Imphy Alloys

Aperam

Centre National De La Recherche Scientifique

Ecole Normale Superieure De Cachan

Aperam Alloys Imphy

Alain Demier

Thierry Waeckerle

Thierry Save

Fabien Simon

Francisco Alves

Christian Caquard

Disclosed is a basic module of a magnetic core of a wound electrical transformer. The basic module includes first and second windings placed atop one another and made of first and second materials, respectively. The first material is a crystal having a saturation magnetization&#x2265;1.5 T and magnetic losses less than 20 W/kg in sine waves having a frequency of 400 Hz, for maximum induction of 1 T, and the second material is a material having an apparent saturation magnetostriction less than or equal to 5 ppm and magnetic losses less than 20 W/kg in sine waves having a frequency of 400 Hz, for maximum induction of 1 T. The cross-sections of the first winding and cross-sections of the second winding satisfy (S/(S+S); S/(S+S)) of the first material, having a high saturation magnetization, compared to the cross-section of both materials together, is 2%-50%.

Basic module for magnetic core of an electrical transformer, magnetic core comprising said basic module, method for manufacturing said magnetic core, and transformer comprising said magnetic core

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 [FeCoNi]CuSiBNbM'M&#x2033;, M&#x2032; being at least one of elements V, Cr, Al and Zn, and M&#x2033; being at least one of elements C, Ge, P, Ga, Sb, In and Be, with: a &#x2266;0.07 and b &#x2266;0.1, 0.5 &#x2266;x &#x2266;1.5 and 2 &#x2266;&#x3b1;&#x2266;5, 10&#x2266;y&#x2266;16.9 and 5&#x2266;z&#x2266;8, &#x3b2;&#x2266;2 and &#x3b3;&#x2266;2. According to the invention, the amorphous ribbon is subjected to crystallization 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&#xb0; C. and 700&#xb0; 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 a &#x3a9; 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 said method.

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

A nanocrystallised tape-wound core without a localised airgap, consisting of a nanocrystalline material with the following atomic composition: [FeNi]100-x-y-z-a-&#x3b2;-&#x3b3;CuSiBNbM'M&#x2033;, wherein a&#x2266;0.3, 0.6&#x2266;x&#x2266;1.5, 10&#x2266;y&#x2266;17, 5&#x2266;z&#x2266;14, 2&#x2266;a&#x2266;6, &#x3b2;&#x2266;7, &#x3b3;&#x2266;8, M&#x2032; is at least one of the elements V, Cr, Al and Zn, M&#x2033; is at least one of the elements C, Ge, P, Ga, Sb, In and Be, with a permeability &#x3bc; of 200 to 4000, a saturation of more than 1T, an induction range, in which the permeability does not vary by more than 5%, of more than 0.9T, a remanent induction of less than 0.02T and a cut-off frequency higher than 1 MHz, such that &#x3bc; varies by less than 1% when the core is aged for 100h at more than 100&#xb0; C., &#x3bc; varies by less than 5% when the core is coated, &#x3bc; varies by less than 15% when the temperature is in the range of &#x2212;25&#xb0; C. and +60&#xb0; C., and by less than 25% when the temperature is in the range of &#x2212;40&#xb0; C. and +120&#xb0; C., and &#x3bc; varies in a monotonic and substantially linear manner with a temperature of &#x2212;40&#xb0; C. to +120&#xb0; C.

Nanocrystalline core for a current sensor, single and double-stage energy meters and current probes containing them

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Varennes Vauzelles, France

Alain Demier