High additivity ferrite in manganese zinc series and preparation method thereof
Technical field
The present invention relates to a kind of Mn-Zn based ferrite and preparation method thereof, relate in particular to and a kind ofly (have ferrite in manganese zinc series of lower power loss and excellent DC stacked performance and preparation method thereof under the 10KHz~100KHz) at low frequency.
Background technology
The ferrite of soft magnetism has the magnetic core that quite high magnetic permeability is used as inductive elements such as transformer, inducer, wave filter, high-performance power switch because of it, and its demand is with increasing.On the one hand, fast development along with the information industry technology, the technical requirements of electronics and index are updated and are upgraded, and the switch of electronics and calculating, processing speed are more and more faster, and soft magnetic ferrite exists magnetic hysteresis loss, eddy-current loss and residual loss etc. after the match at alternating electromagnetism; On the other hand, in some circuit, electron device often need be worked under certain dc state, for example line output transformer, high-frequency transformer and smoothing choke coil etc.Under these situations,, also needed to have good dc superposition characteristic, promptly under the stack direct current biasing, required the reversible permeaability fall of magnetic core little except requiring magnetic core to have the good electromagnetic property.At present, for a lot of magnetic cores such as U type, EC type, all proposed the superimposed characteristics requirement under certain galvanic current, and required more and more higher.At present, the HV45 material of TDK company can satisfy the requirement of this respect preferably, however the domestic material require that rarely has producer can produce this material and satisfy this respect.
In similar the problems referred to above field, it is that 03115906.0 Chinese patent application file discloses a kind of manganese-zinc power soft ferrite material powder and preparation method thereof, Fe in the soft magnetic ferrite material powder that the patent No. is arranged
2O
3Be 58-79wt%, Mn
3O
4: 15-30wt%, ZnO:5-15wt%, auxiliary material (comprises SiO
2, CaCO
3, V
2O
5, Nb
2O
5): 0-7wt%, total amount satisfies 100%.Major ingredient and auxiliary material are made manganese-zinc power soft ferrite material powder by mixing, pre-burning, coarse reduction, sand milling, five operations of mist projection granulating, it is said that its finish mix powder power consumption is lower, saturation induction density Bs height.
The patent No. that also has similarly is that 02150733.3 Chinese patent application file also discloses a kind of high frequency close grain soft magnetic ferrimagnetics material and production technique thereof, it is that main raw material is made by ferric oxide, zinc oxide and manganese oxide, the average grain size that it is characterized in that described soft magnetic ferrite is 3-5 μ m, and each component in the weight percentage ranges of oxide compound is: Fe
2O
3: 50-57%; ZnO:0-13%; MnO:30-50%; All the other are doping composition M; Its processing step that adopts is: batching, ball milling, vibration, pre-burning, sand milling, granulation, moulding, sintering, mill processing and packing, it is said: its technology is fit to industrialized mass production, the characteristics that production cost is low, process stabilizing, product have the magnetic permeability height, power loss is little, reach the technical indicator of high-frequency low-consumption power Ferrite Material PC50, thereby provide advantageous conditions for miniaturization, the chip type of realizing electron device.
Similarly, also having publication number is that the Japanese patent application file of JP2001068326 also discloses a kind of high magnetic permeability, low-loss and has been used for the Mn-Zn ferrite of transformer aspect, it adopts the auxiliary material that comprises nickel oxide, and the proportioning of major ingredient and content are also different, do not give unnecessary details.
Summary of the invention
The technical purpose that the present invention will reach be to provide a kind of power loss lower, be suitable for high additivity ferrite in manganese zinc series and manufacture method thereof as device magnetic cores such as good line output transformer of DC stacked performance and smoothing choke coils.
For this reason, technical solution of the present invention is a kind of high additivity ferrite in manganese zinc series, this ferrite comprises principal constituent ferric oxide, zinc oxide and manganese oxide and ancillary component, described principal constituent and ancillary component sintering form face-centred cubic spinel crystal structure, and described principal constituent is as follows in the content of standard substance separately, Fe
2O
3: 51%~56mol%, MnO:34mol%~40mol%, ZnO:6mol%~12mol%, described ancillary component comprises calcium oxide, potassium oxide and titanium oxide, described calcium oxide, potassium oxide and titanium oxide are with its standard substance CaO, K
2O and TiO
2The total content of meter is 0.01~0.92wt%.The present invention is according to the crystallography principle, adopt the auxiliary material of experiment discovery and the special collocation of major ingredient, induce and impel the spinel internal structure evenly, lattice imperfection and pore be less, reduced the resistance of domain wall motion, the magnetic hysteresis loss of material diminishes, thereby the reversible magnetization stage in the magnetic core magnetic history is prolonged, postponed the convergence of saturation magnetization, thereby improved the dc superposition characteristic of magnetic core.80% of core loss comes from magnetic hysteresis loss under the low frequency, and this powder has low power loss when 10~100KHz.
And high stack performance manganese of the present invention-zinc power ferrite material powder has good processability.Material powder physicals is as follows:
The particulate water content is 0.2~0.6wt%,
The pine dress is than being: 1.25~1.45g/cm
3,
Angle of repose is≤30 °.
Described relatively principal constituent total amount, described ancillary component is respectively CaO:0.002~0.12wt%, TiO in the content of standard substance separately
2: 0.005~0.4wt%, K
2O:0.003~0.4wt%.Mentioned component is preferably CaO:0.0028~0.056wt%, TiO respectively
2: 0.005~0.3wt%, K
2O:0.0034~0.4wt%.
In order to strengthen above-mentioned advantage of the present invention, as the good embodiment of practicality of the present invention, described ancillary component further comprise Si oxide, barium oxide, niobium oxide, cobalt/cobalt oxide, Zirconium oxide wherein one or more, described relatively principal constituent total amount, these ancillary components are with its standard substance SiO
2, V
2O
5, Nb
2O
5, Co
2O
3, ZrO
2The total content of meter is 0~0.515wt%.
The described relatively principal constituent total amount of Si oxide, barium oxide, niobium oxide, cobalt/cobalt oxide, Zirconium oxide in the described ancillary component is separately with its standard substance SiO
2, V
2O
5, Nb
2O
5, Co
2O
3, ZrO
2The content of meter is respectively SiO
2: 0~0.015wt%, V
2O
5: 0~0.1wt%, Nb
2O
5: 0~0.1wt%, Co
2O
3: 0~0.2wt%, ZrO
2:: 0~0.1wt%.
Correspondingly, the manufacture method that another correlation technique solution of the present invention is a kind of aforesaid high additivity ferrite in manganese zinc series, this method comprises the steps: A) with principal constituent Fe
2O
3, Mn
3O
4, the ZnO pellet mixes through a sand milling, making median size is the principal constituent powder of 1.0 ± 0.3 μ m; B) with described principal constituent powder drying, pre-burning, add pure water, dispersion agent and ancillary component again, carry out the secondary sand milling together, adding tackiness agent and defoamer in the secondary sand grinding process, to make median size be 1.0 ± 0.2 μ m mixed powders; C) with mixed powder drying, compression moulding, under 1300~1400 ℃ of following inflated with nitrogen atmosphere, be incubated 4~7 hours sintering, cooling makes described ferrite finished product under balanced atmosphere.Method of the present invention and production cost are lower, be applicable to common big industrial production, the magnetic core that utilizes the present invention to make has good stack performance, have low power loss, high saturation induction density and high Curie temperature under low frequency, the 100KHz power loss also can be equivalent to the material of the PC40 of TDK company class under the high frequency.
As the preferred embodiment of the inventive method, among the step B of the present invention, described defoamer comprises n-Octanol, and described tackiness agent comprises polyvinyl alcohol.
Among the described step B, described relatively principal constituent total amount, the adding proportion of described pure water are 35~38wt%, and the adding proportion of described dispersion agent is 0~1.0wt%, the adding proportion of described tackiness agent is 0.4~1.0wt%, and the adding proportion of described defoamer is 0~0.5wt%.
Among the described step B, described calcined temperature is controlled at 890 ℃ ± 20 ℃ scopes, and in the pre-burning process, the magnetization degree of described principal constituent powder is controlled in 0~25 scope.
Among described step B, the C, described drying process is to adopt spray method; Among the described step C, the density of the green compact after the described compression moulding is 3.0 ± 0.2g/cm
3
The invention will be further described below in conjunction with specific embodiment.
Embodiment
Embodiment 1
Take by weighing 53.4mol%Fe
2O
3, (the raw material form is Mn to 38.6mol%MnO
3O
4), 7.9mol%ZnO, wherein iron oxide red adopts homemade Baosteel iron oxide red (Fe
2O
3% 〉=99.2%), Mn
3O
4Adopt gold auspicious common (Mn% 〉=71%), ZnO producer is capital, Shanghai (ZnO% 〉=99.7%).Drop in the sand mill and stir, the control median size is 1.0 ± 0.3 μ m, and once spraying back electricity consumption heating revolving kiln under 890 ± 20 ℃ of temperature carries out pre-burning, and the control magnetization degree is 0~25.Pre-subsequently imitation frosted glass drops into sand mill and carries out the secondary sand milling, and described relatively principal constituent total amount in the sand grinding process adds pure water 37%, dispersion agent 0.01% and defoamer 0.008%, and adds addition of C aCO
30.06wt%, K
2CO
30.06wt%, V
2O
50.05wt%, Nb
2O
50.05wt%, Co
2O
30.04wt%, TiO
20.15wt% makes the mixed powder that median size is 1.0 ± 0.2 μ m.Carry out the secondary mist projection granulating at last and obtain Mn-Zn ferrite particle material powder.
Get the toroidal core of this particulate material moulding compacting φ 25mm * φ 15mm * 7.5mm, compact density is 3.0 ± 0.2g/cm
3Get this particulate material moulding and be pressed into U type green compact (foreign minister 38.3 ± 0.6mm, overall height 33.6 ± 0.3mm, bottom width 13.0 ± 0.3mm, the minimum 14.1mm of home record, interior dark 23.0 ± 0.2mm, wide 10.7 ± the 0.2mm of side's leg, body diameter 13.0 ± 0.3mm) products, the product stack performance of this model has high requirement to powder and technology.At 1300~1400 ℃ of following N
2Carry out sintering under the protection, be incubated 4~7 hours, under balanced atmosphere, cool off, process at grinding machine again.
Embodiment 2
Take by weighing 52.9mol%Fe
2O
3, (the raw material form is Mn to 37.9mol%MnO
3O
4), 9.1mol%ZnO, drop in the sand mill and stir, the control median size is 1.0 ± 0.3 μ m, once spraying back electricity consumption heating revolving kiln under 890 ± 20 ℃ of temperature carries out pre-burning, the control magnetization degree is 0~25.Pre-subsequently imitation frosted glass drops into sand mill and carries out the secondary sand milling, and described relatively principal constituent total amount in the sand grinding process adds pure water 37%, dispersion agent 0.01% and defoamer 0.008%, and adds additive SiO
20.002wt%, CaCO
30.04wt%, K
2CO
30.4wt%, V
2O
50.04wt%, Nb
2O
50.05wt%, TiO
20.15wt%, ZrO
20.05wt%, the median size of control secondary sand milling is 1.0 ± 0.2 μ m.Carry out the secondary spraying at last and obtain Mn-Zn ferrite particle material powder.
Get the toroidal core of this particulate material moulding compacting φ 25mm * φ 15mm * 7.5mm, compact density is 3.0 ± 0.2g/cm
3Get this particulate material moulding compacting U type green compact (foreign minister 38.3 ± 0.6mm, overall height 33.6 ± 0.3mm, bottom width 13.0 ± 0.3mm, the minimum 14.1mm of home record, interior dark 23.0 ± 0.2mm, the wide 10.7 ± 0.2mm of square leg, body diameter 13.0 ± 0.3mm) products, the product stack performance of this model has high requirement to powder and technology, at 1300~1400 ℃ of following N
2Carry out sintering under the protection, be incubated 4~7 hours, under balanced atmosphere, cool off, process at grinding machine again.
Grinding the BHS-4 tester with the U.S.'s 2330 power consumption instrument, Japan reason, to record the correlated performance of the annular of embodiment 1,2 and U type sintered compact as shown in table 1; The U type sintered compact stack performance that records embodiment 1,2 with HP4284A inductance stack tester is as shown in table 2.
Table 1
Lot number | Initial permeability | Saturation induction density Bs (H=1194A/m) | Power loss mw/g (100 ℃) |
??16KHz | ??64KHz | ??100KHz |
??TDK?HV45 | ????2300 | ????500 | ??3 | ????40 | ????90 |
Embodiment 1 | ????2284 | ????516 | ??2.95 | ????38.7 | ????73.2 |
Embodiment 2 | ????2315 | ????512 | ??3.05 | ????41.2 | ????75.6 |
Table 2
Lot number | Superimposed current I=1.5A (1KHz, 0.3V) | Superimposed current I=1.7A (1KHz, 0.3V) |
100 ℃, φ 0.3 * 112Ts * 2, air gap delta=0.4mm * 2 | 100 ℃, φ 0.3 * 112Ts * 2, air gap delta=0.4mm * 2 |
????L
0 | ?????L | ?????L/L
0 | ????L
0 | ?????L | ????L/L
0 |
Embodiment 1 | ????3.15 | ????2.780 | ????88.25% | ????3.15 | ??2.6675 | ?84.67% |
Embodiment 2 | ????3.20 | ????2.795 | ????87.34% | ????3.20 | ??2.68 | ?83.75% |
By table 1 and table 2 as seen, manganese-zinc ferrite magnetic core product power loss of the present invention lower, have initial permeability, saturation induction density and a DC stacked performance preferably.