TW201730899A - Method of fabricating iron-based soft magnetic powder - Google Patents

Abstract

A method of fabricating an iron-based soft magnetic powder is described, which comprises the steps of: performing a melting step to cause materials with a predetermining composition ratio to form a melting liquid, wherein a temperature of the melting liquid is ranged from 1519 DEG C to 1588 DEG C; and performing a water spray step, wherein the melting liquid flows from a stream mouth with a bore ranged from 6mm to 8mm, and through a water spray with a water curtain in dual-V shape to cool the melting liquid, so as to fabricate an iron-based soft magnetic powder; wherein the iron-based soft magnetic powder is with an oxygen content between 1820 ppm and 3000 ppm, a permeability between 0 and 125, and a magnetic loss value between 0 and 1000 kw/m3, wherein a weight ratio of the water spray and the melting liquid is between 3.84 and 9.17.

Description

Method for manufacturing iron-based soft magnetic powder

The present invention relates to a method for producing a soft magnetic powder, and more particularly to a method for producing an iron-based soft magnetic powder.

FeSiAl alloy magnetic powder is a kind of soft magnetic metal powder coated with a layer of conductive insulating materials such as water glass, kaolin, phosphate and resin to form so-called soft magnetic composites (SMC). The soft magnetic composite powder can be directly pressed into soft magnetic elements of various shapes by a high-pressure molding machine, and can be directly used after being subjected to appropriate temperature stress elimination annealing, and has three-dimensional uniform magnetic properties. Soft magnetic composite powder can be used as the inductance of passive components, applied to the choke inductor of 3C products, solar and electric vehicles, or common mode filter inductors that filter out electromagnetic interference noise (Common mode choke) ), inductance for power factor correction circuit (PFC). Soft magnetic composite powder can also be developed for anti-lock Braking System (ABS) servo motors, steering wheel hydraulic system motors, pulse transformers for ignition systems, sensors, fuel injection for diesel engines. (Injector) actuators, etc.

The magnetic permeability, magnetic loss, bias-resistant magnetic properties and price of soft magnetic composite materials have their own advantages. Among them, Fe-9.5Si-5.5Al has the advantages of high magnetic permeability, low magnetic loss, low cost and high cost performance. The powder core is widely used in the choke inductor of power supplies.

The preparation method of the iron-iron aluminum alloy magnetic powder includes a casting pulverization method, a gas spray method, and a water spray method. The casting pulverization process includes molten ingots, homogenization annealing and Grinding and grinding, etc., the process length and cost are high, and the powder particles have irregular sharp angles, and the insulating coating effect is poor. The powder produced by the gas jet method is spherical, the apparent density is high, the oxygen content is less than 100ppm, the insulation is coated on the spherical powder, but the density of the pressed magnetic powder core is low, and the porosity is large and reversed. The magnetic field coefficient is high, and the disadvantage of high magnetic permeability is not easily obtained. In order to obtain a high molding density, the powder after the air jet needs to be pulverized to change the spherical shape. Even so, the strength of the pressed magnetic powder core is still poor. The iron strontium aluminum powder prepared by the water spray method has a short process and can be used after the sprayed water is sprayed, and the powder has a long and irregular shape, and the powder preform has high moldability and low forming pressure. The high magnetic core density, magnetic powder core shape retention and strength are superior to those of the spherical powder prepared by the gas spray method, and the composition uniformity is superior to the casting pulverization method, and the powder prepared by the casting pulverization method has the problem of composition segregation. After the iron enamel aluminum powder prepared by the water spray method is coated by insulation, the magnetic permeability and magnetic loss of the prepared soft magnetic composite core are superior to the other two methods. The magnetic loss of the soft magnetic composite core is mainly derived from eddy current loss and magnetic hysteresis loss. The eddy current loss is related to whether the insulation coating of the particles is uniform and whether the insulation resistance is large enough; the uniformity of the insulation coating is related to the particle morphology. The low sharp angle of the particles and the smooth surface help to improve the insulation coating effect. The magnetic hysteresis loss is related to the grain size in the particle. The larger the crystal grain, the smaller the magnetic hysteresis loss. Generally, the larger the powder particle, the larger the inner crystal grain. Regardless of the method used, the particle size of the iron-bismuth aluminum powder is closely related to the magnetic permeability and magnetic loss of the magnetic core. The larger the particle size, the larger the magnetic permeability and magnetic loss.

Generally, the process of spraying water metal powder can be smelted in an induction furnace under the atmosphere or under nitrogen, and the molten alloy molten solution flows vertically into the high-pressure water spray system through the outlet pipe of the liquid separation tank, and the high-temperature molten soup liquid and the high-pressure water beam After the impact is refined into small droplets, it enters the water spray tank for cooling, and after sedimentation and filtration, it is dried at a temperature of 100-120 ° C in a vacuum or in the atmosphere. For iron-based alloys, such as iron-bismuth aluminum alloys, tantalum and aluminum are easily oxidized to form cerium oxide and aluminum oxide during the high-temperature melting process and at the melt outlet nozzle, so when the melt is refined and cooled into powder particles, the powder The inside of the granule contains an oxidizing medium, and the molten iron of the smelting aluminum alloy melts with oxygen decomposed by water vapor, so that alumina is easily formed on the surface of the droplet. The rust of iron in the aforementioned oxide, intercalation and drying processes introduces oxygen into the iron-iron alloy. Among them, the oxide such as When the substance is present in the iron-bismuth aluminum alloy powder, the coercive force (Hc), the magnetic hysteresis loss (Ph) increase, and the magnetic loss increases. In order to reduce the oxygen content of the water spray powder, the improvement equipment is generally used as the starting point, including; (1) the molten soup is not in contact with the atmosphere; (2) the water vapor is prevented from contacting the molten liquid droplets during spraying; or (3) the powder is solidified. After storage in a reducing environment, etc. Alternatively, an element which makes the melt less oxidizable is added to reduce the oxygen content of the water spray metal powder. However, these methods increase manufacturing time and hardware costs.

Therefore, it is necessary to provide a method for manufacturing an iron-based soft magnetic powder to solve the problems of the conventional technology.

The main object of the present invention is to provide a method for producing an iron-based soft magnetic powder, which is subjected to a water spray method under the atmosphere, and controls a parameter in the process to obtain an oxygen content of between 1820 ppm and 3000 ppm and a magnetic permeability of greater than or equal to 125, and an iron-based soft magnetic powder having a magnetic loss value of 0 to 1000 kW/m ³ .

In order to achieve the above object, the present invention provides a method for producing an iron-based soft magnetic powder, comprising the steps of: performing a melting step of smelting a plurality of materials having a predetermined composition ratio to form a molten broth, wherein the molten broth The temperature is between 1519 degrees Celsius and 1588 degrees Celsius; and a water spray step is performed, wherein the molten liquor flows out from a first-class mouth having a diameter of 6 mm to 8 mm, and passes through a water having a double V-shaped water curtain Cooling the molten liquid to obtain an iron-based soft magnetic powder; wherein the iron-based soft magnetic powder has an oxygen content of between 1820 ppm and 3000 ppm, a magnetic permeability of greater than or equal to 125, and a magnetic loss value of 0 to Between 1000kw/m ³ ; wherein the weight ratio of the water mist to the molten liquor is between 3.84 and 9.17.

In an embodiment of the present invention, the water spraying step includes: providing the water mist in a double V-shaped water curtain with a first nozzle group and a second nozzle group, wherein the first nozzle group comprises two opposite nozzles a first water nozzle, and the water mist is ejected from each of the first water nozzles to a first spray distance contacting the molten liquid between 160 mm and 254 mm; and the second nozzle group comprises Two second water nozzles are disposed opposite to each other, and the water mist is ejected from each of the second water nozzles to a second spray distance contacting the molten liquor between 160 mm and 254 mm.

In an embodiment of the present invention, the double V-shaped water curtain is arranged by crossing the first nozzle group and the second nozzle group, and the first water nozzles and the second water nozzles are downwardly arranged. Formed by a tilting spray.

In an embodiment of the invention, the nozzle has a diameter of 6 mm, and the weight ratio of the water mist to the molten liquor is between 5.03 and 9.17 to obtain the oxygen content between 1820 ppm and 2760 ppm. The iron-based soft magnetic powder having a magnetic permeability of between 125 and 130 and a magnetic loss value of between 858 kw/m ³ and 983 kw/m ³ .

In one embodiment of the invention, one of the water mists has a water pressure between 300 and 350 bar.

In an embodiment of the invention, the nozzle has a diameter of 8 mm, the temperature of the molten liquid is between 1521 degrees Celsius and 1547 degrees Celsius, and the weight ratio of the water mist to the molten liquor is Between 3.84 and 4.74, the iron-based soft magnetic powder having the oxygen content between 2350 ppm and 2720 ppm, the magnetic permeability between 134 and 147, and the magnetic loss value between 934 kw/m ³ and 993 kw/m ^{3 is obtained} . body.

In one embodiment of the invention, one of the water mists has a water pressure between 350 and 380 bar.

In an embodiment of the invention, the iron-based soft magnetic powder comprises iron-iron-aluminum soft magnetic powder, iron-iron soft magnetic powder or iron-iron chromium soft magnetic powder.

In an embodiment of the invention, the composition of the iron-based soft magnetic powder comprises: 9.6 wt% to 9.8 wt% of rhodium; 5.3 wt% to 6 wt% of aluminum; and 84.2 wt% to 85.0 wt% of iron.

In one embodiment of the invention, the smelting step is carried out in an atmospheric melting process.

10‧‧‧ method

11‧‧‧Steps

12‧‧‧ steps

21‧‧‧First nozzle group

22‧‧‧second nozzle group

23‧‧‧Water mist

24‧‧‧ molten soup

211‧‧‧First water nozzle

221‧‧‧Second water nozzle

L1‧‧‧first spray distance

L2‧‧‧second spray distance

‧‧‧‧ angle

Fig. 1 is a flow chart showing a method of producing an iron-based soft magnetic powder according to an embodiment of the present invention.

2A is a perspective view showing the first nozzle group and the second nozzle group in the embodiment of the present invention.

2B is a side view of the first nozzle group and the second nozzle group of the embodiment of the present invention schematic diagram.

The above and other objects, features and advantages of the present invention will become more <RTIgt; Furthermore, the directional terms mentioned in the present invention, such as upper, lower, top, bottom, front, rear, left, right, inner, outer, side, surrounding, central, horizontal, horizontal, vertical, longitudinal, axial, Radial, uppermost or lowermost, etc., only refer to the direction of the additional schema. Therefore, the directional terminology used is for the purpose of illustration and understanding of the invention.

Referring to Fig. 1, Fig. 1 is a flow chart showing a method 10 for manufacturing an iron-based soft magnetic powder according to an embodiment of the present invention. The method 10 for manufacturing an iron-based soft magnetic powder according to an embodiment of the present invention mainly comprises the following steps: performing a melting step 11 to melt a plurality of materials having a predetermined composition ratio to form a molten liquid, wherein the temperature of the molten liquid is Between 1519 degrees Celsius and 1588 degrees Celsius; and a water spray step 12, wherein the molten liquor flows from a first-class mouth having a diameter of 6 mm to 8 mm, and is cooled by a water mist in a double V-shaped water curtain. The molten liquid is prepared to obtain an iron-based soft magnetic powder; wherein the iron-based soft magnetic powder has an oxygen content of between 1820 ppm and 3000 ppm, a magnetic permeability of greater than or equal to 125, and a magnetic loss value of from 0 to 1000 kw/ Between m ³ ; wherein the weight ratio of the water mist to the molten liquor is between 3.84 and 9.17.

Referring to FIG. 1 , a method 10 for manufacturing an iron-based soft magnetic powder according to an embodiment of the present invention is first performed by performing a melting step 11 to smelt a plurality of materials having a predetermined composition ratio to form a molten liquid, wherein The temperature of the melt is between 1519 degrees Celsius and 1588 degrees Celsius. In this step, the iron-based soft magnetic powder may comprise iron-iron-aluminum soft magnetic powder, iron-iron soft magnetic powder or iron-iron chromium soft magnetic powder. For example, the composition of the iron-based soft magnetic powder includes: 9.6 wt% to 9.8 wt% of rhodium; 5.3 wt% to 6 wt% of aluminum; 84.2 wt% to 85.0 wt% of iron and unavoidable impurities. In one embodiment, the smelting step is carried out in an atmospheric smelting process, that is, the smelting step is carried out in an atmosphere of an atmosphere other than a specific gas such as nitrogen.

The method 10 for manufacturing an iron-based soft magnetic powder according to an embodiment of the present invention is followed by: performing a water spray step 12, wherein the molten liquid flows out from a first-class nozzle having a diameter of 6 mm to 8 mm, and passes through a double V-shaped water curtain. Cooling the molten liquor to obtain an iron-based soft magnetic powder; wherein the iron-based soft magnetic powder has an oxygen content of between 1820 ppm and 3000 ppm, a magnetic permeability of greater than or equal to 125, and a magnetic loss value Between 0 and 1000 kW/m ³ ; wherein the weight ratio of the water mist to the molten liquor is between 3.84 and 9.17. It should be mentioned that for the weight ratio, the weight of the water mist is calculated based on the water pressure sprayed by the water mist, and the weight of the molten liquid is calculated according to the diameter of the nozzle.

In other words, please refer to Figures 1, 2A and 2B together. Figure 2A is a perspective view of the first nozzle group 21 and the second nozzle group 22 in the embodiment of the present invention. Fig. 2B is a side elevational view showing the first nozzle group 21 and the second nozzle group 22 in the embodiment of the present invention. The water spray step 12 may include: providing the water mist 23 in a double V-shaped water curtain with a first nozzle group 21 and a second nozzle group 22, wherein the first nozzle group 21 includes two first waters disposed opposite to each other. a nozzle 211, and the water mist 23 is ejected from each of the first water nozzles 211 to a first spray distance L1 contacting the molten liquid 24 between 160 mm and 254 mm; and the second nozzle The group 22 includes two second water nozzles 221 disposed opposite to each other, and the water mist is ejected from each of the second water nozzles 221 to a second spray distance L2 contacting the molten liquid 24 at 160 mm to 254. Between millimeters. In a specific embodiment, the double V-shaped water curtain is arranged by crossing the first nozzle group 21 and the second nozzle group 22, and the first water nozzle 211 and the second water nozzles 221 are facing It is formed by performing a tilting spray. In another embodiment, the first spray distance L1 and the second spray distance L2 are adjusted by tilting the first water nozzles 211 and the second water nozzles 221 downward. Taking the inclination angle α of each of the first water nozzles 211 as an example (taking the second water diagram 211 as an example, the first water nozzle 211 positioned on the left side is inclined downward by an angle α, and the first water nozzle 211 positioned on the right side is inclined downward to the left. The angle α), when the inclination angle α of the first water nozzles 211 is 17.5 degrees, the first spray distance L1 is 183 mm; when the inclination angle α of the first water nozzles 211 is 17.5 degrees, the first A spray distance L1 is 254 mm; when the inclination angle α of the first water nozzles 211 is 20 degrees, the first spray distance L1 is 160 mm; and when the first water nozzles 211 When the inclination angle α is 15 degrees, the first spray distance L1 is 212 mm. Similarly, the second water nozzles 221 can also adjust the second spray distance L2 by adjusting the first water nozzles 211. In still another embodiment, the double V-shaped water curtain is a one-sided water curtain.

In one embodiment, the nozzle of the water spray step 12 has a diameter of 6 mm, and the weight ratio of the water mist to the molten liquor is between 5.03 and 9.17 to obtain the oxygen content at 1820 ppm. The iron-based soft magnetic powder is between 2760 ppm, the magnetic permeability is between 125 and 130, and the magnetic loss value is between 858 kw/m ³ and 983 kw/m ³ . In another embodiment, one of the water mists has a water pressure between 300 and 350 bar.

In one embodiment, the nozzle of the water spray step 12 has a diameter of 8 mm, the temperature of the molten solution is between 1521 degrees Celsius and 1547 degrees Celsius, and the water mist and the molten fluid The weight ratio is between 3.84 and 4.74 to produce the oxygen content between 2350 ppm and 2720 ppm, the magnetic permeability is between 134 and 147, and the magnetic loss value is between 934 kw/m ³ and 993 kw/m ³ . Iron-based soft magnetic powder. In another embodiment, one of the water mists has a water pressure between 350 and 380 bar.

In order to prove the method for manufacturing the iron-based soft magnetic powder of the embodiment of the present invention, the water spray method can be used under the atmosphere to obtain an oxygen content between 1820 ppm and 3000 ppm and a magnetic permeability of 125 or more by controlling the parameters in the process. And an iron-based soft magnetic powder having a magnetic loss value of 0 to 1000 kW/m ³ . The following comparative examples and examples are given.

Example 1

First, 9wt% to 10wt% of bismuth raw materials, 5wt% to 6% by weight of aluminum raw materials and the rest of the raw materials of iron are prepared, and the raw materials are smelted in a high-frequency induction furnace with a frequency of 2000 Hz to form a smelting step in an atmosphere to form a Melt solution. The temperature of the molten liquor (hereinafter referred to as the melt temperature; Tm) is subjected to a water spray step at a temperature of 1547 degrees Celsius, wherein the melt liquid is from a nozzle having a nozzle diameter (MOD) of 8 mm (for example, the melt liquid passes through) The nozzle of the alumina tube flows out and is filled with nitrogen gas protection. Thereafter, the mixture was poured into a double V-shaped water curtain to cool the molten liquid by a water mist having a double V-shaped water curtain, thereby producing the iron-based soft magnetic powder of Example 1. The double V-shaped water curtain performs a tilting spray downward through the first nozzle group and the second nozzle group which are arranged in a cross direction, wherein the first spray distance (L1) of the first nozzle group is 183 mm and the second nozzle group is second The spray distance (L2) is 254 mm. Further, the water pressure (P) of the water mist was 350 bar, and the weight ratio (Mw/Mm) of the water mist to the molten liquid was 3.84. The composition of the obtained iron-based soft magnetic powder of Example 1 was: 9.71 wt% of bismuth, 5.8 wt% of aluminum, an oxygen content ([O]) of 2720 ppm, impurities (including manganese, phosphorus, nickel, chromium, copper, Carbon, sulfur, nitrogen, etc.) is about 780 ppm and the remaining component is iron. Thereafter, the iron-based soft magnetic powder of Example 1 was subjected to a screening step to obtain an iron-based soft magnetic powder having a median diameter (D ₅₀ ) of 73.9 μm, coated with water glass insulation, and hard acid ester. Calcium acid is used as a lubricant, and the iron-based soft magnetic powder is pressed at a pressure (X) of 15MT/cm ² to obtain a ring-shaped magnetic powder core which is annealed at 760 degrees Celsius in nitrogen for 30 minutes. The ring-shaped magnetic powder core having a magnetic ratio (μ _e ) of 138 and a magnetic loss P _cv of 979 kW/m ³ was used.

Examples 2 to 9 and Comparative Examples 1 to 8

The manufacturing methods of Examples 2 to 9 and Comparative Examples 1 to 8 were similar to those of Example 1, except that the process parameters and the composition of the obtained iron-based soft magnetic powder, the median diameter, and the obtained ring-shaped magnetic powder core were The characteristics are different, please refer to Tables 1 and 2 below.

Regarding the evaluation method of the characteristics of the toroidal magnetic powder core, the magnetic loss of the toroidal magnetic powder core at a frequency of 100 kHz and a magnetic field of 0.1 Tesla can be measured, for example, by a BH magnetic analyzer (model SY8232) manufactured by IWATSU. The value (P _cv ), and the inductance of the toroidal powder core is measured by an Agilent impedance tester (model LCRZ 42841A/4284A Meter), and calculated by the geometrical path and the magnetic circuit corresponding to the number of coils. Equivalent permeability (μ _e ).

Regarding Comparative Example 1, the weight ratio (Mw/Mm) of the water mist/melting solution was compared. Small (only 2.6), the double V-shaped water curtain, the water vapor pressure is small and can not be liquefied and condensed into water. In addition, the higher the temperature of the molten soup, the water vapor is easily decomposed into oxygen and oxidized with the molten liquid droplets, resulting in an oxygen content of up to 6590 ppm. The oxidation of the particles in the particles, such as alumina, leads to a large magnetic hysteresis loss, and the oxidation is interposed. The object will affect the magnetic domain movement, resulting in a lower magnetic permeability.

Regarding Comparative Example 2, the melt temperature was not as high as 1530 ° C, and Mw / Mm was large (to 5.75), and the water vapor pressure in the square conical water curtain was greatly decomposed into a small amount of oxygen, but the use of the melt caliber Larger, the nozzle diameter MOD is 10 mm, and the large-area melt is pierced by the high-pressure water mist, which increases the number of voids (Voids) of the dissolved soup droplets, thereby increasing the oxidation area and increasing the oxygen content of the powder particles. In addition, the water in the hole has a long residual time, is not easy to dry and is prone to rust. Regarding Comparative Example 3, although the magnetic loss was low, the requirement that the magnetic loss value was less than 1000 kW/m ³ could not be satisfied.

The melt temperature of Comparative Example 4 was higher than that of Comparative Examples 2 and 3, and Mw/Mm was small, but [O] was relatively low, which was 183, 254 mm with the first spray distance L1 and the second spray distance L2, respectively. It is related to 160, 212 mm long of Comparative Examples 2 and 3. In addition, the molten broth first travels in a nitrogen-filled environment, so it takes a long time before contact with the water mist, and the temperature decreases a lot, so the oxidation temperature is low, which also causes [O] to be relatively low. one of the reasons. Furthermore, the first spray distance L1 and the second spray distance L2 are longer, the kinetic energy of the droplet is reduced, and the water pressure is lower, and the impulse of the piercing melt is small, so that less voids are generated, so that [O] is relatively relatively One of the reasons for the low. Regarding Comparative Example 5, although the magnetic loss was low, the requirement that the magnetic loss value was less than 1000 kW/m ³ could not be satisfied.

The nozzle diameter (MOD) used in Comparative Examples 6 to 8 was 8 mm. When the melting temperature Tm is 1543~1578 °C, and the spray water to melt flow ratio Mw/Mm is 3.5~5.08, the oxygen content [O] of the obtained powder is 3630~4210ppm, and [O] is still higher than 3000ppm. The magnetic losses of Comparative Examples 6 and 8 were all higher than 1000 kW/m ³ , and the magnetic loss of Comparative Example 7 was 922 kW/m ³ , although it was less than 1000 kW/m ³ , but the magnetic permeability was only 110. In Comparative Example 7, a large water pressure (450 bar) was used, and the water mist pierced the molten liquid droplets, so that the number of magnetic powder voids increased, resulting in a large internal reverse magnetic field and a low magnetic permeability.

In Examples 1 to 3 and Comparative Examples 6 to 8, a nozzle having a MOD of 8 mm was used, and the obtained powder was obtained at a melt temperature Tm of 1521 to 1547 ° C and a water spray to melt flow ratio Mw/Mm of 3.84 to 4.74. oxygen content [O] is 2350 ~ 2720ppm, magnetic permeability of the magnetic cores 138 to 147, the magnetic loss of 934 ~ 993kW / m ^3, are all smaller than 1000kW / m ^3. In the first and second embodiments, the first first spray distance L1 and the second spray distance L2 are 183 and 254 mm, respectively, so that a shorter spray distance is used with Comparative Example 8, and the Mw/Mm is about 4.74. Examples 1 and 2 gave lower oxygen content.

In Examples 4 to 9, a nozzle having a MOD of 6 mm was used, and the oxygen content [O] of the obtained powder was at a melt temperature Tm of 1519 to 1588 ° C and a spray flow ratio of Mw/Mm of 5.03 to 9.17. 1820~2760ppm, the magnetic permeability of the magnetic powder core is 125~130, the magnetic loss is 858~983kW/m ³ , the magnetic permeability can be greater than or equal to 125, and the magnetic loss is less than or equal to 1000kW/m ³ . Use MOD is 6 mm outflow melt, because the melt outflow rate is slow, Mw/Mm is easy to be greater than or equal to 5. Since the water vapor pressure is large, water vapor is easily liquefied in the double V-shaped water curtain, so oxidation is less. On the other hand, the molten soup has a smaller droplet area facing the water mist, less perforation opportunities, and less oxidation area, so the powder particles have fewer pores, less residual water, and less rust. It is worth mentioning that the melt droplets of Examples 4 to 9 are easily refined, so that the water spray powder is relatively fine.

In summary, the method for manufacturing the iron-based soft magnetic powder according to the embodiment of the present invention can use a water spray method under the atmosphere to obtain an oxygen content between 1820 ppm and 3000 ppm and a magnetic permeability greater than that by controlling the parameters in the process. Is equal to 125, and an iron-based soft magnetic powder having a magnetic loss value of 0 to 1000 kW/m ³ .

The present invention has been disclosed in its preferred embodiments, and is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

10‧‧‧ method

11‧‧‧Steps

12‧‧‧ steps

Claims (10)

A method for producing an iron-based soft magnetic powder, comprising the steps of: performing a melting step of smelting a plurality of materials having a predetermined composition ratio to form a molten liquid, wherein the temperature of the molten liquid is 1519 degrees Celsius to Celsius Between 1588 degrees; and a water spray step, wherein the molten liquid flows out from a first-class mouth having a diameter of 6 mm to 8 mm, and the molten liquid is cooled by a water mist having a double V-shaped water curtain. An iron-based soft magnetic powder; wherein the iron-based soft magnetic powder has an oxygen content of between 1820 ppm and 3000 ppm, a magnetic permeability of greater than or equal to 125, and a magnetic loss value between 0 and 1000 kw/m ³ ; The weight ratio of water mist to the molten liquor is between 3.84 and 9.17. The method for manufacturing an iron-based soft magnetic powder according to the first aspect of the invention, wherein the water spraying step comprises: providing the water mist in a double V-shaped water curtain with a first nozzle group and a second nozzle group, Wherein the first nozzle group includes two first water nozzles disposed opposite to each other, and the water mist is ejected from each of the first water nozzles to a first spray distance contacting the molten liquor at 160 mm to 254 Between millimeters; and the second nozzle group includes two second water nozzles disposed opposite to each other, and the water mist is ejected from each of the second water nozzles to a second spray distance contacting the molten liquor. Between 160 mm and 254 mm. The method for manufacturing an iron-based soft magnetic powder according to the second aspect of the invention, wherein the double V-shaped water curtain is arranged by crossing the first nozzle group and the second nozzle group, and the first water nozzles And the second water nozzles are facing downward Formed by a tilting spray. The method for manufacturing an iron-based soft magnetic powder according to claim 1, wherein the nozzle has a diameter of 6 mm, and a ratio of the water mist to the molten liquid is between 5.03 and 9.17, The iron-based soft magnetic powder having an oxygen content of between 1820 ppm and 2760 ppm, a magnetic permeability of between 125 and 130, and a magnetic loss value of between 858 kw/m ³ and 983 kw/m ³ is obtained. The method for producing an iron-based soft magnetic powder according to the fourth aspect of the invention, wherein the water mist has a water pressure of between 300 and 350 bar. The method for producing an iron-based soft magnetic powder according to claim 1, wherein the nozzle has a diameter of 8 mm, and the temperature of the molten solution is between 1521 ° C and 1547 ° C, and the water The weight ratio of the mist to the molten liquor is between 3.84 and 4.74 to obtain the oxygen content between 2350 ppm and 2720 ppm, the magnetic permeability is between 134 and 147, and the magnetic loss value is 934 kw/m ^{3 .} The iron-based soft magnetic powder to 993 kW/m ³ . The method for producing an iron-based soft magnetic powder according to claim 6, wherein the water mist has a water pressure of between 350 and 380 bar. The method for producing an iron-based soft magnetic powder according to the first aspect of the invention, wherein the iron-based soft magnetic powder comprises iron-iron-aluminum soft magnetic powder, iron-iron soft magnetic powder or iron-iron chromium soft magnetic powder. The method for producing an iron-based soft magnetic powder according to claim 1, wherein the composition of the iron-based soft magnetic powder comprises: 9.6 wt% to 9.8 wt% of niobium; and 5.3 wt% to 6 wt% of aluminum; 84.2 wt% to 85.0 wt% iron. The method for producing an iron-based soft magnetic powder according to claim 1, wherein the melting step is carried out by an atmospheric melting method.