CN113388766B - A kind of manganese-based nanocrystalline/amorphous composite structure alloy and preparation method thereof - Google Patents

Abstract

The application belongs to the technical field of composite structure alloy, and particularly relates to a manganese-based nanocrystalline/amorphous composite structure alloy and a preparation method thereof. The manganese-based nanocrystalline/amorphous composite structural alloy has a general formula as follows: mn _bal Si _a B _b M _c R _d T _e (ii) a bal is more than or equal to 55; a is more than or equal to 10 and less than 30; b is more than 5 and less than or equal to 12; m is selected from one or more of Fe, Co, Ni and Cr, and c is more than or equal to 0 and less than or equal to 25; r is selected from one or more of Ag, Mg and Cu, and d is more than or equal to 0 and less than or equal to 5; t is selected from one or more of Zr, Ti, V, Nb, Hf and Ta, and e is more than or equal to 0 and less than or equal to 8. The manganese-based nanocrystalline/amorphous composite structure alloy has excellent magnetic transformation characteristics and rich magnetic structures, provides the possibility of a wide-temperature-range zero-magnetic-field-stability sigramine magnetic structure material, and has academic research value and potential practical application value in the field of spintronics.

Description

A kind of manganese-based nanocrystalline/amorphous composite structure alloy and preparation method thereof

technical field

The application belongs to the technical field of composite structure alloys, and in particular relates to a manganese-based nanocrystalline/amorphous composite structure alloy and a preparation method thereof.

Background technique

In alloys or composite materials, one of the components is nanosized on one-dimensional, two-dimensional or three-dimensional scales, often showing more excellent structure and properties. The preparation of nanocrystalline/amorphous dual-phase composite materials of Fe-based, Co-based, Mg-based, Al-based alloys, etc., shows particularly outstanding properties. Mn is a metal element with peculiar structure and magnetism among the transition metal elements. However, there are existing literature reports on manganese-based amorphous alloys, and mainly use magnetron sputtering and mechanical ball milling to prepare binary systems (such as Mn-Si, Mn-Ge, Mn-C, Mn-B, Mn- Zr, Mn-Y, etc.) manganese-based amorphous alloy films or powders, and found spin glass transition behavior in these manganese-based amorphous samples, but did not involve the exploration of manganese-based amorphous/nanocrystalline material particles.

Magnetic skyrmions are vortex-like magnetic structures with topologically protective properties. This magnetic structure is expected to be used as a new generation of magnetic storage due to its non-trivial topological protection properties, local particle properties (minimum size up to 3 nm), and flexible dynamic properties (which can be regulated by magnetic fields, electric fields, currents, etc.). The basic unit realizes high-density, low-power, non-volatile information storage. In addition to magnetic storage, the rich and novel physical properties of skyrmions can also be used to realize logical operations, transistor-like structures, nano-oscillators, etc. In the field of electronics, the dual properties of electron charge and spin can be used at the same time to design more functional Efficient Microelectronics.

However, the topological magnetic structure of skyrmions in most of the magnetic skyrmion materials discovered so far needs to be stabilized under the dual action of low temperature and external magnetic field. The magnetic field is stabilized, and it can be seen that the material of magnetic skyrmions that can be stable at zero magnetic field at room temperature is extremely rare. Therefore, it is a technical problem to be solved urgently by those skilled in the art to find a skyrmion magnetic structure material with stable zero magnetic field in a wide temperature range.

SUMMARY OF THE INVENTION

In view of this, the present application provides a manganese-based nanocrystalline/amorphous composite structure alloy and a preparation method thereof, the composite structure alloy has excellent magnetic transition characteristics and rich magnetic structure, and provides a wide temperature range zero magnetic field The possibility of stable skyrmion magnetic structural materials has academic research value and potential practical application value in the field of spintronics.

A first aspect of the present application provides a manganese-based nanocrystalline/amorphous composite structure alloy, the general formula of which is as follows:

Mn _bal Si _a B _b M _c R _d T _e ;

In the general formula, Mn _bal represents an alloy system with Mn as the main component, and its atomic mole number bal≥55; the mole number a of Si element satisfies 10≤a<30; the mole number b of B element satisfies 5<b ≤12; M is selected from one or more of Fe, Co, Ni or Cr elements, and the number of atomic moles c is 0≤c≤25; R is selected from one or more of Ag, Mg and Cu elements , and its atomic mole number d is 0≤d≤5; T is selected from one or more of Zr, Ti, V, Nb, Hf and Ta, and the atomic number e satisfies 0≤e≤8; bal+ The sum of a+b+c+d+e has 100 atomic moles.

In another embodiment, the M element and the T element exist simultaneously; the M element and the T element do not exist simultaneously; the R element and the T element exist simultaneously.

In another embodiment, the M is selected from Fe.

In another embodiment, the R is selected from Ag or Cu.

In another embodiment, the T is selected from one of Nb, Zr or V.

Specifically, the M and the T elements exist at the same time, and the synergistic effect of the two can effectively promote the nucleation and precipitation of manganese or manganese-silicon, so that the amorphous alloy is transformed from single-level crystallization to double-level crystallization.

In another embodiment, the chemical formula of the manganese-based nanocrystalline/amorphous composite structure alloy is: Mn ₆₈ Si ₂₅ B ₇ , Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ , Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ or Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ ; wherein, EM is one or more of Nb, Zr and V.

Specifically, the Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ , where EM is one or more of Nb, Zr and V, including Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₃ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Zr ₃ or Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ V ₃ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₁ Zr ₁ V ₁ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₂ Zr ₁ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₁ Zr ₂ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Zr ₂ V ₁ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Zr ₁ V ₂ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₂ V ₁ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₁ V ₂ .

A second aspect of the present application provides a method for preparing a manganese-based nanocrystalline/amorphous composite structure alloy, including:

Step 1. According to the ratio of the manganese-based nanocrystalline/amorphous composite structure alloy, the raw materials of the manganese-based nanocrystalline/amorphous composite structure alloy are mixed and processed, and then the amorphous alloy is obtained after rapid melt quenching Strip;

Step 2, according to the thermal characteristic temperature value of the amorphous alloy strip, perform annealing heat treatment on the amorphous alloy strip to obtain a manganese-based nanocrystalline/amorphous composite structure alloy.

In another embodiment, in step 1, the treatment is arc melting treatment or magnetron sputtering treatment.

Specifically, the arc smelting treatment includes: according to the atomic percentage ratio of each element of the manganese-based nanocrystalline/amorphous composite structure alloy, calculating the weight percentage ratio converted into atoms, and then multiplying by 10g to obtain each elemental element The required weights were prepared using the raw materials given in Table 1. After each raw material is batched according to the atomic percentage, it is arc smelted using a WK-IIA non-consumable vacuum arc smelting furnace. In order to ensure the quality of the master alloy of the amorphous alloy strip, the furnace body is evacuated before smelting to make the vacuum degree below 3.0×10 ^-4 Pa, and then high-purity argon gas (purity 99.99%) is introduced here. In addition to being a protection, argon also acts as an arc ignition and heat source. When each batch of samples is smelted, a smelting pot is reserved to hold the titanium ingots, and the titanium ingots are first smelted during smelting to absorb the residual oxygen in the smelting furnace, and then the samples are smelted by electric arc, and each sample must be turned over Repeated smelting 3 to 4 times to ensure the uniformity of alloy composition, reduce the composition segregation of alloy elements, and obtain high-quality amorphous alloy strips.

Specifically, the rapid quenching of the melt is a conventional copper roll rapid quenching method.

Table 1

In another embodiment, the thickness of the amorphous alloy strip is 22-25 mm; the width of the amorphous alloy strip is 1.2-1.5 mm.

Specifically, in step 1 of the present application, the rapid quenching of the melt is a copper roll rapid quenching method, and the copper roll rapid quenching method uses an NMS-II induction type solution rapid quenching strip machine for preparing the amorphous alloy strip. Before stripping, turn the copper roll up at a linear speed of less than 15m/s, lightly polish off the oxide layer on the surface of the copper roll with sandpaper greater than 2000 mesh, and clean the surface of the copper roll with gauze dipped in acetone. The master alloy is broken into small pieces with a diameter of about 5-8mm, put into a quartz tube, and then the quartz tube is fixed in the heating induction coil above the copper roller. The diameter of the round-hole quartz tube nozzle used is 0.35-0.45mm, and the process parameters such as the height of the nozzle from the copper roller to 0.25-0.30mm, the line speed of the copper roller to 45-60m/s, and the pressure difference of the spray belt to be 0.03-0.08MPa are flexibly adjusted. Close the furnace door, and vacuum the furnace body to less than 6×10 ^-3 Pa. At this time, close the vacuum valve and fill the furnace chamber with high-purity argon as a protective gas. Inflate, and pay attention to adjusting the air pressure of the air pressure cavity to be greater than the air pressure of the furnace body cavity. Use high-frequency induction heating to heat the master alloy. After the alloy is melted, pay attention to observe that the color of the solution suddenly changes from orange to yellow-white. Press to connect The pressure chamber is switched on and off, and the high-temperature melt is sprayed onto the rapidly rotating copper roller by the pressure difference to obtain an amorphous alloy strip sample with a thickness of about 22-25 mm and a width of 1.2-1.5 mm.

In another embodiment, in step 2, the thermal characteristic temperature value of the amorphous alloy strip is analyzed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) of the amorphous alloy strip. Sure.

Specifically, the thermal characteristic temperature value includes the initial crystallization temperature (Tx) and the crystallization peak temperature (Tp).

石墨单色器滤波，管电压为40kV，管电流为30mA，测试范围为20～100°，步长0.02°，扫描速度10°/min。若非晶态合金带材XRD衍射谱有且只有一个宽泛的衍射峰(即“馒头峰”)，可确定合金薄带为完全非晶态结构。Specifically, X-ray diffraction analysis (XRD) and differential scanning calorimetry (DSC) analysis include: using X-ray diffraction analysis (XRD) to investigate whether the amorphous alloy strip sample has a complete amorphous structure. XRD related test conditions and parameters are: X-ray wavelength

Filtered by a graphite monochromator, the tube voltage is 40kV, the tube current is 30mA, the test range is 20-100°, the step size is 0.02°, and the scanning speed is 10°/min. If the XRD diffraction spectrum of the amorphous alloy ribbon has one and only one broad diffraction peak (ie "steamed bread peak"), it can be determined that the alloy ribbon has a completely amorphous structure.

A differential scanning calorimeter (DSC) was used to conduct thermal analysis on the crystallization behavior of the amorphous alloy strip samples, and the crystallization characteristics of the alloy strips with continuous heating were investigated. During the test, the alloy strip sample was cut into small pieces with an area of less than 1mmx1mm, weighed about 5-10mg, and put into an alumina crucible. The sample was heated under the protection of N2 atmosphere, and the heating rate was 20℃/ min, the heating range is 50～900℃. According to the DSC curve, the thermal characteristic temperature values such as the initial crystallization temperature (Tx) and the crystallization peak temperature (Tp) of the amorphous alloy strip sample are obtained.

In another embodiment, in step 2, the time of the annealing heat treatment is 3-30 min.

The third aspect of the present application discloses the application of the manganese-based nanocrystalline/amorphous composite structure alloy or the manganese-based nanocrystalline/amorphous composite structure alloy prepared by the preparation method in the preparation of magnetic skyrmion materials.

Specifically, Mn is a metal element with peculiar structure and magnetism among the transition metal elements. There are four allotropes in its solid state. According to Hund's rule, the magnetic moment of Mn atoms can be as high as _5μB , and in the alloy, various magnetic interaction forms of ferromagnetism, antiferromagnetism or ferrimagnetism can be formed according to the distance between adjacent atoms, showing rich and varied physical properties. nature. Manganese-based nanocrystalline/amorphous composite structural materials can be used as skyrmion magnetic structural materials that are stable in a wide temperature range and zero magnetic field.

Specifically, the amorphous alloy strip samples are put into a heat treatment furnace for crystallization annealing heat treatment. The heat treatment equipment is a programmable control single vacuum tube high temperature sintering furnace produced by Nobadi Material Technology Co., Ltd. The model of the furnace is NBD -O1200-60IT. During the heat treatment, heat to the crystallization annealing temperature Ta at a heating rate of 20 °C/min, the holding time is 10 min, and the furnace is cooled to room temperature. In order to avoid oxidation, the entire heat treatment is carried out in a vacuum.

In this application, amorphous alloy strips are prepared by specific treatment through a variety of specific element ratios, and then the amorphous alloy strips appear multi-level crystallization behavior during heating and crystallization, and are further crystallized by heat treatment and annealing to make The nanocrystalline particles of manganese are precipitated on the amorphous alloy matrix to form a manganese-based nanocrystalline/amorphous composite structure alloy; the manganese-based nanocrystalline/amorphous composite structure alloy of the present application requires a certain ratio of elements, or the synergy of multiple elements effect is realized.

The preparation method of the present application is an amorphous alloy strip prepared by induction heating a uniformly mixed master alloy ingot by a copper roll rapid quenching method, the molten alloy liquid needs to have certain fluidity requirements, and the Si content is required to be greater than 10at. %, and further through crystallization annealing treatment, manganese nanocrystalline particles are precipitated on the amorphous matrix to form a manganese-based nanocrystalline/amorphous composite structure alloy. The manganese-based nanocrystalline/amorphous composite structure alloy of the present application has the following outstanding advantages : Using the industrially mature melt quick quenching method to prepare amorphous alloy strips, it has the outstanding advantages of flexibility and high production efficiency. Compared with the amorphous alloy films or powders prepared by the magnetron sputtering method and the mechanical ball milling method, the amorphous alloy strip prepared by the melt rapid quenching method has a simple process, high production efficiency, and is green and pollution-free.

Description of drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that are required to be used in the description of the embodiments or the prior art.

Fig. 1 is the XRD spectrum of the amorphous alloy strip of Mn ₆₈ Si ₂₅ B ₇ provided by the embodiment of the application;

Fig. 2 is the DSC curve of the amorphous alloy strip of Mn ₆₈ Si ₂₅ B ₇ provided in the embodiment of the present application;

Fig. 3 is the XRD spectrum after annealing treatment of the amorphous alloy strip of Mn ₆₈ Si ₂₅ B ₇ provided in the embodiment of the application;

Fig. 4 is the temperature and magnetization of the Mn ₆₈ Si ₂₅ B ₇ amorphous alloy strips provided in the embodiments of the present application in the fast quenched state (amorphous structure) and the annealed state (Mn ₅ Si ₃ nanocrystalline/amorphous composite structure) Relationship lines;

Fig. 5 is the XRD spectrum of the Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ amorphous alloy strip samples provided by the embodiments of the application under rapid quenching;

FIG. 6 is the DSC curve of the Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ amorphous alloy strip samples under rapid quenching provided in the embodiment of the present application;

FIG. 7 is the XRD spectrum of the annealed sample of the nanocrystalline/amorphous composite structure of Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ in the annealed state provided by the embodiment of the present application;

Fig. 8 is the XRD spectrum of the Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (EM is one of Nb, Zr or V) amorphous alloy strip sample under rapid quenching provided by the embodiment of the application;

9 is a DSC curve of an amorphous alloy strip of Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (EM is one of Nb, Zr or V) under rapid quenching provided by the embodiment of the application;

FIG. 10 is the XRD spectrum of the nanocrystalline/amorphous composite structure of Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (EM=Nb, Zr) in the annealed state provided by the embodiment of the application;

FIG. 11 is the XRD spectrum of the rapidly quenched alloy strip sample with Si atomic molar percentage less than 10 at. % provided by the comparative example of the application;

FIG. 12 is the XRD spectrum of the rapidly quenched alloy strip sample with Si atomic molar percentage greater than or equal to 30 at. % provided for the comparative example of the present application.

Detailed ways

The present application provides a manganese-based nanocrystalline/amorphous composite structure alloy and a preparation method thereof, and provides the possibility of a stable skyrmion magnetic structure material in a wide temperature range and a zero magnetic field.

The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

Wherein, the reagents or raw materials used in the following examples are commercially available or homemade.

Example 1

The embodiments of the present application provide a nanocrystalline/amorphous composite structure of Mn ₆₈ Si ₂₅ B ₇ , and the specific steps include:

1. Calculate the atomic molar distribution ratio of each element of the Mn ₆₈ Si ₂₅ B ₇ component, calculate the weight percent distribution ratio of conversion into atoms, and prepare the raw materials required for a 10g master alloy ingot: Mn is 8.2767g, Si is 1.5556g , B is 0.1676g.

2. Put the above raw materials into a vacuum arc melting furnace for arc melting, the melting current is preferably 80A, and the alloy ingot is repeatedly turned over for 4 times of melting to ensure that the composition of the mother alloy ingot is uniform.

3. Break the master alloy into small alloy blocks with a diameter of about 5 to 8 mm, put them into a quartz tube, and use an induction melt rapid quenching strip machine to prepare Mn ₆₈ Si ₂₅ B ₇ amorphous alloy strips. The process of preparing the amorphous alloy strip is as follows: the height of the quartz nozzle from the copper roller is 0.30mm, the line speed of the copper roller is 50m/s, and the pressure difference of the spray strip is 0.04MPa. When stripping, use supersonic high-frequency induction heating power supply with a frequency of 20kHz to conduct induction heating on the mother alloy block placed in a quartz tube, the heating current is 20A, and the holding time to be heated is about 60s. At this time, the alloy block has been completely melted. Then press the spray button, use the pressure difference between the quartz tube and the furnace body to press the alloy liquid out of the quartz tube nozzle, spray it onto the rapidly rotating copper roller, and use the rapid cooling of the copper roller to solidify into a non-ferrous alloy. Crystalline alloy strip.

4. The amorphous alloy strip prepared in step 3 is characterized by XRD. As shown in Figure 1, its XRD pattern only has a broad diffraction peak at the diffraction angle 2θ=45°, that is, the "steamed bread peak", indicating that the The sample is an amorphous alloy strip sample with an amorphous structure under rapid quenching.

5. Perform DSC thermal analysis on the amorphous alloy strip prepared in step 3. As shown in Figure 2, there are two obvious exothermic peaks on the DSC curve of this sample, indicating that the amorphous alloy strip of this embodiment is The crystallization characteristic of the crystallization is double-level crystallization behavior. Combined with XRD phase analysis, it can be seen that the phase corresponding to the first-level crystallization peak is Mn ₅ Si ₃ , and the phase corresponding to the second-level crystallization peak is Mn ₂ B .

6. Based on the crystallization characteristic temperature obtained by the thermal analysis in step 5, it can guide the formulation of the heat treatment annealing process. Obtain Mn ₆₈ Si ₂₅ B ₇ .

The XRD spectrum of the amorphous alloy strip in step 3 after annealing is shown in Figure 3. Only the diffraction peak of Mn ₅ Si ₃ is detected on the XRD spectrum, indicating that after annealing, the sample is in the amorphous phase (non-crystalline phase). Crystal phase: refers to the disordered and uniformly distributed matrix parent phase of Mn, Si and B) only a single Mn ₅ Si ₃ nanocrystalline particle is precipitated on the matrix, and the manganese-based nanocrystalline/amorphous composite has been successfully realized Structural alloy—Mn ₅ Si ₃ nanocrystalline/amorphous dual-phase composite structure (ie, Mn ₆₈ Si ₂₅ B ₇ ).

FIG. 4 is a graph showing the relationship between temperature and magnetization of amorphous alloy strips in a rapidly quenched state (amorphous structure) and an annealed state (Mn ₅ Si ₃ nanocrystalline/amorphous composite structure). The analysis of the magnetization curve shows that the amorphous alloy strip in step 3 exhibits spin-glass transition behavior in both the fast quenched state (amorphous structure) and the annealed state (Mn ₅ Si ₃ nanocrystalline/amorphous composite structure). , the corresponding spin glass transition temperatures (Tf) are 23K and 15K, respectively. The difference is that the amorphous structure sample enters the paramagnetic state after spin glass transition, while the Mn ₅ Si ₃ nanocrystalline/amorphous composite structure sample (Mn ₆₈ Si ₂₅ B ₇ ) first enters the paramagnetic state after spin glass transition. Entering the ferromagnetic state (temperature range from 15K to 100K), and then entering the paramagnetic state, it can be seen that this Mn ₅ Si ₃ nanocrystalline/amorphous dual-phase composite structure (Mn ₆₈ Si ₂₅ B ₇ ) has more obvious self- Gyroscopic glass transition properties, richer magnetic transition behavior.

Example 2

The embodiments of the present application provide nanocrystalline/amorphous composite structures of Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ , and the specific steps include:

1. Calculate the atomic molar ratio of each element in the components of Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ and convert them into atomic weight percent ratios to prepare 10g of Mn ₆₄ Raw materials required for the Si ₂₅ B ₇ Ag ₁ Nb ₃ master alloy ingot: Mn 7.6237 g, Si 1.4328 g, B 0.1544 g, Ag 0.2201 g, and Nb 0.5687 g. Raw materials required to prepare 10 g of _{Mn64Si25B7Cu1Nb3} master alloy ingot: Mn _7.6933 g, Si _1.4459 g, B _0.1558 g, Cu 0.1308 g, Nb _0.5687 g.

2. Put the above raw materials into a vacuum arc melting furnace for arc melting, the melting current is preferably 80A, and the alloy ingot is repeatedly turned over for 4 times of melting to ensure that the composition of the mother alloy ingot is uniform.

3. Break the master alloy into small alloy blocks with a diameter of about 5 to 8 mm, put them into a quartz tube, and use an induction melt fast quenching strip machine to prepare Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ amorphous alloy strip. The process of preparing the amorphous alloy strip is as follows: the height of the quartz nozzle from the copper roller is 0.25mm, the linear speed of the copper roller is 55m/s, and the pressure difference of the spraying strip is 0.06MPa. When the belt is spun, a supersonic high-frequency induction heating power supply with a frequency of 20kHz is used to inductively heat the mother alloy ingot in the quartz tube. The heating current is 30A, and the heating holding time is about 100s. When the liquid flows well, press the spray button at this time, use the pressure difference between the quartz tube and the furnace body to press the alloy liquid out of the quartz tube nozzle, spray it onto the rapidly rotating copper roller, and use the rapid cooling of the copper roller to solidify into two Amorphous alloy strip.

4. The two samples of amorphous alloy strips prepared in step 3 under rapid quenching were characterized by XRD. As shown in Figure 5, their XRD patterns only showed a broad diffraction peak at the diffraction angle 2θ=45°. That is, the "steamed bread peak", which indicates that the two amorphous alloy strip samples are both amorphous structures under rapid quenching.

5. Perform DSC thermal analysis on two amorphous alloy strip samples respectively. As shown in Figure 6, there are three exothermic peaks on the DSC curves of the two amorphous alloy strip samples under rapid quenching, indicating that the two The crystallization characteristics of the crystalline alloy strip samples are multi-level crystallization behavior. Combined with the phase analysis of XRD, it can be seen that the first and second-order crystallization peaks that overlap in the adjacent parts correspond to the precipitated phases of Mn ₃ Si and Mn ₅ Si ₃ . The precipitated phase corresponding to the third-order crystallization peak is Mn ₂ B.

6. Based on the crystallization characteristic temperatures of the two amorphous alloy strip samples obtained respectively by the thermal analysis in step 5, the two amorphous alloy strip samples were placed in a vacuum tube furnace for annealing and heat preservation at 580° C. for 10 minutes, respectively. Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ nanocrystalline/amorphous composite structure were obtained.

Fig. 7 is the XRD spectrum of the nanocrystalline/amorphous composite structure of Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ and Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ in the above annealed state. ₃ Si and Mn ₅ Si ₃ , indicating that after the retrograde crystallization treatment, the two samples are in the amorphous phase (amorphous phase: refers to the disordered and uniformly distributed matrix parent phase of Mn, Si, B, Ag and Nb) ) two kinds of manganese-silicon compounds, namely Mn ₃ Si and Mn ₅ Si ₃ nanocrystalline particles, were precipitated on the matrix, and the manganese-based nanocrystalline/amorphous composite structure of Mn ₃ Si and Mn ₅ Si ₃ dual-phase nanocrystalline/amorphous composite structure was successfully realized. Preparation of Amorphous Multiphase Composite Microstructures.

Example 3

The embodiments of the present application provide a nanocrystalline/amorphous composite structure of Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₃ , Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Zr ₃ or Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ V ₃ , and the specific steps include: :

1. The formula component is Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (EM=Nb, Zr, V). The atomic molar ratio of each element of Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₃ is calculated and converted into the atomic weight percentage ratio, and the raw materials required to prepare a 10g master alloy ingot: Mn is 6.3274g, Fe is 1.7542g, B is 0.1584g, Nb is 0.5836g; similarly, for the nanocrystalline/amorphous composite structure sample with EM=Zr, V, the raw material dosage is calculated according to the corresponding atomic percentage.

2. Put the above raw materials into the vacuum arc melting furnace for arc melting, the melting current is preferably 100A, and the alloy ingot is repeatedly turned over for 4 times of melting to ensure that the composition of the mother alloy ingot is uniform.

3. Break the master alloy into small alloy blocks with a diameter of about 5 to 8 mm respectively, put them into a quartz tube and prepare Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (EM=Nb, Zr,V) amorphous alloy strip. The strip preparation process is as follows: the height of the quartz nozzle from the copper roll is 0.25mm, the line speed of the copper roll is 55m/s, and the pressure difference of the spray strip is 0.06MPa. When the belt is spun, a supersonic high-frequency induction heating power supply with a frequency of 20kHz is used to inductively heat the mother alloy ingot in the quartz tube. The heating current is 30A, and the heating holding time is about 100s. When the liquid flows well, press the spray button at this time, use the pressure difference between the quartz tube and the furnace body to press the alloy liquid out of the quartz tube nozzle, spray it onto the rapidly rotating copper roller, and use the rapid cooling of the copper roller to solidify into amorphous Alloy strip samples.

4. The Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (EM=Nb, Zr, V) amorphous alloy strip samples prepared in step 3 under rapid quenching were characterized by XRD, as shown in FIG. 8 , their XRD patterns There is only one broad diffraction peak at the diffraction angle 2θ=45°, that is, the "steamed bread peak", which indicates that the sample is an amorphous alloy strip sample with an amorphous structure under rapid quenching.

5. Perform DSC thermal analysis on the Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (EM=Nb, Zr, V) amorphous alloy strip samples in step 3 respectively, and the curves are shown in Figure 9. The DSC curves of all samples have Two obvious exothermic peaks indicate that the crystallization of the amorphous sample is characterized by secondary crystallization behavior. Combined with the XRD phase analysis, it can be seen that the first-order crystallization peaks correspond to the precipitated phases of α-Mn and Mn ₆ Si, and the first-order crystallization peaks correspond to the precipitated phases. The secondary crystallization peak corresponds to the precipitated phase of Mn ₂ B.

6. Based on the crystallization characteristic temperature obtained by the thermal analysis in step 5, the Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Zr ₃ amorphous alloy strip sample is subjected to annealing treatment at 600° C. for 10 minutes, and the Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₃ amorphous alloy strip samples were annealed at 620 ℃ for 10 min to obtain Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Zr ₃ and Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₃ nanocrystalline/amorphous composite microstructures .

10 is the XRD spectrum of the nanocrystalline/amorphous composite structure of Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Zr ₃ and Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ Nb ₃ in the annealed state of the embodiment of the present application, and it can be seen from the analysis of the spectrum , after the annealing of the amorphous alloy strip sample, two kinds of manganese are precipitated on the matrix of the amorphous phase (amorphous phase: refers to the disordered and uniformly distributed matrix parent phase of Mn, Fe, Si, B and Nb) Silicon compounds, namely α-Mn and Mn ₆ Si nanocrystalline particles, successfully prepared a manganese-based nanocrystalline/amorphous composite structure alloy of α-Mn and Mn ₆ Si dual-phase nanocrystalline/amorphous composite structure type.

Comparative Example 1

The comparative examples of the present application provide manganese-based alloys with different Si contents, and the specific methods include:

Referring to the method of Example 1, the difference in this comparative example is that the atomic mole number of Si is less than 10, and the mole number of Si is greater than or equal to 30, that is, according to Mn ₈₃ Si ₄ B ₁₃ , Mn ₈₂ Si ₆ B ₁₂ , Mn ₈₂ Si ₈ B ₁₀ , Mn ₄₅ Si ₄₅ B ₁₀ , Mn ₆₃ Si ₃₀ B ₇ atomic molar ratio of each element, with reference to the method of step 2 and step 3 of Example 1, to prepare manganese-based alloy strips with different Si contents, that is, to obtain Mn ₈₃ Si ₄ B ₁₃ alloy strip, Mn ₈₂ Si ₆ B ₁₂ alloy strip, Mn ₈₂ Si ₈ B ₁₀ alloy strip, Mn ₄₅ Si ₄₅ B ₁₀ alloy strip, Mn ₆₃ Si ₃₀ B ₇ alloy strip, The above alloy strips are not subjected to annealing heat treatment, but only to rapid melt quenching treatment.

The XRD spectrum analysis of the alloy strip in the above-mentioned rapid quenching state is carried out, and the results are shown in FIGS. 11 to 12 . Figure 11 shows the XRD spectrum of the rapidly quenched alloy strip with Si atomic molar percentage less than 10 at.%. It can be seen from the figure that the alloy strip in the rapidly quenched state has appeared serious crystallization peaks, and it is difficult to prepare under the existing conditions. The amorphous alloy strip with amorphous structure is obtained; Figure 2 shows the XRD spectrum of the rapidly quenched alloy strip with Si atomic molar percentage greater than or equal to 30 at.%. The sample in the rapid quench state also undergoes severe crystallization. It can be seen that an amorphous ribbon with an amorphous structure cannot be obtained by the copper roll rapid quenching method.

To sum up, in the embodiments of the present application, one or two elements of α-Mn, Mn ₅ Si ₃ , Mn ₃ Si and Mn ₆ Si are precipitated on the amorphous alloy matrix by annealing and crystallization of the amorphous alloy precursor. Or manganese-silicon compound nanoparticles to form manganese-based nanocrystalline/amorphous composite structural materials. The important thing is that through the composition design of the manganese-based nanocrystalline/amorphous composite structure alloy, the amorphous alloy has multi-level crystallization in the thermal analysis of crystallization, and the first-level crystallization corresponds to the precipitation of manganese element or manganese silicon. compound, which can control the precipitation of nanocrystalline particles through heat treatment, and realize the controllable preparation of manganese-based nanocrystalline/amorphous composite structure alloys. For the Mn-Si-B ternary amorphous alloy, when the Si atomic molar percentage is 10-20 at.%, Mn-Si-B is single-stage crystallization (there is only one exothermic peak on the DSC curve). To moderately adjust the ratio of Si/B and Si/Mn, the amorphous sample will exhibit multi-level crystallization behavior. For example, the sample of Example 1 has 25 at.% Si, and DSC has two exothermic peaks, corresponding to the precipitation of Mn ₅ Si ₃ and Mn ₂ B phase. In addition, the nucleation of Mn or manganese compounds is promoted by introducing elements that are insoluble in Mn, such as Cu and Ag, and the precipitation of Mn ₂ B phase is delayed by the addition of large atoms such as Nb, and the temperature interval of crystallization peaks is enlarged, which is more conducive to the precipitation of heat treatment. Manganese silicon nanoparticles (Example 2). In addition, an appropriate amount of Fe, Co, and Ni can be introduced to form the synergistic effect of nucleation centers and large atoms such as Zr and Nb, so as to control the crystallization behavior of amorphous alloys and precipitate phases. For example, the synergistic effect of Fe and Zr, Nb or V in the composition formula of Example 3 makes the amorphous alloy appear bi-level crystallization behavior. The multi-level crystallization behavior of amorphous alloys can be controlled to prepare manganese-based nanocrystalline/amorphous composite structural materials.

In addition, the manganese-based nanocrystalline/amorphous composite structure alloys prepared in the examples of the present application endow the materials with more excellent properties and richer magnetic transition phenomena. Among the materials of Example 1, Figure 4 discloses the magnetic performance of the manganese-based nanocrystalline/amorphous composite structure alloy sample and the amorphous sample of this embodiment. Obviously, the manganese-based nanocrystalline/amorphous composite structure alloy of this embodiment is The samples have unusual amorphous alloy magnetic transition properties and richer magnetic transition behaviors. The manganese-based nanocrystalline/amorphous composite structure alloy of the present application provides the possibility to develop skyrmion magnetic structure materials with wide temperature range and zero magnetic field stability, and has academic research value and potential practical application in the field of spintronics value.

The above are only the preferred embodiments of the present application. It should be pointed out that for those skilled in the art, without departing from the principles of the present application, several improvements and modifications can also be made. It should be regarded as the protection scope of this application.

Claims (8)

1. The manganese-based nanocrystalline/amorphous composite structural alloy is characterized by having the following general formula:

Mn _bal Si _a B _b M _c R _d T _e ；

in the general formula, Mn _bal The alloy system takes Mn as a main component, and the atomic mole number bal of the alloy system is more than or equal to 55; the mole number a of the Si element satisfies a condition that a is not less than 10<30, of a nitrogen-containing gas; the mole number B of the B element satisfies 5<b is less than or equal to 12; m is selected from one or more of Fe, Co, Ni and Cr elements, and the atomic mole number c satisfies 0-25; r is selected from one or more of Ag, Mg and Cu elements, and the atomic mole number d of the R is more than or equal to 0 and less than or equal to 5; t is selected from one or more of Zr, Ti, V, Nb, Hf and Ta, and the atomic number e is more than or equal to 0 and less than or equal to 8; the atomic mole number of the sum of bal + a + b + c + d + e is 100;

step 1, mixing raw materials of a manganese-based nanocrystalline/amorphous composite structure alloy according to the proportion of the manganese-based nanocrystalline/amorphous composite structure alloy, and then performing melt rapid quenching to obtain an amorphous alloy strip;

step 2, annealing heat treatment is carried out on the amorphous alloy strip according to the thermal characteristic temperature value of the amorphous alloy strip, so as to prepare the manganese-based nanocrystalline/amorphous composite structure alloy;

the thickness of the amorphous alloy strip is 22-25 mm; the width of the amorphous alloy strip is 1.2-1.5 mm;

in the step 2, the annealing heat treatment time is 3-30 min.

2. The manganese-based nanocrystalline/amorphous composite structural alloy according to claim 1, wherein in the general formula, M is selected from Fe.

3. The manganese-based nanocrystalline/amorphous composite structural alloy according to claim 1, wherein in the general formula, R is selected from Ag or Cu.

4. The manganese-based nanocrystalline/amorphous composite structural alloy according to claim 1, wherein in the general formula, T is one selected from Nb, Zr, and V.

5. The manganese-based nanocrystalline/amorphous composite structural alloy according to claim 1, wherein the manganese-based nanocrystalline/amorphous composite structural alloy has a chemical formula of: mn ₆₈ Si ₂₅ B ₇ 、Mn ₆₄ Si ₂₅ B ₇ Ag ₁ Nb ₃ 、Mn ₆₄ Si ₂₅ B ₇ Cu ₁ Nb ₃ Or Mn ₅₅ Fe ₁₅ Si ₂₀ B ₇ EM ₃ (ii) a Wherein EM is one or more of Nb, Zr and V.

6. A preparation method of a manganese-based nanocrystalline/amorphous composite structure alloy is characterized by comprising the following steps:

step 1, mixing the raw materials of the manganese-based nanocrystalline/amorphous composite structural alloy according to the proportion of the manganese-based nanocrystalline/amorphous composite structural alloy in any one of claims 1 to 5, and then performing melt rapid quenching to obtain an amorphous alloy strip;

step 2, annealing heat treatment is carried out on the amorphous alloy strip according to the thermal characteristic temperature value of the amorphous alloy strip, so as to prepare the manganese-based nanocrystalline/amorphous composite structure alloy;

the thickness of the amorphous alloy strip is 22-25 mm; the width of the amorphous alloy strip is 1.2-1.5 mm;

in the step 2, the annealing heat treatment time is 3-30 min.

7. The production method according to claim 6, wherein in step 1, the treatment is an arc melting treatment or a magnetron sputtering treatment.

8. The method according to claim 6, wherein in step 2, the thermal characteristic temperature value of the amorphous alloy strip is determined by X-ray diffraction analysis and differential scanning calorimetry analysis of the amorphous alloy strip.

Images