Method of producing a strip of nanocrystalline material and device for producing a wound core from said strip

Abstract

The invention relates to a method of producing a strip of nanocrystalline material which is obtained from a wound ribbon that is cast in an amorphous state, having atomic composition [Fe1-a-bCoaNib]100-x-y-2-alpha-beta-gamma Cu<x>Si<y>BzNbalphaM'betaM''gamma, M' being at least one of elements V, Cr, Al and Zn, and M being at least one of elements C, Ge, P, Ga, Sb, In and Be, with: a <= 0.07 and b = 0.1, 0.5 <= x <=1.5 and 2 <= a <= 5, 10 <= y <= 16.9 and 5 <= z <= 8, beta <= 2 and gamma <= 2. According to the invention, the amorphous ribbon is subjected to crystallisation annealing, in which the ribbon undergoes annealing in the unwound state, passing through at least two S-shaped blocks under voltage along an essentially longitudinal axial direction of the ribbon, such that the ribbon is maintained at an annealing temperature of between 530 DEG C and 700 DEG C for between 5 and 120 seconds and under axial tensile stress of between 2 and 1000 Mpa. The tensile stress applied to the amorphous ribbon, the displacement speed of the ribbon during annealing and the annealing time and temperature are all selected such that the cross-section profile of the strip is not in the form of Omega and the maximum deflection of the cross-section of the strip is less than 3% of the width of the strip and preferably less than 1% of the width. The invention also relates to the strip and the core thus obtained and to the device used to implement the method.

Description

Technical field

[0001] The present invention relates to a method for producing a strip of nanocrystalline material, a device for producing a tore enroulé from the strip, and the core and the element combining them. Background technique

[0002] In particular, the patent FR2823507 discloses the production of nanocrystalline material cores with low permeability (μ≤1000) from FeCuNbSiB type amorphous ribbons transformed by annealing.

[0003] This document specifically describes the stress annealing method of these amorphous ribbons, which significantly reduces the ultimate brittleness of nanocrystalline materials, which previously could not be processed in the form of cores after nanocrystallization. The mechanical properties that can be obtained by this stress annealing method enable the winding of the strip without the risk of breaking, and also enable the uncoiling and rewinding of the strip while still maintaining the same reel.

[0004] These improved mechanical properties are...

Examples

Embodiment 1

[0172] Example 1-Influence of grade composition

[0173] Influence of boron content

[0174] Examples V, W, and X with a boron content of 8.4% have a suitable level of brittleness, and the fracture rate is less than 5 fractures / km.

[0175] However, with such a high boron percentage, it becomes difficult to feed the crystallization under stress, especially slower than all industrially operable tests, such as C, D, E, and F, which requires reducing the feed speed To less than 4 cm / sec, and this will limit the available permeability range to permeability greater than 300. Therefore, the maximum boron content must be limited to 8%.

[0176] Moreover, Example N shows that the partial replacement of boron by 1.22% of carbon has very little damage to the product performance.

[0177] Effect of niobium content

[0178] Example J shows that if the percentage of niobium used is about 3.9%, the overall magnetic properties can be maintained, but the saturation induction B (200 Oe) will...

Embodiment 2

[0199] Example 2-Expansion

[0200] In order to study the effect of applied stress (on the tape) on the expansion of the nanocrystalline core, a series of amorphous tapes were prepared, the composition of which was consistent with casting 1 in Table 1, and the amorphous tapes were subjected to increasing tensile stress. The test conditions and the obtained results on the thickness reduction (ΔEp / Ep) and the degree of expansion are listed in Table 3:

[0201] table 3

[0202] Stress (MPa) Thickness (μm) ΔEp / Ep Expansion degree (%) 0 17.9 87.1％ 19.9 17.8 -0.6％ 86.7％ 39.8 17.7 -1.2％ 87.7％ 79.5 17.4 -2.8％ 87％ 119 17.2 -4.1％ 86.2％ 171 16.8 -6.4％ 84.6％ 200 16.6 -8.4％ 85.3％ 300 16.1 -11％ 85.7％ 500 14.9 -16.8％ 84.5％

[0203] It has been found that the method according to the present invention makes it possible to reduce the thickness of the nanocrystalline tape without significantly impairing the degree...

Technical field

[0001] The present invention relates to a method for producing a strip of nanocrystalline material, a device for producing a tore enroulé from the strip, and the core and the element combining them. Background technique

[0002] In particular, the patent FR2823507 discloses the production of nanocrystalline material cores with low permeability (μ≤1000) from FeCuNbSiB type amorphous ribbons transformed by annealing.

[0003] This document specifically describes the stress annealing method of these amorphous ribbons, which significantly reduces the ultimate brittleness of nanocrystalline materials, which previously could not be processed in the form of cores after nanocrystallization. The mechanical properties that can be obtained by this stress annealing method enable the winding of the strip without the risk of breaking, and also enable the uncoiling and rewinding of the strip while still maintaining the same reel.

[0004] These improved mechanical properties are...

Examples

Embodiment 1

[0172] Example 1-Influence of grade composition

[0173] Influence of boron content

[0174] Examples V, W, and X with a boron content of 8.4% have a suitable level of brittleness, and the fracture rate is less than 5 fractures / km.

[0175] However, with such a high boron percentage, it becomes difficult to feed the crystallization under stress, especially slower than all industrially operable tests, such as C, D, E, and F, which requires reducing the feed speed To less than 4 cm / sec, and this will limit the available permeability range to permeability greater than 300. Therefore, the maximum boron content must be limited to 8%.

[0176] Moreover, Example N shows that the partial replacement of boron by 1.22% of carbon has very little damage to the product performance.

[0177] Effect of niobium content

[0178] Example J shows that if the percentage of niobium used is about 3.9%, the overall magnetic properties can be maintained, but the saturation induction B (200 Oe) will...

Embodiment 2

[0199] Example 2-Expansion

[0200] In order to study the effect of applied stress (on the tape) on the expansion of the nanocrystalline core, a series of amorphous tapes were prepared, the composition of which was consistent with casting 1 in Table 1, and the amorphous tapes were subjected to increasing tensile stress. The test conditions and the obtained results on the thickness reduction (ΔEp / Ep) and the degree of expansion are listed in Table 3:

[0201] table 3

[0202] Stress (MPa) Thickness (μm) ΔEp / Ep Expansion degree (%) 0 17.9 87.1％ 19.9 17.8 -0.6％ 86.7％ 39.8 17.7 -1.2％ 87.7％ 79.5 17.4 -2.8％ 87％ 119 17.2 -4.1％ 86.2％ 171 16.8 -6.4％ 84.6％ 200 16.6 -8.4％ 85.3％ 300 16.1 -11％ 85.7％ 500 14.9 -16.8％ 84.5％

[0203] It has been found that the method according to the present invention makes it possible to reduce the thickness of the nanocrystalline tape without significantly impairing the degree...

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