Impact-resistant crack-free high-wear-resistant powder cored wire capable of realizing large-thickness cladding

Abstract

The invention relates to an impact-resistant crack-free high-wear-resistant powder cored wire capable of realizing large-thickness cladding. The welding wire is formed by wrapping alloy powder with a stainless steel strip and comprises the following chemical components in percentage by weight: 1%-3% of manganese, 1%-3% of nickel, 1%-3% of nickel and the balance of iron 10%-18% of chromium; 0.1%-1% of molybdenum; 1%-3% of silicon; 1.5%-3% of carbon; 5%-10% of niobium; 0.1%-1% of tungsten; and the balance of iron and trace unavoidable impurities. When the welding wire provided by the invention is used for welding, a formed coating has no obvious cracks on the surface, can form good metallurgical bonding with a matrix, can tolerate violent impact load, is not easy to peel off, has a uniform, compact, flat and smooth surface, has good wear resistance, and can realize large-size and large-thickness cladding repair.

Description

Technical Field

[0001] The present invention belongs to the technical fields of materials science and welding materials, and particularly relates to a high wear-resistant flux-cored wire with impact resistance and crack-free property for large-thickness cladding. Background Art

[0002] In heavy industries such as mining machinery, metallurgical rolls, and construction machinery, key components such as crusher tooth plates, excavator bucket teeth, and conveyor roller paths are long-term subjected to the combined action of heavy load impact, high-speed abrasive wear, and high-frequency alternating loads. The surface is prone to plowing wear, peeling, and stress cracks, which severely restrict production efficiency and the service life of equipment. Currently, the main solution to this problem is to use wear-resistant materials to strengthen and repair the working surface of workpieces. These materials often have high hardness and good wear resistance, but during the cladding repair process, carbides will continuously precipitate along the grain boundaries, resulting in a large number of cracks in the surface wear-resistant layer. At the same time, there will be large stresses at the interface bonding, which are prone to problems such as peeling under strong impact loads, and it is impossible to achieve large-size and large-thickness cladding repair because the increase in cladding thickness will cause more cracks and greater residual stresses in the cladding layer. And materials with good plasticity have low hardness and poor wear resistance. Although they can be used for repair manufacturing, they far cannot meet the wear resistance requirements of key components in construction machinery. Therefore, it is urgent to develop a new type of material that combines high wear resistance, strong impact resistance, no cracks during manufacturing, and can achieve large-thickness cladding repair, breaking through the technical bottleneck of traditional materials in the field of construction machinery equipment manufacturing and repair. Summary of the Invention

[0003] The purpose of the present invention is to provide a high wear-resistant flux-cored wire with impact resistance and crack-free property for large-thickness cladding, aiming to overcome the above-mentioned disadvantages of the prior art and improve or solve the above problems.

[0004] To achieve the above purpose, the technical solution of the present invention is as follows:

[0005] A high wear-resistant flux-cored wire with impact resistance and crack-free property for large-thickness cladding, characterized in that the wire comprises a steel strip outer skin and alloy powder, and the alloy powder is filled in the steel strip outer skin. The chemical composition of the wire by weight percentage is: manganese: 1% - 3%; chromium: 10% - 18%; molybdenum: 0.1% - 1%; silicon: 1% - 3%; carbon: 1.5% - 3%; niobium: 5% - 10%; tungsten: 0.1% - 1%; the balance is iron and trace inevitable impurities.

[0006] Further, in the high wear-resistant flux-cored wire with impact resistance and crack-free property for large-thickness cladding, the powder core alloy powder accounts for 18 - 30% of the weight of the wire, and the skin is a 430 cold-rolled stainless steel strip.

[0007] Further, the alloy powder has the following characteristics:

[0008] (1) The alloy powder contains at least one of ferromanganese, electrolytic manganese metal, and ferrosilicon manganese;

[0009] (2) The alloy powder contains at least one of metal chromium powder, high-carbon ferrochrome, medium-carbon ferrochrome, and micro-carbon ferrochrome;

[0010] (3) The alloy powder contains at least one of ferrosilicon, ferroboron, titanium boron alloy, ferromolybdenum, and ferrotungsten;

[0011] (4) The particle size of each raw material in the alloy powder is 60 - 100 mesh.

[0012] Furthermore, the diameter of the flux-cored wire is 1.2 - 1.6 mm.

[0013] Furthermore, a method for preparing a kind of impact-resistant, crack-free, and highly wear-resistant flux-cored wire capable of large-thickness cladding is as follows: The wire is made by rolling a carbon steel strip into a U shape, uniformly mixing the flux-cored alloy powder and putting it into the U-shaped groove, then rolling it into a semi-finished wire with a diameter of 3.5 - 5 mm, and finally obtaining the wire through drawing.

[0014] Furthermore, this flux-cored wire can achieve the cladding repair of large-size thickness, and the thickness of the prepared cladding layer can reach 5 mm - 30 mm.

[0015] Furthermore, the cladding repair layer has good wear resistance, while optimizing the construction process performance of the wire, reducing spatter and fume during the cladding process, and no cracks are generated in the cladding layer. It is applied to the manufacturing and repair of mining machinery and construction machinery in the fields of heavy load impact and severe wear.

[0016] Compared with the prior art, the present invention has the following positive and progressive beneficial effects:

[0017] (1) For the impact-resistant, crack-free, and highly wear-resistant flux-cored wire capable of large-thickness cladding of the present invention, only a low carbon content exists in the cladding layer, which can inhibit the generation of a large number of coarse carbides in the structure, reduce the precipitation of carbides at the grain boundaries, and thus reduce the generation of cracks; in addition, alloy powders such as ferroniobium are added, and a large number of uniformly distributed hard phases are formed in the structure. The uniformly distributed hard phases can reduce stress concentration and prevent the generation of cracks;

[0018] (2) For the impact-resistant, crack-free, and highly wear-resistant flux-cored wire capable of large-thickness cladding of the present invention, the formula of the flux-cored alloy is optimized, good process performance is obtained, spatter and fume during the cladding process are reduced, a metallurgical bond is formed between the cladding layer and the base layer, the stress generated during the cladding repair process is reduced, the cladding layer is not easily peeled off, it can withstand severe impact loads, and multi-layer cladding repair can be carried out to obtain a thick wear-resistant layer;

[0019] (3) The flux cored wire with high wear resistance, impact resistance and crack resistance for large thickness cladding according to the present invention contains a large amount of hard phases formed by wear-resistant elements such as manganese, chromium, molybdenum, niobium, silicon, carbon, tungsten, etc. in the cladding layer prepared. The hard phases are uniformly distributed in the structure. A large amount of eutectic structure and composite carbide ((Nb,Mo)3C) exist in the structure, which can form a good wear-resistant layer, greatly improving the ability of the cladding layer to resist external wear. The lamellar structure in the eutectic structure can also improve toughness and impact resistance, and the comprehensive performance of the cladding layer is good. Brief Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art.

[0021] Figure 1 It is the surface macroscopic morphology diagram of the surfacing layers prepared in Examples 1 and 2 and Comparative Examples 1 and 2 of the present application. Detailed Embodiments

[0022] The following Figure 1 illustrates the embodiments of the present invention through the following and specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. It should also be understood that the terms used in the embodiments of the present invention are for the purpose of describing specific specific implementation manners, rather than for limiting the protection scope of the present invention. The test methods without specific conditions noted in the following embodiments are usually in accordance with conventional conditions or in accordance with the conditions recommended by each manufacturer.

[0023] When the embodiments give a numerical range, it should be understood that, unless otherwise specified in the present invention, any value between the two endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention, based on the understanding of those skilled in the art of the prior art and the description of the present invention, can also use any methods, devices and materials similar or equivalent to the methods, devices and materials described in the embodiments of the present invention to implement the present invention.

[0024] Experiment:

[0025] The coating was prepared using the following cladding process parameters: the cladding current was 280 - 300 A, the cladding voltage was 27 - 30 V, the feed rate was 260 mm / min, the lap spacing was 7 - 8 mm, the weld length was 160 mm, the shielding gas was a flux-cored mixed gas with a volume fraction of (78 - 80% Ar + 22 - 20% CO₂), the shielding gas flow rate was 15 L / min. The coating was prepared by means of flux-cored gas shielded welding on the substrate. It should be noted that after each weld pass, sufficient heat dissipation should be ensured before lapping the next pass to prevent excessive deformation and deterioration of the forming performance caused by continuous heat input.

[0026] For the wear test, alumina balls with a diameter of φ6 mm were used as the counter balls. The test was carried out on an MMW-1A vertical universal friction and wear testing machine under the conditions of a load of 200 N, a rotation radius of 4.5 mm, and a speed of 50 r / min for 30 min. The weight differences of 3 specimens before and after the test were recorded. The wear resistance of the Q345 substrate under laboratory conditions was defined as 1, and the wear ratio of the cladding layer with different carbon contents was obtained by dividing the cross-sectional area of the substrate wear scar by the cross-sectional area of the wear scar of the specimens with different carbon contents.

[0027] Example 1

[0028] The chemical composition of the welding wire by weight percentage was: C: 1.5%, Si: 1.5%, Mn: 2.5%, Cr: 12.77%, Nb: 6%, Mo: 0.5%, W: 0.6%, Ni: 0.56%, Fe: 74.07%; 430 cold-rolled stainless steel strip was used as the outer skin of the welding wire; the diameter of the welding wire was 1.6 mm; the proportion of the powder core in the total weight of the welding wire was 27%; the steel strip was rolled into a U-shaped groove, the powder was mixed and dried and then added, and the welding wire was obtained through rolling and wire drawing for diameter reduction.

[0029] The coating prepared with the welding wire of Example 1 had good formability, less spatter, beautiful appearance, no cracks on the surface, and formed a good metallurgical bond with the substrate, and could withstand strong impact loads; the wear resistance of the cladding layer was 13.2 times that of the Q345 substrate, showing good wear resistance and enabling large-thickness cladding repair.

[0030] Example 2

[0031] The chemical composition of the welding wire by weight percentage was: C: 2.5%, Si: 1.5%, Mn: 2.5%, Cr: 12.77%, Nb: 6%, Mo: 0.5%, W: 0.6%, Ni: 0.56%, Fe: 73.07%; 430 cold-rolled stainless steel strip was used as the outer skin of the welding wire; the diameter of the welding wire was 1.6 mm; the proportion of the powder core in the total weight of the welding wire was 27%; the steel strip was rolled into a U-shaped groove, the powder was mixed and dried and then added, and the welding wire was obtained through rolling and wire drawing for diameter reduction.

[0032] The coating prepared from the welding wire of Example 2 has good formability, less spatter, beautiful forming, no cracks on the surface, forms a good metallurgical bond with the substrate, and can withstand strong impact loads; the wear resistance of the cladding layer is 13.8 times that of the Q345 substrate, showing good wear resistance and enabling large-thickness cladding repair.

[0033] Example 3

[0034] The chemical composition of the welding wire by weight percentage is: C: 2.5%, Si: 1.5%, Mn: 2.5%, Cr: 12.77%, Nb: 8%, Mo: 0.5%, W: 0.6%, Ni: 0.56%, Fe: 71.07%; 430 cold-rolled stainless steel strip is used as the outer skin of the welding wire; the diameter of the welding wire is 1.6 mm; the proportion of the powder core of the welding wire in the total weight of the welding wire is 27%; the steel strip is rolled into a U-shaped groove, the powder is mixed and dried and then added, and the welding wire is obtained through rolling and wire drawing for diameter reduction.

[0035] The coating prepared from the welding wire of Example 3 has good formability, less spatter, beautiful forming, no cracks on the surface, forms a good metallurgical bond with the substrate, and can withstand strong impact loads; the wear resistance of the cladding layer is 17.7 times that of the Q345 substrate, showing good wear resistance and enabling large-thickness cladding repair.

[0036] Comparative Example 1

[0037] The chemical composition of the welding wire by weight percentage is: C: 5%, Si: 1.8%, Mn: 0.8%, Cr: 13%, Nb: 6%, Mo: 0.5%, W: 0.6%, Ni: 0.56%, Fe: 68.74%; 430 cold-rolled stainless steel strip is used as the outer skin of the welding wire; the diameter of the welding wire is 1.6 mm; the proportion of the powder core of the welding wire in the total weight of the welding wire is 27%; the steel strip is rolled into a U-shaped groove, the powder is mixed and dried and then added, and the welding wire is obtained through rolling and wire drawing for diameter reduction.

[0038] The coating prepared from the welding wire of Comparative Example 1 has relatively good wear resistance, but poor formability, more spatter, a large number of cracks and pores on the surface, low bonding strength with the substrate, not resistant to impact, and unable to achieve large-thickness cladding repair.

[0039] Comparative Example 2

[0040] The chemical composition of the welding wire is by weight percentage: C: 2.5%, Si: 1.5%, Mn: 2.5%, Cr: 12.77%, Nb: 4%, Mo: 0.5%, W: 0.6%, Ni: 0.56%, Fe: 70.57%; 430 cold-rolled stainless steel strip is used as the outer skin of the welding wire; the diameter of the welding wire is 1.6 mm; the proportion of the powder core of the welding wire in the total weight of the welding wire is 27%; the steel strip is rolled into a U-shaped groove, the powder is mixed and dried and then added, and the welding wire is obtained through rolling and wire drawing for diameter reduction.

[0041] The coating formability of the welding wire of Comparative Example 2 is good, and there are no pores and cracks on the surface of the cladding layer, but the wear resistance is significantly reduced compared with that of Example 2.

[0042] Comparative Example 3

[0043] The chemical composition of the welding wire is by weight percentage: C: 1.5%, Mn: 0.8%, Cr: 4%, Nb: 6%, Mo: 0.5%, W: 0.6%, Ni: 0.56%, Fe: 65.34%; 430 cold-rolled stainless steel strip is used as the outer skin of the welding wire; the diameter of the welding wire is 1.6 mm; the proportion of the powder core of the welding wire in the total weight of the welding wire is 27%; the steel strip is rolled into a U-shaped groove, the powder is mixed and dried and then added, and the welding wire is obtained through rolling and wire drawing for diameter reduction.

[0044] The coating formability of the welding wire of Comparative Example 3 is poor, there is a lot of spatter, the surface oxidation is serious, there is no luster, there are cracks in the cladding layer, and the wear resistance is significantly reduced compared with that of Example 3.

Claims

1. A high wear-resistant flux-cored wire with impact resistance and no cracks that can be clad with a large thickness, characterized in that, The welding wire includes a steel strip outer skin and alloy powder, and the alloy powder is filled in the steel strip outer skin. The chemical composition of the welding wire, by weight percentage, is as follows: manganese: 1% - 3%; chromium: 10% - 18%; molybdenum: 0.1% - 1%; silicon: 1% - 3%; carbon: 1.5% - 3%; niobium: 5% - 10%; tungsten: 0.1% - 1%; the balance is iron and trace inevitable impurities.

2. The high wear-resistant flux-cored wire with impact resistance and no crack for large-thickness cladding according to claim 1, wherein The alloy powder of the welding wire accounts for 18% - 30% of the weight of the welding wire, and the wire skin is a 430 cold-rolled stainless steel strip.

3. The flux-cored wire for high wear resistance with impact resistance and no crack, which can be clad with large thickness according to claim 1, is characterized in that, The alloy powder has the following characteristics: (1) The alloy powder contains at least one of ferromanganese, electrolytic manganese metal, and ferrosilicon manganese; (2) The alloy powder contains at least one of metal chromium powder, high-carbon ferrochrome, medium-carbon ferrochrome, and micro-carbon ferrochrome; (3) The alloy powder contains at least one of ferrosilicon, ferroboron, titanium boron alloy, ferromolybdenum, and ferrotungsten; (4) The particle size of each raw material in the alloy powder is 60 - 100 mesh.

4. A shock-resistant crack-free high-wear-resistant flux-cored wire capable of large-thickness cladding according to claim 1, characterized in that, The diameter of the welding wire is 1.2 - 1.6 mm.

5. A shock-resistant crack-free high-wear-resistant flux-cored wire capable of large-thickness cladding according to claim 1, characterized in that The welding wire is obtained by first rolling a 430 stainless steel strip into a U shape, putting the powder core alloy powder of the welding wire into the U-shaped groove after mixing evenly, then rolling it into a semi-finished welding wire with a diameter of 3.5 - 5 mm, and finally obtaining it through drawing.

6. A high wear-resistant flux-cored wire with impact resistance and no cracks that can be clad with a large thickness, as claimed in claim 1, wherein This flux-cored wire can achieve the cladding repair of large-size thickness, and the thickness of the prepared cladding layer can reach 5 mm - 30 mm.

7. A high wear-resistant flux-cored wire with impact resistance and no cracks that can be clad with a large thickness according to claim 1, characterized in that, The cladding repair layer has good wear resistance, while optimizing the construction process performance of the welding wire, reducing spatter and fume during the cladding process, and no cracks are generated in the cladding layer. It is applied to the manufacturing and repair of mining machinery and construction machinery in the fields of heavy load impact and severe wear.

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