CN102531563A - Nickel-zinc-magnesium-lanthanum ferrite nano wave-absorbing material and preparation method thereof - Google Patents

Abstract

The invention relates to a nickel-zinc-magnesium-lanthanum ferrite nano wave-absorbing material and a preparation method thereof. The molecular formula of the wave-absorbing material is Zn0.4MgxNi0.6-xLayFe2-yO4, wherein x is more than or equal to 0.1 and less than or equal to 0.3, and y is more than or equal to 0.01 and less than or equal to 0.1. The preparation method comprises two processes of preparing nickel-zinc-magnesium-lanthanum ferrite powder by using a sol-gel method, and calcining the ferrite. The prepared nickel-zinc-magnesium-lanthanum ferrite is a rufous nano wave-absorbing material. The method is simple, energy is saved, and the prepared ferrite material has two intervals for absorbing radar waves in a frequency band of 1-18GHz to realize wide frequency absorption.

Description

A kind of nickel zinc-magnesium lanthanum ferrite nano absorbing material and preparation method thereof

Technical field:

The invention belongs to the material technology field.Be specially a kind of nickel zinc-magnesium lanthanum ferrite nano absorbing material of preparation, be mainly used in the stealthy demand of equipment.

Background technology:

The spinel nickel-zinc ferrite has characteristics such as inexpensive, Heat stability is good, absorption of electromagnetic wave be strong as soft magnetic materials, is one type of radar absorbing that receives people's extensive concern.But deficiencies such as it is narrow also to exist suction ripple frequency range, and sintering temperature is high in the production process, energy consumption is big.It is wide how to prepare the absorption frequency range, is investigation of materials worker's a major issue to the big spinel nickel-zinc ferrite absorbing material of hertzian wave loss.The researchist is devoted to improve the synthesis technique of nickel-zinc ferrite or nickel-zinc ferrite is carried out doping vario-property, widens it and inhales the ripple frequency range.

Patent 02133421.8 discloses the preparation method of high-conductive nickel-zinc ferrite.To ferrite copper doped and manganese, have low mix loss, high reflection loss characteristics.

Patent 00133679.7 discloses the preparation method of self propagating high temperature synthesizing soft magnetic ferrite, carries out the synthetic nickel-zinc ferrite of solid state reaction through the roasting oxidation thing.

Similar techniques also has, but does not still prepare the method for nickel zinc-magnesium lanthanum ferrite nano absorbing material.Magnesium-dopedly in nickel-zinc ferrite help to improve ferritic low frequency wave-sucking performance, realize that wideband inhales ripple; Lanthanum is a kind of REE, and its unpaired electron is shielded by outermost electron, has special electromagnetic performance, has constituted the important foundation of strong absorption, wideband microwave absorbing material, and in addition, lanthanum can also the refinement ferrite crystal grains, helps to prepare nano wave-absorbing material.

Summary of the invention:

A kind of preparation method of nickel zinc-magnesium lanthanum ferrite nano absorbing material comprises two processes, the one, and the preparation of ferrite powder, the 2nd, ferritic calcining.

A kind of nickel zinc-magnesium lanthanum ferrite nano absorbing material, the molecular formula of this absorbing material is: Zn _0.4Mg _xNi _0.6-xLa _yFe _2-yO ₄, wherein, 0.1≤x≤0.3,0.01≤y≤0.1.

According to molar ratio weighing iron nitrate, zinc nitrate, nickelous nitrate, magnesium nitrate, Lanthanum trinitrate, wherein iron nitrate 63～67%, zinc nitrate 13%, nickelous nitrate 10～17%, magnesium nitrate 3～10%, Lanthanum trinitrate 0.3～3% are used deionized water dissolving with nitrate salt;

Mol ratio according to the metals ion sum in Hydrocerol A and the nitrate salt is 1: 1 weighing Hydrocerol A and is dissolved in the deionized water; Citric acid solution is joined in the nitrate soln, leave standstill to the clarification till, regulator solution pH value is 6～7; Continuous stirring solution heats it up to the thickness that becomes then in the constant temperature air dry oven in 70 ℃ of water-bath environment, makes it thorough drying and forms xerogel; Light xerogel and form ferrite powder;

Ferrite powder is put into heat treatment furnace, and in 650～850 ℃ of insulations 2 hours, furnace cooling was to room temperature, and product is a nickel zinc-magnesium lanthanum ferrite nano absorbing material.

The present invention has following meliority owing to adopt technique scheme:

(1) the present invention can accomplish heat treatment process at relatively low sintering temperature, is guaranteeing that energy efficient reduces cost, and helps industrialization promotion under the prerequisite that ferrite performance does not descend.

(2) product granularity is little, can obtain nano level dispersive powder.Because nano-particles size is little, specific surface area is big, can increase the shielding that radar wave is advanced and run in material, improves powder to the absorption of electromagnetic wave ability.

(3) be that the frequency range of 1～18GHz comprises hertzian wave between two uptake zones in frequency, have the wideband absorbing property.

(4) process stabilizing, favorable repeatability.

Description of drawings

Below in conjunction with accompanying drawing the present invention is described further:

Fig. 1 is the nickel zinc-magnesium lanthanum ferrite microscopic appearance photo of the embodiment of the invention 1 preparation.

Fig. 2 is the ferritic x x ray diffration pattern x of nickel zinc-magnesium lanthanum of the embodiment of the invention 1 preparation.

Fig. 3 is the change curve of the ferritic loss tangent of nickel zinc-magnesium lanthanum of the embodiment of the invention 1 preparation with frequency.

Fig. 4 is the change curve of the ferritic loss tangent of nickel zinc-magnesium lanthanum of the embodiment of the invention 2 preparations with frequency.

Embodiment:

Embodiment 1

Weighing Hydrocerol A 252.2 grams, nickelous nitrate 58.2 grams, zinc nitrate 47.5 grams, magnesium nitrate 10.3 grams, Lanthanum trinitrate 1.3 grams, iron nitrate 321.6 grams.Hydrocerol A is dissolved in the beaker with deionized water.With nickelous nitrate, zinc nitrate, magnesium nitrate, Lanthanum trinitrate, iron nitrate are dissolved in another beaker.Citric acid solution is joined in the nitrate soln, and stirring makes it to mix.Mixing solutions is left standstill 12h in room temperature.Adding ammoniacal liquor adjusting pH value to above-mentioned drips of solution is 6.Continuous stirring solution puts it into the heating of constant temperature air dry oven afterwards and makes it thorough drying until forming xerogel till the thickness that becomes in 70 ℃ of water-bath environment.Take out xerogel samples and grind and in air, light, obtain black nickel zinc-magnesium lanthanum ferrite powder.With nickel zinc-magnesium lanthanum ferrite powder in the van-type resistance furnace in 850 ℃ of insulations 2 hours and furnace cooling, finally obtain sorrel nickel zinc-magnesium lanthanum ferrite.Can see that by Fig. 1 the prepared ferritic grain-size of nickel zinc-magnesium lanthanum is uniformly dispersed, and does not have tangible agglomeration in 100nm.Can know that by Fig. 2 the ferrite of present embodiment preparation is a spinel structure.The loss tangent of material is to estimate the important evidence of Ferrite Material to the absorption of electromagnetic wave performance, and it is defined as:

$\tan {\mathrm{\δ}}_m=\frac{{\mathrm{\μ}}^{\′\′}}{{\mathrm{\μ}}^{\′}}---\left(1\right)$

$\tan {\mathrm{\δ}}_e=\frac{{\mathrm{\ϵ}}^{\′\′}}{{\mathrm{\ϵ}}^{\′}}---\left(2\right)$

(1) formula is called the magnetic loss factor and the electrical loss factor respectively with (2) formula.The size of loss tangent has been reacted the drain performance of material and the relation between its electromagnetic parameter.Energy waste is to be controlled by the imaginary part existence of absorbing material specific conductivity and magnetic permeability.The loss size can the electricity consumption dissipation factor and magnetic loss factor characterize.δ _eAnd δ _mBe called electrical loss angle and magnetic loss angle respectively.The imaginary part of material magnetic permeability and specific conductivity and tan δ are big more, and absorbing property is good more.According to Fig. 3, present embodiment two absorption of electromagnetic wave intervals occurred at 1～18GHz, shows that prepared nickel zinc-magnesium lanthanum Ferrite Material has the wideband absorbing property.

Embodiment 2

Weighing Hydrocerol A 252.2 grams, nickelous nitrate 34.9 grams, zinc nitrate 47.5 grams, magnesium nitrate 30.8 grams, Lanthanum trinitrate 13 grams, iron nitrate 307.0 grams.Hydrocerol A and nitrate salt are dissolved in respectively in two beakers with deionized water, join citric acid solution in the nitrate soln, stirring makes it to mix, and afterwards solution is left standstill 12h at room temperature.Dropping ammonia adjusting pH value is 7 in above-mentioned solution.Continuous stirring solution puts it into the heating of constant temperature air dry oven afterwards and makes it thorough drying, until forming xerogel till the thickness that becomes in 70 ℃ of water-bath environment.Take out xerogel samples and grind and in air, light, obtain black nickel zinc-magnesium lanthanum ferrite powder.With nickel zinc-magnesium lanthanum ferrite powder in the van-type resistance furnace in 650 ℃ of insulations 2 hours and furnace cooling, finally obtain sorrel nickel zinc-magnesium lanthanum ferrite nano absorbing material.

Claims (2)

1. nickel zinc-magnesium lanthanum ferrite nano absorbing material, the molecular formula of this absorbing material is: Zn _0.4Mg _xNi _0.6-xLa _yFe _2-yO ₄, wherein, 0.1≤x≤0.3,0.01≤y≤0.1.

2. as claimed in claim a kind of preparation method of nickel zinc-magnesium lanthanum ferrite nano absorbing material; It is characterized in that: according to molar ratio weighing iron nitrate, zinc nitrate, nickelous nitrate, magnesium nitrate, Lanthanum trinitrate; Wherein iron nitrate 63～67%, zinc nitrate 13%, nickelous nitrate 10～17%, magnesium nitrate 3～10%, Lanthanum trinitrate 0.3～3% are used deionized water dissolving with nitrate salt;

Mol ratio according to the metals ion sum in Hydrocerol A and the nitrate salt is 1: 1 weighing Hydrocerol A and is dissolved in the deionized water; Citric acid solution is joined in the nitrate soln, leave standstill to the clarification till, regulator solution pH value is 6～7; Continuous stirring solution heats it up to the thickness that becomes then in the constant temperature air dry oven in 70 ℃ of water-bath environment, makes it thorough drying and forms xerogel; Light xerogel and form ferrite powder;

Ferrite powder is put into heat treatment furnace, and in 650～850 ℃ of insulations 2 hours, furnace cooling was to room temperature, and product is a nickel zinc-magnesium lanthanum ferrite nano absorbing material.

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