepared in Example 1 is shown in FIG. Figure 7 In the cross-sectional area of ​​the cladding, the percentage of the metal area melted into the base material and the cross-sectional area of ​​the cladding coating is the dilution rate. Figure 6 、 Figure 7It can be seen that the area of ​​the cladding coating integrated into the base material is larger in the cross-sectional view of the coating after gas shielded cladding with welding wire, while the area of ​​the cladding coating integrated into the base material is smaller in the cross-sectional view of the coating after open arc cladding with self-shielded alloy powder with solid wire. Comparing the two, the addition of powder visible to the naked eye can effectively disperse the heat of the welding wire and reduce the dilution rate.

[0175] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A self-shielding alloy powder for solid wire open arc surfacing, characterized in that: Calculated by mass percentage, it includes the following components: C 11.0% to 15.8%, B 1.0% to 2.0%, Si 1.0% to 2.0%, Mn 1.5% to 2.8%, Al 2.0% to 4.0%, Cr 18.0% to 24.0%, Ti 7.2% to 8.5%, CaF 3% to 4% and rare earth elements 0.08% to 0.4%, the balance is Fe; The average particle size of the solid wire open arc surfacing self-shielding alloy powder is 60 to 90 μm; The method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding comprises the following steps: Mn13# steel is mixed with MnO and Cr3C2 and heated at high temperature for reaction desulfurization and dephosphorization, and after cooling, a main raw material is obtained, B, Al, Ti, Si, CaF and rare earth elements are added to the main raw material according to mass percentage, and mixed and smelted, and then the solid welding wire open arc surfacing self-shielding alloy powder is obtained by atomization granulation and drying; The medium of the atomization granulation is an inert gas at a temperature of -20°C to -10°C, and the pressure of the atomization granulation is 3.8 to 4.2 MPa.

2. The self-shielding alloy powder for solid wire open arc surfacing according to claim 1, characterized in that: Calculated by mass percentage, it includes the following components: C 12.0% to 12.5%, B 1.2% to 1.5%, Si 1.2% to 1.4%, Mn 1.9% to 2.2%, Al 2.2% to 2.8%, Cr 19.0% to 19.5%, Ti 7.5% to 8.0%, CaF 3.8% to 4.0% and rare earth elements 0.1% to 0.15%, and the balance is Fe.

3. The self-shielding alloy powder for solid wire open arc surfacing according to claim 2, characterized in that: Calculated by mass percentage, it includes the following components: C 12.3%, B 1.4%, Si 1.3%, Mn 2.0%, Al 2.5%, Cr 19.0%, Ti 7.6%, CaF 3.9% and rare earth elements 0.12%, and the balance is Fe.

4. The self-shielding alloy powder for solid wire open arc surfacing according to claim 3, characterized in that: The rare earth element is at least one of La, Ce, and Y.

5. A method for preparing the self-shielding alloy powder for solid wire open arc surfacing welding according to any one of claims 1 to 4, characterized in that: The following steps are involved: Mn13# steel is mixed with MnO and Cr3C2 and heated at high temperature for reaction desulfurization and dephosphorization, and after cooling, a main raw material is obtained, B, Al, Ti, Si, CaF and rare earth elements are added to the main raw material according to mass percentage, and mixed and smelted, and then the solid welding wire open arc surfacing self-shielding alloy powder is obtained by atomization granulation and drying; The medium of the atomization granulation is an inert gas at a temperature of -20°C to -10°C, and the pressure of the atomization granulation is 3.8 to 4.2 MPa.

6. The method for preparing self-shielding alloy powder for solid wire open arc surfacing according to claim 5, characterized in that: The temperature of the mixed smelting is 3600-3900° C., and the holding time is 10-11 hours.

7. The method for preparing self-shielding alloy powder for solid wire open arc surfacing according to claim 5, characterized in that: The inert gas is composed of argon and nitrogen in a volume ratio of (9-10):0.

6.

8. Use of the self-shielding alloy powder for open arc surfacing welding of solid welding wire as claimed in any one of claims 1 to 4 in surfacing welding of Mn13# steel solid welding wire.

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