Nickel-containing silicon-aluminum phase reinforced multi-component Fe-Si alloy and preparation method thereof

Abstract

The invention relates to a nickel-containing silicon-aluminum phase enhanced multi-component Fe-Si alloy and a preparation method thereof. The multi-component Fe-Si alloy comprises the following chemical components according to the atomic percent general formula: 18.8% of Fe, 3% of Si, 28.2% of Co, 28.2% of Cr, 18.8% of Ni, 2.9% of Al and 0.1% of B. The preparation method comprises the following steps: gold smelting and solution treatment: under the protection of argon, heating metal raw materials in a smelting furnace until the metal raw materials are molten for alloying, then under the protection of argon, heating a master alloy ingot until the master alloy ingot is completely molten, and carrying out suction casting molding; and under the argon protection environment, an alloy ingot obtained after suction casting is put into a muffle furnace to be subjected to heat preservation for solution treatment, and then thermal deformation, cold deformation and thermal treatment are conducted. The alloy has the advantages of excellent plasticity and good strength. Borides or boron-containing clusters can be dispersed and distributed at the grain boundary to strengthen a matrix, and the grain size can also be regulated and controlled by controlling precipitation and remelting of the borides or the boron-containing clusters.

Description

Technical Field

[0001] The invention belongs to the field of metal material preparation, and in particular relates to a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy and a preparation method thereof. Background Art

[0002] Fe-Si alloy steel is a kind of alloy steel with relatively low carbon content, which plays a very important role in the fields of instruments, machinery, electricity, military industry, etc. In addition, Fe-Si alloy steel not only has low density, good mechanical properties and low manufacturing cost through the combination of metal and non-metal elements, but also has uniform organizational structure and good casting fluidity, so it is widely used in the power industry.

[0003] With the addition of Si element, the magnetic properties of the strip can be effectively improved while the mechanical properties and anti-oxidation burning ability of the strip can be deteriorated, causing the strip to become brittle. In recent years, multi-component alloys, as a new metal alloy design concept, have attracted extensive attention from researchers because they can mix a variety of alloy elements and have good strength and plasticity matching, excellent anti-oxidation properties, etc. In addition, multi-component alloys can also form single-phase solid solution structures with face-centered cubic (FCC), body-centered cubic (BCC) and hexagonal close-packed (HCP) structures through the matching and regulation of different alloying elements.

[0004] In the prior art, Patent Publication No.: CN110720130A discloses an Fe-Si based alloy and a method for manufacturing the same. The alloy has a chemical formula of Fe100a-bcde-fSiaMbLcM'dM"eRf, wherein M is one or both of Cr and Mo; L is one or both of Co and Ni; M' is selected from Al, Mn, Cu, Ge, Ga and combinations thereof; M" is selected from Ti, V, Hf, Nb, W and combinations thereof; R is selected from B, Zr, Mg, P, Ce and combinations thereof; the alloy composition has a large number of selectable elements, and the alloy has limited plasticity. Patent Publication No.: CN109897997A discloses a lithium-containing aluminum-magnesium-silicon dual-phase reinforced eutectic lightweight medium-entropy alloy and a method for preparing the same. The component molecular expression of the lightweight eutectic medium-entropy alloy is Al80Mg10Cu2Zn2Si5Li1. The designed alloy is a dual-phase reinforced eutectic alloy with good fluidity and excellent casting performance. Patent Publication No.: CN110607496A, discloses a method for preparing Fe-Si alloy with Goss texture, which effectively overcomes the influence of Kirkendall effect by using the early activation treatment of siliconizing agent and substrate and the precise design of siliconizing agent, realizes the balanced diffusion of Fe-Si at a relatively low temperature of about 800°C, and prepares a high-quality, non-porous siliconizing layer on the surface of 3% oriented silicon steel. The above-mentioned Fe-Si-based alloys cannot have good strength and plastic matching at the same time. Summary of the invention

[0005] The purpose of the present invention is to provide a multi-component Fe-Si alloy reinforced with nickel-silicon-aluminum phase and a preparation method thereof. Based on the combination mode of metal and non-metallic elements in the Fe-Si alloy, the preparation process is simplified. The prepared alloy has a dual-phase structure of an FCC matrix and a nickel-silicon-aluminum phase, and has good strength and plasticity matching. The addition of Cr and Si elements can improve the oxidation resistance and corrosion resistance of the alloy.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions:

[0007] A multi-component Fe-Si alloy containing nickel, silicon and aluminum phase reinforcement, wherein the chemical composition of the multi-component Fe-Si alloy is generally represented by the formula of Fe 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B 0.1 .

[0008] The multi-component Fe-Si alloy has a dual-phase structure of a disordered face-centered cubic FCC matrix and a nickel-silicon-aluminum phase, and boron-containing clusters are dispersedly distributed at grain boundaries to strengthen the matrix.

[0009] A method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy comprises the following steps:

[0010] 1) Gold smelting and solid solution treatment: Fe, Si, Co, Cr, Ni, Al and B elements are used as raw materials, and the metal raw materials are heated to melt in a smelting furnace under argon protection for alloying, and the smelting is repeated at least 4 times to obtain a master alloy ingot; then, under argon protection, the master alloy ingot is heated to a completely molten state, and suction-casted to obtain a suction-cast alloy ingot; under argon protection, the suction-cast alloy ingot is placed in a muffle furnace for heat preservation and solid solution treatment;

[0011] 2) Hot deformation and cold deformation: The alloy ingot after solution treatment is hot deformed in a certain temperature window; the alloy ingot after hot deformation is pickled or grinded by a grinder to remove the oxide scale and then cold deformed;

[0012] 3) Heat treatment: The alloy plate after cold deformation is subjected to normalizing treatment, or aging heat treatment is performed after normalizing treatment.

[0013] The smelting furnace described in step 1) is a vacuum arc melting furnace or a vacuum induction melting furnace.

[0014] In step 1), a vacuum arc melting furnace is selected for melting and suction casting, or a vacuum induction melting furnace is selected for casting to form the alloy.

[0015] The solution treatment in step 1) is to keep the temperature at 1200-1300°C for more than 24 hours, and then quench with water. This can reduce element segregation, avoid the formation of impurity and harmful phases, and ensure the precipitation of a unique nickel-containing silicon-aluminum phase on the FCC matrix in combination with subsequent normalization and aging treatments.

[0016] The hot deformation described in step 2) is repeated hot forging or multiple hot rolling deformation in a temperature window of 1050-1150°C, with a total deformation of 50%-60%; the cold deformation described in step 2) is cold rolling deformation at room temperature or in a liquid nitrogen immersion environment, with a total deformation of 70%-80%.

[0017] The normalizing treatment in step 3) is annealing at 700-1000°C for 0.5-4h and then water quenching. The recrystallization volume fraction of the FCC matrix can be controlled, the grain size can be controlled, and the matrix can be ensured to form uniformly distributed fine grains.

[0018] In step 3), the normalization treatment is followed by aging heat treatment, which can control the size and distribution of the boride or boron-containing clusters, that is, the aging heat treatment is used to control the size and distribution of the nickel-containing silicon-aluminum phase and improve the mechanical properties. The aging treatment can sometimes be omitted. The aging heat treatment is aging at 400-600°C for 0.5-48h and then quenching in water.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy prepared by the present invention comprises a dual-phase structure of a disordered face-centered cubic FCC matrix and a nickel-silicon-aluminum phase, and boron-containing clusters are dispersedly distributed at the grain boundaries to strengthen the matrix. The grain size of the alloy can also be regulated by controlling the precipitation and remelting of borides or boron-containing clusters.

[0021] 2. The present invention adopts a unique ratio of seven components, Fe, Si, Co, Cr, Ni, Al, and B, and obtains a nickel-silicon-aluminum phase-reinforced two-phase multi-component Fe-Si alloy through alloy proportioning and smelting, solid solution treatment, hot rolling deformation and room temperature rolling, normalizing heat treatment and aging heat treatment. The alloy replaces the Fe element with three elements of CoCrNi, and takes four components as the matrix, and does not form the BCC structure in the traditional Fe-Si alloy, but forms a disordered FCC structure, and inherits good elongation at break.

[0022] 3. The present invention adds Cr and Si elements. The addition of Cr and Si elements can improve the oxidation resistance and corrosion resistance of the alloy. However, due to the characteristics of multi-component alloys, hard and brittle phases such as Cr-rich σ phase and Laves phase are not formed in the organization, but a nickel-containing silicon-aluminum phase reinforced matrix is ​​formed. By adding trace element B element to solid-dissolve into the matrix and precipitate uniformly at the grain boundaries as boride or boron-containing clusters, the formation of silicon-containing compounds to reduce performance is avoided; and the addition of B element can strengthen the grain boundaries, effectively improve the tensile strength of the alloy without significantly deteriorating the plasticity of the alloy. The present invention can disperse borides or boron-containing clusters at the grain boundaries to strengthen the matrix, and the grain size can also be controlled by controlling the precipitation and remelting of borides or boron-containing clusters.

[0023] 4. The alloy prepared by the present invention has excellent and stable performance, simple preparation process, strong safety, and moderate price of alloy raw materials. The nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy prepared by the present invention has excellent plasticity and good strength, and has engineering application prospects in the field of Fe-Si alloy structural materials under room temperature and low temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Fe 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B 0.1 Scanning electron microscope (SEM) microstructure of multi-component Fe-Si alloy.

[0025] Figure 2 Fe 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B 0.1 Static tensile engineering stress-strain curve of multi-component Fe-Si alloy. DETAILED DESCRIPTION

[0026] The present invention is described in detail below in conjunction with the accompanying drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0027] Example 1

[0028] A method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy comprises the following steps:

[0029] 1) Formulated to be Fe 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B0.1 (at.%) alloy, wherein the subscript of each element is the atomic percentage of each element, is repeatedly smelted in a vacuum arc melting furnace for 5 times to obtain a master alloy ingot; the smelted master alloy ingot is placed on a suction casting mold and suction-casted in a vacuum arc melting furnace to obtain a multi-component Fe-Si alloy suction casting ingot, and the size of the suction casting copper mold is selected to be 10mm×10mm×120mm;

[0030] 2) The alloy suction cast ingot is vacuum sealed and filled with argon, and then solution treated at 1200℃ for 24 hours and then quenched with water. This can reduce element segregation and avoid the formation of impurities and harmful phases. The subsequent normalizing and aging treatments can ensure the precipitation of unique nickel-silicon-aluminum phases on the FCC matrix. The alloy is hot-rolled in a temperature window of 1100℃ with a deformation of 50%. The hot-deformed alloy ingot is pickled or grinded with a grinder to remove the oxide scale, and then cold-rolled in a liquid nitrogen immersion environment with a deformation of 70%. The thinned sheet is annealed at 1000℃ for 1 hour and then quenched with water. It is then aged at 600℃ for 12 hours to obtain a multi-component Fe-Si alloy reinforced with nickel-silicon-aluminum phases.

[0031] 3) A dog-bone tensile specimen with a thickness of 1 mm was cut from a multi-component Fe-Si alloy sheet by electrospark machining. The gauge length, width and thickness of the tensile specimen were 10 mm, 3 mm and 1 mm, respectively. The specimen was tested on a universal testing machine (CMT4305) at a speed of 1 × 10 -3 The static tensile mechanical properties test was carried out at a fixed strain rate of / s.

[0032] Experimental test analysis:

[0033] The nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy prepared in this embodiment was experimentally tested. Figure 1 The SEM microstructure of the prepared multi-component Fe-Si alloy shows that the prepared multi-component Fe-Si alloy contains a dual-phase structure of a disordered face-centered cubic FCC matrix and a nickel-silicon-aluminum phase. According to the tensile test results, the prepared multi-component Fe-Si alloy has a yield strength of 335 MPa, a tensile strength of 694 MPa, and an elongation at break of 38.7%.

[0034] Example 2

[0035] A method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy comprises the following steps:

[0036] 1) Formulated to be Fe 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B 0.1(at.%), wherein the subscript of each element is the atomic percentage of each element, and the master alloy ingot is obtained after repeated melting in a vacuum arc melting furnace for 5 times; the melted master alloy ingot is placed on a suction casting mold in a vacuum arc melting furnace for suction casting to obtain a multi-component Fe-Si alloy suction casting ingot;

[0037] 2) Cutting a 5 mm thick alloy suction casting ingot, sealing it in a vacuum tube and filling it with argon, solution treating it at 1250°C for 24 hours, and then quenching it with water; hot rolling the alloy in a temperature window of 1100°C with a deformation of 60%; pickling or grinding the hot-deformed alloy ingot to remove the oxide scale, and then cold rolling it in a liquid nitrogen immersion environment with a deformation of 75%, and annealing the thinned sheet at 700°C for 1 hour, and then quenching it with water to obtain a multi-component Fe-Si alloy reinforced with nickel, silicon, and aluminum phases;

[0038] 3) Cutting a dog-bone tensile specimen with a thickness of 1 mm from the multi-component Fe-Si alloy sheet by an electrospark machining method, wherein the gauge length, width and thickness of the tensile specimen are 10 mm, 3 mm and 1 mm, respectively, and using a universal testing machine (CMT4305) at a speed of 1×10 -3 The static tensile mechanical properties test was carried out at a fixed strain rate of / s.

[0039] The nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy prepared in this embodiment was experimentally tested, and the prepared multi-component Fe-Si alloy contained a disordered face-centered cubic FCC matrix and a dual-phase structure containing nickel-silicon-aluminum phase. According to the tensile test results, the yield strength of the prepared multi-component Fe-Si alloy was 706MPa, the tensile strength was 846MPa, and the elongation at break was 23.5%.

[0040] Example 3

[0041] A method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy comprises the following steps:

[0042] 1) Formulated to be Fe 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B 0.1 (at.%) alloy, wherein the subscript of each element is the atomic percentage of each element, is repeatedly melted 5 times in a vacuum arc melting furnace to obtain a multi-component Fe-Si alloy master alloy ingot;

[0043] 2) vacuum sealing a master alloy ingot with a thickness of 12 mm and filling it with argon, solution treating it at 1250° C. for 24 hours, and then water quenching; hot rolling the alloy in a temperature window of 1100° C. with a deformation amount of 50%; pickling or grinding the hot-deformed alloy ingot to remove the oxide scale, and then cold rolling it at room temperature with a deformation amount of 80%, and annealing the thinned sheet at 700° C. for 1 hour, and then water quenching, and then aging at 600° C. for 12 hours to obtain a nickel-containing, silicon-aluminum phase-reinforced multi-component Fe-Si alloy;

[0044] 3) Cutting a dog-bone tensile specimen with a thickness of 1 mm from the multi-component Fe-Si alloy sheet by an electrospark machining method, wherein the gauge length, width and thickness of the tensile specimen are 10 mm, 3 mm and 1 mm, respectively, and using a universal testing machine (CMT4305) at a speed of 1×10 -3 The static tensile mechanical properties test was carried out at a fixed strain rate of / s.

[0045] The nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy prepared in this embodiment was experimentally tested, and the prepared multi-component Fe-Si alloy contained a disordered face-centered cubic FCC matrix and a dual-phase structure containing nickel-silicon-aluminum phases. According to the tensile test results, the yield strength of the prepared multi-component Fe-Si alloy was 646MPa, the tensile strength was 798MPa, and the elongation at break was 24.1%.

[0046] Example 4

[0047] A method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy comprises the following steps:

[0048] 1) Formulated to be Fe 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B 0.1 (at.%) alloy, wherein the subscript of each element is the atomic percentage of each element, is repeatedly melted 5 times in a vacuum arc melting furnace to obtain a multi-component Fe-Si alloy master alloy ingot;

[0049] 2) vacuum sealing a mother alloy ingot with a thickness of about 12 mm and filling it with argon, solution treating it at 1260° C. for 24 hours, and then water quenching; hot rolling the alloy in a temperature window of 1100° C., with a deformation amount of about 55%; pickling or grinding the hot-deformed alloy ingot to remove the oxide scale, and then cold rolling it at room temperature, with a deformation amount of about 75%, and annealing the thinned sheet at 900° C. for 1 hour, and then water quenching, and then aging at 600° C. for 24 hours to obtain a multi-component Fe-Si alloy reinforced with nickel, silicon, and aluminum phases;

[0050] 3) Cut a dog-bone tensile specimen with a thickness of about 1 mm from the multi-component Fe-Si alloy sheet by an electrospark machining method. The gauge length, width and thickness of the tensile specimen are about 10 mm, 3 mm and 1 mm, respectively. Use a universal testing machine (CMT4305) with a 1×10 -3 s -1 Static tensile mechanical properties tests were carried out at a fixed strain rate.

[0051] The nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy prepared in this embodiment was experimentally tested, and the prepared multi-component Fe-Si alloy contained a disordered face-centered cubic FCC matrix and a dual-phase structure containing nickel-silicon-aluminum phase. According to the tensile test results, the yield strength of the prepared multi-component Fe-Si alloy was 386MPa, the tensile strength was 751MPa, and the elongation at break was 34.3%.

[0052] In summary, the nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy and the preparation method thereof of the present invention are simple and feasible. The microstructure after the deformation heat treatment comprises a disordered face-centered cubic FCC matrix and a dual-phase structure of the nickel-silicon-aluminum phase, and the boron-containing clusters are dispersedly distributed at the grain boundaries to strengthen the matrix. The obtained alloy has both high strength and good plasticity, stable performance, simple preparation process, strong safety, and is expected to be produced and applied in the field of engineering applications. The raw materials used are non-toxic and harmless, moderately priced, and low industrial investment.

[0053] The above describes the embodiments of the present invention in conjunction with the drawings, but the present invention is not limited to the above embodiments. Without departing from the principles of the present invention, any changes, substitutions and modifications made according to the content of the present invention belong to the protection scope of the present invention.

Claims

1. A multi-component Fe-Si alloy reinforced with nickel, silicon and aluminum phases, characterized in that: The chemical composition of the multi-component Fe-Si alloy is generally represented by the formula of Fe in atomic percentage. 18.8 Si3Co 28.2 Cr 28.2 Ni 18.8 Al 2.9 B 0.1 .

2. A nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy according to claim 1, characterized in that: The multi-component Fe-Si alloy has a dual-phase structure of a disordered face-centered cubic FCC matrix and a nickel-silicon-aluminum phase, and boron-containing clusters are dispersedly distributed at grain boundaries to strengthen the matrix.

3. A method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy as claimed in claim 1, characterized in that: The following steps are involved: 1) Gold smelting and solution treatment: Fe, Si, Co, Cr, Ni, Al and B elements are used as raw materials, and the metal raw materials are heated to melt in a smelting furnace under argon protection for alloying, and the smelting is repeated at least 4 times to obtain a master alloy ingot; Then, under the protection of argon, the master alloy ingot is heated to a completely molten state, and suction-casted to obtain a suction-cast alloy ingot; under the protection of argon, the suction-cast alloy ingot is placed in a muffle furnace for heat preservation and solid solution treatment; 2) Hot deformation and cold deformation: The alloy ingot after solution treatment is hot deformed in a certain temperature window; the alloy ingot after hot deformation is pickled or grinded by a grinder to remove the oxide scale and then cold deformed; 3) Heat treatment: The alloy plate after cold deformation is subjected to normalizing treatment, or aging heat treatment is performed after normalizing treatment.

4. The method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy according to claim 3, characterized in that: The smelting furnace described in step 1) is a vacuum arc melting furnace or a vacuum induction melting furnace.

5. The method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy according to claim 3, characterized in that: In step 1), a vacuum arc melting furnace is selected for melting and suction casting, or a vacuum induction melting furnace is selected for casting to form the alloy.

6. The method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy according to claim 3, characterized in that: The solution treatment in step 1) is performed by heat preservation at 1200-1300° C. for more than 24 hours, followed by water quenching after the heat preservation.

7. The method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy according to claim 3, characterized in that: The hot deformation described in step 2) is repeated hot forging or multiple hot rolling deformation in a temperature window of 1050-1150°C, with a total deformation of 50%-60%; the cold deformation described in step 2) is cold rolling deformation at room temperature or in a liquid nitrogen immersion environment, with a total deformation of 70%-80%.

8. The method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy according to claim 3, characterized in that: The normalizing treatment in step 3) is annealing at 700-1000° C. for 0.5-4 h and then water quenching.

9. The method for preparing a nickel-silicon-aluminum phase-reinforced multi-component Fe-Si alloy according to claim 3, characterized in that: In step 3), normalizing treatment is performed and then aging heat treatment is performed. The aging heat treatment is performed at 400-600° C. for 0.5-48 hours and then water quenching.

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