15 results about "Curie" patented technology

This invention discloses a high Curie temperature, high frequency, and high impedance manganese-zinc ferrite material and its preparation method, belonging to the technical field of soft magnetic ferrite materials. The manganese-zinc ferrite material consists of a main component and secondary components. The main component, calculated as oxides, comprises Fe2O3: 48.5–49.9 mol%, ZnO: 18.5–21.5 mol%, NiO: 0.5–2.0 mol%, with the remainder being MnO. The secondary components, by weight of the main component, include at least four of the following: Co2O3: 0.05–0.30 wt%, SiO2: 0.005–0.01 wt%, CaCO3: 0.02–0.05 wt%, ZrO2: 0.01–0.02 wt%, Bi2O3: 0.01–0.03 wt%, and V2O5: 0.01–0.05 wt%, mixed in any proportion. The resulting manganese-zinc ferrite material exhibits excellent properties such as high impedance.

The application provides high-curie-temperature low-resistance lead-free thermosensitive ceramic and a preparation method thereof, and belongs to the technical field of electronic ceramic elements. 1‑x‑y La x (Bi 0.5 Na 0.5 ) y )(Ti 0.9996 Mn 0.0004 )O3; wherein the value range of x is 0.001<=x<=0.004, and the value range of y is 0.001<=y<=0.0075. The preparation method comprises the following steps: mixing (Bi 0.5 Na 0.5 )TiO3 powder synthesized by two-stage heating hydrothermal method, (Ba 1‑x La x )TiO3 powder synthesized by solid-phase reaction method, Mn(NO3)2 aqueous solution and sintering auxiliary agent AST powder, then performing granulation, molding, glue removal and sintering. The barium titanate-based thermosensitive ceramic prepared by the method has extremely low room temperature resistivity and relatively high curie temperature.

The application relates to the technical field of magnetocaloric materials, and discloses a low-curie-temperature iron-based magnetocaloric material, a preparation method, a deicing agent and a coating. The magnetocaloric material takes iron as the main body, introduces rare earth elements, transition group elements and metalloid elements to form a synergistic component system, and has the characteristics of adjustable curie temperature and high saturation magnetic induction intensity. The preparation method comprises the following steps: alloy smelting and high-temperature homogenization heat treatment, block pretreatment, segmented parameter control hydrogen crushing, and gradient temperature rising high-vacuum dehydrogenation. Through the hydrogenation process combining low-temperature permeation, high-pressure crushing and heat preservation and refinement, the uniform and controllable crushing of the alloy is realized, and the residual hydrogen content is effectively reduced in the multi-stage dehydrogenation process. The application can significantly improve the problems of serious oxidation, uneven particle size and magnetic performance attenuation existing in the traditional mechanical crushing or conventional hydrogen crushing process. The obtained magnetocaloric material shows high saturation magnetic induction intensity and stable magnetocaloric performance in the low curie temperature interval.

The invention relates to a passive temperature sensor-antenna (10) comprising: - a plurality of layers of ferroelectric materials (12.1, 12.3, 12.4) arranged side by side on a support (11) made of an electrically conductive material, - said layers of ferroelectric materials (12.1, 12.3, 12.4) being made of different ferroelectric materials having different Curie temperatures, each associated with a peak in dielectric constant, so that said sensor-antenna (10) exhibits several resonance frequencies corresponding to the Curie temperatures to cover a temperature measurement range, and - a plurality of electrically conductive layers (13.1, 13.3, 13.4) each deposited on a corresponding layer of ferroelectric material (12.1, 12.3, 12.4). Figure 4

This invention relates to a method for preparing tritelluride microsheets, comprising the following steps: Step 1, M... 2+ and / or M 3+ A precursor solution is obtained by dissolving the precursor solution in an organic solvent. Tri-n-octylphosphine and Te are then mixed to obtain a mixed solution; M is at least one of Cr, V, and Gd. Step two: The precursor solution and the mixed solution are stirred and reacted to obtain MTe3 seed crystals. Step two: The MTe3 seed crystals are added to the precursor solution and then to the mixed solution for further reaction to obtain tritelluride microsheets. This method allows for balanced and controllable crystal growth, significantly improving the lateral dimensions and crystal integrity of the CrTe3 microsheets. The CrTe3 microsheets prepared using this method exhibit excellent structural integrity, with lateral dimensions ranging from 2 to 200 μm, and demonstrate intrinsic ferromagnetic behavior at high Curie temperatures, providing a new technical approach for the large-scale fabrication of high-performance two-dimensional magnetic materials and spintronic devices.

The invention discloses an integrated energy conversion device based on cold and heat energy exchange and negative correlation characteristic coupling of temperature and magnetic force or magnetic conductivity characteristics, and relates to the technical field of energy conversion. The device comprises a temperature difference control magnetic force system, a cold and heat energy supply module, a cold and heat conduction path, an integrated control and power supply module and the like, and is directly thermally coupled through negative correlation characteristics of a cold and heat energy manufacturing system-temperature and magnetic force or magnetic conductivity characteristics, or a cold and heat energy manufacturing system-Curie effect dual-thermal coupling architecture. By utilizing the characteristic that the temperature is negatively correlated with the magnetic force or magnetic conductivity of a ferromagnetic substance and combining a cold and heat energy manufacturing system, the energy conversion is realized by supplying cold and heat energy of a magnetothermal effect or a refrigeration cycle.

According to the low-cost high-magnetic-conductivity high-magnetic-shielding magnetically soft alloy and the preparation method thereof, Fe-Si-Al is adopted as a basic system, microalloying elements such as B and Nb are creatively introduced, specific critical cold rolling and magnetic field heat treatment processes are adopted, and the obtained magnetically soft alloy has high magnetic conductivity and high magnetic shielding effectiveness. Wherein the resistivity of the alloy is effectively improved and the magnetocrystalline anisotropy is optimized through the synergistic effect of Si and Al; the grain boundary segregation effect of the B element purifies the grain boundary, and the moving resistance of the magnetic domain wall is remarkably reduced; and the dispersed precipitated phase formed by the Nb element effectively refines the initial crystal grains and lays a foundation for subsequent formation of uniform and thick recrystallized crystal grains. Particularly, a strong Gaussian texture is induced through accurately controlled critical cold rolling deformation, and magnetic domains are directionally arranged in an easy magnetization direction in combination with magnetic field heat treatment applied near a Curie point, so that the coercive force is fundamentally reduced, and the initial magnetic conductivity is improved.

The invention belongs to the technical field of electronic ceramics, and particularly discloses a low-Curie-temperature medium-entropy lead magnesium tungstate-based ceramic and a preparation method and application thereof, the chemical general formula of the low-Curie-temperature medium-entropy lead magnesium tungstate-based ceramic is Pb (Mg < 1 / 4 > W < 1 / 4 > B '< 1 / 4 > B' < 1 / 4 >) O3, B '= Yb < 3 + > or Lu < 3 + >; b ''= Nb < 5 + > or Ta < 5 + >. According to the low-Curie-temperature medium-entropy lead magnesium tungstate-based ceramic and the preparation method and application thereof, the Curie temperature TC of the lead magnesium tungstate ceramic can be effectively reduced through the method, the dielectric constant is increased, low dielectric loss is kept, and the obtained ceramic has a pure perovskite structure and good compactness; the phase change temperature of the lead magnesium tungstate-based antiferroelectric ceramic ranges from-11 DEG C to-24 DEG C, the maximum relative dielectric constant ranges from 800 to 1100, the maximum dielectric loss tan delta ranges from 0.05 to 0.065, and the problems that an existing lead magnesium tungstate-based antiferroelectric ceramic is high in phase change temperature and low in dielectric constant can be solved.

A manufacturing method for a permanent magnet includes a magnetization step of magnetizing a to-be-magnetized object by a magnetizer including a field magnet unit having a plurality of permanent magnets for magnetization configured to generate a magnetic field on the to-be-magnetized object arranged at equal intervals and a heating unit having a heating surface opposing the to-be-magnetized object in an axial direction of the to-be-magnetized object and configured to heat the to-be-magnetized object. In the magnetization step, the to-be-magnetized object is disposed on the field magnet unit, the to-be-magnetized object is heated by the heating unit to a temperature equal to or higher than a Curie point of the to-be-magnetized object and lower than the Curie point of the permanent magnets for magnetization, and then the temperature is lowered to a temperature lower than the Curie point of the to-be-magnetized object, and a magnetization magnetic field is applied to the to-be-magnetized object by the permanent magnets for magnetization.

This invention discloses a high Curie point, low voltage, and low resistance ceramic PTC element, its preparation method, and its application, relating to the field of ceramic PTC technology. The invention uses a solid solution system composed of barium titanate and lead titanate as the main components, controlling the molar ratio of barium to lead within the range of 0.63-0.70:0.30-0.37. This allows the Curie point of the material to be stably distributed in the high-temperature range of 240℃ to 280℃. By optimizing the doping system, a high temperature coefficient of resistance and a high step-up resistance ratio are maintained while achieving low room temperature resistance. The invention employs separate pre-firing methods, allowing barium titanate and lead titanate to be synthesized and semiconducted separately under their respective optimal temperature conditions, ensuring precise control of the Curie point. This avoids localized inhomogeneities caused by difficulties in solid solution during final mixing, achieving controllable and repeatable product performance, suitable for large-scale production. This invention successfully solves the problems of high Curie point, low voltage, and low resistance PTC element preparation difficulty and unstable performance in existing technologies, and has good prospects for industrial application.

An active magnetic regenerator according to one embodiment comprises: a housing; a plurality of magnets disposed outside the housing; a Peltier element disposed inside the housing; a plurality of magnetocaloric materials disposed in a line on both sides of the Peltier element inside the housing and having different Curie temperatures; a plurality of connectors connecting each of the plurality of magnetocaloric materials to the Peltier element; a power supply unit for supplying power to the Peltier element; and a controller for controlling the power supply unit.

The embodiment of the invention relates to the technical field of emergency protection devices of reactors, in particular to an armature assembly, a passive shutdown device and a reactor. The armature assembly comprises an inner armature, an outer armature, an armature sheath and Curie point soft magnetic alloy. Along the radial direction of the inner armature, the armature sheath is fixedly arranged between the outer armature and the inner armature. The Curie point soft magnetic alloy is fixedly connected with the inner armature, and the magnetic force borne by the Curie point soft magnetic alloy at the position where the Curie point soft magnetic alloy is located is the maximum. By means of the armature assembly, when the temperature in a reactor is lower than the Curie temperature of a Curie-point magnetically soft alloy, it can be ensured that the armature assembly is stably attracted by electromagnetic force generated by the electromagnet assembly, accidental falling of the armature assembly is avoided, and when the temperature in the reactor rises to the Curie temperature, the armature assembly and the electromagnet assembly can be rapidly demagnetized, and the electromagnetic effect is improved. Therefore, the armature assembly drives the control rod to fall into the reactor core, rapid and safe reactor shutdown is realized, and the reliability and sensitivity of the passive reactor shutdown device are improved.

The invention relates to a powder sleeve assembly and a process for preparing a core filling micropore ultra-thin strip in a rolling mode through the powder sleeve assembly, and belongs to the technical field of metal machining and material preparation.The powder sleeve assembly comprises a hollow sleeve and a middle interlayer arranged in the hollow sleeve, and an alloy layer for filling the uppermost layer of the hollow sleeve is arranged on the middle interlayer; a middle interlayer is arranged in the hollow sleeve, a ferromagnet layer filling the lowermost layer of the hollow sleeve is arranged below the middle interlayer, the alloy layer is made of nickel-based alloy powder, the ferromagnet layer is made of ferromagnet powder including 1 / 4 nickel-based alloy powder and 3 / 4 ferromagnet powder, and by means of the large-deformation rolling technology and the heat treatment technology, the induction function of all the layers can be not affected, and meanwhile the induction function of all the layers is not affected. Metallurgical bonding is achieved by internally filling the sensing material, and meanwhile gradient sensing materials with different Curie temperatures are successfully obtained.

The application provides a wideband high-impedance high-Curie-temperature manganese-zinc ferrite material which is prepared from main components, auxiliary components and additives; the main components are composed of Fe2O3 51.8-52.5 mol%, ZnO 19.4-20.2 mol% and the rest is Mn3O4 in terms of mole percentage; the auxiliary components include CaCO3 400-600 ppm, SiO2 100-200 ppm, V2O5 500-700 ppm, SnO2 300-400 ppm and WO3 100-200 ppm in terms of the total mass of the main components; and the additives include LiCl 100-200 ppm in terms of the total mass of the main components. The formula of the manganese-zinc ferrite and the preparation process thereof are reasonably limited, and finally the manganese-zinc ferrite material with excellent comprehensive performance is prepared.

The invention discloses a method for enhancing the piezoelectric property of a PZT film through rapid annealing, which comprises the following steps: 1) in a vacuum environment of a sputtering chamber of magnetron sputtering equipment, depositing a PZT film with a crystal structure on a substrate which is heated to a set temperature by a PZT target material; (2) the PZT film is taken out of a sputtering cavity of the magnetron sputtering equipment and then put into a hearth of a rapid annealing furnace, the hearth of the rapid annealing furnace is vacuumized, the PZT film is annealed in a vacuum environment and then cooled along with the furnace, the annealing temperature is larger than the Curie point of the PZT film, and therefore phase structure reconstruction and ferroelectric domain reorientation of the PZT film are achieved; therefore, the transverse piezoelectric coefficient of the PZT film is improved. According to the method, the PZT film deposited on the substrate is crystallized to form a crystal structure, the PZT film is annealed and heated to the Curie point or above, phase structure reconstruction and ferroelectric domain redistribution of the PZT film are achieved, and the transverse piezoelectric coefficient of the PZT film is greatly improved.