阅读说明：本技术 宽温高磁导率软磁铁氧体材料及其元件制备方法 (Wide-temperature high-permeability soft magnetic ferrite material and preparation method of element thereof ) 是由 杨仕机 王宏 窦海之 于 2021-07-23 设计创作，主要内容包括：本发明公开了宽温高磁导率软磁铁氧体材料及其元件制备方法,所述宽温高磁导率软磁铁氧体材料包括主料和辅料,按照质量百分比计：主料占比≥99.50％；辅料占比≤0.5％；所述主料包括：三氧化二铁、氧化锰、氧化锌,其中,按质量百分比计：三氧化二铁50.5％-52.5％；氧化锰24.5％-26.5％；氧化锌22％-24％；所述辅料包括：碳酸钙、氧化铜、三氧化二铋、二氧化硅、氧化锡、五氧化二铌、二氧化钛、三氧化二钴、三氧化钼和二氧化钨。本发明通过添加辅料,并控制辅料总量在0.5％以下,通过辅料配合加强铁氧体材料的磁通密度,以提高环境适应性,降低在恶劣环境中使用损耗过大的问题,从而提高宽温高磁导率软磁铁氧体材料的综合性能。(The invention discloses a wide-temperature high-permeability soft magnetic ferrite material and a preparation method of elements thereof, wherein the wide-temperature high-permeability soft magnetic ferrite material comprises main materials and auxiliary materials, and the main materials and the auxiliary materials are calculated according to the mass percentage: the proportion of the main material is more than or equal to 99.50 percent; the proportion of the auxiliary materials is less than or equal to 0.5 percent; the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 50.5 to 52.5 percent of ferric oxide; 24.5 to 26.5 percent of manganese oxide; 22% -24% of zinc oxide; the auxiliary materials comprise: calcium carbonate, copper oxide, bismuth trioxide, silicon dioxide, tin oxide, niobium pentoxide, titanium dioxide, cobaltous trioxide, molybdenum trioxide and tungsten dioxide. According to the invention, the auxiliary materials are added, the total amount of the auxiliary materials is controlled to be below 0.5%, and the magnetic flux density of the ferrite material is enhanced through the matching of the auxiliary materials, so that the environmental adaptability is improved, the problem of overlarge loss in severe environment is reduced, and the comprehensive performance of the wide-temperature high-permeability soft magnetic ferrite material is improved.)

1. The wide-temperature high-permeability soft magnetic ferrite material is characterized in that: the wide-temperature high-permeability soft magnetic ferrite material comprises main materials and auxiliary materials, and comprises the following components in percentage by mass: the proportion of the main material is more than or equal to 99.50 percent; the proportion of the auxiliary materials is less than or equal to 0.5 percent;

the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 50.5 to 52.5 percent of ferric oxide; 24.5 to 26.5 percent of manganese oxide; 22% -24% of zinc oxide;

the auxiliary materials comprise: calcium carbonate, copper oxide, bismuth trioxide, silicon dioxide, tin oxide, niobium pentoxide, titanium dioxide, cobaltous trioxide, molybdenum trioxide and tungsten dioxide;

the auxiliary materials are divided into a first auxiliary material group according to the preparation process of the wide-temperature high-permeability soft magnetic ferrite material: prepared by mixing calcium carbonate, copper oxide and niobium pentoxide;

a second adjuvant group: is prepared by mixing bismuth trioxide, molybdenum trioxide and silicon dioxide;

a third auxiliary material group: is prepared from cobaltous oxide, titanium dioxide and tungsten dioxide.

2. The wide temperature high permeability soft magnetic ferrite material as claimed in claim 1, wherein: the bismuth trioxide adopts delta-Bi 2O3 and has a cubic fluorite structure, 1/4 oxygen ion positions in crystal lattices are vacant, and the bismuth trioxide has very high oxygen ion conductivity.

3. The wide temperature high permeability soft magnetic ferrite material as claimed in claim 1, wherein: the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 50.5 percent of ferric oxide; 26.5 percent of manganese monoxide; 23 percent of zinc oxide.

4. The wide temperature high permeability soft magnetic ferrite material as claimed in claim 1, wherein: the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 51.5% of ferric oxide; 25.5 percent of manganese oxide; 23 percent of zinc oxide.

5. The wide temperature high permeability soft magnetic ferrite material as claimed in claim 1, wherein: the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 52.5 percent of ferric oxide; 24.5 percent of manganese monoxide; 23 percent of zinc oxide.

6. A method for preparing a wide temperature range high permeability soft magnetic ferrite element as claimed in claim 1, characterized in that: the method comprises the following steps:

s1, preparing materials, namely weighing the materials for later use according to the formula of the wide-temperature high-permeability soft magnetic ferrite material by mass percentage;

s2, adding the three raw material powders of the main material into a stirring tank, mixing and stirring, and adding deionized water and a hydroxymethyl cellulose dispersant during stirring;

s3, putting the uniformly stirred main material into a ball mill for ball milling, and performing spray drying after ball milling for 4-6 hours;

s4, pre-burning the main material, namely ball-milling the first auxiliary material group, melting the ball-milled main material group into liquid at high temperature, adding the dried main material, and pre-burning at 860-960 ℃ for 60-90 minutes to obtain a pre-burned material;

s5, mixing the second auxiliary material group and the third auxiliary material group with the pre-sintering material and carrying out secondary ball milling, and simultaneously carrying out independent ball milling on the first auxiliary material group;

s6, carrying out spray granulation on the pre-sintered material, the second auxiliary material group and the third auxiliary material group subjected to secondary ball milling to obtain granules, and carrying out compression molding to obtain a raw blank;

s7, sintering the green blank at high temperature in an atmosphere with 2-8% of oxygen content;

and S8, cooling the sintered blank to prepare the high-permeability soft magnetic ferrite core.

7. The method for preparing a wide-temperature-range high-permeability soft magnetic ferrite element according to claim 6, wherein the method comprises the following steps: in the spray granulation described in step S6, the pre-fired material, the second auxiliary material group, and the third auxiliary material are mixed with a polyvinyl alcohol binder, a hydroxymethyl cellulose dispersant, and a dimethyl silicone oil defoaming agent to perform granulation.

8. The method for preparing a wide-temperature-range high-permeability soft magnetic ferrite element according to claim 6, wherein the method comprises the following steps: and (4) performing heat preservation sintering at the high temperature in the step S7, wherein the sintering temperature is 1300-1380 ℃.

Technical Field

The invention belongs to the technical field of new materials, and particularly relates to a wide-temperature high-permeability soft magnetic ferrite material; meanwhile, the invention also relates to a preparation method of the wide-temperature high-permeability soft magnetic ferrite element.

Background

When the magnetic conductivity of the material is higher, the required inductance can be obtained by fewer turns of the coil, so that the direct current resistance of the coil and the loss caused by the direct current resistance are effectively reduced; and secondly, the volume of the transformer can be obviously reduced by using the material with high magnetic conductivity, thereby being beneficial to the miniaturization and the light weight of devices and systems. These characteristics are in line with the development trend of electronic products, and the yield of the electronic products accounts for more than 25% of the total yield of all soft magnetic ferrites at present. With the rapid development of electronic information industries such as communication, computer, network, etc., the market demand is growing at a high rate of more than 20% per year;

research in the field of high magnetic permeability has been shifted from the aspect of simply pursuing high magnetic permeability to the aspect of improving comprehensive performance, which is the development trend of current high magnetic permeability ferrites, common soft magnetic ferrite materials generally have other dopants added in the preparation process to ensure the self high magnetic permeability of elements under different environments to ensure the self practicality, but the comprehensive performance is not good enough, and the comprehensive adaptive effects such as high use temperature, environmental loss and the like are difficult to ensure, so that the wide-temperature high magnetic permeability soft magnetic ferrite material and the element preparation method thereof are provided.

Disclosure of Invention

The invention aims to solve the defects in the prior art, and provides a wide-temperature-range high-permeability soft magnetic ferrite material and a preparation method of an element thereof.

In order to achieve the purpose, the invention provides the following technical scheme:

the wide-temperature-range high-permeability soft magnetic ferrite material comprises main materials and auxiliary materials, and comprises the following components in percentage by mass: the proportion of the main material is more than or equal to 99.50 percent; the proportion of the auxiliary materials is less than or equal to 0.5 percent;

the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 50.5 to 52.5 percent of ferric oxide; 24.5 to 26.5 percent of manganese oxide; 22% -24% of zinc oxide;

the auxiliary materials comprise: calcium carbonate, copper oxide, bismuth trioxide, silicon dioxide, tin oxide, niobium pentoxide, titanium dioxide, cobaltous trioxide, molybdenum trioxide and tungsten dioxide;

the auxiliary materials are divided into a first auxiliary material group according to the preparation process of the wide-temperature high-permeability soft magnetic ferrite material: prepared by mixing calcium carbonate, copper oxide and niobium pentoxide;

a second adjuvant group: is prepared by mixing bismuth trioxide, molybdenum trioxide and silicon dioxide;

a third auxiliary material group: is prepared from cobaltous oxide, titanium dioxide and tungsten dioxide.

Preferably, the bismuth trioxide adopts delta-Bi 2O3, has a cubic fluorite structure, is vacant in oxygen ion position 1/4 in crystal lattice, and has very high oxygen ion conductivity.

Preferably, the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 50.5 percent of ferric oxide; 26.5 percent of manganese oxide; 23 percent of zinc oxide.

Preferably, the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 51.5% of ferric oxide; 25.5 percent of manganese oxide; 23 percent of zinc oxide.

Preferably, the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 52.5 percent of ferric oxide; 24.5 percent of manganese oxide; 23 percent of zinc oxide.

A preparation method of a wide-temperature high-permeability soft magnetic ferrite element comprises the following steps:

s1, preparing materials, namely weighing the materials for later use according to the formula of the wide-temperature high-permeability soft magnetic ferrite material by mass percentage;

s2, adding the three raw material powders of the main material into a stirring tank, mixing and stirring, and adding deionized water and a hydroxymethyl cellulose dispersant during stirring;

s3, putting the uniformly stirred main material into a ball mill for ball milling, and performing spray drying after ball milling for 4-6 hours;

s4, pre-burning the main material, namely ball-milling the first auxiliary material group, melting the ball-milled main material group into liquid at high temperature, adding the dried main material, and pre-burning at 860-960 ℃ for 60-90 minutes to obtain a pre-burned material;

s5, mixing the second auxiliary material group and the third auxiliary material group with the pre-sintering material and carrying out secondary ball milling, and simultaneously carrying out independent ball milling on the first auxiliary material group;

s6, carrying out spray granulation on the pre-sintered material, the second auxiliary material group and the third auxiliary material group subjected to secondary ball milling to obtain granules, and carrying out compression molding to obtain a raw blank;

s7, sintering the green blank at high temperature in an atmosphere with 2-8% of oxygen content;

and S8, cooling the sintered blank to prepare the high-permeability soft magnetic ferrite core.

Preferably, in the spray granulation in step S6, the pre-sintered material, the second auxiliary material group, and the third auxiliary material are mixed with a polyvinyl alcohol binder, a hydroxymethyl cellulose dispersant, and a dimethyl silicone oil defoamer to perform granulation.

Preferably, the step S7 is performed by sintering at 1300-1380 ℃ under high temperature.

The invention has the technical effects and advantages that:

1. compared with the traditional soft magnetic ferrite material, the wide-temperature high-permeability soft magnetic ferrite material provided by the invention has the advantages that the auxiliary material is added, the total amount of the auxiliary material is controlled to be below 0.5%, the wide-temperature characteristic of the ferrite material is improved through the matching of the auxiliary material, the high initial permeability is ensured, the use temperature and the environmental adaptability of the magnetic core are improved, and the comprehensive performance of the wide-temperature high-permeability soft magnetic ferrite material is improved.

2. According to the invention, the first auxiliary material group after ball milling is melted into a liquid state at high temperature, and then the raw blank is added into the atmosphere with 2-8% of oxygen content for heat preservation sintering at high temperature, so that the sintering temperature is reduced, the sintering solid phase reaction is greatly accelerated, the magnetic core density is increased, and the initial magnetic conductivity of the material is improved.

Drawings

FIG. 1 is a flow chart of the preparation method of the wide-temperature high-permeability soft magnetic ferrite element of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a wide-temperature high-permeability soft magnetic ferrite material, which comprises main materials and auxiliary materials in percentage by mass: the proportion of the main material is more than or equal to 99.50 percent; the proportion of the auxiliary materials is less than or equal to 0.5 percent.

Example 1

The main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 50.5 percent of ferric oxide; 26.5 percent of manganese oxide; 23% of zinc oxide;

the auxiliary materials comprise: calcium carbonate, copper oxide, bismuth trioxide, silicon dioxide, tin oxide, niobium pentoxide, titanium dioxide, cobaltous trioxide, molybdenum trioxide and tungsten dioxide;

optionally, on the basis of the main materials, the formula of the main materials is different from that of the main materials in that: the main materials comprise: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 51.5% of ferric oxide; 25.5 percent of manganese oxide; 23% of zinc oxide;

optionally, on the basis of the main materials, the formula of the main materials is different from that of the main materials in that: ferric oxide, manganese oxide and zinc oxide, wherein the mass percentages are as follows: 52.5 percent of ferric oxide; 24.5 percent of manganese oxide; 23% of zinc oxide;

in the auxiliary materials, the first auxiliary material group is prepared by mixing calcium carbonate, copper oxide and niobium pentoxide as raw materials, so that the hardness, rigidity and heat resistance (the characteristics of the calcium carbonate) of the wide-temperature high-permeability soft magnetic ferrite material are improved, the copper oxide is used as an electrode active material, the permeability of the wide-temperature high-permeability soft magnetic ferrite material is improved to a certain extent, and the use of the niobium pentoxide improves the weather resistance to a certain extent, so that the wide-temperature high-permeability soft magnetic ferrite material has higher initial permeability at normal temperature and ensures the initial permeability of the material at low temperature or high temperature, thereby achieving the purpose of wide-temperature high permeability;

among the above-mentioned auxiliary materials, the second auxiliary material group: the flame-retardant coating is prepared by mixing bismuth trioxide, molybdenum trioxide and silicon dioxide, wherein the bismuth trioxide is delta-Bi 2O3 and has a cubic fluorite structure, 1/4 oxygen ion positions in crystal lattices are vacant, the flame-retardant coating has very high oxygen ion conductivity, the molybdenum trioxide has certain flame retardance, and the silicon dioxide can be used as a lubricant, is an excellent flow promoter and mainly serves as a lubricant, an anti-adhesion agent and a flow aid;

among the above-mentioned auxiliary materials, the third auxiliary material group: the magnetic ferrite is prepared from cobaltous oxide, titanium dioxide and tungsten dioxide, wherein the cobaltous oxide can generate relatively good magnetic conductivity, so that the magnetic conductivity of the wide-temperature high-magnetic-conductivity soft magnetic ferrite material is improved, the titanium dioxide can adsorb opposite charges in a liquid (especially polar) medium due to the surface charges to form a diffusion double electric layer, the effective diameter of particles is increased, and when the particles approach each other, the particles repel each other due to the like charges, so that the stability of a dispersion system is facilitated;

by adding the auxiliary materials and controlling the total amount of the auxiliary materials to be below 0.5%, the wide-temperature characteristic of the ferrite material is improved through the matching of the auxiliary materials, and high initial permeability is ensured, so that the use temperature and the environmental adaptability of the magnetic core are improved, and the comprehensive performance of the wide-temperature high-permeability soft magnetic ferrite material is improved.

Example 2

On the basis of the material of the embodiment 1, the preparation method of the wide-temperature-range high-permeability soft magnetic ferrite element comprises the following steps:

s1, preparing materials, namely weighing the materials for later use according to the formula of the wide-temperature high-permeability soft magnetic ferrite material by mass percentage;

s2, adding the three raw material powders of the main material into a stirring tank, mixing and stirring, and adding deionized water and a hydroxymethyl cellulose dispersant during stirring;

s3, putting the uniformly stirred main material into a ball mill for ball milling, and performing spray drying after ball milling for 4-6 hours;

s4, pre-burning the main material, namely ball-milling the first auxiliary material group, melting the ball-milled main material group into liquid at high temperature, adding the dried main material, and pre-burning at 860-960 ℃ for 60-90 minutes to obtain a pre-burned material;

s5, mixing the second auxiliary material group and the third auxiliary material group with the pre-sintering material and carrying out secondary ball milling, and simultaneously carrying out independent ball milling on the first auxiliary material group;

s6, carrying out spray granulation on the pre-sintered material, the second auxiliary material group and the third auxiliary material group subjected to secondary ball milling to obtain granules, and carrying out compression molding to obtain a raw blank;

in the spray granulation in the step S6, the pre-fired material, the second auxiliary material group and the third auxiliary material are mixed with a polyvinyl alcohol binder, a hydroxymethyl cellulose dispersant and a dimethyl silicone oil defoamer for granulation;

s7, sintering the green blank at high temperature in an atmosphere with 2-8% of oxygen content;

performing heat preservation sintering at the high temperature in the step S7, wherein the sintering temperature is 1300-1380 ℃;

the sintering process is not only complicated, but also is very variable, and in minutes or even seconds, the sintering material is heated to 1200-1400 ℃ from below 70 ℃ due to strong heat exchange, and meanwhile, the liquid phase is generated from the solid phase and is rapidly cooled and solidified. These physicochemical changes include:

(1) combustion and heat exchange of fuel;

(2) evaporation and condensation of moisture;

(3) decomposition of carbonate, volatilization of volatile components in fuel;

(4) oxidation, reduction and decomposition of iron minerals;

(5) oxidation and removal of sulfides;

(6) solid phase reaction and liquid phase generation;

(7) cooling and condensing of the liquid phase, reoxidation of the sintered ore, and the like.

And S8, cooling the sintered green material to prepare the high-permeability soft magnetic ferrite element.

The first auxiliary material group after ball milling is melted into liquid at high temperature, and then the raw blank is added into the atmosphere with 2-8% of oxygen content for heat preservation and sintering at high temperature, so that the sintering temperature is reduced, the sintering solid phase reaction is greatly accelerated, the magnetic core density is increased, and the initial magnetic conductivity of the material is improved;

optionally, the pre-sintering and sintering in step S4 and step S7 are all performed by using a mesh-belt sintering furnace, the mesh-belt sintering furnace is composed of a driving device, a burning-out region, a sintering region, a cooling region (water jacket cooling type), a feeding device, a discharging device, a heating device, various pipes, and electrical and testing devices,

pre-burning area

In order to ensure that the evaporated lubricant is smoothly discharged out of the furnace, an airflow flowing system is added to facilitate the removal of part of lubricant sediments which can not be discharged, a collecting port is arranged at the lower part of the furnace bottom to be easily cleaned out of the furnace,

the furnace cover of the pre-sintering area and the flange connection with the sintering area both use bolts, so the detection is simple,

sintering zone

The furnace tube in the sintering area adopts a muffle furnace tube made of heat-resistant cast steel, and the furnace tube is provided with sufficient length, so that the protective atmosphere is stable, the transverse temperature difference on the conveying belt can be controlled within +/-2 ℃,

in order to prevent the dirty shielding gas from flowing into the sintering area when lubricant is removed from the pre-sintering area, a baffle plate is arranged between the pre-sintering area and the sintering area to prevent the gas from flowing in,

the heat insulating material of the furnace tube is made of ceramic fiber except for bearing the gravity of the furnace tube, so that the furnace tube has good heat economy and good heat insulating effect, thereby controlling the surface temperature of the furnace body to be below 60 ℃,

the indirect heating by the SiC heating element can be replaced from the outside, and in addition, each terminal of the heater adopts heat-resistant materials,

slow cooling area

The slow cooling zone adopts natural cooling (air), has sufficient length (1200mm), is insulated by heat-insulating material, has the function of recovering carbon content, and is integrally processed by the same heat-resistant cast steel as the sintering zone,

cooling zone

The cooling area is divided into three sections, the bottom of the first section is processed into a boat shape, the design is to accelerate the flow velocity of water, prevent scale and the like from adhering to block water flow, cause high temperature at the bottom to cause cracking of sintered parts, and each area is provided with a cleaning opening for facilitating cleaning of the scale and the like;

the ball mill in step S3 is composed of a horizontal cylinder, a hollow feeding and discharging shaft, and a grinding head, wherein the cylinder is a long cylinder, the cylinder is filled with a grinding body made of steel plate, the cylinder is fixed with the cylinder by a steel lining plate, the grinding body is generally steel ball, and is filled into the cylinder according to different diameters and a certain proportion, and the grinding body can also be made of steel segments. The material is selected according to the granularity of the grinding material, the material is loaded into the barrel body from the hollow shaft at the feeding end of the ball mill, when the ball mill barrel body rotates, the grinding body is attached to the lining plate of the barrel body and taken away by the barrel body under the action of inertia and centrifugal force and friction force, when the grinding body is taken to a certain height, the grinding body is thrown off under the action of the gravity of the grinding body, and the falling grinding body breaks the material in the barrel body like a projectile body.

The materials are fed into the first bin of the mill by a feeding device through a hollow shaft, and the bin is internally provided with a stepped lining plate or a corrugated lining plate which is internally provided with steel balls of various specifications, and the steel balls are driven to fall down after being driven to a certain height by the centrifugal force generated by the rotation of a cylinder body, so that the materials are impacted and ground. After the material reaches rough grinding in the first bin, the material enters the second bin through the single-layer bin partition plate, the flat lining plate is inlaid in the bin, the steel ball is arranged in the bin, and the material is further ground. Discharging the powder through a discharging grate plate to finish grinding operation;

the main part of the ball mill is composed of a feeding part, a discharging part, a rotary part and a transmission part (a speed reducer, a small transmission gear, a motor and an electric control).

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments or portions thereof without departing from the spirit and scope of the invention.