Cu-Ni-Sn-Mn-B magnetic copper alloy and preparation method thereof

Abstract

The invention discloses a Cu-Ni-Sn-Mn-B magnetic copper alloy and a preparation method thereof, belongs to the technical field of magnetic non-ferrous metals, and solves the technical problem of insufficient performance of Cu-Ni-Sn alloys, and the solution is as follows: the chemical formula of the magnetic copper alloy is CuyNi15Sn8MnxB0.1. The preparation method comprises the following steps: firstly, weighing raw materials and carrying out vacuum arc melting to prepare a magnetic copper alloy ingot; secondly, the magnetic copper alloy cast ingot is annealed for the first time; thirdly, rolling the magnetic copper alloy cast ingot subjected to primary annealing, and performing secondary annealing after rolling; and finally, the magnetic copper alloy ingot obtained after secondary annealing is thrown out of a thin strip through a melt-spinning machine, the magnetic copper alloy thin strip is fed into a vacuum annealing furnace to be subjected to tertiary annealing, and the Cu-Ni-Sn-Mn-B magnetic copper alloy thin strip is obtained. The prepared magnetic copper alloy has good magnetic performance, appropriate Curie temperature, no toxicity and good heat conduction performance.

Description

Technical Field

[0001] The invention belongs to the technical field of magnetic nonferrous metals, and specifically relates to a Cu-Ni-Sn-Mn-B magnetic copper alloy and a preparation method thereof. Background Art

[0002] Beryllium bronze alloy has excellent comprehensive properties, excellent wear resistance, relatively high electrical conductivity and heat resistance, and high tensile strength. It can meet most of the use requirements at room temperature, so the alloy is more and more widely used in production and life. However, with the increase in public environmental awareness in recent years, the consideration of the comprehensive performance of the alloy has become higher and higher. Beryllium bronze itself also has some inherent disadvantages, such as: dust and toxic oxides will be generated during the production process; the stress relaxation resistance at high temperature is poor, and the general use temperature is low; the production process is complex and the cost is high. These problems have seriously restricted the further development of beryllium bronze materials. Therefore, in recent years, researchers have been constantly seeking new alloy materials that can replace beryllium bronze materials.

[0003] In the process of searching for Cu-based magnetic alloys with excellent performance, Cu-Ni-Sn alloy has comparable mechanical properties to beryllium copper alloy, and Cu-Ni-Sn alloy removes the beryllium element that produces toxic powder, completely eliminating the harm of beryllium copper alloy to human body and ecology during production and use. Therefore, Cu-Ni-Sn alloy was considered as a potential alternative material to beryllium copper alloy at the beginning of its development. Compared with beryllium bronze, Cu-Ni-Sn alloy has the advantages of low cost, non-toxicity, corrosion resistance, good welding performance and good thermal stability.

[0004] Cu-Ni-Sn alloy is prone to dendrite segregation during the solidification process, resulting in the formation of a coarse dendrite structure inside the alloy. This structure not only affects the mechanical properties of the alloy, but also reduces the stability of its performance. In addition, the alloy exhibits obvious thermal instability in a high temperature environment, resulting in a decrease in its mechanical properties. This characteristic limits its application in high temperature environments. The magnetic permeability of Cu-Ni-Sn alloy is extremely low, and it is difficult to meet the requirements of some magnetic properties. Therefore, it is not suitable for the manufacture of magnetic components with strict magnetic requirements, such as high-performance magnetic cores and permanent magnets. In addition, the resistivity of Cu-15Ni-8Sn alloy is relatively high, and it is not suitable for use as a conductive material. At the same time, its temperature coefficient of resistivity is large, resulting in significant fluctuations in its resistivity when the temperature changes. Summary of the invention

[0005] The main purpose of the present invention is to overcome the deficiencies in the prior art, solve the mechanical property limitations caused by the easy segregation of Cu-Ni-Sn alloy and the application limitations of its almost non-magnetic influence, and improve its performance through trace element doping and heat treatment process. The present invention provides a Cu-Ni-Sn-Mn-B magnetic copper alloy and a preparation method thereof.

[0006] The present invention is achieved through the following technical solutions:

[0007] A Cu-Ni-Sn-Mn-B magnetic copper alloy, wherein the chemical molecular formula of the Cu-Ni-Sn-Mn-B magnetic copper alloy is: Cu y Ni 15 Sn 8 Mn x B 0.1 , where x and y are mass percentages, wherein 0≤x≤22wt%, 56.9wt%≤y≤76.9wt%, and x+y+15wt%+8wt%+0.1wt%=100wt%.

[0008] Cu-Ni-Sn alloy can be made into a material with special properties such as high temperature resistance, corrosion resistance and high resistance by adding one or more trace elements. The present invention studies the influence of doping elements on Cu-10Ni-8Sn alloy and finds that Mn element and B element can enhance the performance of Cu-10Ni-8Sn alloy, wherein:

[0009] The effects of Mn element on Cu-Ni-Sn alloy include:

[0010] (1) Solid solution strengthening: Mn can form solid solutions with copper, nickel and tin. Mn atoms exist in the crystal lattice, which can improve the overall mechanical strength and hardness of the alloy;

[0011] (2) Grain refinement: Mn can promote the grain refinement of Cu-Ni-Sn alloy. Mn element can act as a grain refiner to reduce the grain size of the alloy. A finer grain size can improve the mechanical properties of the alloy, such as strength and ductility.

[0012] (3) Precipitation hardening: Mn can form precipitates or intermetallic compounds with other elements in Cu-Ni-Sn alloys. These precipitates can strengthen the alloy through the precipitation hardening process. The dispersed precipitates hinder the movement of dislocations, thereby increasing strength and hardness.

[0013] (4) Corrosion resistance: Adding Mn can improve the corrosion resistance of Cu-Ni-Sn alloy. The B element can improve the density and hot rolling performance of the alloy and increase its strength;

[0014] The influence of B element on Cu-Ni-Sn alloy is as follows: the atomic radius of B element is smaller than that of Cu, Ni and Sn, but larger than that of interstitial elements C and N, and the vacancy gap at the grain boundary is larger than that inside the crystal, so it is more appropriate to fill B on the grain boundary than inside the crystal, which helps to reduce the grain boundary energy, reduce the vacancies at the grain boundary, reduce diffusion, and thus improve resistance.

[0015] Furthermore, the composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 3wt%-7wt%, B: 0.1wt%, and the balance is copper.

[0016] Furthermore, the composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 8wt%-12wt%, B: 0.1wt%, and the balance is copper.

[0017] Furthermore, the composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 13wt%-17wt%, B: 0.1wt%, and the balance is copper.

[0018] Furthermore, the composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 18wt%-22wt%, B: 0.1wt%, and the balance is copper.

[0019] Furthermore, the room temperature magnetic property of the Cu-Ni-Sn-Mn-B magnetic copper alloy is 15emu / g, the Curie temperature is 360K, the Vickers hardness is 245HV, the minimum coercive force is 9Oe, the residual magnetization is less than 1emu / g, and the resistivity is 1×10 -7 Ω·m.

[0020] Furthermore, the frequency characteristics of the Cu-Ni-Sn-Mn-B magnetic copper alloy at 50Hz, 5kHz, and 10kHz are as follows: the magnetic susceptibility is higher at low frequencies, mainly contributed by the movement of the magnetic domain walls. As the frequency increases, the magnetic susceptibility gradually decreases, and the magnetic domain rotation and eddy current losses become dominant. Material properties and external conditions (temperature, magnetic field) have a significant impact on the frequency characteristics. By regulating the composition and microstructure of the alloy, the frequency characteristics of its AC magnetic susceptibility can be optimized to meet the needs of different applications.

[0021] A method for preparing the Cu-Ni-Sn-Mn-B magnetic copper alloy as described above comprises the following steps:

[0022] Firstly, raw materials are weighed according to the composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy, and a magnetic copper alloy ingot is prepared by vacuum arc melting;

[0023] Secondly, the magnetic copper alloy ingot is placed in a vacuum annealing furnace for the first annealing at a temperature of 800°C for 1.5 hours, and then cooled to room temperature along with the furnace;

[0024] Next, the magnetic copper alloy ingot after the first annealing is rolled with a total reduction of 20%-25%, and then sent to a vacuum annealing furnace for a second annealing at a temperature of 500° C. for 1.5 hours, and then cooled to room temperature with the furnace;

[0025] Finally, the magnetic copper alloy ingot after the second annealing is thrown out into a thin strip through a strip throwing machine, and the magnetic copper alloy thin strip is sent to a vacuum annealing furnace for the third annealing. The third annealing temperature is 500°C, the holding time is 1.5h, and then it is cooled to room temperature with the furnace to obtain a Cu-Ni-Sn-Mn-B magnetic copper alloy thin strip.

[0026] The beneficial effects of the present invention are:

[0027] (1) By adjusting the ratio of alloy components, the Cu-Ni-Sn-Mn-B alloy has good magnetic properties and a suitable Curie temperature;

[0028] (2) After determining the composition of the magnetic alloy, the present invention improves the alloy properties by combining a rolling process with a heat treatment process;

[0029] (3) The raw materials Cu, Ni, Sn, Mn and B required for the magnetic alloy provided by the present invention are low in price, abundant in reserves, non-toxic, and have good thermal conductivity and performance stability;

[0030] (4) The present invention adopts conventional smelting equipment to prepare the alloy, and the process is simple and easy to implement, and is easy to industrialize. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a metallographic micrograph of Cu-Ni-Sn-Mn-B alloy, and the scale bar is 200 microns;

[0032] Figure 2 It is the X-ray diffraction spectrum of Cu-Ni-Sn-Mn-B alloy after annealing;

[0033] Figure 3 The thermomagnetic curve of the magnetization intensity M of the Cu-Ni-Sn-Mn-B alloy after annealing in a 1kOe magnetic field versus temperature T (MT);

[0034] Figure 4Isothermal magnetization curve (MH) of the magnetization intensity of Cu-Ni-Sn-Mn-B alloy after annealing at 300K as a function of external magnetic field;

[0035] Figure 5 Cu under scanning probe microscopy 61.9 Ni 15 Sn 8 Mn 15 B 0.1 and Cu 56.9 Ni 15 Sn 8 Mn 20 B 0.1 The magnetic domain structure of the alloy photographed after the first annealing at room temperature without an external magnetic field;

[0036] Figure 6 The resistance variation with temperature (RT) curve of Cu-Ni-Sn-Mn-B alloy after the first annealing without external magnetic field;

[0037] Figure 7 The microhardness changes of Cu-Ni-Sn-Mn-B alloy before and after the first annealing;

[0038] Figure 8 Cu 66.9 Ni 15 Sn 8 Mn 10 B 0.1 The real and imaginary parts of the AC magnetic susceptibility of the alloy after the first annealing;

[0039] Fig. 9 Cu 61.9 Ni 15 Sn 8 Mn 15 B 0.1 AC magnetic susceptibility phase of the alloy after the first annealing;

[0040] Fig.10 Cu 61.9 Ni 15 Sn 8 Mn 15 B 0.1 High temperature thermomagnetic curves of the alloy after plastic deformation. DETAILED DESCRIPTION

[0041] This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0042] Note: The Chinese meanings of the English letters in this manual are as follows:

[0043] Oe is the magnetic field intensity, in oersted;

[0044] M is the magnetization intensity, in emu / g;

[0045] K is the thermodynamic temperature, in calvins;

[0046] k is the English abbreviation for "thousand";

[0047] MT is the magneto-thermal curve;

[0048] MH is the isothermal magnetization curve;

[0049] FC is cooling under magnetic field, i.e. Field Cooling;

[0050] FH stands for heating under magnetic field, i.e. FieldHeating.

[0051] The present invention is described in detail below with reference to the embodiments.

[0052] A Cu-Ni-Sn-Mn-B magnetic copper alloy, wherein the chemical molecular formula of the Cu-Ni-Sn-Mn-B magnetic copper alloy is: Cu y Ni 15 Sn 8 Mn x B 0.1 , where x and y are mass percentages, wherein 0≤x≤22wt%, 56.9wt%≤y≤76.9wt%, and x+y+15wt%+8wt%+0.1wt%=100wt%.

[0053] The electronic configuration of Mn is 1s 2 2s 2 2p 6 3s 2 3p 6 3d 5 , manganese atoms have five unpaired electrons and are transition metal elements. There are five electron orbitals in the 3d sublayer, with five electrons arranged in them. These five electrons are arranged in five orbitals respectively, with the same spin. Since each unpaired electron has a spin magnetic moment, manganese has a certain degree of magnetism. The magnetic performance of manganese is related to environmental conditions. When the temperature is lower, the magnetism of manganese is stronger. When it is below room temperature, manganese has ferromagnetism, that is, it can be attracted by a magnet; but when the temperature is higher than room temperature, the magnetism of manganese will gradually weaken until it completely loses its magnetism.

[0054] In this specific embodiment, five alloy compositions and proportions (respectively marked as AE) are designed, as shown in Table 1 below.

[0055] Table 1 Composition and ratio of Cu-Ni-Sn-Mn-B magnetic copper alloy

[0056]

[0057]

[0058] Figure 1 The metallographic micrographs of the above five Cu-Ni-Sn-Mn-B magnetic copper alloys AE under a metallographic microscope are shown. Through metallographic microscope observation, it is found that the alloy has a dendritic structure, and the addition of Mn and B elements reduces the grain size. The finer grain size can improve the mechanical properties of the alloy, such as strength and ductility.

[0059] Figure 2 The X-ray diffraction spectra of the above five Cu-Ni-Sn-Mn-B magnetic copper alloys after annealing are shown. It can be seen from the figure that the main phases of the alloy are α-Cu and Cu 2 NiSn phase.

[0060] A method for preparing a Cu-Ni-Sn-Mn-B magnetic copper alloy comprises the following steps:

[0061] S1. Weigh raw materials according to the composition and atomic percentage of Cu-Ni-Sn-Mn-B magnetic copper alloy, and prepare magnetic copper alloy ingots by vacuum arc melting;

[0062] During the preparation process of Cu-Ni-Sn-Mn-B alloy, the Sn element is prone to grain boundary segregation, which leads to a decrease in performance and brings difficulties to subsequent hot processing, hindering the large-scale application and commercial economic benefits of Cu-Ni-Sn-Mn-B alloy. Compared with the normal melting method, the ingot of vacuum arc melting must be placed in a protective gas (H 2 ) is subjected to a long-term heat preservation treatment (temperature: 820-850°C) and then rapidly cooled (water-cooled) to room temperature. The ingot obtained by vacuum melting has a more uniform distribution of Sn elements, which inhibits the segregation of Sn elements.

[0063] The specific steps include:

[0064] S1-1. Weigh the raw materials of copper, nickel, tin, manganese and boron according to the required proportions. First, prepare a furnace of copper, nickel, tin, manganese and boron in appropriate proportions. Place the weighed raw materials of each element into the crucible in the smelting furnace chamber one by one in the order of melting point from low to high, and ensure that the elements with lower melting points are placed at the bottom of the crucible. Then, by operating the rotating rod, accurately adjust the top position of the tungsten electrode (i.e., the arc-striking electrode) so that the distance between it and the alloy is maintained at about 2 cm. Finally, close the hatch and check whether the hatch is tight, and prepare for the next step;

[0065] S1-2. Start the cooling water circulation system to ensure the cooling effect. Then, use a mechanical pump to evacuate the vacuum chamber until the pressure drops to 10Pa. After completing this step, start to introduce argon gas for gas washing. This process needs to be repeated 3 to 5 times to ensure that the furnace chamber is filled with argon gas, thereby effectively preventing possible oxidation during the smelting process. After the gas washing is completed, use the molecular pump for secondary gas extraction to further increase the vacuum degree in the furnace chamber until the air pressure reaches 5Pa. Through this series of operations, ideal conditions are created for the subsequent smelting process;

[0066] S1-3. Before melting the alloy, it is necessary to perform preliminary melting at a low current state. This is not only convenient for arc initiation, but also can effectively absorb residual gas. Then, the current is gradually increased to melt the raw materials. During the entire melting process, a magnetic stirring bar is required to ensure the uniformity of the sample. After the melting is completed and the sample is cooled, a mechanical shovel is used to turn it over and continue melting. Each sample needs to be melted repeatedly three times to ensure the uniformity of the alloy ingot composition, so as to obtain a high-quality alloy product.

[0067] S2, placing the magnetic copper alloy ingot in a vacuum annealing furnace for the first annealing, the annealing temperature is 800°C, the heat preservation time is 1.5h, and then cooling to room temperature with the furnace;

[0068] Annealing is a metal heat treatment process, which means slowly heating the metal to a certain temperature, keeping it for a sufficient time, and then cooling it at an appropriate speed. The purpose is to reduce hardness, improve machinability; eliminate residual stress, stabilize size, reduce deformation and crack tendency; refine grains, adjust structure, and eliminate structural defects; at the same time, this step can improve the magnetic properties of the alloy;

[0069] In order to eliminate the problems of Sn segregation and excessive dendrite spacing in the cast Cu-Ni-Sn-Mn-B alloy ingot, homogenization annealing is usually used. From the temperature change section of the Cu-Ni-Sn alloy ternary phase diagram, it can be seen that the single-phase temperature range is between 800℃ and 920℃. Since the melting point of tin is only 232℃, the first annealing temperature is reduced and the holding time is reduced to prevent the sample from melting. Then the alloy homogenization temperature is set to 800℃ and the holding time is 1.5h.

[0070] In this specific embodiment, the five alloys were subjected to the first annealing treatment at a temperature of 800°C, and the magneto-thermal curves (MT) of the five alloys before and after annealing were measured using a vibrating sample magnetometer (VSM). The test conditions were: an external magnetic field intensity of 1 kOe and a temperature range of 150-380 K.

[0071] Figure 3The graph shows the change of alloy magnetic properties with temperature. The Curie temperature of the alloy can be estimated using the obtained MT curve. Table 2 shows the Curie temperatures of the five alloys before and after the first annealing. Alloy A does not contain manganese. As expected, the Curie temperature cannot be known from the graph. After annealing, the magnetic properties of the alloy increase and the Curie temperature also increases. The Curie temperature of alloy E is 360K.

[0072] Table 2

[0073]

[0074] The isothermal magnetization curves of the five alloys before and after the first annealing at room temperature (with an applied magnetic field of 5 kOe) were measured by VSM. Figure 4 The magnetization curve of the alloy at room temperature after the first annealing is shown. The residual magnetization, saturation magnetization and coercivity of the alloy can be known from the figure. Table 3 shows the specific data of the residual magnetization, saturation magnetization and coercivity of the alloy. At room temperature, the magnetic properties of the E alloy are 15emu / g, the residual magnetization is less than 1emu / g, and the minimum coercivity is 9Oe.

[0075] Table 3

[0076]

[0077] The resistance of the alloy was tested with VSM to determine how it changes with temperature. The one-word four-wire method was used in the test. The test temperature range was 200K-380K, and the cooling and heating processes were measured simultaneously. Figure 5 The resistance-temperature (RT) curve of the alloy after the first annealing without an external magnetic field is shown.

[0078] Resistivity is an important indicator of the electrical properties of alloys. Table 4 shows the specific data of the resistivity of the alloy before and after the first annealing. The calculation formula for resistivity is: ρ = R × S / L, where ρ represents resistivity, R represents resistance, L represents resistance length, and S represents resistance cross-sectional area. In order to ensure the accuracy of the resistivity test, alloy sheets with consistent length, width, and height were used as much as possible during the test. Table 4 shows the specific data of the resistivity of the alloy before and after annealing. It can be noted that the resistivity of alloy A after annealing is 25% of that of alloy E.

[0079] Table 4

[0080]

[0081] The AC magnetic susceptibility of the annealed alloy was measured by VSM at a test temperature of 50-380K and an AC magnetic field strength of 5Oe. Figure 8 It shows that after the first annealing, Cu 66.9Ni 15 Sn 8 Mn 10 B 0.1 The test results of the real and imaginary parts of the AC magnetic susceptibility of the alloy at different frequencies are given by Figure 8 (a) It can be seen that in the absence of an additional DC magnetic field, at T c In the following temperature range, the value of the real part of the magnetic susceptibility shows a slow downward trend, but the change of the real part of the AC magnetic susceptibility with temperature is independent of frequency, indicating that there is no spin glass component in this system. Figure 8 (b) Cu 62 Ni 15 Sn 8 Mn 15 The test results of the imaginary part of the AC magnetic susceptibility of the alloy at different frequencies. From the figure, it can be seen that the change of the imaginary part of the AC magnetic susceptibility with temperature is closely related to the frequency. As the frequency increases, the value of the imaginary part increases. The higher the frequency, the more obvious the change. The curve of the imaginary part changing with temperature is at T c There is also a peak at , and as the frequency increases, the peak also increases.

[0082] Fig. 9 It shows that after the first annealing, Cu 61.9 Ni 15 Sn 8 Mn 15 B 0.1 The test results of the AC magnetic susceptibility phase of the alloy at different frequencies. The ordinate represents the phase difference between the change of magnetic induction intensity and the change of magnetic field, also known as the loss angle. Fig. 9 It can be seen that in T c Before, the phase did not change, at T c Afterwards, as the frequency increases, the phase increases, and the loss generated increases. The loss mechanism is mainly hysteresis loss, which can be reduced by reducing the coercive force of the material. Therefore, the low coercive force of the Cu-Ni-Sn-Mn-B magnetic copper alloy provided by the present invention can bring changes to the hysteresis loss, reduce the influence of the hysteresis loss, and provide a valuable way for the frequency characteristics of low-frequency motors.

[0083] Fig.10 Cu 61.9 Ni 15 Sn 8 Mn 15 B 0.1 Thermomagnetic curve (MT) of the alloy after plastic deformation. The test conditions are: the external magnetic field intensity is 1kOe, and the test temperature range is 150-750K. Fig.10It can be seen that after 350K, the magnetism of the alloy basically disappears. The cast alloy is plastically deformed. The second annealing temperature of the sample is lower than the original ingot annealing temperature. After the metal material is rolled, its grains will undergo plastic deformation, thereby producing more grain boundaries. At the boundary, the grains will be affected by stress and continue to split, thereby reducing the grain size. Therefore, when the rolling process is improved, the rolling temperature is suitable and the cooling conditions are appropriate, the grain refinement can be effectively promoted by increasing the number of rolling times and reducing the amount of rolling deformation.

[0084] Thirdly, the plastic processing conditions of this type of alloy system and the microstructure evolution data after different deformations are obtained through thermal simulation tests, and the heat treatment process parameters are determined. Then, the magnetic copper alloy ingot after the first annealing is rolled with a total reduction of 20%-25%. After rolling, it is sent to a vacuum annealing furnace for a second annealing. The second annealing temperature is 500°C, the holding time is 1.5h, and then it is cooled to room temperature with the furnace. The magnetic, electrical and mechanical properties of the alloy can be changed through the heat treatment process steps.

[0085] Finally, the magnetic copper alloy ingot after the second annealing is thrown out into a thin strip by a strip-spinning machine, which includes the following steps: placing the Cu-Ni-Sn-Mn-B alloy ingot obtained in the previous step into a quartz tube with a small hole at the bottom, and then placing the quartz tube with the open end facing upward in the furnace chamber of the strip-spinning machine, and extracting the air in the furnace chamber of the strip-spinning machine until the vacuum degree reaches 1.0×10 -3 When the pressure in the furnace chamber of the belt-spinning machine is 0.04-0.05MPa, high-purity argon is introduced into the furnace chamber of the belt-spinning machine; when the pressure in the furnace chamber of the belt-spinning machine is 0.04-0.05MPa, the induction high-frequency heating is started, the current is adjusted, and the power of the induction heating is increased to make the Cu-Ni-Sn-Mn-B alloy ingot in a molten state, and then high-purity argon with a pressure of 3-5Pa is blown into the open end of the quartz tube to spray the molten Cu-Ni-Sn-Mn-B alloy liquid from the small hole onto the high-speed rotating copper wheel (the linear speed is 18m / s), and the Cu-Ni-Sn-Mn-B alloy thin strip sample is thrown out by the copper wheel, and then the magnetic copper alloy thin strip is sent to the vacuum annealing furnace for the third annealing, the third annealing temperature is 500℃, the insulation time is 1.5h, and then it is cooled to room temperature with the furnace to obtain the Cu-Ni-Sn-Mn-B magnetic copper alloy thin strip.

[0086] In summary, the Cu-Ni-Sn-Mn-B magnetic copper alloy prepared by the present invention has good magnetic properties, electrical properties, hardness, etc., and can meet the needs of industrial development at this stage. After experimental verification, the room temperature magnetic properties of the obtained Cu-Ni-Sn-Mn-B alloy are 15emu / g, the Curie temperature is 360K, the Vickers hardness is 245HV, the coercive force is less than 100 Oersteds, the residual magnetization is less than 1emu / g, and the resistivity is 1×10 -7Ω·m, can be widely used in miniature magnetic circuit breakers.

[0087] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A Cu-Ni-Sn-Mn-B magnetic copper alloy, characterized in that: The chemical formula of the Cu-Ni-Sn-Mn-B magnetic copper alloy is: Cu y Ni 15 Sn8Mn x B 0.1 , where x and y are mass percentages, wherein 0≤x≤22wt%, 56.9wt%≤y≤76.9wt%, and x+y+15wt%+8wt%+0.1wt%=100wt%.

2. The Cu-Ni-Sn-Mn-B magnetic copper alloy according to claim 1, characterized in that: The composition and mass percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 3wt%-7wt%, B: 0.1wt%, and the balance is copper.

3. The Cu-Ni-Sn-Mn-B magnetic copper alloy according to claim 1, characterized in that: The composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 8wt%-12wt%, B: 0.1wt%, and the balance is copper.

4. The Cu-Ni-Sn-Mn-B magnetic copper alloy according to claim 1, characterized in that: The composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 13wt%-17wt%, B: 0.1wt%, and the balance is copper.

5. The Cu-Ni-Sn-Mn-B magnetic copper alloy according to claim 1, characterized in that: The composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy are: Ni: 15wt%, Sn: 8wt%, Mn: 18wt%-22wt%, B: 0.1wt%, and the balance is copper.

6. The Cu-Ni-Sn-Mn-B magnetic copper alloy according to claim 1, characterized in that: The room temperature magnetic property of the Cu-Ni-Sn-Mn-B magnetic copper alloy is 15emu / g, the Curie temperature is 360K, the Vickers hardness is 245HV, the minimum coercive force is 9Oe, the residual magnetization is less than 1emu / g, and the resistivity is 1×10 -7 Ω·m.

7. A method for preparing the Cu-Ni-Sn-Mn-B magnetic copper alloy according to any one of claims 1 to 6, characterized in that: The following steps are involved: Firstly, raw materials are weighed according to the composition and atomic percentage of the Cu-Ni-Sn-Mn-B magnetic copper alloy, and a magnetic copper alloy ingot is prepared by vacuum arc melting; Secondly, the magnetic copper alloy ingot is placed in a vacuum annealing furnace for the first annealing at a temperature of 800°C for 1.5 hours, and then cooled to room temperature along with the furnace; Next, the magnetic copper alloy ingot after the first annealing is rolled with a total reduction of 20%-25%, and then sent to a vacuum annealing furnace for a second annealing at a temperature of 500°C for 1.5 hours, and then cooled to room temperature with the furnace; Finally, the magnetic copper alloy ingot after the second annealing is thrown out into a thin strip through a strip throwing machine, and the magnetic copper alloy thin strip is sent to a vacuum annealing furnace for the third annealing. The third annealing temperature is 500°C, the holding time is 1.5h, and then it is cooled to room temperature with the furnace to obtain a Cu-Ni-Sn-Mn-B magnetic copper alloy thin strip.

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