CN-121976082-A - Preparation method of iron-based amorphous nanocrystalline master alloy based on resource recycling

Abstract

The invention belongs to the technical field of amorphous nanocrystalline master alloy smelting, and particularly discloses a resource recycling-based preparation method of an iron-based amorphous nanocrystalline master alloy, which comprises the technological means of waste pretreatment, low-grade niobium-silicon-iron pretreatment, feSiNb intermediate alloy non-vacuum smelting, iron-based nanocrystalline master alloy vacuum smelting and the like, and the iron-based amorphous nanocrystalline master alloy is prepared by adopting waste silicon steel, photovoltaic waste silicon powder and low-grade niobium-silicon iron which are relatively low in cost to replace the existing industrial pure iron, industrial silicon and high-grade niobium-iron as raw materials, so that the efficient recycling of waste silicon steel materials, photovoltaic waste silicon powder and low-grade niobium-silicon iron and the effective removal of inclusion and harmful element Al in molten steel in the smelting process are finally realized, and finally the high-quality iron-based amorphous nanocrystalline master alloy with the aluminum content of less than or equal to 30ppm, the total oxygen content of less than or equal to 10ppm, the inclusion size of less than 6 mu m is prepared, and the method has the beneficial effects of low production cost, simple production working procedures, high purity of master alloy and the like, and is beneficial to industrialized popularization.

Inventors

• SUN HAIBO
• LI JIN
• CHENG TIANHONG
• Xing Kaida

Assignees

• 佛山大学

Dates

Publication Date

20260505

Application Date

20260202

Claims (3)

1. 1. The preparation method of the iron-based amorphous nanocrystalline master alloy based on resource recycling is characterized by comprising the following steps of: S1, pretreating waste, namely, the waste comprises recovered waste silicon steel bulk material and photovoltaic waste silicon powder, wherein the recovered waste silicon steel bulk material is pressed into waste silicon steel pressing blocks by a press, and the recovered photovoltaic waste silicon powder is firstly prepared by mechanically mixing the photovoltaic waste silicon powder, epoxy resin and ethanol according to the mass ratio of (0.8-1.5) (1.5-4.0), then pressing the mixture into blocks by a roll ball press, and then drying and curing the block mixture at 200-250 ℃ for 2-3 hours to obtain the photovoltaic waste silicon powder mixture pressing blocks with the compressive strength of 1-4N; S2, pretreating low-grade niobium-silicon iron, namely mechanically mixing the low-grade niobium-silicon iron, quicklime and ferric oxide powder (3.0-4.5) in a mass ratio of (1.5-2.5) to obtain a low-grade niobium-silicon iron mixture; S3, feSiNb intermediate alloy non-vacuum smelting, namely, preparing smelting raw materials according to the components of the target FeSiNb intermediate alloy, wherein the smelting raw materials comprise a waste silicon steel pressing block, a photovoltaic waste silicon powder mixture pressing block and a low-grade niobium-silicon-iron mixture; S4, performing vacuum smelting on the iron-based nanocrystalline master alloy, namely performing batching on smelting raw materials according to components of a target iron-based nanocrystalline master alloy FeSiBCuNb, wherein the smelting raw materials comprise FeSiNb master alloy, ferroboron and electrolytic copper, placing the FeSiNb master alloy at the bottom of an intermediate frequency vacuum induction furnace, covering the furnace cover to start vacuumizing until the vacuum degree is 10-60 Pa, adjusting the heating power of the intermediate frequency vacuum induction furnace to 100-300kW to raise the temperature to 1510+/-10 ℃, performing vacuum refining on the raw materials in the furnace for 15-25 min, obtaining FeSiNb high-temperature solution after the raw materials in the furnace are cleaned, then opening the furnace cover to break the vacuum state, manually removing primary vacuum refined scum on the surface of the FeSiNb high-temperature solution, adding ferroboron and electrolytic copper, covering the furnace cover again to start vacuumizing until the vacuum degree is 10-60 Pa, adjusting the heating power of the intermediate frequency vacuum induction furnace to 70-120kW, performing vacuum refining on the raw materials in the furnace for 15-25 min, obtaining FeSiBCuNb high-temperature solution of the iron-based nanocrystalline master alloy after the raw materials in the furnace are cleaned, performing power failure, cooling, performing vacuum refining on the iron-based nanocrystalline master alloy in the furnace to reduce the temperature of the furnace to 34-temperature to 5+/-10 ℃ until the temperature of the iron-based nanocrystalline master alloy is within the range of 5+/-10 ℃, opening the surface of the iron-based nanocrystalline master alloy is subjected to vacuum state, and performing vacuum refining to remove the secondary vacuum state of the iron-based nanocrystalline master alloy to be in the vacuum state of the iron-based nanocrystalline master alloy after the surface of the FeSiNb is cut to be in the range of the vacuum state of the vacuum master alloy, and reaching the vacuum state of the final die, and performing vacuum state of the iron-based nanocrystalline master alloy is removed.
2. 2. The method for preparing the iron-based amorphous nanocrystalline master alloy based on resource recycling according to claim 1, wherein in the step S1, the waste silicon steel pressing block is cuboid or cylindrical block, the ratio of the maximum linear dimension of the block cross section to the diameter D of a non-vacuum intermediate frequency furnace mouth is in the range of 0.2-0.5, the granularity of the photovoltaic waste silicon powder mixture pressing block is 10-50 mm, and the cross section of the photovoltaic waste silicon powder mixture pressing block is rectangular or elliptical.
3. 3. The method for preparing the iron-based amorphous nanocrystalline master alloy based on resource recycling according to claim 1, wherein in the step S3, the target component of FeSiNb intermediate alloy is FeSi 8.0~15.0wt% Nb 4.5~5.5wt% , the distribution mode of the waste silicon steel pressing block, the photovoltaic waste silicon powder mixture pressing block and the low-grade niobium-silicon-iron mixture in the non-vacuum medium-frequency induction furnace is that the photovoltaic waste silicon powder mixture pressing block accounting for 35-55% of the total added weight of the photovoltaic waste silicon powder mixture pressing block is paved on the furnace bottom, all the waste silicon steel pressing blocks are placed on the photovoltaic waste silicon powder mixture pressing block, and finally the low-grade niobium-silicon-iron mixture is poured into a gap between the waste silicon steel pressing blocks, and the non-vacuum smelting process comprises: Feeding power to a non-vacuum intermediate frequency induction furnace, regulating heating power to 300-500kW to raise the temperature to 1510-1540 ℃, blowing argon from the bottom of the non-vacuum intermediate frequency induction furnace for 20-30 min after raw materials in the furnace are converted into clear, performing primary argon blowing refining, wherein the primary argon blowing pressure is 0.6-1.0 MPa, adding 2-3 batches of rest photovoltaic waste silicon powder mixture pressed blocks to scum of the primary argon blowing refining on the liquid surface of steel, reducing the heating power of the intermediate frequency induction furnace to 200-300 kW, heating the intermediate frequency induction furnace to 30-60kW to keep the temperature of molten steel in the furnace, blowing argon from the bottom of the non-vacuum intermediate frequency induction furnace for 25-35 min, performing secondary argon blowing refining, wherein the secondary argon blowing pressure is 0.1-0.4 MPa, and finally closing intermediate frequency induction heating, manually removing the refined scum on the liquid surface of the molten steel when the molten steel temperature is 1440+/-15 ℃, and casting the molten steel into a steel ingot mould to form FeSiNb intermediate alloy.

Description

Preparation method of iron-based amorphous nanocrystalline master alloy based on resource recycling Technical Field The invention relates to the technical field of amorphous nanocrystalline master alloy smelting, in particular to a preparation method of an iron-based amorphous nanocrystalline master alloy based on resource recycling. Background The iron-based amorphous nanocrystalline soft magnetic material (generally composed of Fe, cu, nb, si, B elements and the like) is a biphase structure material which is formed into an amorphous state through rapid cooling and then is subjected to annealing treatment to separate out nanocrystalline grains. Compared with the traditional magnetic materials such as pure iron (Fe), iron silicon (FeSi), iron silicon aluminum (FeSiAl), ferrite and the like, the iron-based amorphous nanocrystalline soft magnetic material has excellent characteristics such as low coercivity H c (< 0.8A/m), low hysteresis expansion coefficient lambda s (-0 ppm), high magnetic permeability, high crystallization temperature, excellent frequency characteristic and the like, has been widely applied to the preparation of key magnetic components in the field of high-frequency power electronics, such as DC/DC conversion circuits, inversion inductors, common mode inductors and high-precision current sensors in on-board chargers of switching power supplies, photovoltaic inverters and new energy automobiles, and is an ideal material conforming to the development trend of the modern power electronics industry. At present, commercial iron-based amorphous nanocrystalline soft magnetic materials are mostly prepared by adopting a horizontal casting method, the product is a thin strip (the thickness is generally less than 23 mu m), and high requirements are put on the purity of smelting raw materials, so that the purchase cost of smelting raw materials of production enterprises is also increased. In view of the above, the invention provides a method for preparing high-quality iron-based amorphous nanocrystalline master alloy based on resource recycling, so as to reduce the production cost of iron-based amorphous nanocrystalline product production enterprises. For example, chinese patent publication No. CN 103014477B discloses a method for smelting an iron-based nanocrystalline master alloy. The method comprises the steps of placing raw materials in a furnace according to process requirements, vacuumizing, transmitting electricity, adjusting heating power and heating time, adding the rest pure iron into the furnace in the process, keeping the temperature for 15 minutes when the temperature reaches 1520+/-10 ℃, cooling to 1460+/-10 ℃ in a power cut mode, adding metal silicon, adjusting the heating power to 100kW, melting for 30 seconds, adding electrolytic copper into the furnace after the time is over, ensuring the heating power to be 100kW, melting for 30 seconds, cooling to 1360+/-10 ℃ in a power cut mode, opening a furnace cover, continuously cooling to 1280+/-10 ℃, and pouring molten steel into a steel ingot mold after tapping. Therefore, the method does not consider a method for removing aluminum element in smelting raw materials, namely, the method is only applicable to adopting high-grade ferrocolumbium as raw materials. As disclosed in chinese patent publication No. CN118268517a, an iron-based amorphous or nanocrystalline strip and a method for preparing the same are disclosed, wherein an iron-based amorphous or nanocrystalline strip is prepared from electrical steel waste, the silicon steel waste is subjected to slag-making remelting and impurity removal as an amorphous or nanocrystalline master alloy, then component design is performed, arc melting is adopted to uniformly mix the design components, and finally a single-roller melt quenching method is performed to prepare the amorphous or nanocrystalline strip, so as to solve the problems of waste of electrical steel waste resources and high production cost for preparing the iron-based amorphous/nanocrystalline. However, the method does not give a specific smelting process flow and a reasonable process parameter range. As disclosed in chinese patent publication No. CN 115976432a, a low-aluminum high-purity iron-based amorphous nanocrystalline master alloy and a preparation method thereof are disclosed, which are dealuminized and modified inclusions are removed by technological means such as reasonable distribution, adding iron oxide powder, feeding calcium wires, slagging, bottom blowing argon and the like, and floating upward, thereby reducing aluminum in the master alloy and improving purity and quality of the master alloy. The method discloses two slag former systems, the smelting process is complicated, and the slag former system contains 5wt% of CaF, which is easy to cause corrosion of furnace lining and form new inclusion. Disclosure of Invention In order to solve the technical problems, the invention provides a preparation method of an iron-bas