阅读说明：本技术 一种NiMn掺杂的CoFe基多晶软磁合金及其制备方法 (NiMn-doped CoFe-based polycrystalline soft magnetic alloy and preparation method thereof ) 是由 聂志华 金昊 谭成文 于晓东 宁先进 刘影夏 赵修臣 于 2019-11-14 设计创作，主要内容包括：本发明涉及一种NiMn掺杂的CoFe基多晶软磁合金及其制备方法,属于磁性材料技术领域。本发明通过在Co<Sub>70</Sub>Fe<Sub>30</Sub>合金中加入NiMn合金基团,在保持了Co<Sub>70</Sub>Fe<Sub>30</Sub>合金本身优异的合金软磁性能、磁致伸缩性能、低廉的成本等优势的同时,大大提高了合金的力学性能；另外,制备所述合金的原料成本低廉,制备过程简单便捷,成品率高,绿色环保,不需要使用昂贵的大型仪器设备,可以快速低成本地在工业生产中推广应用。(The invention relates to a NiMn-doped CoFe-based polycrystalline soft magnetic alloy and a preparation method thereof, belonging to the technical field of magnetic materials. The invention is realized by adding Co 70 Fe 30 NiMn alloy group is added into the alloy, and Co is maintained 70 Fe 30 The alloy has the advantages of excellent alloy soft magnetic property, magnetostriction property, low cost and the like, and the mechanical property of the alloy is greatly improved; in addition, the raw materials for preparing the alloy are low in cost, the preparation process is simple and convenient, the rate of finished products is high, the green and environment-friendly effects are achieved, expensive large-scale instruments and equipment are not needed, and the alloy can be rapidly popularized and applied in industrial production at low cost.)

1. A NiMn doped CoFe-based polycrystal soft magnetic alloy is characterized in that: the chemical formula expression of the alloy is expressed as (Co)₇₀Fe₃₀)_100-x(NiMn)_x，x＝2.5～20。

2. The NiMn-doped CoFe-based polycrystalline magnetically soft alloy as claimed in claim 1, wherein: x is more than or equal to 2.5 and less than or equal to 10.

3. The NiMn-doped CoFe-based polycrystalline magnetically soft alloy as claimed in claim 1, wherein: x is more than 10 and less than or equal to 20.

4. A method of producing a NiMn-doped CoFe-based polycrystalline soft magnetic alloy as claimed in any one of claims 1 to 3, wherein: the steps of the method are as follows,

step 1, mixing Ni and Mn according to an atomic ratio of 1:1, and smelting under a vacuum condition to obtain a NiMn alloy ingot;

step 2, according to (30-0.3 x): (70-0.7 x): and x, putting Fe, Co and NiMn alloy ingots into a crucible of a high vacuum arc melting furnace according to the atomic ratio, and then melting to obtain the alloy.

5. The method of claim 4, wherein the NiMn-doped CoFe-based polycrystalline magnetically soft alloy comprises the following steps: fe, Co, Ni and Mn with the purity of more than 99.9 percent are selected as raw materials, oxide skin on the surface of the raw materials is polished clean before use, and the raw materials are ultrasonically cleaned in an acetone solution and finally dried for later use.

6. The method of claim 4, wherein the NiMn-doped CoFe-based polycrystalline magnetically soft alloy comprises the following steps: the NiMn alloy ingot is prepared by smelting in a high vacuum induction smelting furnace, the specific operation is as follows,

firstly, the high vacuum induction melting furnace is vacuumized to 2 multiplied by 10^-2And introducing argon until the pressure in the furnace reaches 0.05-0.06 MPa, completely melting the metal raw materials to molten metal, pouring the molten metal into a mold, and cooling and solidifying to obtain the NiMn alloy ingot.

7. The method of claim 4, wherein the NiMn-doped CoFe-based polycrystalline magnetically soft alloy comprises the following steps: the specific operation of smelting by using the high vacuum arc smelting furnace is as follows,

firstly, the high vacuum arc melting furnace is vacuumized to 2.5 multiplied by 10^-3And introducing argon under Pa until the pressure in the furnace reaches 0.05-0.06 MPa, repeatedly smelting for 3-5 times under the smelting current of 2-4A, wherein the time of each smelting is 4-6 min, and stirring during the other smelting except the first smelting and the last smelting.

Technical Field

The invention relates to a NiMn-doped CoFe-based polycrystalline soft magnetic alloy and a preparation method thereof, belonging to the technical field of magnetic materials.

Background

The CoFe-based soft magnetic alloy, also called Permendur, has important application prospect in the fields of sensors, transducers, micro-displacement driving, noise reduction, vibration reduction, intelligent robots, fuel injection, wave oil extraction and the like due to the advantages of stable magnetic susceptibility, extremely high magnetic conductivity, excellent magnetostriction performance, excellent energy absorption performance and low cost.

However, the poor mechanical properties of the CoFe-based soft magnetic alloy also limit the application of the CoFe-based soft magnetic alloy in many engineering application fields. Therefore, it is necessary to develop a new series of CoFe-based soft magnetic alloys having excellent mechanical properties while maintaining the excellent properties of the CoFe-based soft magnetic alloys themselves.

Disclosure of Invention

In view of the shortcomings of the prior art, it is an object of the present invention to provide a NiMn-doped CoFe-based polycrystalline soft magnetic alloy prepared by adding Co into a Co-based alloy₇₀Fe₃₀NiMn alloy group is added into the alloy, and Co is maintained₇₀Fe₃₀The alloy has the advantages of excellent alloy soft magnetic property, magnetostriction property, low cost and the like, and the mechanical property of the alloy is greatly improved;

the invention also aims to provide a preparation method of the NiMn-doped CoFe-based polycrystalline soft magnetic alloy, which has the advantages of simple and convenient process, high yield, environmental protection, no need of expensive large-scale instruments and equipment, and rapid popularization and application in industrial production at low cost.

The purpose of the invention is realized by the following technical scheme.

A CoFe-based polycrystal soft magnetic alloy doped with NiMn, the chemical formula expression of the alloy is expressed as (Co)₇₀Fe₃₀)_100-x(NiMn)_x，x＝2.5～20。

Wherein, when x is more than or equal to 2.5 and less than or equal to 10, (Co)₇₀Fe₃₀)_100-x(NiMn)_xThe alloy has high strength, high saturation magnetization and excellent magnetostriction performance; when x is more than 10 and less than or equal to 20, (Co)₇₀Fe₃₀)_100-x(NiMn)_xThe alloy has high elongation and high saturation magnetization.

The preparation method of the NiMn doped CoFe-based polycrystalline magnetically soft alloy comprises the following steps:

step 1, mixing Ni and Mn according to an atomic ratio of 1:1, and smelting under a vacuum condition to obtain a NiMn alloy ingot;

step 2, according to (30-0.3 x): (70-0.7 x): and x, putting Fe, Co and NiMn alloy ingots into a crucible of a high vacuum arc melting furnace according to the atomic ratio, and then melting to obtain the alloy.

Further, Fe, Co, Ni and Mn with the purity of more than 99.9 percent are selected as raw materials; in addition, before use, the oxide skin on the surface of the material is polished, then the material is ultrasonically cleaned in an acetone solution, and finally the material is dried for later use.

Further, a high vacuum induction smelting furnace is adopted to smelt and prepare the NiMn alloy ingot, and the specific operation is as follows: firstly, the high vacuum induction melting furnace is vacuumized to 2 multiplied by 10^-2And introducing argon under Pa until the pressure in the furnace reaches 0.05-0.06 MPa, smelting pure nickel and pure manganese into molten metal by utilizing induction heating, and pouring the molten metal into a mold for cooling and solidifying after the metal raw materials are completely molten to obtain the NiMn alloy ingot.

Further, the specific operation of smelting by using the high vacuum arc smelting furnace is as follows: firstly, the high vacuum arc melting furnace is vacuumized to 2.5 multiplied by 10^-3And introducing argon under Pa until the pressure in the furnace reaches 0.05-0.06 MPa, repeatedly smelting for 3-5 times under the smelting current of 2-4A, wherein the time of each smelting is 4-6 min, and stirring during the other smelting except the first smelting and the last smelting.

Has the advantages that:

(1) (Co) according to the invention₇₀Fe₃₀)_100-x(NiMn)_xAlloy (I)In the presence of Co₇₀Fe₃₀The alloy has the advantages of excellent soft magnetic property and magnetostriction property, low cost and the like, and also has excellent mechanical property, particularly when x is more than or equal to 2.5 and less than or equal to 10, the alloy has extremely high strength, the elongation is greatly improved compared with other CoFe-based soft magnetic alloys, the requirement on service environment is lower, and the service time is longer; when x is more than 10 and less than or equal to 20, the alloy has extremely high elongation, and has great advantages when deformation processing such as drawing, cold rolling and the like is required to be carried out on the alloy compared with other CoFe-based soft magnetic alloys;

(2) (Co) according to the invention₇₀Fe₃₀)_100-x(NiMn)_xThe alloy has the advantages of low cost of selected raw materials, simple and convenient preparation process, low defect rate, high yield and no pollution in the preparation process.

Drawings

FIG. 1 shows (Co) prepared in examples 1 to 5₇₀Fe₃₀)_100-x(NiMn)_xAlloy and Co prepared in comparative example 1₇₀Fe₃₀The true stress-strain curve of the alloy is compared.

FIG. 2 shows (Co) prepared in examples 1 to 4₇₀Fe₃₀)_100-x(NiMn)_xAlloy and Co prepared in comparative example 1₇₀Fe₃₀The magnetostriction curves of the alloy along the magnetic field direction are compared with each other.

FIG. 3 shows (Co) prepared in examples 1 to 5₇₀Fe₃₀)_100-x(NiMn)_xAlloy and Co prepared in comparative example 1₇₀Fe₃₀Magnetization curves of the alloys are compared.

FIG. 4 is (Co) prepared in example 1₇₀Fe₃₀)_97.5(NiMn)_2.5Transmission electron microscopy diffraction speckle patterns of the alloys.

FIG. 5 shows Co prepared in comparative example 1₇₀Fe₃₀Inverse pole figure (IPF figure) of the alloy.

FIG. 6 is (Co) prepared in example 1₇₀Fe₃₀)_97.5(NiMn)_2.5IPF diagram of alloy.

Detailed Description

The invention is further illustrated by the following figures and detailed description, wherein the process is conventional unless otherwise specified, and the starting materials are commercially available from a public disclosure without further specification.

The information on the main reagents and the information on the main instruments and equipments mentioned in the following examples are shown in Table 1 and Table 2, respectively.

TABLE 1

TABLE 2

(Co) prepared in the examples was tested by strain gauge resistance measurement₇₀Fe₃₀)_100-x(NiMn)_xAlloy and Co₇₀Fe₃₀The magnetostriction coefficient of the alloy is that a test sample is in a flat plate shape of 8mm multiplied by 6mm multiplied by 2mm, and the specific test steps are as follows:

(1) selecting a determined direction, and pasting a resistance strain gauge on the samples with the same testing surface and direction;

(2) connecting a sample and a strain gauge into a current loop, placing the current loop in the central area of an electromagnet, installing a gauss meter on the position 1mm above the surface of the sample, setting a magnetic field from 0Oe to 5000Oe, from 5000Oe to-5000 Oe, from-5000 Oe to 0Oe, and communicating a power supply to start testing;

(3) in the process of magnetic field change, the length of the block sample changes to cause the length of the resistance strain gauge to change, so that the resistance of the strain gauge changes, the strain gauge measures the resistance change of the strain gauge, and the deformation quantity of the sample, namely the size of the magnetostrictive strain value, is obtained through conversion of computer software.

(Co) prepared in the examples was tested using an electronic Universal Material tester₇₀Fe₃₀)_100-x(NiMn)_xAlloy and Co₇₀Fe₃₀Mechanical properties of the alloyThe test sample is flat, the gauge length is 10mm, the section size is 3mm multiplied by 1mm, and the specific test steps are as follows:

(1) installing a tensile sample on a tensile fixture, installing a fixture joint at a corresponding interface of an electronic universal material testing machine, and drawing a point at each of two ends of a sample gauge length as a mark;

(2) pre-tightening the sample, positioning the video extensometer gauge length, and setting the stretching speed to be 0.01 mm/s;

(3) and starting a tensile test after zero setting, ending the test after the sample is broken, and obtaining the data recorded by the computer as the mechanical property data of the measured material.