A low cost method of manufacturing a ceramic phase modified h13 solid wire

Abstract

The application is a kind of low-cost preparation method of ceramic phase modified H13 solid core welding wire. The method is to mechanically grind SiO2, MgO, CaO and other nano ceramic phase powders with iron powder, then ball mill the obtained homogenized ceramic phase powder to obtain a ceramic phase toughening agent; continue to add sodium water glass binder, roll into spherical material, finally according to the raw material ratio of H13 steel, add the required raw materials of elements into the smelting furnace, at the same time add the spherical material, through forging, rolling, cold drawing, the welding wire is obtained. The application solves the problems of small specific gravity of nano ceramic phase powder in molten steel, easy to float, poor wettability, small particle size and easy to agglomerate, improves the drawing performance of H13 steel, and forms a kind of H13 solid core welding wire preparation method with simple process.

Description

Technical Field

[0001] This invention relates to the field of welding materials technology, specifically to a low-cost method for preparing H13 solid welding wire with high hardness. Background Technology

[0002] H13 (4Cr5MoSiV1) steel is a hot work die steel. Due to the harsh working conditions, die steels require high performance characteristics, including good strength (hardness, red hardness, compressive yield strength), toughness, wear resistance, fatigue resistance, and anti-galling properties. These performance requirements typically result in higher prices for die steels. To save costs, many dies and rolls using die steel employ a composite welding method, where the core uses inexpensive ordinary steel, while the outer working layer is welded using die steel welding wire.

[0003] Because mold steel has medium to high carbon content and high alloy content, its hardness is generally high, and its cold-drawing performance is poor, making it difficult to manufacture solid welding wire. Therefore, the welding wire used for surfacing is primarily flux-cored welding wire. Flux-cored welding wire is made by winding alloy powder into steel strip in a certain proportion and then drawing and reducing its diameter. This manufacturing method easily leads to compositional inhomogeneity during the subsequent surfacing process, resulting in inhomogeneity in performance. In many high-performance applications, this inhomogeneity often makes it difficult to meet the requirements, forcing the abandonment of composite manufacturing solutions and the use of integral mold steel, thus increasing production costs.

[0004] Therefore, domestic and international research on manufacturing cold-drawn solid welding wire for mold steel has been limited to attempts to remove excessive cold-drawing resistance through multiple tempering processes. However, this method cannot improve the toughness and ductility of the wire, nor can it solve the problem of frequent wire breakage. The high carbon and alloy content of mold steel, and the resulting high hardness and low toughness, pose obstacles to manufacturing solid welding wire from mold steel.

[0005] In the smelting process of mold steel, the addition of ceramic phases such as SiO2, MgO, and CaO to molten steel to achieve toughening and improve its cold drawing performance when used to make welding wire is the core of this invention. However, ceramic phases have high melting points, lower density compared to molten steel, and are prone to floating. Furthermore, their poor wettability with molten steel makes it difficult to effectively incorporate oxide powders into the steel. If these ceramic phases are nano-sized ultrafine particles, they are also prone to agglomeration. Therefore, existing smelting processes make it difficult to directly and uniformly disperse ultrafine ceramic phase particles into molten steel.

[0006] Patents CN 111254343 B, CN 111235467 B, and CN 114637103 A address the issues of oxide and mineral powder floating and non-wetting. They describe mixing two or more of the following (containing 2%–90% of each oxide): corundum powder, bauxite, silica powder, boron oxide, alumina, yttrium oxide, titanium oxide, and zirconium oxide, with iron powder or iron-based alloy powder. This mixture is then sintered or smelted to form an intermediate alloy, which is added in a specific proportion to a steelmaking furnace to produce oxide dispersion-strengthened steel. The preparation of this intermediate alloy requires sintering and smelting, and even vacuum discharge processing, making the process cumbersome. Summary of the Invention

[0007] This invention addresses the problem that H13 die steel cannot be drawn into solid welding wire by providing a low-cost method for preparing H13 solid welding wire modified with ceramic phase. This method solves the problems of low specific gravity, easy floating, poor wettability, and easy agglomeration of nano-ceramic phase powders in molten steel by mechanically alloying SiO2, MgO, CaO, and other nano-ceramic phase powders with iron powder. When added to molten steel, these nano-ceramic phase powders act as heterogeneous nucleation cores, providing fine-grain strengthening, and as fine secondary phases, providing dispersion strengthening, thereby improving the material's toughness and ductility. This results in a simple process for preparing H13 solid welding wire.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows:

[0009] A low-cost method for preparing ceramic phase-modified H13 solid welding wire, the method comprising the following steps:

[0010] 1) Add the ceramic phase material to a ball mill and ball mill for 3-5 hours to obtain ceramic phase powder;

[0011] The ceramic phase material is one or more of SiO2, MgO and CaO;

[0012] The particle size range of the ceramic phase powder is 50–100 nm;

[0013] 2) The ceramic phase powder and the iron-based powder are loaded into a V-type mixer and homogenized for 1 to 5 hours to obtain homogenized ceramic phase powder; wherein the mass ratio of homogenized ceramic phase powder to iron-based powder is (2-3):(15-20).

[0014] 3) The homogenized ceramic phase powder is put back into the ball mill for mechanical alloying for 8-15 hours to obtain the ceramic phase toughening agent;

[0015] 4) Place the ceramic phase toughening agent in a drum, add sodium silicate binder, roll it into spherical material, and then dry it at 140-180℃ for 10-60 minutes to obtain spherical ceramic phase toughening agent particles with a diameter of 0.4-1mm.

[0016] The amount of sodium silicate binder added is 13-17% of the total weight of the ceramic phase toughening agent, and the diameter of the spherical ceramic phase toughening agent particles is preferably 0.5-0.8 mm.

[0017] 5) According to the raw material ratio of H13 steel, add the raw materials of the required elements into the melting furnace, and add the ceramic phase toughening agent particles from step 4). Then, heat the furnace to 1590-1680℃ at a rate of 8-25℃ / min, hold for 15-20 minutes to complete the preliminary melting, obtain molten steel, and then refine it and cast it into ingots.

[0018] The mass ratio of ceramic phase toughening agent to steel raw material is (10-100):1000;

[0019] 6) Forge the ingot into a square billet, and then hot roll it into wire rod with a diameter of 5.5 to 8.0 mm;

[0020] 7) The obtained wire rod is pickled and then cold-drawn to reduce the diameter to 1.2-4.0 mm. The diameter reduction is 10-30% each time, and finally welding wire is obtained.

[0021] The hardness of the material after surfacing with the above-mentioned welding wire shall not be less than 53 HRC, the hardness after tempering at 550℃ for 2 hours shall not be less than 55 HRC, the tensile strength shall not be less than 1700 MPa, and the V-notch impact toughness shall not be less than 14 J / cm². 2 .

[0022] In step 1), the mass ratio of the ceramic phase powders is SiO2: 0%–100%; MgO: 0%–100%; CaO: 0%–100%, and the ratio of the three is not 0 at the same time.

[0023] The iron-based powder in step 2) is preferably industrial pure iron powder.

[0024] The iron-based powder in step 2) has a particle size of 150μm to 250μm (60 mesh to 100 mesh).

[0025] The smelting furnace in step 5) is a medium-frequency furnace.

[0026] The refining process described in step 5) is electroslag remelting or LF (ladle refining furnace) + VD (vacuum degassing furnace).

[0027] Step 7) also includes annealing, specifically continuous hydrogen annealing at a temperature of 600℃~750℃ and a wire running speed of 1~4m / min.

[0028] The beneficial effects of this invention are as follows:

[0029] Compared to the current situation where H13 die steel cannot be drawn into solid welding wire, this invention uses mechanical alloying to add ceramic phases (SiO2, melting point 1650℃; MgO, melting point 2800℃; CaO, 2572℃), which are usually considered inclusions, into the H13 steel without changing the conventional smelting method. These added ceramic phase particles are evenly dispersed in the molten steel in a fine dispersion manner, which improves the toughness and ductility of H13, allowing it to be cold-drawn into solid welding wire through normal drawing methods.

[0030] First, the selection criteria for these ceramic phases are as follows: firstly, they must have a sufficiently high melting point to ensure that they remain solid at the highest temperature during the steelmaking process; secondly, the surface energy difference between them and steel should be as small as possible; and thirdly, their particle size should be on the nanometer scale.

[0031] Secondly, mechanical alloying solved the problems of stable suspension, high dispersion, and mutual wetting between the nano-ceramic phase and molten steel. High-energy, long-term ball milling mechanical alloying embeds the hard ceramic phase into specially selected soft industrial pure iron particles, ensuring that the ceramic phase does not float to the surface and form slag during steelmaking, while also ensuring the wetting of the ceramic phase with the molten steel and its effective dispersion in the molten steel.

[0032] Third, during the solidification process of molten steel, the nanoscale ceramic phase acts as a heterogeneous nucleation core, increasing the number of nuclei formed during solidification and significantly refining the steel's microstructure, resulting in fine-grain strengthening. Simultaneously, the fine, dispersed, and uniformly distributed ceramic phase particles in the steel matrix contribute to dispersion strengthening.

[0033] Fourth, through the selection and optimization of the types and proportions of the ceramic phases, the steel is not only easy to draw into solid welding wires with good weld overlay properties, but also, after tempering at 550℃ for 2 hours, the welded material exhibits a tensile strength of not less than 1700 MPa and a V-notch impact toughness of not less than 14 J / cm². 2 Under the premise that the hardness is not less than 55HRC, the above mechanical property indicators are the best values ​​of H13 steel weld overlay performance that have been searched and reported to date. This indicates that the material welded using this solid welding wire has good wear resistance under the conditions of high strength and good toughness.

[0034] Fifth, electroslag remelting or multiple remelting of steel does not affect the dispersion strengthening effect of oxides on steel.

[0035] Sixth, it does not require changes to existing H13 steel production equipment and is suitable for the preparation of high-performance steel. Attached image description:

[0036] Figure 1 Electron microscopy images and energy dispersive spectroscopy (EDS) analysis results of the wire rod extraction product in Example 1, wherein, Figure 1 (a) shows the morphology of the extract. Figure 1 (b) shows the results of energy dispersive spectroscopy analysis of the particles in the box region of (a);

[0037] Figure 2 The distribution of oxide particles in the wire rod in Example 8 as observed under a transmission electron microscope, and the results of energy dispersive spectroscopy analysis of particle A. Detailed Implementation

[0038] Example 1—4Cr5MoSiV1(H13) steel

[0039] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 3 hours to a particle size of 50-80 nm. Then, 11 kg of the ground oxide and 55 kg of iron powder with a particle size of 150 μm were placed together in a V-type mixer and thoroughly mixed for 3 hours. The mixture was then further mechanically alloyed in a ball mill for 10 hours to prepare the ceramic phase toughening agent. Subsequently, 13.5% (by mass percentage of sodium silicate) of sodium silicate was added to the ceramic phase toughening agent, and the mixture was rolled into spherical materials with a diameter of 0.6-1.0 mm and dried. The drying temperature was 140℃, and the drying time was 60 min. Then, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (30 steel, ferrochrome, ferrosilicon, ferromolybdenum, ferrovanadium, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the ratio of spherical materials to smelting raw materials was 1:20. The heating rate during the smelting process is controlled at 10℃ / min. The raw material is heated to 1590℃ and completely melted into molten steel. This is held for 15 minutes, then refined using LF and degassed using VD in a 10-ton ladle for 45 minutes before being cast into steel ingots. The ingots are then forged into square billets and further rolled into Φ6mm wire rods. These wire rods are pickled and then cold-drawn in six passes to reduce their diameter to 1.6mm, with a minimum reduction of 15% per pass. Every three cold-drawing passes are followed by continuous hydrogen annealing at 600℃ and a speed of 1m / min.

[0040] Figure 1 This is the result of electron microscopy observation and corresponding energy dispersive spectroscopy analysis of oxide particles extracted from wire rods. Due to their small size, the particles easily aggregate. However... Figure 1 (a) clearly shows that the size of most of these oxides does not exceed 100 nm, and they are composed of CaO, MgO, and SiO2 particles. This indicates that the ceramic phase toughening agent prepared by mechanical alloying was uniformly dispersed into the produced steel after being added to the molten steel, and no agglomeration was observed.

[0041] Figure 1 The energy dispersive spectroscopy results in (b) demonstrate that the chemical composition of the extracted product consists of Ca, Mg, Si and O elements, indirectly proving that these oxide particles are CaO, MgO and SiO2.

[0042] The material prepared by surfacing with drawn welding wire under a protective atmosphere of 98% argon and 2% carbon dioxide, after tempering at 550℃ for 1.5h, has a tensile strength of 1720MPa and a V-notch impact toughness of 14.8J / cm. 2 The hardness is 55.5 HRC. This fully demonstrates that these dispersed nano-oxide particles can not only act as heterogeneous nucleation points during the solidification and phase transformation of steel, refining the microstructure and improving the strength and toughness of the material, but also effectively improve its weldability.

[0043] In the performance tests of this invention embodiment, the hardness test was performed using an HR-150A Rockwell hardness tester, the tensile strength was measured using a Shimadzu AGS-X-50KN tensile testing machine, and the impact toughness was tested using a 10mm×10mm×55mm V-notch standard test block on a Sansi PTM 2200 impact testing machine.

[0044] Example 2—4Cr5MoSiV1(H13) steel

[0045] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 5 hours to a particle size of 75–100 nm. Then, 12 kg of the ground oxide from Table 1 and 72 kg of iron powder with a particle size of 165 μm were placed together in a V-type mixer and thoroughly mixed for 1 hour. The mixture was then further mechanically alloyed in a ball mill for 15 hours to prepare a ceramic phase toughening agent. Afterward, 15% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.5–0.8 mm, which were then dried. The drying temperature was 155℃, and the drying time was 45 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (25 steel, ferrochrome, ferrosilicon, ferromolybdenum, vanadium-nitrogen alloy, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:33. The heating rate during the smelting process is controlled at 13℃ / min. The raw material is heated to 1620℃ and completely melted into molten steel. This is held at that temperature for 18 minutes, then refined using LF and degassed using VD in a 20-ton ladle for 60 minutes before being cast into steel ingots. The ingots are then forged into square billets, which are further rolled into Φ8mm wire rods. These wire rods are pickled and then cold-drawn in five passes to reduce their diameter to 2.0mm, with a minimum reduction of 18% per pass. Every three cold-drawing passes are followed by continuous hydrogen annealing at 630℃ and a speed of 1.5m / min.

[0046] Example 3—4Cr5MoSiV1(H13) steel

[0047] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 4 hours to a particle size of 60-90 nm. Then, 15 kg of the ground oxide from Table 1 and 130 kg of iron powder with a particle size of 192 μm were placed together in a V-type mixer and thoroughly mixed for 5 hours. The mixture was then further mechanically alloyed in a ball mill for 8 hours to prepare a ceramic phase toughening agent. Afterward, 16.3% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.6-1.0 mm, which were then dried. The drying temperature was 162℃, and the drying time was 53 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (20 steel, ferrochrome, ferrosilicon, ferromolybdenum, ferrovanadium, and ferromanganese) to smelt into steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:67. The heating rate during the smelting process was controlled at 18℃ / min. The raw materials were heated to 1660℃ and completely melted into molten steel. This was held for 19 minutes, followed by LF refining and VD degassing treatment for 50 minutes in a 10-ton ladle, and then cast into steel ingots. The ingots were then forged into square billets and further rolled into Φ7.2mm wire rods. These wire rods underwent pickling and were then cold-drawn in four passes to reduce their diameter to 3.2mm, with a minimum reduction of 18% per pass. After every two cold-drawing passes, a continuous hydrogen annealing treatment was performed at 690℃ and a speed of 2.3m / min. The drawn welding wire was then submerged arc welded under the protection of TLF601 sintered flux. The resulting material, after tempering at 550℃ for 1.5 hours, exhibited a tensile strength of 1710MPa and a V-notch impact toughness of 16.5J / cm². 2 Its hardness is 56 HRC.

[0048] Example 4—4Cr5MoSiV1(H13) steel

[0049] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 5 hours to a particle size of 50–90 nm. Then, 24.8 kg of the ground oxide from Table 1 and 124 kg of iron powder with a particle size of 212 μm were placed together in a V-type mixer and thoroughly mixed for 2 hours. The mixture was then further mechanically alloyed in a ball mill for 12 hours to prepare a ceramic phase toughening agent. Afterward, 17% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.4–0.75 mm, which were then dried. The drying temperature was 180℃, and the drying time was 10 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (industrial pure iron, ferrochrome, ferrosilicon, ferromolybdenum, vanadium-nitrogen alloy, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:15. The heating rate during the smelting process is controlled at 25℃ / min. The raw material is heated to 1680℃ and completely melted into molten steel. This is held at that temperature for 20 minutes, then refined using LF and degassed using VD in a 20-ton ladle for 65 minutes before being cast into steel ingots. The ingots are then forged into square billets, which are further rolled into Φ7.9mm wire rods. These wire rods undergo pickling, followed by a two-pass cold drawing process to reduce their diameter to 4.0mm, with a minimum reduction of 30% per pass. They then undergo a single continuous hydrogen annealing treatment at 730℃ and a rate of 4m / min.

[0050] Example 5—4Cr5MoSiV1(H13) steel

[0051] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 3 hours to a particle size of 50-100 nm. Then, 31 kg of the ground oxide from Table 1 and 257 kg of iron powder with a particle size of 250 μm were placed together in a V-type mixer and thoroughly mixed for 5 hours. The mixture was then further mechanically alloyed in a ball mill for 10 hours to prepare a ceramic phase toughening agent. Afterward, 14.7% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.5-0.9 mm, which were then dried. The drying temperature was 149℃, and the drying time was 34 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (25 steel, ferrochrome, ferrosilicon, ferromolybdenum, vanadium-nitrogen alloy, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:10. The heating rate during the smelting process is controlled at 16℃ / min. The raw material is heated to 1672℃ and completely melted into molten steel. This temperature is maintained for 16 minutes, followed by LF refining and VD degassing treatment in a 10-ton ladle for 40 minutes, before being cast into steel ingots. The ingots are then forged into square billets, which are further rolled into Φ5.5mm wire rods. These wire rods undergo pickling and are then cold-drawn in eight passes to reduce their diameter to 1.2mm, with a minimum reduction of 10% per pass. Every three cold-drawing passes are followed by continuous hydrogen annealing at 660℃ and a speed of 3.3m / min.

[0052] Example 6—4Cr5MoSiV1(H13) steel

[0053] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 4 hours to a particle size of 60–100 nm. Then, 18 kg of the ground oxide from Table 1 and 152 kg of iron powder with a particle size of 173 μm were placed together in a V-type mixer and thoroughly mixed for 2 hours. The mixture was then further mechanically alloyed in a ball mill for 11 hours to prepare a ceramic phase toughening agent. Afterward, 15.6% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.4–0.8 mm, which were then dried. The drying temperature was 171℃, and the drying time was 22 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (Q235 steel, ferrochrome, ferrosilicon, ferromolybdenum, ferrovanadium, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:41. The heating rate during the smelting process is controlled at 21℃ / min. The raw material is heated to 1634℃ and completely melted into molten steel. This is held at that temperature for 17 minutes, then refined using LF and degassed using VD in a 20-ton ladle for 60 minutes before being cast into steel ingots. The ingots are then forged into square billets, which are further rolled into Φ5.9mm wire rods. These wire rods are pickled and then cold-drawn in four passes to reduce their diameter to 2.8mm, with a minimum reduction of 15% per pass. Every two cold-drawing passes are followed by continuous hydrogen annealing at 710℃ and a speed of 2.7m / min.

[0054] Example 7—4Cr5MoSiV1(H13) steel

[0055] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 3 hours to a particle size of 50–90 nm. Then, 8.8 kg of the ground oxide from Table 1 and 88 kg of iron powder with a particle size of 182 μm were placed together in a V-type mixer and thoroughly mixed for 4 hours. The mixture was then further mechanically alloyed in a ball mill for 12 hours to prepare a ceramic phase toughening agent. Afterward, 13.9% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.5–0.7 mm, which were then dried. The drying temperature was 158℃, and the drying time was 29 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (20MnSi steel, ferrochrome, ferrosilicon, ferromolybdenum, ferrovanadium, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:83. The heating rate during the smelting process is controlled at 8℃ / min. The raw material is heated to 1631℃ and completely melted into molten steel. This temperature is maintained for 17 minutes, followed by LF refining and VD degassing treatment in a 10-ton ladle for 40 minutes, before being cast into steel ingots. The ingots are then forged into square billets, which are further rolled into Φ7.6mm wire rods. These wire rods undergo pickling and are then cold-drawn in four passes to reduce their diameter to 2.5mm, with a minimum reduction of 21% per pass. Every two cold-drawing passes are followed by continuous hydrogen annealing at 750℃ and a speed of 1.8m / min.

[0056] Example 8—4Cr5MoSiV1(H13) steel

[0057] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 3 hours to a particle size of 70-100 nm. Then, 7.4 kg of the ground oxide from Table 1 and 74 kg of iron powder with a particle size of 202 μm were placed together in a V-type mixer and thoroughly mixed for 3 hours. The mixture was then further mechanically alloyed in a ball mill for 15 hours to prepare a ceramic phase toughening agent. Afterward, 13% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.6-0.8 mm, which were then dried. The drying temperature was 166℃, and the drying time was 49 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (20CrMnSi steel, ferrochrome, ferrosilicon, ferromolybdenum, ferrovanadium, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:100. The heating rate during the smelting process is controlled at 11℃ / min, heating the raw material to 1655℃ until it is completely melted into molten steel. This is held for 15 minutes, then refined using LF and degassed using VD in a 10-ton ladle for 50 minutes before being cast into steel ingots. The ingots are then forged into square billets, which are further rolled into Φ6.6mm wire rods. These wire rods are pickled and then cold-drawn in five passes to reduce their diameter to 2.0mm, with a minimum reduction of 16% per pass. Every three cold-drawing passes are followed by continuous hydrogen annealing at 643℃ and a rate of 2.9m / min. Figure 2 The distribution of oxide particles observed under a transmission electron microscope (arrows indicate this) shows that their size is less than 100 nm, and the energy dispersive spectroscopy analysis results prove that they are MgO particles. This indicates that the single-component nano-ceramic phase can also be uniformly distributed in the refined steel, and can also be used independently as a heterogeneous nucleation core and a second-phase reinforcing particle.

[0058] Example 9—4Cr5MoSiV1(H13) steel

[0059] Commercially available ceramic phase powder was weighed according to the proportions in Table 1 and ground in a ball mill for 5 hours to a particle size of 50–90 nm. Then, 16.2 kg of the ground oxide from Table 1 and 122 kg of iron powder with a particle size of 226 μm were placed together in a V-type mixer and thoroughly mixed for 3 hours. The mixture was then further mechanically alloyed in a ball mill for 9 hours to prepare a ceramic phase toughening agent. Afterward, 14.3% by weight of sodium silicate was added to the ceramic phase toughening agent to prepare spherical materials with a diameter of 0.6–0.8 mm, which were then dried. The drying temperature was 164℃, and the drying time was 15 min. Subsequently, the dried spherical materials were simultaneously added to an intermediate frequency furnace along with H13 steel smelting raw materials (30 steel, ferrochrome, ferrosilicon, ferromolybdenum, ferrovanadium, and ferromanganese) to smelt the steel with the target composition shown in Table 2; the addition ratio of spherical materials to smelting raw materials was 1:53. The heating rate during the smelting process is controlled at 17℃ / min. The raw material is heated to 1626℃ and completely melted into molten steel. This is held at that temperature for 15 minutes, then refined using LF and degassed using VD in a 10-ton ladle for 50 minutes before being cast into steel ingots. The ingots are then forged into square billets and further rolled into Φ6.8mm wire rods. These wire rods are pickled and then cold-drawn in four passes to reduce their diameter to 3.0mm, with a minimum reduction of 17% per pass. Every two cold-drawing passes are followed by continuous hydrogen annealing at 654℃ and a speed of 2.5m / min.

[0060] Examples 10-18

[0061] Based on Examples 1-9, the refining process was changed by replacing the "LF refining and VD degassing treatment" steps with electroslag remelting, resulting in Examples 10-18. The types and quality of ceramic phases added in Examples 10-18 are shown in Table 1; the chemical composition of the steel samples obtained in Examples 10-18 is shown in Table 2. The preparation parameters for each step in Examples 10-18 correspond to the relevant parameters in Examples 1-9.

[0062] Table 1. Types and mass percentages of ceramic phases added to 4Cr5MoSiV1

[0063] 1 15 35 50 2 23 50 27 3 50 16 34 4 84 16 0 5 0 75 25 6 31 0 69 7 100 0 0 8 0 100 0 9 0 0 100 10 15 35 50 11 23 50 27 12 50 16 34 13 84 16 0 14 0 75 25 15 31 0 69 16 100 0 0 17 0 100 0 18 0 0 100

[0064] Table 2. Chemical composition (mass percentage) of 4Cr5MoSiV1 steel samples

[0065]

[0066]

[0067] Table 3 shows the hardness data of the surfacing material using 4Cr5MoSiV1 steel solid welding wire.

[0068]

[0069]

[0070] Matters not covered in this invention are common knowledge.

Claims

1. A low-cost method for preparing ceramic phase modified H13 solid welding wire, characterized in that the method includes the following steps: 1) Add the ceramic phase material to a ball mill and ball mill for 3-5 hours to obtain ceramic phase powder; in, The ceramic phase material is one or more of SiO2, MgO and CaO; The particle size range of the ceramic phase powder is 50–100 nm; 2) The ceramic phase powder and the iron-based powder are loaded into a V-type mixer and homogenized for 1 to 5 hours to obtain homogenized powder; wherein the mass ratio of ceramic phase powder to iron-based powder in the homogenized powder is (2-3):(15-20). 3) The homogenized powder is put back into a ball mill for mechanical alloying for 8-15 hours to obtain a ceramic phase toughening agent; 4) Place the ceramic phase toughening agent in a drum, add sodium silicate binder, roll it into spherical material, and then dry it at 140-180℃ for 10-60 minutes to obtain spherical ceramic phase toughening agent particles with a diameter of 0.4-1mm. The amount of sodium silicate binder added is 13-17% of the total weight of the ceramic phase toughening agent; 5) According to the raw material ratio of H13 steel, add the raw materials of the required elements into the melting furnace, and at the same time add the spherical ceramic phase toughening agent particles obtained in step 4). Then, heat the furnace to 1590-1680℃ at a rate of 8-25℃ / min, hold for 15-20 minutes to complete the preliminary melting, obtain molten steel, and then refine it and cast it into ingots. The mass ratio of ceramic phase toughening agent to H13 steel raw material is (10-100):1000; 6) Forge the ingot into a square billet, and then hot roll it into wire rod with a diameter of 5.5 to 8.0 mm; 7) The obtained wire rod is pickled and then cold-drawn to reduce its diameter to 1.2-4.0 mm, with each reduction being 10-30%; finally, welding wire is obtained. In step 1), the mass ratio of the ceramic phase powders is SiO2: 0%–100%; MgO: 0%–100%; CaO: 0%–100%, and none of the three are 0 at the same time; The iron-based powder in step 2) is industrial pure iron powder; The iron-based powder in step 2) has a particle size of 150–250 μm.

2. The low-cost preparation method of ceramic phase modified H13 solid welding wire as described in claim 1, characterized in that: The smelting furnace in step 5) is a medium-frequency furnace.

3. The low-cost preparation method of ceramic phase modified H13 solid welding wire as described in claim 1, characterized in that: The refining process described in step 5) is electroslag remelting or LF refining + VD degassing treatment.

4. The low-cost preparation method of H13 solid welding wire with ceramic phase modification as described in claim 1, characterized in that: Step 7) also includes annealing, specifically continuous hydrogen annealing at a temperature of 600℃~750℃ and a wire running speed of 1~4m / min.

5. The low-cost preparation method of H13 solid welding wire with ceramic phase modification as described in claim 1, characterized in that the diameter of the spherical ceramic phase toughening agent particles is 0.5~0.8 mm.

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