A low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy and preparation method thereof

Abstract

The present invention discloses a low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy and a preparation method thereof. The amorphous alloy is expressed as: Fe a Co b M c B d , where 60at%≤a≤92at%, 0at%<b≤24at%, 5at%≤c≤15at%, 2at%≤d≤8at%; M is one or more of Hf, Nb, and Zr; and the soft magnetic corrosion-resistant iron-based amorphous alloy is in the form of a strip. The linear expansion coefficient of the amorphous alloy in the temperature range of ‑60℃~100℃ is 2*10 ‑6 The amorphous alloy of the present invention has low thermal expansion coefficient, high corrosion resistance and excellent magnetic properties, and can be used as electromagnetic device materials in the case of large thermal fluctuations, seawater corrosion and the like.

Description

Technical Field

[0001] The invention belongs to the field of low expansion soft magnetic materials and relates to a low thermal expansion soft magnetic corrosion-resistant iron-based amorphous alloy and a preparation method thereof. Background Art

[0002] Electromagnetic devices used in mechanical and electronic equipment will be affected by deformation caused by thermal expansion in areas with large temperature differences or in special thermal response projects, which may affect the normal use of the devices. For example, the temperature of transformer core materials is relatively low (~-20℃) in the cold northern winter, but the temperature may reach ~90℃ during operation. The thermal deformation causes the air gap loss to increase, exceeding the user's original design data. Moreover, in some corrosive environments, traditional core materials are prone to corrosion, resulting in reduced shielding effect and a sharp drop in soft magnetic properties.

[0003] The thermal expansion coefficient of the soft magnetic materials currently used in China is 6.46*10 -6 , Silicon steel thermal expansion coefficient ~12.54*10 -6 With the large-scale application of soft magnetic materials, for some harsh working environments (large temperature difference, hot and humid salt spray, seawater, etc.), more and more situations require multifunctional soft magnetic materials with a wider range of adaptability.

[0004] For multifunctional soft magnetic materials, amorphous ribbons have become a very reliable candidate. Compared with crystalline materials, amorphous materials have long-range disorder in structure, do not have common crystal structure defects, show a lower thermal expansion coefficient, and have excellent soft magnetic properties (low coercivity, low loss, etc.). Nowadays, amorphous soft magnetic materials have become very critical basic materials in the fields of electronic information and electricity. Considering that the current soft magnetic materials (such as 1k101, 1k107) will have a significant decrease in saturation magnetic induction intensity after being corroded, and are prone to deformation in environments with large temperature differences, affecting performance. Therefore, it is necessary to develop new types of materials with low thermal expansion (that is, a thermal expansion coefficient less than 2*10 -6 )Corrosion-resistant soft magnetic materials have important application prospects and scientific value. Summary of the invention

[0005] The invention discloses a low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy and a preparation method thereof, so as to solve any of the above and other potential problems of the prior art.

[0006] To achieve the above object, the technical solution of the present invention is: a low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy, the expression of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy is: Fe a Co b M c Bd , wherein 60at%≤a≤92at%, 0at%<b≤24at%, 5at%≤c≤15at%, 2at%≤d≤8at%, a+b+c+d=100%; M is one or more of Hf, Nb, and Zr; and the soft magnetic corrosion-resistant iron-based amorphous alloy is in the form of strips.

[0007] Further, the expression of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy is: Fe a Co b M c B d , wherein 65at%≤a≤85at%, 5at%<b≤23at%, 6at%≤c≤12at%, 3at%≤d≤7at%, a+b+c+d=100%; and M is one or more of Hf, Nb, and Zr.

[0008] Further, 9≤b≤22, 5.5≤c≤11.5, 3≤d≤6.5.

[0009] Furthermore, the linear expansion coefficient of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy in the temperature range of -60°C to 100°C is 2*10 -6 Below; saturation magnetic induction intensity Bs is 1.3T-1.8T; coercive force Hc is below 25A / m, and annual corrosion rate is below 0.00001mm / year.

[0010] Further, when a=75at%, b15at%, c10at%, d=5at%, the expression of the soft magnetic corrosion-resistant iron-based amorphous alloy is: Fe 70 Co 15 M 10 B5, the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy has a linear expansion coefficient of 0.05 to 0.50*10 in the temperature range of -60℃ to 100℃. -6 ; In the temperature range of -60~300℃ of Curie point, the thermal expansion coefficient is kept stable at -2.81*10 -6 .

[0011] Another object of the present invention is to provide a method for preparing the above-mentioned low thermal expansion soft magnetic corrosion-resistant iron-based amorphous alloy, characterized in that the method specifically comprises the following steps:

[0012] S1) According to the expression of amorphous alloy Fe a Co b M c B d , weigh each raw material separately and set aside;

[0013] S2) placing the raw materials weighed in S1) into an arc melting furnace, first evacuating the furnace, then filling it with protective gas, and after the raw materials are completely melted, further melting for a certain period of time to obtain an alloy ingot with uniform composition;

[0014] S3) The alloy ingot obtained in S2) is prepared by a single-roll melt rapid quenching method to obtain a strip of a soft magnetic and corrosion-resistant iron-based amorphous alloy with low thermal expansion.

[0015] Furthermore, the method further comprises a testing step:

[0016] The strip obtained in S3) is placed in a neutral NaCl solution with a mass concentration of 3.5wt.%, and is subjected to 100°C and 200°C, respectively, for 24 hours; and after 100 cycles of thermal shock tests, the thermal expansion coefficient remains stable (-196°C to 100°C).

[0017] Further, the vacuum degree in S2) is less than 2×10 -3 Pa; the protective atmosphere is nitrogen or argon, and the remelting time is 5 to 30 minutes.

[0018] Further, the specific steps of S3) are:

[0019] S3.1) breaking the alloy ingot obtained in S2) into small pieces of alloy, loading them into a quartz glass tube with an opening at the lower end after cleaning, and then placing them in the induction coil of the belt-spinning device;

[0020] S3.2) Vacuum to 2×10 -3 After Pa, high-purity argon is filled as a protective gas. After the current is adjusted to heat to a certain temperature to completely melt the alloy, the molten alloy liquid is sprayed onto the surface of the copper roller rotating at a certain linear speed using the gas pressure difference to produce a continuous, low thermal expansion, soft magnetic, and corrosion-resistant iron-based amorphous alloy strip.

[0021] Furthermore, the temperature is controlled at 1200-1400° C., the surface linear speed of the copper roller is 30-55 m / s, the thickness of the strip is 10-30 μm, and the width of the strip is 1-3 mm.

[0022] A strip of a soft magnetic and corrosion-resistant iron-based amorphous alloy with low thermal expansion is prepared by the above method.

[0023] In summary, the beneficial technical effect of the present invention is that it can simultaneously obtain low thermal expansion, high corrosion resistance and excellent soft magnetic properties, and can be used as electromagnetic device materials in harsh environments, such as large temperature changes, seawater corrosion, etc. Compared with the existing iron-based soft magnetic amorphous alloys, when the Fe element content is appropriately reduced (less than 85%), the formability, forming ability and thermal stability of the prepared amorphous soft magnetic alloy are improved; the Co element can regulate the amorphous forming ability, coercive force and corrosion resistance of the material, and more importantly, it can affect the Curie temperature and thermal expansion properties of the material. When its content is lower than 7%, the Curie temperature, amorphous forming ability and corrosion resistance will decrease significantly. When its content is higher than 25%, the thermal expansion coefficient will increase significantly; through the addition of transition elements, the corrosion resistance of the material is greatly improved; the B element as a small semi-precipitate, the Co element can effectively improve the corrosion resistance of the material. Non-metallic elements can improve the amorphous forming ability and stability. When the content is lower than 3%, the thermal stability of the amorphous soft magnetic material deteriorates and the formability decreases, making it difficult to meet the operating temperature of the transformer core. However, when the B content is higher than 12 atomic %, further increase in its content basically has no significant contribution to the amorphization of the alloy, but will reduce the magnetic saturation strength of the alloy. At the same time, Fe and Co elements jointly affect the thermal expansion coefficient and thermal expansion temperature zone. When the Fe content is lower than 60%, the thermal expansion coefficient increases significantly, showing a conventional positive expansion material. When the Fe content is higher than 85%, the low thermal expansion temperature zone will be significantly shortened to less than 200°C. The above four elements jointly affect the amorphous forming ability and thermal stability. The specific beneficial effects are as follows:

[0024] 1) It has a low thermal expansion coefficient. The linear expansion coefficient of the low thermal expansion amorphous alloy is 0.05 to 0.5*10 in the temperature range of -60℃ to 100℃. -6 , below the Curie point (300°C), the thermal expansion coefficient remains stable (-2.81*10 -6 , -60~300℃), the thermal expansion coefficient remains stable (-196℃ to 100℃) after being kept at 100℃ and 200℃, and after 100 cycles of thermal shock tests;

[0025] 2) It has a high saturation magnetic induction intensity, Bs is above 1.3T and below 1.8T; the coercive force Hc is below 20A / m;

[0026] 3) It has high corrosion resistance. After being immersed in a neutral NaCl solution with a mass concentration of 3.5wt.% for 120 days, most areas of the amorphous alloy surface still show metallic luster, and the annual corrosion rate is below 0.00001mm / year, which is significantly lower than that of 1J36 corrosion-resistant soft magnetic alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The Fe prepared in Examples 1, 2 and 3 of the present invention70 Co 15 Hf 10 B5 X-ray diffraction pattern of amorphous strip;

[0028] Figure 2 The Fe prepared in Examples 1, 2 and 3 of the present invention 60 Co 15 Hf 10 The thermal expansion curve of B5 amorphous strip is compared with commercial 1k107 and silicon steel;

[0029] Figure 3 The Fe prepared in Example 1 of the present invention 70 Co 15 Hf 10 BH hysteresis loop of B5 amorphous strip. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0031] The present invention discloses a low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy. The expression of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy is: Fe a Co b M c B d , wherein 60at%≤a≤92at%, 0at%<b≤24at%, 5at%≤c≤15at%, 2at%≤d≤8at%, a+b+c+d=100%; M is one or more of Hf, Nb, and Zr; and the soft magnetic corrosion-resistant iron-based amorphous alloy is in the form of strips.

[0032] The expression of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy is: Fe a Co b M c B d , wherein 65at%≤a≤85at%, 5at%<b≤23at%, 6at%≤c≤12at%, 3at%≤d≤7at%, a+b+c+d=100%; and M is one or more of Hf, Nb, and Zr.

[0033] Among them, 9≤b≤22, 5.5≤c≤11.5, 3≤d≤6.5.

[0034] The linear expansion coefficient of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy in the temperature range of -60°C to 100°C is 2*10 -6Below; saturation magnetic induction intensity Bs is 1.3T-1.8T; coercive force Hc is below 25A / m, and annual corrosion rate is below 0.00001mm / year.

[0035] When a=75at%, b15at%, c10at%, d=5at%, the expression of the soft magnetic corrosion-resistant iron-based amorphous alloy is: Fe 70 Co 15 M 10 B5, the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy has a linear expansion coefficient of 0.05 to 0.50*10 in the temperature range of -60℃ to 100℃. -6 ; In the temperature range of -60~300℃ of Curie point, the thermal expansion coefficient is kept stable at -2.81*10 -6 .

[0036] A method for preparing the above-mentioned low thermal expansion soft magnetic corrosion-resistant iron-based amorphous alloy, the method specifically comprising the following steps:

[0037] S1) According to the expression of amorphous alloy Fe a Co b M c B d , weigh each raw material separately and set aside;

[0038] S2) placing the raw materials weighed in S1) into an arc melting furnace, first evacuating the furnace, then filling it with protective gas, and after the raw materials are completely melted, further melting for a certain period of time to obtain an alloy ingot with uniform composition;

[0039] S3) The alloy ingot obtained in S2) is prepared by a single-roll melt rapid quenching method to obtain a strip of a soft magnetic and corrosion-resistant iron-based amorphous alloy with low thermal expansion.

[0040] The method further comprises the step of testing:

[0041] The strip obtained in S3) is placed in a neutral NaCl solution with a mass concentration of 3.5wt.%, and is subjected to 100°C and 200°C, respectively, for 24 hours; and after 100 cycles of thermal shock tests, the thermal expansion coefficient remains stable (-196°C to 100°C).

[0042] The vacuum degree in S2) is less than 2×10 -3 Pa; the protective atmosphere is nitrogen or argon, and the remelting time is 5 to 30 minutes.

[0043] The specific steps of S3) are:

[0044] S3.1) breaking the alloy ingot obtained in S2) into small pieces of alloy, loading them into a quartz glass tube with an opening at the lower end after cleaning, and then placing them in the induction coil of the belt-spinning device;

[0045] S3.2) Vacuum to 2×10 -3 After Pa, high-purity argon is filled as a protective gas. After the current is adjusted to heat to a certain temperature to completely melt the alloy, the molten alloy liquid is sprayed onto the surface of the copper roller rotating at a certain linear speed using the gas pressure difference to produce a continuous, low thermal expansion, soft magnetic, and corrosion-resistant iron-based amorphous alloy strip.

[0046] The temperature is controlled at 1200-1400° C., the surface linear speed of the copper roller is 30-55 m / s, the thickness of the strip is 10-30 μm, and the width of the strip is 1-3 mm.

[0047] A strip of a soft magnetic and corrosion-resistant iron-based amorphous alloy with low thermal expansion is prepared by the above method.

[0048] Embodiment 1:

[0049] Iron-based soft magnetic amorphous alloy is an amorphous alloy strip with the molecular formula Fe 70 Co 15 Hf 10 B5.

[0050] The specific preparation method of the above-mentioned iron-based soft magnetic amorphous alloy is as follows:

[0051] S1) According to the molecular formula Fe 70 Co 15 Hf 10 B5 prepares raw materials, and prepares raw materials Fe, Co, Hf, and B, specifically: converts the atomic percentage of the alloy into mass percentage, and weighs them respectively according to the proportion, and the purity of each raw material is greater than 99.9%;

[0052] S2) Place the prepared raw materials in S1) into a high-frequency induction melting furnace and evacuate to 2×10 -3 Pa, fill in an appropriate amount of argon as a protective gas, adjust the current until the raw materials are completely melted, and then smelt for 15 minutes, wait for the alloy to cool, and obtain an alloy ingot with uniform composition;

[0053] S3) The ingot obtained in S2) is broken into small pieces of alloy, which are then cleaned and placed in a quartz glass tube with an open lower end, and then placed in an induction coil of a belt-spinning device and evacuated to 2×10 -3After 1000 Pa, a proper amount of high-purity argon was filled as a protective gas. After adjusting the current to heat to 1370℃ to completely melt the alloy, the molten alloy liquid was sprayed onto the surface of the copper roller with a rotation speed of 52m / s by using the pressure difference to obtain a continuous strip with a thickness of 20μm and a width of 2mm. The X-ray diffraction pattern of the amorphous strip is as follows: Figure 1 As shown, the diffraction pattern shows that the alloy strips are amorphous structures;

[0054] Fe 70 Co 15 Hf 10 The BH hysteresis loop of the B5 amorphous strip is shown in Figure 3 shown.

[0055] Fe 70 Co 15 Hf 10 BH hysteresis loop of amorphous strip B5 X-ray diffraction pattern of amorphous strip, such as Figure 1 As shown, the diffraction pattern shows that the alloy strips have an amorphous structure.

[0056] Embodiment 2:

[0057] Iron-based soft magnetic amorphous alloy is an amorphous alloy strip with the molecular formula Fe 66 Co 19 Hf 10 B5.

[0058] The specific preparation method of the above-mentioned iron-based soft magnetic amorphous alloy is as follows:

[0059] S1) According to the molecular formula Fe 66 Co 19 Hf 10 B5 prepares raw materials, and prepares raw materials Fe, Co, Hf, and B, specifically: converts the atomic percentage of the alloy into mass percentage, and weighs them respectively according to the proportion, and the purity of each raw material is greater than 99.9%;

[0060] S2) Place the prepared raw materials in S1) into a high-frequency induction melting furnace and evacuate to 2×10 -3 Pa, fill in an appropriate amount of argon as a protective gas, adjust the current until the raw materials are completely melted, and then smelt for 20 minutes, wait for the alloy to cool, and obtain an alloy ingot with uniform composition;

[0061] S3) The ingot obtained in S2) is broken into small pieces of alloy, which are then cleaned and placed in a quartz glass tube with an open lower end, and then placed in an induction coil of a belt-spinning device and evacuated to 2×10 -3After the molten alloy is completely melted, the molten alloy liquid is sprayed onto the surface of the copper roller with a rotation speed of 52m / s using the pressure difference to obtain a continuous strip with a thickness of about 20μm and a width of about 2mm. The X-ray diffraction pattern of the amorphous strip is as follows: Figure 1 As shown, the diffraction pattern shows that the alloy strips have an amorphous structure.

[0062] Embodiment 3:

[0063] Iron-based soft magnetic amorphous alloy is an amorphous alloy strip with the molecular formula Fe 63 Co 22 Hf 10 B5.

[0064] The specific preparation method of the above-mentioned iron-based soft magnetic amorphous alloy is as follows:

[0065] S1) According to the molecular formula Fe 63 Co 22 Hf 10 B5 prepares raw materials, and prepares raw materials Fe, Co, Hf, and B, specifically: converts the atomic percentage of the alloy into mass percentage, and weighs them respectively according to the proportion, and the purity of each raw material is greater than 99.9%;

[0066] S2) Place the prepared raw materials in S1) into a high-frequency induction melting furnace and evacuate to 2×10 -3 Pa, fill in an appropriate amount of argon as a protective gas, adjust the current until the raw materials are completely melted, and then smelt for 20 minutes, wait for the alloy to cool, and obtain an alloy ingot with uniform composition;

[0067] S3) The ingot obtained in S2) is broken into small pieces of alloy, which are then cleaned and placed in a quartz glass tube with an open lower end, and then placed in an induction coil of a belt-spinning device and evacuated to 2×10 -3 After the molten alloy is completely melted, the molten alloy liquid is sprayed onto the surface of the copper roller with a rotation speed of 52m / s using the pressure difference to obtain a continuous strip with a thickness of about 20μm and a width of about 2mm. The X-ray diffraction pattern of the amorphous strip is as follows: Figure 1 As shown, the diffraction pattern shows that the alloy strips have an amorphous structure.

[0068] The thermal expansion coefficients of the strip samples in Examples 1, 2, and 3 are compared with those of commercial 1k107, silicon steel, and iron. Figure 2 As shown, the thermal expansion coefficient of Example 2 is: 1.06*10 -6 (-60~330℃), the thermal expansion coefficient of Example 3 is: 2.18*10 -6(-60~400℃) is a low thermal expansion sample.

[0069] Embodiment 4:

[0070] Iron-based soft magnetic amorphous alloy is an amorphous alloy strip with the molecular formula Fe 70 Co 15 Nb 10 B5.

[0071] The specific preparation method of the above-mentioned iron-based soft magnetic amorphous alloy is as follows:

[0072] S1) According to the molecular formula Fe 70 Co 15 Nb 10 B5 prepares raw materials, and prepares raw materials Fe, Co, Nb, and B, specifically: converts the alloy atomic percentage into mass percentage, and weighs them respectively according to the proportion, and the purity of each raw material is greater than 99.9%;

[0073] S2) Place the prepared raw materials in S1) into a high-frequency induction melting furnace and evacuate to 2×10 -3 Pa, fill in an appropriate amount of argon as a protective gas, adjust the current until the raw materials are completely melted, and then smelt for 15 minutes, wait for the alloy to cool, and obtain an alloy ingot with uniform composition;

[0074] S3) The ingot obtained in S2) is broken into small pieces of alloy, which are then cleaned and placed in a quartz glass tube with an open lower end, and then placed in an induction coil of a belt-spinning device and evacuated to 2×10 -3 After Pa, an appropriate amount of high-purity argon is filled in as a protective gas, and the current is adjusted to heat to 1370°C to completely melt the alloy. The molten alloy liquid is then sprayed onto the surface of the copper roller with a rotation speed of 52m / s using the gas pressure difference to produce a continuous strip with a thickness of 12μm and a width of 1.7mm.

[0075] Embodiment 5:

[0076] Iron-based soft magnetic amorphous alloy is an amorphous alloy strip with the molecular formula Fe 70 Co 15 Zr 12 B3.

[0077] The specific preparation method of the above-mentioned iron-based soft magnetic amorphous alloy is as follows:

[0078] S1) According to the molecular formula Fe 70 Co 15 Zr 12 B3 preparing raw materials, mixing raw materials Fe, Co, Zr and B, specifically: converting the alloy atomic percentage into mass percentage, weighing them respectively according to the proportion, and the purity of each raw material is greater than 99.9%;

[0079] The raw materials were placed in a high-frequency induction melting furnace and vacuumed to 2×10 -3 Pa, fill in an appropriate amount of argon as a protective gas, adjust the current until the raw materials are completely melted, and then smelt for 15 minutes, wait for the alloy to cool, and obtain an alloy ingot with uniform composition;

[0080] S3) The ingot obtained in S2) is broken into small pieces of alloy, which are then cleaned and placed in a quartz glass tube with an open lower end, and then placed in an induction coil of a belt-spinning device and evacuated to 2×10 -3 After Pa, an appropriate amount of high-purity argon is filled in as a protective gas. After the current is adjusted to heat to 1370°C to completely melt the alloy, the molten alloy liquid is sprayed onto the surface of the copper roller with a rotation speed of 38m / s using the gas pressure difference to produce a continuous strip with a thickness of 25μm and a width of 1.2mm.

[0081] The above is a detailed introduction to a low thermal expansion, soft magnetic, corrosion-resistant iron-based amorphous alloy and a preparation method thereof provided in the embodiments of the present application. The above embodiments are only used to help understand the method and its core idea of ​​the present application; at the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

[0082] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different nouns to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. As mentioned throughout the specification and claims, "including" and "comprising" are open-ended terms, so they should be interpreted as "including / including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect. The subsequent description of the specification is a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application, and is not used to limit the scope of the present application. The scope of protection of the present application shall be subject to that defined in the attached claims.

[0083] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0084] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0085] The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present application, and should be within the scope of protection of the claims attached to the present application.

Claims

1. A low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy, characterized in that: The expression of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy is: Fe a Co b M c B d , wherein 60at%≤a≤92at%, 0at%<b≤24at%, 5at%≤c≤15at%, 2at%≤d≤8at%, a+b+c+d=100%; the M is one or more of Hf, Nb, and Zr; and the soft magnetic corrosion-resistant iron-based amorphous alloy is in the shape of a strip; the linear expansion coefficient of the low thermal expansion soft magnetic corrosion-resistant iron-based amorphous alloy in the temperature range of -60℃~100℃ is 2*10 -6 Below; saturation magnetic induction intensity Bs is 1.3T-1.8T; coercive force Hc is below 25A / m, and annual corrosion rate is below 0.00001mm / year.

2. The low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy according to claim 1, characterized in that: The expression of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy is: Fe a Co b M c B d , wherein 65at%≤a≤85at%, 5at%<b≤23at%, 6at%≤c≤12at%, 3at%≤d≤7at%, a+b+c+d=100%; the M is one or more of Hf, Nb, and Zr; the linear expansion coefficient of the low thermal expansion soft magnetic corrosion-resistant iron-based amorphous alloy in the temperature range of -60℃~100℃ is 2*10 -6 Below; saturation magnetic induction intensity Bs is 1.3T-1.8T; coercive force Hc is below 25A / m, and annual corrosion rate is below 0.00001mm / year.

3. The low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy according to claim 1 or 2, characterized in that: When a=70at%, b=15at%, c=10at%, d=5at%, the expression of the soft magnetic corrosion-resistant iron-based amorphous alloy is: Fe 70 Co 15 M 10 B5, the linear expansion coefficient of the low thermal expansion soft magnetic corrosion resistant iron-based amorphous alloy is 0.05~0.50*10 in the temperature range of -60℃~100℃ -6 ; In the temperature range of -60~300℃ of Curie point, the thermal expansion coefficient is kept stable at -2.81*10 -6 .

4. A method for preparing a low thermal expansion, soft magnetic, corrosion-resistant iron-based amorphous alloy as claimed in any one of claims 1 to 3, characterized in that: The method specifically comprises the following steps: S1) According to the expression of amorphous alloy Fe a Co b M c B d , weigh each raw material separately and set aside; S2) placing the raw materials weighed in S1) into an arc melting furnace, first evacuating the furnace, then filling it with protective gas, and after the raw materials are completely melted, further melting for a certain period of time to obtain an alloy ingot with uniform composition; S3) The alloy ingot obtained in S2) is prepared by a single-roll melt rapid quenching method to obtain a strip of a low thermal expansion, soft magnetic, and corrosion-resistant iron-based amorphous alloy.

5. The method according to claim 4, characterized in that The method further comprises a testing step: placing the strip obtained in S3) in a NaCl solution, subjecting the strip to 100°C and 200°C, respectively, keeping the temperature for 24 hours or subjecting the strip to 100 cycles of thermal shock testing, and the thermal expansion coefficient remains stable.

6. The method according to claim 4, characterized in that The vacuum degree in S2) is less than 2×10 -3 Pa; the protective atmosphere is nitrogen or argon, and the remelting time is 5 to 30 minutes.

7. The method according to claim 4, characterized in that The specific steps of S3) are: S3.1) breaking the alloy ingot obtained in S2) into small pieces of alloy, loading them into a quartz glass tube with an opening at the lower end after cleaning, and then placing them in the induction coil of the belt-spinning device; S3.2) Vacuum to 2×10 -3 After Pa, high-purity argon is filled as a protective gas. After the current is adjusted to heat to a certain temperature to completely melt the alloy, the molten alloy liquid is sprayed onto the surface of the copper roller rotating at a certain linear speed using the gas pressure difference to produce a continuous, low thermal expansion, soft magnetic, and corrosion-resistant iron-based amorphous alloy strip.

8. The method according to claim 7, characterized in that The temperature is controlled at 1200-1400° C., the surface linear speed of the copper roller is 30-55 m / s, the thickness of the strip is 10-30 μm, and the width of the strip is 1-3 mm.

9. A strip of a soft magnetic and corrosion-resistant iron-based amorphous alloy with low thermal expansion, characterized in that: The strip of the low thermal expansion, soft magnetic, corrosion-resistant iron-based amorphous alloy is produced by the method according to any one of claims 5 to 8.

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