CN1721563A - Fe-based amorphous alloy ribbon - Google Patents

Abstract

An Fe-based amorphous alloy ribbon having a composition comprising Fe<SUB>a</SUB>Si<SUB>b</SUB>B<SUB>c</SUB>C<SUB>d </SUB>and inevitable impurities, wherein a is 76 to 83.5 atomic %, b is 12 atomic % or less, c is 8 to 18 atomic %, and d is 0.01 to 3 atomic %, the concentration distribution of C measured radially from both surfaces to the inside of said Fe-based amorphous alloy ribbon having a peak within a depth of 2 to 20 nm.

Description

The Fe based amorphous alloy band

Technical field

The present invention relates to a kind of Fe based amorphous alloy band, it has high magnetic flux density and low core loss, is suitable for transformer, engine, generator and reactance coil, Magnetic Sensor etc.

Background technology

The Fe based amorphous alloy band is because excellent soft magnetic property, particularly low core loss, thereby the magnetic core of using it for transformer has caused the great interest of people.Especially the non-crystalline state Fe-Si-B alloy band that has high magnetic flux density BS and superior heat-stability is used to the magnetic core of transformer.But the Fe based amorphous alloy band is not so good as the current siliconized plate that is used as magnetic core of transformer usually aspect saturation magnetic flux density.Therefore, people have begun to develop research, so that the Fe with high saturation magnetic flux density to be provided based amorphous alloy band.In order to improve saturation magnetic flux density, people have carried out various trials: increase the Fe quantity that magnetization is worked; Wait the decline that compensates the thermostability that causes owing to the increase of Fe amount by adding Sn, S; And adding C.

JP 5-140703 A discloses a kind of non-crystalline state Fe-Si-B-C-Sn alloy with high saturation magnetic flux density, wherein makes the alloy amorphous attitudeization of high Fe-content with Sn.JP 2002-285304 A discloses a kind of non-crystalline state Fe-Si-B-C-P alloy with high saturation magnetic flux density, wherein the alloy amorphous attitudeization that Fe content is sharply increased with P.

Importantly: the magnetic core of practical application also has high magnetic flux density under downfield, promptly high squareness ratio B₈₀/ B_S, B wherein₈₀Magneticflux-density in the expression 80A/m magnetic field.For magnetic core of transformer, in fact importantly transformer is worked under high magnetic flux density.The work magneticflux-density is definite by the relation between magneticflux-density and the core loss, and the magneticflux-density should be lower than core loss and significantly increase the time.Even saturation magnetic flux density is identical, B₈₀/ B_SLow Fe based amorphous alloy band also can increase in high work magneticflux-density lower core loss.In other words, has higher B in the high magnetic flux density district₈₀The Fe based amorphous alloy band of lower core loss can be worked under higher work magneticflux-density.But, B₈₀The Fe based amorphous alloy band that surpasses 1.55T does not also drop at present to be produced in batches.Its reason is: if contain the Fe that surpasses 81 atom % in the alloy band of high saturation magnetic flux density, then they can can't stably be produced in batches because surface crystallizationization and thermostability descend.In order to solve this difficult problem, people have attempted waiting and improving surface crystallizationization and thermostability by adding Sn, S.Although these methods can be improved alloy property, being with of gained is frangible, and can't produce the equally distributed band of additive continuously.Therefore, this amorphous alloy band can't be produced in batches.Although Fe content is containing the C alloy and can producing their B in batches of 81 atom %₈₀Be 1.55T or following.In addition, it is that Fe content is the serious problems that 81 atom % or following Fe based amorphous alloy band exist that embrittlement, surface crystallizationization and thermostability descend.Can improve saturation magnetic flux density although add C and P, the band of gained is very frangible and can't easily they be formed transformer.

As mentioned above, although carried out effort to improving Fe based amorphous alloy band saturation magnetic flux density, but owing to degradation reason under embrittlement, surface crystallizationization and the squareness ratio, up to the present can't stably produce the Fe based amorphous alloy band that meets following requirement: the B that described Fe based amorphous alloy band is measured on annular core₈₀For 1.55T or more than, and core loss W_14/50For 0.28W/g or more than.

Summary of the invention

Goal of the invention

Therefore, an object of the present invention is to provide a kind of Fe based amorphous alloy band with high saturation magnetic flux density and low core loss, this Fe based amorphous alloy band is by control Si and the weight ratio of C and the roughness of roll surface in contact, and control the scope and the peak value of the C-segregation layer of free surface and roll surface in contact by the gas volume that is blown on the roll, thereby make it have high B₈₀/ B_S, excellent thermostability, and reduce embrittlement.

Summary of the invention

Fe based amorphous alloy band of the present invention has the Fe of comprising_aSi_bB_cCd and unavoidable impurities are formed, wherein a is 76 to 83.5 atom %, b is 12 atom % or following, c is 8 to 18 atom %, d is 0.01 to 3 atom %, has peak value to the C concentration distribution that its inner radial measures from two surfaces of Fe based amorphous alloy band in the degree of depth 2 to 20nm scopes.That is, C-segregation layer is arranged at each free surface and dark 2 to the 20nm places of roll surface in contact of distance Fe based amorphous alloy band.

More preferably a is 80 to 83 atom %, and b is 0.1 to 5 atom %, and c is 12 to 18 atom %, and d is 0.01 to 3 atom %, and a, b and d satisfy condition: b≤(0.5 * a-36) * d^1/3, like this Fe based amorphous alloy band after annealing, saturation magnetic flux density B_SFor 1.6T or more than, and magneticflux-density B₈₀For 1.55T or more than.

The annular core that constitutes by Fe based amorphous alloy band of the present invention, after annealing, the preferred core loss W under 1.4T magneticflux-density and 50Hz frequency_14/50Be 0.28W/kg or following.

Preferred Fe based amorphous alloy band of the present invention the breaking strain ε after the annealing be 0.02 or below.Breaking strain ε is calculated by ε=t/ (2r-t), wherein t represent with thickness, and r represent in the pliability test with radius of rupture.As shown in Figure 6, pliability test is performed such: thealloy band 10 of bending is placed between the pair ofparallel plate 20,21, make two part keeping parallelisms (180 °) ofalloy band 10, level reduces theupper plate 20 of parallel plate,alloy band 10 is bent to a littler angle gradually, the distance D when 10 fractures of alloy band between twoplates 20,21 of (as 12 indications) measurement (=2r).If the alloy band can be bent to 180 °, then ε=1.

Can be prepared as follows the Fe based amorphous alloy band: the CO or the CO that in castingprocesses, on roll, blow pre-determined quantity₂Gas, the average surface roughness Ra that makes Fe based amorphous alloy band and roll surface in contact are 0.6 μ m or following.Average surface roughness Ra be five data of the surfaceness measured with profilograph carry out arithmetical mean and.

Description of drawings

Figure 1 shows that C segregation layer depth can be with blowing the synoptic diagram that tolerance changes;

Figure 2 shows that the stress pine executes the graphic representation with breaking strain and C and Si concentration relationship;

Fig. 3 is the synoptic diagram that the stress pine is executed the rate measuring method;

Figure 4 shows that the concentration of sample 1 various elements and apart from the graphic representation of the depth relationship of roll surface in contact;

Figure 5 shows that the concentration of sample 8 various elements and apart from the graphic representation of the depth relationship of roll surface in contact;

Fig. 6 is the synoptic diagram of breaking strain measuring method.

DESCRIPTION OF THE PREFERRED

The amount a of Fe is 76 to 83.5 atom %.When Fe measured less than 76 atom %, the Fe based amorphous alloy band did not possess as the required enough big saturation magnetic flux density B of magnetic core_SOn the other hand, when it surpassed 83.5 atom %, the thermostability of Fe based amorphous alloy band descended, so that can't carry out stably manufactured.In order to obtain high saturation magnetic flux density, preferred a is 80 to 83 atom %.50 atom % or following Fe can replace with Co and/or Ni.In order to obtain high saturation magnetic flux density, the replacement amount of preferred Co is 40 atom % or following, and the replacement amount of Ni is 10 atom % or following.

Si is the element that makes alloy amorphous attitudeization.In order to have the saturation magnetic flux density of raising B_S, the amount b of Si is 12 atom % or following.In order to obtain higher saturation magnetic flux density B_S, preferred b is 0.1 to 5 atom %.

B is to the maximum element of alloy amorphous material contribution.The amount c of B is 8 to 18 atom %.As the amount c of B during less than 8 atom %, the thermostability of gained Fe based amorphous alloy band descends.On the other hand, even it surpasses 18 atom %, the amorphous material of alloy there is not bigger effect yet.In order to obtain having high saturation magnetic flux density B_SWith the Fe based amorphous alloy band of thermostability, the amount c of preferred B is 12 to 18 atom %.

C improves squareness ratio and high saturation magnetic flux density B_SElement.The amount d of C is 0.01 to 3 atom %.As d during, can't obtain enough effects less than 0.01 atom %.On the other hand, when it surpassed 3 atom %, the decline of embrittlement and thermostability appearred in the Fe based amorphous alloy band of gained.The amount d of preferred C is 0.05 to 3 atom %.

At least a element that is selected from Cr, Mo, Zr, Hf and Nb that can contain 0.01 to 5 atom % in the alloy, and 0.5 atom % or the following at least a unavoidable impurities that is selected from Mn, S, P, Sn, Cu, Al and Ti.

The invention solves in the Fe based amorphous alloy band by improving saturation magnetic flux density B_SAnd the problem that the embrittlement that causes, surface crystallizationization and squareness ratio descend.Can adopt several different methods to improve the saturation magnetic flux density B of Fe based amorphous alloy band_SBut, when using the Fe based amorphous alloy band, also should solve problems such as squareness ratio, embrittlement, surface crystallizationization simultaneously as the magnetic core of transformer etc.

The adding of C has increased saturation magnetic flux density B_S, fluidity of molten and with the wetting properties of roll.Therefore but the adding of C has produced C segregation layer, causes embrittlement and thermolability, higher core loss under high magnetic flux density.So, specially do not add C in actual applications., found that in the distribution of near surface dependency by research C, can provide to have high B by control C and the weight ratio of Si and the scope and the peak value of C-segregation layer to the C add-on₈₀/ B_S, low core loss and reduce the Fe based amorphous alloy band of embrittlement and thermolability.

The formation of C-segregation layer causes at low temperatures nearly surface the stress pine to occur executing, and is effective especially when this Fe based amorphous alloy band of naming a person for a particular job is wrapped on the annular core.High stress pine is executed rate and causes high B₈₀/ B_S, thereby be reduced in core loss under the high magnetic flux density.Importantly when the peak concentration of C is present in the surperficial controlled range of distance, can obtain this effect.

If because pore etc. makes surfaceness big, then thickness of oxide layer is inhomogeneous, cause the C-segregation layer depth and the scope that produce inhomogeneous.It is inhomogeneous to make the stress pine execute like this, partly produces frangible part.Because in the C-segregation layer that surface irregularity and thermal conductivity reduce, the surface crystallization acceleration, thus reduced B₈₀/ B_STherefore, control surface roughness and evenly forming C-segregation layer in the depth range importantly apart from the surface.In castingprocesses, blow CO or CO with predetermined flow velocity to the alloy melt that is ejected on the roll₂Gas can reach this purpose.

Flow velocity that should pilot-gas is positioned at apart from the scope on surface 2 to 20nm the C-segregation layer of formation.Fig. 1 has schematically shown the amount of gas that is blown on the roll and the relation between spraying pressure and the C-segregation layer scope.When changing gas injection pressure when regulating the width of Fe based amorphous alloy band, the optimal number of institute's blow gas also changes.Therefore, the scope that should consider C-segregation layer is determined the blow gas amount.When blow gas amount very little the time, can't effectively reduce the surfaceness of Fe based amorphous alloy band, cause that C-segregation course is inner to be shifted and in uneven thickness.On the other hand, the stirring of too many gases affect alloy melt, thus make C-segregation layer because contained gas and in uneven thickness and shift to inside also can make the edge variation of band etc.Therefore, importantly blow the gas of optimal number.Control blows tolerance and has reduced surfaceness significantly, thereby produces the C-segregation layer with homogeneity range, and the stress pine that makes the Fe based amorphous alloy band have improvement is executed rate and squareness ratio B₈₀/ B_S, and the annular core loss is reduced, suppress surface crystallizationization and embrittlement.Make the adding of C play abundant effect like this.

The weight ratio of control surface condition and Si and C can obtain better result.Although b and d change with C quantity,, generally can obtain better effect when b/d ratio hour.Fig. 2 has shown that the amount of C, Si and stress pine execute the relation between rate and the maximum strain (breaking strain).In the Fe based amorphous alloy band that contains 82 atom %Fe, as b≤5 * d^1/3The time, the stress pine execute rate be 90% or more than.This is because when the minimizing of the constant and Si quantity of C quantity, the peak value height of C-segregation layer.Therefore, recently regulating the C concentration peak by the weight of control Si and C can change the stress pine and execute rate.When d is 3 atom % or when following, the Fe based amorphous alloy band has heavily stressed pine and executes rate and saturation magnetic flux density, is suitable for the magnetic core of transformer most.And embrittlement, surface crystallizationization and thermostability descend, and the phenomenon that these occur when adding a large amount of C can be inhibited.

With reference to embodiment the present invention is explained in more detail below, but the present invention is not limited by these embodiment.

Embodiment

Embodiment 1

200g is consisted of Fe₈₂Si₂B₁₄C₂Alloy in high-frequency furnace, melt, by the smelting furnace nozzle ejection to 25 to 30m/s the rotation the copper rolls on, blow CO from the nozzle back simultaneously₂Gas produces width and is respectively the Fe based amorphous alloy band that 5mm, 10mm and 20mm and thickness are 23 to 25 μ m.Each Fe based amorphous alloy band is that 2 to 20nm place has C-segregation layer at the distance case depth.For core loss is minimized, the Fe based amorphous alloy band is annealed down at 300 to 400 ℃.Change and blow CO₂The speed of gas is measured the character of Fe based amorphous alloy band.The results are shown in Table 1.

On the monolithic sample, measure B_SAnd B₈₀, and on the annular core of making by the Fe based amorphous alloy band of external diameter 25mm and internal diameter 20mm, measure core loss W_13/50And W_14/50, W wherein_13/50Be the core loss under 1.3T magneticflux-density, 50Hz frequency, W_14/50Be the core loss under 1.4T magneticflux-density, 50Hz frequency.

As shown in Figure 3, will cut into length separately is 10.5 (π R₀) to be wrapped in diameter be R for the Fe basedamorphous alloy band 10 of cm₀On the silica tube 11 of cm, form the monolithic sample, and with above-mentioned identical condition under anneal the stress that produces when forming ring to discharge.Measure with 11 that take off from silica tube, with sample 10 ' the corresponding circular diameter R of C shape₁, determine that by following formula the stress pine executes rate R_S: R_S=(R₀/ R₁) * 100[%], as a parameter of the stress levels of representing to discharge by annealing (heat treated).The stress pine is executed rate R_SBe 100% to mean that promptly stress is discharged fully.

Breaking strain ε calculates by following formula: ε=t/ (2r-t), wherein t represent with thickness, r represents the radius of rupture in the pliability test.

C-segregation floor district is defined as the zone that C concentration is higher than the interior region with even C concentration, is to analyze the roll surface in contact of each sample and definite by Auger electron spectrum.The highest point of C concentration is considered to the peak in the C-segregation layer.

Use available from Horiba, the glow discharge light emission spectrometer (GD-OES) of Ltd. to the roll surface in contact of sample 1 in the enterprising row element analysis of depth direction.The results are shown in Figure 4.

For measure surface roughness, each Fe based amorphous alloy band is cut into the rectangle that 5mm is wide and 12cm is long, and with annealing with above-mentioned identical method.The surfaceness that records is carried out arithmetical mean.The average surface roughness Ra of sample 1 to 3 is 0.35.

Table 1

Sample No.	Width (mm)	B80 [T]	BS [T]	B80/BS (×100％)	Rs (％)
						1	5	1.646	1.669	98.6	95
2	10	1.642	1.665	98.6	96
						3	20	1.638	1.663	98.5	95

Table 1 (continuing)

Sample No.	Breaking strain ε	C-segregation layer scope (nm)	C concentration peak (atom %)	W13/50 (W/kg)	W14/50 (W/kg)
						1	0.048	5-16	3.2	0.152	0.227
2	0.030	5-16	3.0	0.159	0.239
						3	0.025	6-18	2.8	0.157	0.247

Comparative example 1

Under the condition identical, just reduce CO with embodiment 1₂Gas blow tolerance, will go out by nozzle ejection with embodiment 1 identical alloy melt, produce width and be respectively the Fe based amorphous alloy band that 5mm, 10mm and 20mm and thickness are 23 to 25 μ m.The Fe based amorphous alloy band of gained (sample 4 to 6) has C-segregation layer in the place that surpasses 2 to 20nm depth rangees.The character of sample 4 to 6 sees Table 2.The average surface roughness Ra of sample 4 to 6 is 0.78.Although sample 4 to 6 is at W_13/50Aspect and sample 1 to 3 are comparable, but at W_14/50The aspect, sample 4 to 6 is bigger more than the 0.05W/kg than sample 1 to 3.And the breaking strain ε of sample 4 to the 6 also breaking strain than sample 1 to 3 is low.Because surface irregularity, the C-segregation layer of sample 4 to 6 is uneven, causes its character variation.

Table 2

Sample No.	Width (mm)	B80 [T]	BS [T]	B80/BS (×100％)	Rs (％)
						4	5	1.605	1.661	96.6	92
5	10	1.597	1.658	96.3	89
						6	20	1.598	1.659	96.3	90

Table 2 (continuing)

Sample No.	Breaking strain ε	C-segregation layer scope (nm)	C concentration peak (atom %)	W13/50 (W/kg)	W14/50 (W/kg)
						4	0.034	7-23	2.6	0.162	0.293
5	0.019	7-24	2.3	0.168	0.325
						6	0.017	8-24	2.4	0.166	0.319

Embodiment 2

Adopt the mode identical, 200g is had the alloy melt rapid quenching of composition as shown in table 3, form the Fe based amorphous alloy band of wide 5mm and thick 23 to 25 μ m with embodiment 1.The character of each Fe based amorphous alloy band sees Table 3.B₈₀High Fe based amorphous alloy band can keep low core loss under the high workload magneticflux-density.Begin in the enterprising row element analysis of its depth direction from the roll surface in contact of sample 8.The result as shown in Figure 5.The average surface roughness Ra of sample 7 to 22 is 0.38.

Table 3

Sample No.	Form						B80 [T]	BS [T]	B80/BS (×100％)
										Fe	Co	Ni	Si	B	C
	7	78.0	-	-	11.0	12.9										0.1	1.461	1.550	94.3
8							80.0	-	-	9.0	10.9	0.1	1.485	1.570	94.6
	9	81.0	-	-	5.0	13.0										1.0	1.598	1.619	98.7
10							82.0	-	-	2.0	16.0	0.05	1.609	1.632	98.6
	11	82.0	-	-	0.1	17.8										0.1	1.625	1.655	98.2
12							82.0	-	-	1.0	16.9	0.1	1.635	1.665	98.2
	13	82.0	-	-	2.0	15.9										0.1	1.615	1.643	98.3
14							82.0	-	-	1.0	16.0	1.0	1.640	1.661	98.7
	15	82.0	-	-	3.0	14.0										1.0	1.638	1.659	98.7
16							82.0	-	-	4.0	13.0	1.0	1.614	1.656	97.5
	17	82.0	-	-	0.1	15.9										2.0	1.639	1.666	98.4
18							82.0	-	-	4.0	12.0	2.0	1.618	1.658	97.6
	19	82.0	-	-	5.0	10.0										3.0	1.601	1.641	97.6
20							82.0	-	-	6.0	10.0	2.0	1.600	1.631	98.1
	21	82.0	-	-	6.0	11.0										1.0	1.597	1.632	97.9
22							83.0	-	-	3.0	13.0	1.0	1.600	1.629	98.2
	23	80.0	2.0	-	2.0	16.0										0.1	1.656	1.689	98.0
24							80.0	-	2.0	2.0	16.0	0.1	1.633	1.665	98.1

Table 3 (continuing)

Sample No.	Rs (％)	Breaking strain ε	C-segregation layer scope (nm)	C concentration peak (atom %)	W13/50 (W/kg)	W14/50 (W/kg)
							7	82	0.020	6-19	0.6	0.165	0.297
8	86	0.021	6-19	0.7	0.170	0.289
							9	89	0.040	7-15	1.3	0.176	0.279
10	91	0.030	5-15	0.8	0.171	0.260
							11	92	0.048	6-19	1.3	0.177	0.252
12	92	0.030	7-18	1.0	0.167	0.242
							13	90	0.048	5-17	0.9	0.175	0.272
14	94	0.041	7-16	1.8	0.163	0.238
							15	90	0.030	7-15	1.6	0.166	0.241
16	91	0.034	8-16	1.4	0.178	0.257
							17	95	0.026	6-17	3.5	0.158	0.233
18	92	0.068	6-17	3.0	0.177	0.252
							19	91	0.024	7-15	3.8	0.169	0.268
20	90	0.031	6-16	2.8	0.179	0.292
							21	85	0.026	7-14	1.4	0.172	0.299
22	88	0.048	7-16	1.6	0.170	0.259
							23	91	0.029	6-18	1.0	0.179	0.229
24	91	0.027	6-17	0.8	0.177	0.234

Comparative example 2

Adopt the mode identical with embodiment 1, manufacturing has the Fe based amorphous alloy band of composition as shown in table 4.Their character sees Table 4.Although C content is the Fe based amorphous alloy band of 4 atom % to have heavily stressed pine and executes rate, enbrittle big and thermostability and the low shortcoming of squareness ratio.And contain the sample of a large amount of Si, the stress pine execute rate and saturation magnetic flux density low, cause in the loss of high workload magneticflux-density lower core big.

Table 4

Sample No.	Form				B80 [T]	BS [T]	B80/BS (×100％)
								Fe	Si	B	C
	25	82.0	0.1	13.9	4.0	1.600	1.661								96.3
26								82.0	4.0	10.0	4.0	1.572	1.629	96.5
	27	84.0	1.0	14.0	1.0	1.579	1.619								97.5
28								84.0	5.0	8.0	3.0	1.510	1.610	93.8

Table 4 (continuing)

Sample No.	Rs (％)	Breaking strain ε	C-segregation layer scope (nm)	C concentration peak (atom %)	W13/50 (W/kg)	W14/50 (W/kg)
							25	98	0.012	6-16	5.6	0.185	0.310
26	91	0.009	7-18	4.9	0.179	0.322
							27	93	0.030	7-17	1.5	0.204	0.385
28	82	0.018	6-15	3.4	0.250	0.420

Be limited in the predetermined scope and reduce surfaceness by weight ratio Si and C, the Fe based amorphous alloy band can have the C-segregation layer with controlled range and peak value on its depth direction, thereby minimizing embrittlement, improve magneticflux-density, squareness ratio and thermostability, and reduce core loss.C-segregation layer can produce the stress pine in nearly surface at low temperatures and execute, thereby helps stress relief to the Fe based amorphous alloy band when being wrapped on the annular core.This Fe based amorphous alloy band is especially suitable for use as the magnetic core of transformer.

Claims (7)

1, a kind of have a Fe of comprising_aSi_bB_cC_dFe based amorphous alloy band with the composition of unavoidable impurities, wherein a is 76 to 83.5 atom %, b is 12 atom % or following, c is 8 to 18 atom %, d is 0.01 to 3 atom %, has peak value to the C concentration distribution that its inner radial measures from two surfaces of Fe based amorphous alloy band in the degree of depth 2 to 20nm scopes.

2, Fe based amorphous alloy band according to claim 1, wherein a is 80 to 83 atom %, and b is 0.1 to 5 atom %, and c is 12 to 18 atom %, d is 0.01 to 3 atom %, and wherein said Fe based amorphous alloy band the saturation magnetic flux density after the annealing be 1.6T or more than.

3, Fe based amorphous alloy band according to claim 1 and 2, wherein a, b and d satisfy condition: b≤(0.5 * a-36) * d^1/3

4, according to any one described Fe based amorphous alloy band of claim 1 to 3, wherein it after annealing, the magneticflux-density in 80A/m magnetic field be 1.55T or more than.

5, according to any one described Fe based amorphous alloy band of claim 1 to 4, the annular core after the annealing of forming by described Fe based amorphous alloy band wherein, the core loss W under 1.4T magneticflux-density and 50Hz frequency_14/50Be 0.28W/kg or following.

6, according to any one described Fe based amorphous alloy band of claim 1 to 5, its breaking strain ε after the annealing be 0.02 or more than.

7, Fe based amorphous alloy band according to claim 1, wherein 50 atom % or following Fe are replaced by Co and/or Ni.

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