771 results about "Saturation (magnetic)" patented technology

The invention relates to a magnetic clay material and a preparation method thereof. The magnetic clay material is a superparamagnetc material formed by loading nano-iron oxide particles (gamma-Fe2O3) on the clay surface. In the preparation process, the surfactant is used as a template agent, the immobilization process of hydrated hydraferro on the surface of montmorillonite clay is regulated, and fumigating with acetic acid and thermal treatment are performed to obtain the superparamagnetc clay material. The micelle formed by the surfactant is synergic with the immobilization of the hydrated hydraferro on the clay surface, the load capacity is increased, and thus the magnetic saturation strength of the magnetic clay is enhanced. The magnetic clay material provided by the invention not only has the characteristics of large adsorption capacity and strong adsorption ability, but also can realize the aim of enhanced separation in the using process of material by using external magnetic field, and solve the problem of secondary pollution as the clay material is difficult to separate and recycle.

The invention provides a soft-magnetic high-entropy block amorphous alloy FeCoNiMB. M represents at least one of P, C and Si elements, and typical compositions include Fe25Co25Ni25Si7.5B17.5, Fe25Co25Ni25Si10B15, Fe25Co25Ni25P5C4Si6B10, Fe25Co25Ni25P12C8B5 and Fe25Co25Ni25P10C10B5. The saturation magnetization of the alloy is 0.80-0.87T, coercivity is 1.1-3.4A/m, and effective magnetic conductivity under 1kHz is 12500-19800. The invention further provides a preparation method of the soft-magnetic high-entropy block amorphous alloy. The preparation method includes preparing a master alloy ingot through arc melting or induction melting, and preparing an amorphous band and an amorphous bar by single-roll melt-spinning and copper-mold casting respectively. The technical blank in preparation of the soft-magnetic high-entropy block amorphous alloy is filled up, and the provided alloy has an application prospect of serving as a soft-magnetic functional device.

The invention belongs to the field of soft-magnetic ferrite materials. The objective of the invention is to provide a soft-magnetic nickel-copper-zinc ferrite material and a preparation method thereof. The material provided by the invention comprises major components and minor components. The major components comprise the following raw materials in mole percentage: 47.0-49.0mol% of Fe2O3, 17.5-18.5mol% of NiO, 26.0-29mol% of ZnO and 6.0-7.0mol% of CuO. The minor components comprise, based on the total weight of the major components, 0.1-0.40% of MnO, 0.1-0.5% of Bi2O3 and 0.3-0.5% of Co2O3. Under a high frequency of 13.56 MHz, the material provided by the invention has the characteristics of high magnetic conductivity ([mu]' is approximately equal to 130), low complex magnetic permeability [mu]''(namely low loss), high resistivity, high Curie temperature, high saturation magnetic induction density Bs, and the like.

Apparatus for detecting the presence of magnetic elongated particles in a substrate, the base material of the substrate having magnetic properties substantially differing from the corresponding magnetic properties of the elongated particles. The elongated particles have such a long and thin form that their demagnetization factor N is smaller than {fraction (1/250)}, they have a diameter smaller than 30 micrometer, and they a magnetic saturation field greater than 100 A/m. Apparatus includes an emitter which emits an electromagnetic source signal of one or more particular base frequencies to the substrate (e.g., so that any magnetic elongated particles present go into a non-linear part of a B-H curve for at least part of cycle of the source signal). Apparatus also includes a detector that detects an electromagnetic detection signal emanating from the substrate for examining the detection signal for the presence of particular higher harmonics of the base frequencies or of any linear combination of the base frequencies or of the harmonics, particular higher harmonics being indicative of the presence of the magnetic elongated particles.

The invention relates to a manganese zinc ferrite material with wide temperature and low power. The material comprises main components and auxiliary components; the main components comprise the following components in percentages by mol: 52.7-53.5mol% of Fe2O3, 8.6-9.6mol% of ZnO, and the balance being MnO; based on the total weight of the main components, the auxiliary components comprise the following components in percentages by weight: 0.03-0.04% of CaCO3, 0.02-0.03% of Nb2O5, 0.4-0.5% of Co2O3, 0.05-0.15% of SnO2, and 0.0074-0.022% of NaO2 (NaO2 is added in the form of sodium bicarbonate). Insulation treatment for controlling atmosphere is carried out at 1200 DEG C in the sintering cooling stage. The ferrite material has low power consumption in the temperature range of 25-140 DEG C, and at the same time, the material has high saturation magnetic flux density and high magnetic permeability.

The invention relates to an iron-based alloy magnetic powder core adopting a core-shell heterostructure and a preparation method thereof. The technical scheme is as follows: 80-95wt% of iron-based alloy powder and 5-20wt% of inorganic oxide powder are evenly mixed and subjected to ball milling for 1-5 h under the shielding of an inert gas, the ball-milled iron-based alloy composite powder is contained in a graphite die, then the graphite die is placed in a plasma activation sintering furnace to be heated to 900-1250 DEG C, the pressure is exerted on the graphite die to 20-50 MPa, and the temperature is kept for 5-30 min under the shielding of the inert gas; the temperature is reduced to 400-500 DEG C at the temperature reduction rate of 30-50 DEG C/min, and the graphite die is cooled along with the furnace; the pressure exerted on the graphite die is unchanged when the temperature is kept and reduced to 400-500 DEG C, and the pressure is reduced to 0 at a constant speed during cooling; the graphite die is taken out of the furnace, and demolding is performed to obtain the iron-based alloy magnetic powder core adopting the core-shell heterostructure. The preparation method is simple in process, high in preparation efficiency and low in preparation cost; the iron-based alloy magnetic powder core is high in saturation flux density, high in density, good in insulating property, low in eddy-current loss and good in thermal stability.

The invention discloses a nanocrystal magnetically soft alloy with high processing property and high saturation magnetic induction strength, and a preparation method therefor, and belongs to the technical field of a new material. The chemical formula of the nanocrystal magnetically soft alloy is FeBSi<c>Cu<d>C<e>M<f>Z<g>, wherein M is at least one kind of elements Co or Ni; Z is at least one kind of elements Al, Cr, Mn, Ti, Nb, Ta or Mo; a, b, c, d, e, f and g are atomic percentage contents of corresponding elements, and satisfy the formula as follows: a+f is greater than or equal to 80 and less than or equal to 84; b is greater than or equal to 10 and less than or equal to 15; c is greater than or equal to 0 and less than or equal to 6; d is greater than or equal to 1.6 and less than or equal to 2.2; e is greater than or equal to 0 and less than or equal to 2; f is greater than or equal to 0 and less than or equal to 5; and g is greater than or equal to 0 and less than or equal to 2. The alloy is formed by uniformly dispersing an <alpha>-Fe phase, which is obtained by heat treatment of amorphous stripes and has the crystal grain sizes of less than 50nm, into residual amorphous phase tissues, wherein the saturation magnetic induction strength is greater than 1.7T, and the coercivity is less than 15A/m. The alloy has no volatile phosphorus element; in addition, the heat treatment process is simple, and high temperature-rise rate is not required; the heat treatment temperature range and the thermal insulation time range are wide; industrial production can be realized easily; and the nanocrystal magnetically soft alloy and the preparation method therefor are convenient to popularize and use.