32 results about "Piezomagnetism" patented technology

The invention provides a low-frequency mechanical antenna based on a piezoelectric-piezomagnetic composite material and a manufacturing method of the low-frequency mechanical antenna. According to the invention, a first piezomagnetic layer and a second piezomagnetic layer are tightly combined with a piezoelectric layer in a chemical bonding mode; the piezoelectric layer is covered with at least two interdigital electrodes; and when signal voltage is applied to the interdigital electrodes, the piezoelectric layer generates an inverse piezoelectric effect and converts a voltage signal into a deformation parameter of the piezoelectric layer. The two piezomagnetic layers and the piezoelectric layer are tightly combined together, the two piezomagnetic layers simultaneously generate mechanical deformation response under the mechanical deformation action of the middle piezoelectric layer, and under the action of piezomagnetic effect characteristics, the mechanical deformation response is converted into oscillation of magnetic dipoles in the two piezomagnetic layers to form magnetic field change and externally radiate a low-frequency electromagnetic field; and a magnetic field change signal is conducted to a signal receiving end, so low-frequency communication with high transmitting power and efficiency is realized, and miniaturization of low-frequency communication equipment is realized.

The invention belongs to the technical field of weak magnetic field detection, and provides an FM/FE/FM multi-iron heterojunction and a sensor. A piezomagnetic material with opposite saturation magnetostriction coefficients is selected, a positive pressure magnetic layer and a negative pressure magnetic layer are reasonably designed, the material of the positive pressure magnetic layer is selectedfrom at least one of Fe-Co-B alloy, amorphous soft magnetic strips, electrical soft iron, rare earth-iron alloy and Fe-Ga alloy, and the material of the negative pressure magnetic layer is selected from at least one of CoFe2O4 and Sm-Nd-Fe alloy. The FM/FE/FM multi-iron heterojunction can generate bending motion along with the change of an alternating magnetic field in the vertical direction, traditional telescopic motion is changed, and the resonance frequency is remarkably reduced and meanwhile the FM/FE/FM multi-iron heterojunction has high magnetic field sensitivity. The bending mode magnetoelectric coupling sensor achieves high-sensitivity measurement of an ultralow-frequency weak magnetic field, and can be used in the fields of weak magnetic field detection, military, biomedical image and inspection, geophysical, geological and mineral resource exploration, nondestructive inspection and the like.

The invention relates to a static and dynamic force-magnetic coupling material performance test instrument, and belongs to the field of precision scientific instruments. The instrument comprises a force loading module, a magnetic field loading module, a Hall probe, a measuring coil, a strain gauge and the like. The force loading module applies the static and dynamic loads on a sample by utilizinga servo motor and a piezoelectric stack, the magnetic field loading module provides a static and dynamic magnetic field parallel or perpendicular to a load direction through a variable air gap electromagnet and a Helmholtz coil, and the important performance parameters and curves, including an elastic coefficient, a piezomagnetic coefficient, a hysteresis loop, a magnetostriction curve, a stress-strain curve and the like, of the material under different loads and bias magnetic fields can be obtained through a force-magnetic coupling test. The instrument has the advantages that the important physical properties of the material in a force-magnetic coupling environment can be tested, and the instrument is of great significance to the research of the constitutive relation of the magnetostrictive material.

The invention provides a low-frequency magneto-electric composite mechanical antenna with a novel structure and a manufacturing method thereof, and belongs to the technical field of low-frequency communication. A structural unit of the low-frequency magneto-electric composite mechanical antenna comprises a core rod with a piezoelectric function, a core shell module with a piezomagnetic function and a hoop buckle for fastening and fitting the core rod and a core shell. The core shell is composed of a plurality of arc shell bodies, the inner diameters of the arc shell bodies are equal to the outer diameter of the core rod, the number of the arc shell bodies is at least two, and a telescopic gap is reserved between every two adjacent arc shell bodies. Compared with a traditional magneto-electric composite mechanical antenna, the low-frequency magneto-electric composite mechanical antenna of the novel structure has the advantages that the possible negative effect of strain conduction between different phases caused by chemical interface bonding is weakened, and strain conduction is timely, efficient and uniform.

The invention discloses an improved analytical model of motor stator core vibration induced by magnetostriction. According to the characteristics of a structure and magnetic field distribution of a radial flux motor, a stator core is divided into two subdomains: a yoke and a tooth; the vibration of the yoke is the vibration of a torus and the vibration of the tooth is the vibration of a rectangular block; based on a piezomagnetic equation and the Newton's law, vibration partial differential equations of the yoke and the tooth of the stator core along the radial and axial directions are established; and a vibration differential equation is solved by adopting a method of separation of variables, and undetermined coefficients are solved according to a boundary condition. The improved analytical model of the motor stator core vibration induced by the magnetostriction provided by the invention is accurate in calculation result and clear in physical conception, can be applied to calculating the vibration displacement, velocity and acceleration of the motor stator core induced by the magnetostriction, the stress and strain distribution characteristics, and is an effective method for motor vibration analysis.

The invention discloses a method for predicting fatigue life by utilizing a weak magnetic signal of a ferromagnetic material. The key point of the method is that weak magnetic signals in the fatigue crack propagation process are detected; a quantitative relation between a weak magnetic signal characteristic parameter and a fatigue crack propagation parameter is established through data analysis byutilizing a piezomagnetic signal monitored by a fixed magnetic probe and a magnetic field distribution signal detected by a movable magnetic probe, and finally a quantitative relation between the weak magnetic signal characteristic parameter and a fatigue life Nf is established. According to the method, nondestructive evaluation of the crack propagation process of the ferromagnetic material and quantitative prediction of the fatigue life can be realized.

The invention discloses a spherical three-dimensional force measurement piezomagnetic sensor and a three-dimensional force measurement method thereof. The spherical three-dimensional force measurement piezomagnetic sensor comprises a force measurement mechanism, a signal excitation circuit and a signal conditioning circuit, the force measurement mechanism comprises a spherical shell, a force transmission element connected in the three-dimensional orthogonal direction of the inner surface of the spherical shell, and a piezomagnetic element connected with the force transmission element. The piezomagnetic element receives an external force applied to the spherical shell through the force transmission element; after the piezomagnetic element receives the external force, the signal excitation circuit transmits an excitation signal to the piezomagnetic element, so that the piezomagnetic element converts the external force into a non-zero induction voltage and transmits the induction voltage to the signal conditioning circuit; and the signal conditioning circuit performs signal compensation, output decoupling and component force synthesis on the induced voltage to obtain an external force value and a component force value in each direction. Loading force in all directions can be accurately detected, the bias degree of a magnetic field is increased on the basis of equal stress deformation, and therefore the complex working conditions in practical application are met.

The invention relates to the field of communication, and discloses a magnetoresistive integrated stress sensor and a preparation method and application thereof. Themagnetoresistive integrated stress sensor comprises a substrate; a permanent magnet thin film layer which is arranged on one side of the substrate; a piezomagnetic thin film layer which is arranged on the substrate on the other side opposite to the permanent magnet thin film layer and is used for receiving external stress and outputting voltage; and a metal electrode which is arranged on the piezomagnetic thin film layer. According to the invention, the magnetic moment of the material can be changed through the change of the magnetic conductivity of the bridge on the piezomagnetic film layer, and the change of the magnetic moment of the material can cause the change of the magnetoresistance of the material, so that the measurement of the direction and the magnitude of the pressure is realized.

The invention discloses an antenna and an electronic device. The antenna comprises a piezoelectric structure and a piezomagnetic structure, and the piezoelectric structure and the piezomagnetic structure are configured to enable the piezomagnetic structure to generate mechanical deformation and generate electromagnetic waves when the piezoelectric structure generates mechanical deformation under the action of an electric field. The antenna has the advantages of simple structure, high efficiency, portability and the like.

The invention provides a continuous measurement method and system of plane stress of earth crust rock mass. The method comprises steps of firstly, using a piezomagnetic sleeve core to determine the reference plane main stress of earth crust rock mass in a preset depth place of a target borehole and determine a second linear relation between second piezomagnetic sensing elements on a piezomagneticmonitoring probe; then, based on stress states of a piezomagnetic relieving probe in the preset depth place of the target borehole, adjusting stress states of the second piezomagnetic sensing elementson the piezomagnetic relieving probe in the corresponding positions; and finally, measuring the voltage drop of each second piezomagnetic sensing element on the piezomagnetic monitoring probe at anymoment after the adjustment and according to the reference plane main stress, the second linear relation and the current voltage drops, determining the current plane main stress. In this way, the absolute earth crust rock mass plane main stress at any moment in the preset depth place of the target borehole can be acquired in real time, and real-time monitoring of plane main stress in the preset depth of a certain target borehole in the earth crust rock mass is achieved.

The invention discloses a magnetoelectric coupling-based bulk acoustic wave magnetic field sensor and an optimization method thereof. The magnetoelectric coupling-based bulk acoustic wave magnetic field sensor structurally comprises a magnetic composite film and a bulk acoustic wave resonator, the magnetic composite thin film comprises a FeGaB magnetostrictive thin film and an Al2O3 thin film inserted into the FeGaB magnetostrictive thin film; the bulk acoustic wave resonator comprises a Mo electrode film, an AIN piezoelectric film and a silicon substrate which are arranged in sequence. According to the bulk acoustic wave magnetic field sensor, the composite magnetic film is adopted, eddy current loss is restrained, and the soft magnetic characteristic is enhanced; meanwhile, a piezomagnetic phase/piezoelectric phase double-layer structure design is adopted, so that the magnetoelectric (ME) coupling efficiency is improved; the resonance is utilized to enhance the ME coupling effect, and the thickness of the piezoelectric phase/piezomagnetic phase and the electrode layer is designed, so that the sensor works at the ferromagnetic resonance frequency of the composite film, and the energy conversion efficiency is further improved. Therefore, the performance optimization method of the bulk acoustic wave magnetoelectric coupling magnetic field sensor is obtained.

The invention discloses a main and auxiliary magnet double-acting piezomagnetic coupling vibration energy harvester, which comprises a bracket and a simply supported beam, wherein the simply supportedbeam is fixedly connected to the left side of an inner cavity of the bracket; a piezoelectric plate is adhered to the top part of the simply supported beam; a first magnetic block is adhered to the top part of the piezoelectric plate, a second magnetic block is adhered to the middle of the top part of the inner cavity of the bracket; a first coil is adhered to the right side of the top part of the inner cavity of the bracket; a third magnetic block is adhered to the right side of the top part of the simply supported beam; and a fourth magnetic block is adhered to the middle of the bottom partof the simply supported beam. According to the main and auxiliary magnet double-acting piezomagnetic coupling vibration energy harvester, the bracket, the piezoelectric plate, the first magnetic block, the second magnetic block, the third magnetic block, the first coil, the fourth magnetic block, a fifth magnetic block, the simply supported beam, a sixth magnetic block and a second coil cooperatewith each other, the stress of the piezoelectric plate and the simply supported beam is adjusted by using a nonlinear magnetic force, so that the stress borne by the simply supported beam and the piezoelectric plate is more uniform, the utilization rate of the piezoelectric plate is improved, the energy harvesting effect of the device is improved, and the service life of the device is prolonged.

The invention provides a magneto coupling resonance type micro-nano weighing device and a preparation method thereof, and belongs to the technical field of micro-nano electronic functional devices.The device comprises a single crystal substrate, a short-circuit coplanar waveguide and a resonator, the short-circuit coplanar waveguide and the resonator are located on the single crystal substrate, and the resonator is located between a center band and a grounding band of the short-circuit coplanar waveguide; the resonator comprises a piezomagnetic film on the upper layer and a magnetic film on the lower layer, and the magnetic damping coefficient of the magnetic film is lower than 10 <-3 >. Preferably, the magnetic thin film is a yttrium iron garnet thin film, and the single crystal substrate is a gadolinium gallium garnet single crystal substrate with a [111] crystal orientation. According to the invention, an object with the mass at the nanogram level is accurately weighed based on a full-electromagnetic method, and compared with a traditional cantilever beam mechanical vibration resonant frequency test method, the method has the advantages that the requirement on the vacuum degree of a measurement environment is not strict, the cost is reduced, and the method has relatively high test sensitivity in a microwave frequency band; and the magnetic film with low ferromagnetic resonance line width is adopted, so that the overall absorption bandwidth of the resonator is narrowed, and absorption peak signals can be extracted.

The invention relates to the field of acoustic wave detection, and particularly provides an acoustic wave sensor based on a Kerr effect. A piezomagnetic material layer is arranged on a substrate, thesurface of the piezomagnetic material layer is a plane, and cavities are periodically arranged in the piezomagnetic material layer. When the acoustic wave sensor is applied, the acoustic wave sensor based on the Kerr effect is placed in a to-be-detected environment or is in contact with a to-be-detected object; under the action of sound waves in a to-be-detected environment or a to-be-detected object and the acousti wave sensor based on the Kerr effect, stress in the piezomagnetic material layer is changed, linearly polarized light obliquely irradiates the piezomagnetic material layer, an external magnetic field is applied in the direction perpendicular to the incident plane, and sound wave detection is achieved by detecting the intensity of reflected light. The magnetic conductivity of the piezomagnetic material layer seriously depends on the internal stress borne by the piezomagnetic material layer, so that high-sensitivity detection of sound waves can be realized, and the piezomagnetic material layer has a good application prospect in the field of sound wave detection.

The invention discloses a pin-type piezomagnetic sensor and a control system comprising the same. The pin-type piezomagnetic sensor comprises a sensor body, wherein the sensor body mainly comprises a piezomagnetic element, the piezomagnetic element comprises a central bearing cylinder, a support, a cross excitation magnetic core and a winding thereof, an induction magnetic core and a winding thereof, and an intermediate magnetic circuit; the cross-shaped excitation magnetic core is fixed at the central position of the central bearing cylinder; an X-direction excitation winding NX and a Y-direction excitation winding NY are arranged on the cross-shaped excitation magnetic core; and the two ends of the central force bearing cylinder are each provided with a support, an induction magnetic core is installed on each support, and an induction winding is arranged on each induction magnetic core. Compared with a traditional piezomagnetic force sensor, the pin-type piezomagnetic sensor has the advantages that: the defect that the measuring range is large but the precision is not accurate can be overcome, and the high precision is guaranteed when the large measuring range is achieved; and the device capable of automatically adjusting the measuring range is arranged, the measuring range can be adjusted according to the requirement of the using environment, more measuring environments can be adapted, and energy consumption is lower.

A magnetic sensor includes a piezomagnetic component which includes a first piezomagnetic element and a second piezomagnetic element that are arranged opposite to each other, a magnetostrictive component which includes a first magnetostrictive element and a second magnetostrictive element arranged opposite to each other on the same side of the first piezomagnetic element and the second piezomagnetic element, respectively, and a piezoelectric component which includes a first piezoelectric element deposited underneath the first piezomagnetic element, a second piezoelectric element deposited underneath the second piezomagnetic element, a third piezoelectric element deposited underneath the first magnetostrictive element, and a fourth piezoelectric element deposited underneath the second magnetostrictive element. The first piezoelectric element and the second piezoelectric element are electrically connected to a power supply circuit, and produce first deformation, which is applied to the first piezomagnetic element and the second piezomagnetic element to produce an alternating magnetic field.

The invention provides a surface plasmon enhanced acoustic wave sensor based on a Kerr effect, which comprises a substrate, a piezomagnetic material layer, grooves and noble metal particles, the piezomagnetic material layer is arranged on the substrate, the grooves are periodically arranged on the surface of the piezomagnetic material layer, and the noble metal particles are arranged in the grooves. During application, linearly polarized light obliquely irradiates the piezomagnetic material layer, an external magnetic field is applied in the direction perpendicular to the incident plane, and sound wave detection is achieved by detecting the intensity of reflected light. The method has the advantages of being high in sensitivity and convenient to use.

A perforated brick surface identification treatment system comprises a conveying assembly, a heating assembly, an imprinting assembly, a detection assembly, and a controller, wherein the detection assembly comprises a detection frame, a force transmission needle, an elastic body and a piezomagnetic element; the detection frame is fixedly arranged on the conveying assembly, the force transmission needle is slidably arranged at the bottom of the detection assembly, the elastic body is fixedly connected to the top of the force transmission needle, and the piezomagnetic element is fixedly arranged at the top of the elastic body; the controller is arranged outside the detection assembly, and the conveying assembly, the heating assembly, the imprinting assembly and the detection assembly are all electrically connected with the controller. The conveying assembly is used for conducting imprinting on brick bodies through the heating assembly and the imprinting assembly, then the brick bodies are detected through the detection assembly, and the controller controls the conveying assembly to move reversely to conduct imprinting again on the incompletely-imprinted brick bodies till the brick bodies are qualified. The effect of complete imprinting is achieved, meanwhile, incompletely imprinted products can be further processed until the products are qualified, the quality of the products is ensured, and meanwhile, waste of the products is avoided.

The invention provides a wireless charging coil enameled wire with a magnetic nano ferrite material inner layer, and a preparation method of the wireless charging coil enameled wire. The wireless charging coil enameled wire sequentially comprises an insulating macromolecule polymer outer layer, a FeaCobBc doped silver-copper alloy conductive middle layer and a piezomagnetic nanoparticle doped polyvinylpyrrolidone nanofiber ferromagnetic ceramic material inner layer from outside to inside, wherein the inorganic insulating outer layer and the conductive inner layer are distributed on the outer side arc of the magnetic nano ferrite material inner layer at intervals, the angle of the interval distribution is 15-20 degrees, the interval distribution pores are filled with an insulating material,and the weight ratio of the outer layer to the middle layer to the inner layer is (1-5):(8-10):(3-5). According to the magnetic nano ferrite solid core with the piezoelectric property, the conductivemiddle layer and the insulating outer layer, the flexibility and the bending property of the enameled wire can be improved, the electricity generation property of the enameled wire after piezoelectricity is further improved, and the enameled wire of the wireless charging coil has high magnetostriction, high magnetoelectric conversion efficiency and high safety performance.