KR102069720B1 - Magnetic alloy for a magnetic ink character recognition ink, alloy powder comprising the same and manufacturing method thereof - Google Patents

Abstract

The present invention relates to magnetic alloy powder for an MICR ink, which can improve reliability and stability of the MICR ink because magnetic properties are superior compared to iron oxide and alloy powder conventionally used. Moreover, at the same time, the magnetic alloy powder for the MICR ink contains magnetic alloy which can provide an economic effect since a raw material of alloy powder is relatively inexpensive. The magnetic alloy powder for the MICR has magnetic properties including: equal to or more than 120 emu/g of saturation magnetization (Ms); equal to or more than 25 emu/g of residual magnetization (Mr); and 300 to 500 Oe of coercive force (Hc).

Description

MAGNETIC ALLOY FOR A MAGNETIC INK CHARACTER RECOGNITION INK, ALLOY POWDER COMPRISING THE SAME AND MANUFACTURING METHOD THEREOF}

The present invention relates to a magnetic alloy for magnetic ink character recognition (MICR) ink, an alloy powder comprising the same, and a manufacturing method of the alloy powder. More specifically, the present invention proposes and applies a magnetic material for a conventional MICR ink. Magnetic powders such as iron oxides (Fe ₃ O ₄ , CoOFe ₂ O ₃ , BaOFe ₂ O _3, etc.) and alloys (CoPt, FePt, FeCo, MnAl, MnBi, Alnico, FeCrCo, Cunife, etc.) The present invention relates to an alloy for MICR ink, an alloy powder comprising the same, and a method of manufacturing the alloy powder, which can reduce the excellent magnetic properties and the cost.

In general, MICR ink magnetic powder material developed for the purpose of preventing and forgery of various banknotes, checks, gift certificates, stamps, etc. is not only magnetic but also stable in various physical / chemical / temporal environmental changes. It is essential.

Magnetic powder used in such a MICR ink is not only a core material of a secure recording medium constituting information encrypted with various characters or shapes, but also a reading device used for accurately detecting or confirming recorded information. It is also important for the accuracy and reliability of reading devices.

Representative materials of the magnetic powder for the conventional MICR ink are ferrite (Fe ₃ O ₄ , CoOFe ₂ O ₃ , BaOFe ₂ O _3, etc.) and alloy (CoPt, FePt, FeCo, MnAl, MnBi, Alnico, FeCrCo, Cunife, etc.) ) Has been developed. In particular, the magnetic properties (saturation magnetization, residual magnetization, coercive force) of the magnetic powder is somewhat different depending on the chemical composition, particle size, shape and manufacturing method of the magnetic powder. Although the saturation magnetization is an intrinsic property of the raw material of the magnetic powder, the residual magnetization and the coercive force, in particular, differ greatly in the microstructure, particle size, shape, etc. of the magnetic powder and depend on the manufacturing process and heat treatment of the powder.

Residual magnetization and coercive force of magnetic powder for MICR ink are properties that maintain accurate information of printed characters or shapes, or play an important role in a readable signal of a reading device.

On the other hand, the residual magnetization (Mr) is important for the particle size and particle size of the magnetic powder because the nozzle size of the ink jet printer is about 40 ~ 50㎛ when printing MICR characters, in particular the particle size is required to be at least 20㎛, As for average particle size (D50), about 10 micrometers is preferable.

Moreover, in general, the residual magnetization (Mr) of the magnetic powder not only decreases as the particle size decreases, but also increases, which is advantageous because it affects the mixing ratio of the magnetic powder and the organic binder, in particular for preparing the MICR ink.

For example, according to Breton et al. (US Pat. No. 8,236,192 B2), among the magnetic properties of magnetic powder for MICR ink, saturation magnetization is not limited but residual magnetization is minimal. It should be more than 20 emu / g, and coercivity of 300 Oe or more suggests that the performance and reliability of the detection signal by the reading device can be improved.

Meanwhile, the magnetic powder for MICR ink used in the proposed technology of Sano et al. (US Pat. No. 6,764,797 B2) is a magnetite (Fe ₃ O ₄ ) powder, which is granular (granular, particle size of 0.2 ~ 0.3㎛, aspect ratio 2.0 or more). Saturation magnetization (Ms) is in the range of 70 ~ 95 emu / g, residual magnetization (Mr) is small in the range of 5 ~ 15 emu / g, but in the case of acicular (particle size of about 0.6㎛, aspect ratio 2.0 or more) The saturation magnetization (Ms) is relatively large, ranging from 70 to 95 emu / g, and the residual magnetization (Mr) from 25 to 40 emu / g.

On the other hand, among the techniques proposed by Gabriel et al. (US Pat. No. 8,801,954 B2), the raw material of magnetic powder is made of Fe, Mn, Co, Ni, FePt, CoPt, MnAl and MnBi alloy 3 to 300nm size nanoparticles Saturation magnetization (Ms) is limited to 20 ~ 150 emu / g range, residual magnetization (Mr) 20 ~ 100 emu / g range and coercive force is limited to 200 ~ 50,000 Oe range to suggest magnetic properties.

In Korean Unexamined Patent Publication No. 10-2017-0078009, Republic of Korea Patent No. 10-1718505, Republic of Korea Patent No. 10-1912100, etc., Alnico, FeCrCo, Cunife alloy powder, especially Alnico-based alloys as raw materials of magnetic powder Was prepared using a water atomization process with a particle size of D50 = 12 μm or less. The saturation magnetization (Ms) was 129.0 emu / g, the residual magnetization (Mr) was 25.8 emu / g, and the coercivity was 392 Oe. Along with the characteristics, the chemical composition of magnetic alloy, powder production method and heat treatment conditions are suggested.

As described above, magnetic powder is a core material of MICR ink raw materials, and in particular, powder materials having better magnetic properties are required to improve reliability and security of applied products, but in addition to these magnetic properties, In addition to stable corrosion resistance, it is important to develop technologies for manufacturing magnetic powder, heat treatment and cost reduction technology.

United States Patent US 8,801,954 B2 (Registration date: Aug. 12, 2014) United States Patent US 8,236,192 B2 (Registration Date: 2012.08.07) United States Patent US 6,764,797 B2 (Registration date: July 20, 2004) Korean Unexamined Patent Publication No. 10-2017-0078009 (published: 2017.07.07) Korea Patent Registration No. 10-1718505 (Registration Date: 2017.03.15) Korea Patent Registration No. 10-1912100 (Registration Date: 2018.10.22)

The technical problem to be solved by the present invention is a new magnetic alloy for MICR ink, alloy powder comprising the same, as well as the magnetic properties suitable for the reliability and stability improvement requirements of MICR ink, as well as the ease and economics of manufacturing magnetic alloy powder and It is to provide a manufacturing method.

In the following description of the present invention, if it is determined that detailed descriptions of related known functions or configurations may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Embodiments according to the concepts of the present invention may be variously modified and have various forms, and specific embodiments will be illustrated in the drawings and described in detail in the present specification or application. However, this is not intended to limit the embodiments in accordance with the concept of the present invention to a particular disclosed form, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. As used herein, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof that is described, and that one or more other features or numbers are present. It should be understood that it does not exclude in advance the possibility of the presence or addition of steps, actions, components, parts or combinations thereof.

As described above, the present invention is iron oxide-based (Fe ₃ O ₄ , CoOFe ₂ O ₃ , BaOFe ₂ O _3, etc.) and alloys (CoPt, FePt, FeCo, MnAl, etc.), which are conventionally used as magnetic powders, which are core materials of MICR ink. , MnBi, Alnico, FeCrCo, Cunife, etc.) to solve the problem of the reliability and stability of the MICR ink with low magnetic properties, and to provide a new alloy powder material with optimized performance as a magnetic powder material for MICR ink.

Conventional Republic of Korea Patent Publication No. 10-2017-0078009, Republic of Korea Patent No. 10-1718505, Republic of Korea Patent No. 10-1912100, etc., Alnico, FeCrCo, Cunife alloy powder, especially Alnico type as the raw material of the magnetic powder From the powder prepared by using water atomization process with particle size D50 = 12μm or less, the saturation magnetization (Ms) is 129.0 emu / g, the residual magnetization (Mr) is 25.8 emu / g and the coercivity is 392 Oe The chemical composition of the magnetic alloy, the powder production method and the heat treatment conditions, and the like are disclosed. However, the magnetic properties of the Alnico-based magnetic powder proposed in the above-mentioned prior patent document are suitable for saturation magnetization (Ms) and coercive force (Hc) as the magnetic powder material for MICR ink, but the residual magnetization (Mr) is not only relatively low, in particular, Co element of alloy composition is 15 ~ 27% by weight, and the price of alloy powder is very expensive.

Therefore, the present invention has more excellent residual magnetization (Mr) and coercive force (Hc), and because the Co element of the alloy composition is used in the range of 4 to 14% by weight, the cost of the alloy powder can be drastically reduced. An object of the present invention is to provide an alloy and an alloy powder comprising the same.

In order to achieve the above technical problem, the present invention is 4.0 to 14.0% by weight of Co; 21.0 to 32.0 weight percent Ni and 0.05 to 15 weight percent X, provided that X is selected from the group consisting of Cu, Al, Ti, Si, Mn, Cr, W, Mo, B, C and rare earth elements (RE) It is proposed a Fe-Co-Ni-X-based alloy for MICR ink, including; one or two or more elements), the balance consisting of Fe and unavoidable impurities.

Here, the Fe-Co-Ni-X-based alloy according to the present invention, the content of X added as an alloying element represents the total content of the two or more alloying elements when X is two or more alloying elements.

On the other hand, the rare earth element (RE), as well as each of the 17 kinds of known rare earth elements, as well as mischmetal (mischmetal).

Generally, iron (Fe) is the most representative element among ferromagnetic materilas, and is a very important element for the magnetic properties of the magnetic powder for MICR ink of the present invention, and the saturation magnetization (Ms) and residual magnetization (Mr) of alloy powder. Not only is it an essential element to improve the cost, but it is advantageous to reduce the cost of the magnetic alloy raw materials because it is relatively cheaper than other elements, but the problem that the coercive force (Oe) decreases with the increase of the corrosion resistance of the magnetic alloy powder when an excessive amount is added have.

Cobalt (Co) is a ferromagnetic material together with the above-mentioned main component Fe, so that the saturation magnetization of the alloy powder decreases in proportion to the amount of addition, but is particularly effective for increasing residual magnetization and coercive force, but it is flexible in terms of price but is 10 times more expensive than Fe. Therefore, in order to reduce the cost of the magnetic alloy powder raw material, it is preferable to add the additive to the minimum.

Nickel (Ni), like Fe and Co, is also one of the representative ferromagnetic materials and is an important element for magnetic properties, and contributes to the increase of saturation magnetization and residual magnetization together with Fe and Co, but is generally hard magnetic. It is important to properly control the amount of addition because it is more effective in reducing coercive force by adding to soft magnet materials than hard magnet materials.

Aluminum (Al) is an element of paramagnetic materials and can reduce the saturation magnetization of alloy powders, but it is a solid solution of Fe in Al-Fe and Si-Al soft magnetic alloy materials that have been developed for a long time. Alternatively, Fe ₃ Al intermetallic compound (DO ₃ type regular lattice phase) is produced, and the magnetostrictive constant (λs) is greatly reduced with the decrease of the crystal anisotropy constant (K ₁ ), which is very effective for improving the soft magnetic properties.

Copper (Cu) is an element of diamagnetic materials, and like Al, it is possible to greatly reduce saturation magnetization. However, copper (Cu) usually contributes to the control of the microstructure of light hard and soft magnetic materials. effective.

Titanium (Ti) and vanadium (V), like Al, are elements of paramagnetic materials, and can usually reduce the saturation magnetization of alloy powders, but, like Cu, contributes greatly to the microstructure control of magnetic alloys. Effective for improvement

Manganese (Mn) and chromium (Cr) are anti-ferromagnetic materilas elements.The reason for adding them to a practical magnetic alloy is to contribute to the improvement of the magnetic properties or the microstructure of the compound produced by solid solution of other elements in the alloy. The magnetic properties are improved, but when added excessively, the residual magnetization and coercive force are lowered, so it is preferable to use the addition amount at 1% by weight or less.

Tungsten (W), molybdenum (Mo), niobium (Nb), and zirconium (Zr) are all paramagnetic materials, and generally can reduce saturation magnetization in magnetic alloys containing mainly Fe, but in particular the microstructure control of magnetic alloys Since it is very effective for, the magnetization is limited because the residual magnetization can be improved by improving the coercive force and improving the coercive force.

Carbon (C) is a non-magnetic nonmetallic element, and when the excess amount is usually added to the magnetic alloy, the saturation magnetization and coercivity can be greatly reduced, so the amount of carbon is limited to the range of 0.02 to 0.25 wt%, but the residual magnetization and coercivity are controlled. In order to be an effective element.

In addition, the present invention is a Fe-Ni-Co-X-based magnetic alloy of iron-based (Fe-based) two-phase separation type (or precipitation type) based on the powder form, the saturation magnetization (Ms) is 120 emu / g or more In this paper, a residual magnetization (Mr) of 25 emu / g or more and a coercive force (Hc) of 300-500 Oe have proposed a Fe-Ni-Co-X-based magnetic alloy for MICR ink.

The Fe-Ni-Co-X-based magnetic alloy according to the present invention is generally applied as a core material of MICR ink in a powder state through a powdering process, and thus the Fe-Ni-Co-X-based composition of the present invention The process for manufacturing is not particularly limited, but may be prepared by gas spraying or gas & water spraying to produce spherical alloy powders, but in order to produce fine powder of 20 μm or less, high pressure water (200bar It is preferable to prepare by the spraying method, and the magnetic alloy powder prepared in the form of powder is necessarily formed by heat treatment for several hours at a temperature in the range of 200 to 800 ° C.

In addition, the Fe-Ni-Co-X alloy powder for MICR ink according to the present invention obtained through the powdering and heat treatment process as described above has a particle diameter of 3 to 20㎛, aspect ratio of 1 to 3. , The average oxygen concentration is 3000 ppm or less, and the specific surface area is preferably 0.3 mm 2 / g or more.

Fe-Ni-Co-X-based alloy powder for MICR ink according to the present invention is conventionally used iron oxide-based (Fe ₃ O ₄ , CoOFe ₂ O ₃ , BaOFe ₂ O _3, etc.) and alloys (CoPt, FePt, FeCo , MnAl, MnBi, Alnico, FeCrCo, Cunife, etc.), the magnetic properties are superior to improve the reliability and stability of the MICR ink, and at the same time can provide an economical effect because the raw material of the alloy powder is relatively inexpensive. .

In addition, since the Fe-Ni-Co-X-based magnetic alloy according to the present invention has excellent magnetic properties, the Fe-Ni-Co-X-based magnetic alloy is made of a bonded magnet or a sintered magnet using an epoxy binder, and thus, various electric and It can be used as a material for electronic parts and biosensors.

Figure 1 is a SEM observation of the alloy powder sample of Example 35 of the present application.
2 is a result of XRD analysis of the alloy powder sample of Example 35 of the present application.
3 is a result of measuring the magnetic properties of the sample according to the change in the addition amount of cobalt (Co) of the alloy powder in the present invention by VSM.
4 is a result of measuring the magnetic properties of the sample according to the change in the amount of addition of nickel (Ni) of the alloy powder in VSM.
5 is a result of measuring the magnetic properties of the sample according to the change in the addition amount of aluminum (Al) of the alloy powder in the present invention by VSM.
6 is a result of measuring the magnetic properties of the sample according to the change in the addition amount of copper (Cu) of the alloy powder in VSM.
7 is a result of measuring the magnetic properties of the sample according to the change in the addition amount of titanium (Ti) of the alloy powder in VSM.
8 is a result of measuring the magnetic properties of the sample according to the change in the high-pressure water injection pressure in the production of the alloy powder in the present invention by VSM.
9 is a result of analyzing the oxygen (O ₂ ) content of the same alloy powder shown in FIG. 8 in the present invention.
FIG. 10 shows the powders classified into four types (-325 to + 400mesh, -400 to + 500mesh, -500 to + 635mesh, and -635mesh) of the alloy powder of Example 5 shown in Table 1 in the present invention under the same heating conditions. Heat treatment (700 ℃ x 30min → furnace cooling) to measure the magnetic properties.
FIG. 11 is a result of measuring magnetic properties of a sample obtained by quenching the alloy powder of Example 35 shown in Table 1 by changing the heat treatment time to 670˜695 ° C. for 40 minutes.

The present invention may be modified in various ways and may have various embodiments. Specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to the specific embodiments, it should be understood that it includes all changes, equivalents, and substitutes included in the spirit and scope of the present invention, and may be modified in various other forms. The scope of the present invention is not limited to the examples.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying tables and drawings in order to enable those skilled in the art to easily carry out the present invention.

<Example> Preparation of Fe-based magnetic alloy powder for MICR ink and evaluation of physical properties

Fe-Co-Ni-X-based magnetic alloy powder having the composition shown in Tables 1 and 2 below was filled with an alumina (or magnesia) crucible with a total amount of commercially available reagent grade raw metal 300 g as an electronic balance, and then subjected to a high frequency induction heating method. It was dissolved (1600 ℃ or more) and prepared in powder form by a high pressure water spray method (annular nozzle 7 mm, 110 ~ 180 bar range). The prepared alloy powder was dried and classified into 400mesh (less than 37㎛), and heat-treated by heating in the range of 200 ~ 850 ° C. in an Ar atmosphere using a tube electric furnace.

Magnetic properties of the magnetic alloy powder prepared as described above were measured by a vibration sample magnetic measuring device (VSM, TAMAKWA-TM-WLF10515R-156), some alloy samples were analyzed by SEM / XRD to observe the microstructure.

TABLE 1

TABLE 2

1 and 2 are the results observed and analyzed by SEM and XRD of the alloy powder sample of Example 35. Particle size and shape of the alloy powder may vary depending on the manufacturing method and grinding conditions, and in particular, the particle size is important to classify to 20㎛ or less considering the nozzle size of the MICR ink jet printer, the shape is spherical (Or sub-spherical), flax ratios of 1 to 3 are suitable. In addition, the XRD analysis results shown in FIG. 2 show that the phase change before and after the heat treatment of the alloy powder is closely related to the enhancement of residual magnetization and coercive force among the magnetic properties of the alloy powder. Particularly, a fine new peak was observed around 2θ = 30. Other major peaks did not change much but were slightly broadened.

(1) Magnetic Properties of Alloy Powders with Cobalt (Co) and Nickel (Ni) Additions

3 and 4 are the results of measuring the alloy powder samples heat-treated equally under the composition and heat treatment conditions of the alloy shown in Table 1 and Table 2 by VSM.

Cobalt (Co) is a ferromagnetic material together with the above-mentioned main component Fe, so that the saturation magnetization of the alloy powder is slightly reduced in proportion to the amount of addition, but is particularly effective in increasing the residual magnetization and coercive force, and is particularly flexible in terms of price, but is 10 times higher than Fe. In order to reduce the cost of the magnetic alloy powder raw material, it is preferable to limit the addition to the minimum.

Example 36, Example 33, Example 32 and Example 30 shown in Figure 3 of the present invention is an alloy powder prepared by changing the amount of Co added in the weight ratio of 6 to 12%, Ms as the amount of Co added increases Decreases, but it can be seen that Mr and Hc increase linearly. In particular, the addition of Co is very effective for the increase of Mr, and the magnetic properties are greatly changed in conjunction with the addition amount of Ni and Al. In addition, since Hc is limited to 500 Oe or less and at the same time, the addition amount is suitably in the range of 5 to 14% by weight, and more preferably in the range of 8 to 12%.

Nickel (Ni), like Fe and Co, is one of the representative ferromagnetic materials and contributes to the increase of saturation magnetization and residual magnetization with Fe and Co, but it is important to properly control the amount of addition because it affects the coercive force. Do.

Example 2, Example 9, Example 3 and Example 4 shown in Figure 4 of the present invention was prepared by varying the amount of Ni added in the range of 21 to 22.5% by weight, Ms and Mr decreases as the amount added increases However, it can be seen that Hc increases significantly. This magnetic property is important to control the appropriate amount because the difference is large depending on the amount of Co and the amount of Al described later, in particular, in order to obtain a reduction of Mr and Hc within 500 Oe to be limited to 21 to 32% by weight It is preferable.

(2) Magnetic Properties of Alloy Powders According to Aluminum (Al), Copper (Cu) and Titanium (Ti) Additions

5, 6 and 7 are the results of measuring the alloy powder samples heat-treated in the same manner in the composition and aging treatment conditions of the alloy shown in Table 1 and Table 2 by VSM.

Aluminum (Al) is an element of paramagnetic materials and can reduce the saturation magnetization of alloy powders, but it is a solid solution of Fe in Al-Fe and Si-Al soft magnetic alloy materials that have been developed for a long time. Alternatively, Fe ₃ Al intermetallic compounds (DO ₃ type regular lattice phases) are formed, and the magnetic anisotropy constant (K1) is reduced and the magnetostrictive constant (λs) is greatly reduced, which is very effective for improving soft magnetic properties.

Example 17, Example 15, Example 13, and Example 14 shown in FIG. 5 of the present invention change the amount of Al added in the range of 6 to 8% by weight, and as described above, Ms increases as the amount added increases. Significantly decreases but Hc also increases greatly with Mr. In particular, the magnetic properties are greatly changed in conjunction with the addition amount of Co and Ni, and it is preferable to limit the addition amount to 6-9% by weight in order to obtain an Hc value within the range of 500 Oe with an increase in the Mr value.

Copper (Cu) is an element of diamagnetic materials, and like Al, it is possible to greatly reduce the saturation magnetization, and is effective in improving the coercive force because it is involved in the microstructure control by heat treatment of the alloy powder.

Example 21, Example 20, Example 17, and Example 19 shown in FIG. 6 of this invention are a case where the addition amount of Cu is changed to 1.9 to 2.8% of range by weight ratio. In particular, Ms decreases with increasing amount of Cu, while Mr increases up to 2.2%, but more than 2.5% decreases significantly. It can also be seen that the Hc increases to 2.5% but decreases slightly above it. This magnetic property change is linked to the amount of Ti to be described later, it is preferable to limit the addition amount to 1.5 to 3% by weight for the appropriate Mr and Hc.

Titanium (Ti) and vanadium (V), like Al, are elements of a paramagnetic material and can usually lower the saturation magnetization of alloy powders. However, like Cu mentioned above, it is effective for improving the coercive force as an element which greatly contributes to the microstructure by heat treatment of the magnetic alloy.

Example 24, Example 21, Comparative Example 50 and Example 23 shown in Figure 7 of the present invention is a case in which the addition amount of Ti in the range of 4.8 to 5.4% by weight ratio, Ms is as described above with increasing Al and Similar to Cu, it is slightly decreased, but it can be seen that Mr and Hc are greatly increased. This change in magnetic properties is linked to the amount of Cu described above, and since Hc increases and Mr also increases greatly, it is preferable to limit the amount of Hc to 4 to 6.5% by weight in order to obtain 500 Oe or less.

(3) Magnetic properties of alloy powders depending on the amount of carbon (C) and other elements (Mn, Cr, W, Mo, B, Nd)

Carbon (C) is a nonmetallic element that can generally lower the magnetic properties of magnetic alloys. In the present invention, as a result of changing the weight ratio of alloy powder to 0.02 to 0.3%, all of Ms, Mr, and Hc are increased as the amount of addition increases. Somewhat reduced. However, in the Fe-Co-Ni-X-based alloy composition of the present invention, in particular, in order to obtain appropriate Mr and Hc (500 Oe or less) of the alloy powder, it is preferable to limit it to 0.02 to 0.25% by weight.

On the other hand, the alloy samples of Comparative Example 15, Comparative Example 16, Comparative Example 21, Comparative Example 22, Comparative Example 17, and Comparative Example 23 shown in Table 1 of the present invention, Mn, Cr, W, Mo, B, Nd elements by weight ratio The magnetic properties of the alloy powders prepared by 1.0% substitution were measured by VSM. Particularly, when Mn, Cr, and Nd elements were added, relatively high values of Mr and Hc were obtained. On the other hand, a lower value of Hc was obtained in the sample to which B was added. As described above, Mn and Cr are antiferromagnetic materials, and in the Al-Co-Ni-X-based alloy of the present invention, when a small amount of 0.05 to 2% is added in a weight ratio, it is dissolved in Fe of the alloy, or Mn Compounds such as -Al-based or Fe-Cr-Co-based may be formed, which may be advantageous to magnetism. However, when 2% or more is added in the weight ratio of the alloy powder, Ms may be lowered. It is preferable. In addition, W and Mo are both paramagnetic materials, and generally can reduce Ms of the magnetic alloy mainly composed of Fe, but in particular, the addition amount is 3.0% by weight in order to improve Mr and Hc by homogenizing alloy powder and controlling microstructure. It is preferable to subtract within.

Nd is a representative antiferromagnetic metal element of rare-earth elements 4f transition metals (Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, etc.). Solid solution in Fe, Co, Ni element of magnetic alloy powder or intermetallic compound (RCo ₅ , RCo ₁₇ , Nd ₂ Fe ₁₄ B) is formed to increase the crystal anisotropy constant (K ₁ ) of alloy powder and Hc Since it can be improved, it is preferable to limit the addition amount to 1.0% by weight or less in order to actually increase the appropriate magnetic properties (Hc = 500 Oe or less), improve oxidation resistance, and reduce cost.

(4) Magnetic properties of alloy powders according to powder production, milling time and heat treatment conditions

8 and 9 are Examples 22, 28 and 24 shown in Table 2 are prepared by changing the discharge port injection pressure (bar) of the high pressure water injection nozzle to 110 ~ 180 bar when manufacturing the magnetic alloy powder will be. As shown in FIG. 8, Ms and Hc decreased slightly with increasing injection pressure, but Mr increased. Also, as shown in FIG. 9, the amount of oxygen decreased as the injection pressure increased. . These results are related to homogenization and miniaturization of alloy powders by cooling rate, and it is difficult to determine characteristics and phenomena with current data alone, and detailed experiments and considerations are required in the future.

10 is a total amount of 100g of the alloy powder of Example 5 shown in Table 1 in a stainless steel ball mill container, after milling, the alloy powder using a sieve -325 ~ + 400mesh, -400 ~ + 500mesh, -500 Magnetic properties were measured by aging treatment (700 ℃ x30min → furnace cooling) under the same heat treatment conditions. Ms is not significantly different according to the ball milling time, but it can be seen that Mr and Hc are greatly reduced.

11 is the same as the alloy powder of Example 35 shown in Table 2 to 670 ℃, 675 ℃, 680 ℃, 685 ℃, 690 ℃ and 695 ℃ to hold for 40 minutes to measure the magnetic properties of the sample obtained by cold cooling It is. In particular, Ms does not change much, but it can be seen that Mr and Hc changes significantly.

Although the present invention has been described based on preferred embodiments and comparative examples, the technical idea of the present invention is not limited thereto, and modifications or changes can be made within the scope of the claims. It will be apparent to those having the right to make such modifications and variations belong to the appended claims.

Claims (12)

5.0 to 14.0 wt.% Co;
21.0 to 32.0 weight percent Ni;
6.0-9.0 wt% aluminum (Al);
1.5 to 3.0 weight percent copper (Cu);
4.0 to 6.5 weight percent titanium (Ti); And
0.02 to 0.25 weight percent carbon (C),
The balance consists of Fe and inevitable impurities,
Fe-Co-Ni-X alloy for MICR ink. The method of claim 1,
Fe-Co-Ni-X-based alloy for MICR ink, characterized in that it further comprises 0.16 to 0.48% by weight of silicon (Si). delete delete delete Fe-Co-Ni-X type alloy powder for MICR ink containing the alloy of Claim 1. The method of claim 6,
Saturation magnetization (Ms) is 120 emu / g or more, residual magnetization (Mr) is 25 emu / g or more and the coercive force (Hc) is characterized in that the magnetic properties of Fe-Co- for MICR ink Ni-X alloy powder. The method of claim 6,
Fe-Co-Ni-X-based alloy powder for MICR ink, characterized in that the particle size is 3 to 20 ㎛. The method of claim 6,
Fe-Co-Ni-X-based alloy powder for MICR ink, characterized in that the aspect ratio is 1 to 5. The method of claim 6,
Fe-Co-Ni-X alloy powder for MICR ink, characterized in that the average oxygen concentration is 3000 ppm or less. The method of claim 6,
Fe-Co-Ni-X-based alloy powder for MICR ink, characterized by a specific surface area of 0.3 mm 2 / g or more. (a) 5.0 to 14.0 weight percent Co; 21.0 to 32.0 weight percent Ni; 6.0-9.0 wt% aluminum (Al); 1.5 to 3.0 weight percent copper (Cu); 4.0 to 6.5 weight percent titanium (Ti); And preparing an alloy molten metal including 0.02 to 0.25% by weight of carbon (C), the balance consisting of Fe and inevitable impurities; And
(b) preparing the alloy molten metal in the form of a powder by gas spraying or water spraying;
The manufacturing method of the Fe-Co-Ni-X type alloy powder for MICR inks of Claim 6.

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