131 results about "Critical current" patented technology

The invention discloses a superconducting wire performance testing device which is characterized by comprising a sample rod, a conductor critical current testing framework, a conductor mechanical performance testing framework and a Dewar. During performance testing, the sample rod and the conductor critical current testing framework are detachably connected and located in the Dewar; or the sample rod and the conductor mechanical property testing framework are detachably connected and located in the Dewar. The testing device provided by the invention can be used for both critical current testing and mechanical performance testing.

The invention relates to the technical field of superconducting material processing, in particular to a preparation method of an Nb3Sn superconducting wire. The method mainly comprises the steps that Nb-Zr alloy is loaded into the exterior and / or the center of a Sn-Cu single-core rod, oxide powder is filled between the Nb-Zr alloy and the Sn-Cu single-core rod, then the Sn-Cu single-core rod and the Nb-Zr alloy are loaded into a copper substrate, and Nb3Sn subcomponents are obtained after multi-pass stretching, forming and fixed-length cutting; and uniformly arranging the Nb3Sn sub-components in the copper pipe along the circumferential direction to form a bundle, and after multi-pass stretching, carrying out heat treatment and cutting to obtain the Nb3Sn superconducting wire. By introducing the artificial point pinning array in density gradient distribution, the critical current density of the Nb3Sn superconducting wire in a high magnetic field of 8T-16T is enhanced, the problems that an existing uniform artificial point pinning center scheme generates a matching effect and limits the actual application of the superconducting wire are solved, and the decline degree of the critical current density of the Nb3Sn superconducting wire in the high field is relieved.

The invention relates to a superconducting electrical switch. The switch comprises two parallel branches of superconducting material in a loop, and a magnetic field generator which generates a time-varying magnetic field through the loop in a direction generally parallel to the axis of the loop. The magnetic field generator is selectively activated and de-activated to switch the electrical switch between a low-resistance state and a higher-resistance state. In the low-resistance state, there is no magnetic field through the loop and transport current flows through the loop. In the higher-resistance state, a magnetic field through the loop induces a screening current such that the sum of the transport current and the screening current is substantially equal to the critical current or is greater than the critical current of the superconducting material. The switch may be used in, for example, a rectifier or fault current limiter.

The invention discloses a critical current nondestructive testing device for a joint-free high-temperature superconducting tape. The critical current nondestructive testing device comprises a testing tape reel, a fixing plate, a testing tape reel motor rotating shaft, an air heater, a tension sensor, a wire guide wheel, a magnetizing device, a double-hole Hall sensor, a liquid nitrogen Dewar and the joint-free high-temperature superconducting tape. The test tape reel is used for placing the joint-free high-temperature superconducting tape; the testing tape reel motor rotating shaft is used for connecting the motor and the testing tape reel, and the air heater is used for blow-drying the tape to prevent the surface of the superconducting tape from freezing. The tension sensor is used for carrying out real-time and on-line monitoring on the tension applied to the superconducting tape. The wire guide wheel is of a bearing supporting structure and comprises a built-in deep groove ball bearing or sliding bearing. And the magnetizing device is used for magnetizing the high-temperature superconducting tape. The double-hole Hall sensor can detect magnetic field distribution on the surface of the magnetized strip. The double-hole Hall sensor is provided with a double-hole structure, and the slit strip is detected through the wire passing double holes.

The invention relates to the technical field of electric variable data compensation, in particular to a metering error dynamic compensation method and system of an intelligent measuring switch. The method comprises the following steps: calculating to obtain phase delay compensation time of each sampling point based on original instantaneous current of each sampling point, equivalent excitation inductance of a current transformer, internal resistance of a secondary side winding, resistance value of a sampling resistor and a magnetic circuit saturation critical current value; performing high-order correction on the original instantaneous current to obtain a real current value of the sampling point; based on the original instantaneous voltage, the real current value and the phase delay compensation time of the sampling point in the metering period, the active power of the metering period is calculated so as to realize metering error dynamic compensation, and the accuracy of active power calculation of the intelligent measurement switch in the dynamic load switching process can be effectively improved.

The invention discloses a magnetic electronic device for generating track torque by using a metal vanadium or titanium track Hall effect and a manufacturing method thereof. The device comprises a substrate, a track Hall structure containing a vanadium or titanium layer, and a heavy metal layer and a ferromagnetic layer which are adjacent to the track Hall structure, when a charge current passes through the vanadium or titanium layer, a transverse track current is generated based on the track Hall effect, and the track current is injected into the ferromagnetic layer and then converted into an effective track torque for controlling the magnetization state of the ferromagnetic layer. Preferably, the ferromagnetic layer has a perpendicular magnetic anisotropy. According to the invention, the light transition metal vanadium or titanium is used as the track Hall material, the experiment proves that a huge track Hall angle greater than 0.45 can be obtained, and meanwhile, the resistivity of the material is lower, so that the shunting phenomenon can be reduced in an actual device, and the critical current density for realizing write-in flipping can be obviously reduced. The device is simple in structure and compatible with an existing semiconductor process, and a brand new material platform is provided for developing a low-power-consumption and high-density magnetic random access memory (MRAM).

The invention discloses a grid-control superconducting nanowire low-temperature thermometer and a preparation method thereof, and relates to the technical field of superconducting electronics and low-temperature detection. Comprising a substrate and a superconducting layer, and the superconducting layer comprises a grid electrode, a superconducting nanowire and an inductor; the grid electrode is vertical to the superconductive nanowire, has a distance from the superconductive nanowire and is used for electric field regulation and control; the superconducting nanowire is connected with the inductor and is used for responding to particles injected into the grid electrode and outputting a pulse signal; the inductor is connected with the superconducting nanowire and is used for inhibiting a latch-up effect under high bias current; the superconducting layer material is a superconducting thin film material with a superconducting transition temperature Tc exceeding a measurement temperature zone; according to the invention, (quasi) particle injection in the critical current process of the superconducting nanowire is regulated and controlled through the grid electric field, high-precision measurement of the low temperature is realized in combination with nonlinear response of the pulse counting rate and the temperature, and the device and the method have the advantages of wide temperature zone measurement, low noise, high sensitivity, low power consumption, small self-heating, simple measurement system and low cost.

The invention provides a magnetic superconducting memory and a preparation method and a read-write method thereof. According to the magnetic superconducting memory, the superconducting layer maps the magnetization state by using the resistance difference between the superconducting state and the normal state; the ferromagnetic layer serves as a free layer capable of adjusting magnetization, and the magnitude of superconductive critical current of the superconductive layer is influenced through the magnetization direction. The heavy metal layer generates spin orbit torque through a spin Hall effect to drive the ferromagnetic layer to be magnetized and overturned; an infinite switching ratio between a superconducting state and a normal state is realized through a superconducting diode magnetoresistance effect, a high-efficiency and high-reliability nonvolatile storage scheme is realized in combination with a current-driven spin-orbit torque magnetization overturning technology, inherent defects of a traditional TMR are thoroughly overcome, and the signal contrast of a storage unit is remarkably improved; the heterostructure designed by the invention replaces a traditional magnetic tunnel junction, reduces material stacking and process complexity, and adopts a material compatible with a CMOS (Complementary Metal-Oxide-Semiconductor Transistor) process to promote large-scale integration of the low-temperature memory.

The invention discloses a high-temperature superconducting strip with non-uniform distribution of critical current density and a preparation method thereof, and belongs to the technical field of high-temperature superconducting materials. The critical current density of the high-temperature superconducting strip is non-uniformly distributed in the width direction, the current distribution of the high-temperature superconducting strip can be regulated and controlled according to requirements, the high-temperature superconducting strip comprises a high-temperature superconducting layer, the chemical formula of the high-temperature superconducting layer is Re < 1 + a > Ba < 2 + b > Cu < 3 + c > O < 7-d + x% (mol) BaMO3, and Re is selected from Y, Gd, Eu and Sm; m is selected from Hf, Zr and Sn; the preparation method comprises the following steps: depositing the high-temperature superconducting layer on the strip substrate; depositing a metal silver layer on the deposited strip; and carrying out heat treatment on the deposited strip in an oxygen environment, and carrying out laser heat treatment after slitting and / or copper plating. The critical current density of the high-temperature superconducting strip in the width direction is non-uniformly distributed and controllable, the failure risk of the strip is effectively reduced, and the service performance of the strip is improved.

The present invention relates to a high-temperature superconducting magnet and, more specifically, to: a high-temperature superconducting magnet achieving uniform critical current density using dissimilar metal wire materials; and a design parameter determination method thereof. To this end, in a high-temperature superconducting (HTS) magnet (100) formed by stacking an HTS coil (50) having a tape-type HTS conductor wire material wound thereon, the HTS coil (50) comprises: a first metal wire material (110) wound on the HTS coil (50); and a second metal wire material (130) that is made of a different metal from the first metal wire material (110) and wound while at least partially overlapping the first metal wire material (110) in the longitudinal direction of the first metal wire material (110), thereby forming a composite winding portion (140). Accordingly, the HTS magnet achieving uniform critical current density using dissimilar metal wire materials is provided, wherein the uniformity of the critical current density increases on the longitudinal cross-section of the HTS magnet (100).

The application discloses a method for improving critical current of REBCO superconducting layer and relates to the technical field of superconducting materials.The method for improving critical current of REBCO superconducting layer comprises the following steps: REBCO superconducting tapes are annealed in a pure oxygen atmosphere, quenched to 20-25 DEG C, and then the surface silver layer is removed by a chemical method, after which the REBCO superconducting tapes are annealed in a mixed atmosphere of ozone and oxygen, and a protective layer is deposited, so that the critical current of the REBCO superconducting layer is finally improved.The carrier concentration of the REBCO superconducting tapes can be effectively controlled through the specific multi-step oxidation process, so that the REBCO superconducting tapes break through the under-doped state commonly existing in the prior art, reach the over-doped level, and then the critical current performance of the tapes is significantly improved.The method has simple process, high stability and high industrial feasibility, and can meet the demand of higher current-carrying capacity of REBCO tapes in key fields such as power transmission and high-field magnets.

The invention provides a double-refrigeration device applied to high-temperature superconducting magnetic fluid propulsion, and relates to the technical field of high-temperature superconducting magnet cooling, the device comprises a magnet Dewar, a magnet liquid nitrogen cylinder, a fixing assembly and a conduction refrigeration system; the magnet liquid nitrogen cylinder is located in the magnet Dewar, one end of the fixing assembly is fixed to the side portion of the magnet liquid nitrogen cylinder, and the other end of the fixing assembly is fixed to the magnet Dewar; dewar protrusions are arranged on the circumferential side wall of the magnet Dewar, and the conduction refrigeration system is installed on the Dewar protrusions and exchanges heat with the superconducting magnet coil in the magnet liquid nitrogen cylinder. The superconducting magnet coil is also provided with a wiring port. The dual-refrigeration device provided by the invention breaks through the dilemma that the critical current cannot be tested after packaging, the liquid nitrogen cooling unit can independently, quickly and uniformly cool the packaged magnet, and the detachable sealing wiring port is arranged, so that the performance verification after packaging is realized, and the quality blind area is eliminated.

The invention discloses a CORC-CICC high-temperature superconducting conductor stability evaluation method and a related device. The method comprises the following steps: acquiring structural information of a CORC-CICC high-temperature superconducting conductor; according to the structural information of the CORC-CICC high-temperature superconducting conductor, determining the shunting temperature, the critical current, the minimum quenching energy and the quenching propagation speed of the CORC-CICC high-temperature superconducting conductor; and evaluating the stability of the CORC-CICC high-temperature superconducting conductor according to the shunting temperature, the critical current, the minimum quenching energy and the quenching propagation velocity of the CORC-CICC high-temperature superconducting conductor, and the method and the related device can evaluate the stability of the CORC-CICC high-temperature superconducting conductor.

The invention discloses a non-contact continuous nondestructive testing device and method for critical current uniformity of a high-temperature superconducting tape, which is applied to the field of superconducting material detection, and comprises an excitation magnet for generating a background magnetic field and exciting the high-temperature superconducting tape to generate magnetization current; the measuring probe consists of a magnetic circuit iron core, a fluxgate sensor and a copper strip compensation loop; the fluxgate sensor and the copper strip compensation loop are respectively connected with the control and measurement circuit through a fluxgate power supply acquisition circuit and a copper strip compensation loop power supply circuit; and the control and measurement circuit is used for implementing PID (Proportion Integration Differentiation) control through closed-loop negative feedback when the fluxgate sensor detects that the net residual magnetic flux in the magnetic circuit iron core is not zero, generating magnetic flux which is equal to and opposite to the high-temperature superconducting strip in size in the copper strip compensation loop, and calculating critical current according to current in the copper strip compensation loop when the net residual magnetic flux is zero. According to the method, rapid and accurate measurement of the critical current uniformity of the high-temperature superconducting strip without depending on a Hall sensor and calibration back calculation is realized.

The invention discloses a preparation method of a high-stability bronze-process niobium-tin wire, and relates to the technical field of superconducting wire preparation, and the preparation method comprises the following steps: assembling a composite ingot according to a composite structure which sequentially comprises an outer copper matrix, an outer barrier layer, a bronze-based CuNb layer, an inner barrier layer and an inner copper matrix from outside to inside; the composite ingot is sequentially subjected to heat preservation extrusion and multi-pass cold drawing, and a composite wire is obtained; carrying out heat treatment on the composite wire to obtain a Ni3Sn wire; the outer blocking layer and the inner blocking layer are made of Nb or Ta or Nb alloy or Ta alloy or Ta / Nb alternating composite layers. The Ni3Sn wire is prepared by designing a composite structure with double barrier layers and combining heat preservation extrusion, multi-pass cold drawing and heat treatment, the critical current density and the residual resistance ratio of the wire are increased, and then the stability of the wire is improved.

The invention discloses a superconducting material critical electrical characteristic prediction method and device and a medium, and relates to the field of material analysis, and the method comprises the steps: obtaining the actual working condition parameters and actual category labels of a to-be-predicted superconducting material; the actual working condition parameters comprise actual temperature, actual magnetic field intensity and actual magnetic field angle; performing prediction by utilizing a trained neural network according to the actual working condition parameters and the actual category labels to obtain critical electrical characteristics of the superconducting material; the critical electrical characteristics comprise critical current density and an n value; the trained neural network comprises an input layer, an embedded layer, a feature splicing layer, a hidden layer and an output layer which are connected in sequence; and the input layer is also connected with the feature splicing layer. According to the method, the electrical characteristics of the superconducting material can be efficiently and accurately predicted.

The application relates to a robust optimization design method of an airborne high-temperature superconducting generator, which comprises the following steps: a baseline design scheme is obtained by establishing a two-dimensional electromagnetic finite element baseline model and a total loss accounting model of the generator containing electromagnetic characteristics of superconducting coils; a feasible technical scheme set is obtained by performing scheme screening on pre-engineering hard constraints; an optimal candidate scheme is determined by performing fast optimization on the feasible domain by using a Taguchi orthogonal test, and the optimal candidate scheme is determined by main effect and range analysis or signal-to-noise ratio calculation; and a final design scheme is determined by taking the minimum performance fluctuation or the maximum signal-to-noise ratio as a criterion by introducing cold end temperature fluctuation, air gap assembly deviation, tape critical current dispersion and load and speed disturbance as noise factors for robust verification. The application can efficiently obtain an optimal design with high performance, strong engineering feasibility and operation robustness under limited simulation resources, and is especially suitable for a megawatt airborne high-temperature superconducting power generation system.

This application provides an audio processing method, an electronic device, and a computer-readable medium. The method includes detecting that a first frequency of a first audio signal to be processed belongs to a first frequency range; adjusting the amplitude of the first audio signal based on a first target amplitude corresponding to the first frequency to obtain a second audio signal; and providing the second audio signal to a piezoelectric loudspeaker to drive the piezoelectric loudspeaker to emit sound, wherein the current generated by the second audio signal input to the piezoelectric loudspeaker is lower than the critical current of overcurrent protection. This application can prevent the operating circuit of the piezoelectric loudspeaker from triggering overcurrent protection due to playing high-frequency audio signals.

This invention discloses a method for preparing Nb3Sn graphene composite superconducting absorbing material, comprising: preparing an Nb-Sn-Gr composite film using the sol-gel method; coating the Nb-Sn-Gr composite film onto a TaTi alloy rod and then loading it into a SnCu alloy tube, which is then loaded into a CuNb composite tube and drawn through multiple passes to obtain an inner-tin Nb3Sn subunit; loading the inner-tin Nb3Sn subunit into a Ta tube; uniformly filling the outside of the Ta tube with nitrogen-doped porous graphene-coated copper powder; loading it into an oxygen-free copper tube; and drawing through multiple passes to obtain the Nb3Sn graphene composite superconducting absorbing material. The Nb-Sn-Gr composite film and nitrogen-doped porous graphene-coated copper powder in this invention enable the Nb3Sn graphene composite superconducting absorbing material to maintain intrinsic superconducting properties such as high critical current density and upper critical field, while also possessing stable and efficient electromagnetic wave absorption capabilities under low temperature and strong magnetic field environments.

The application relates to the field of magnetic storage, in particular to a magnetic storage device, which comprises a fixed layer, a channel isolation layer and a free layer; the channel isolation layer is located between the fixed layer and the free layer; further comprising a non-magnetic layer, which is located on the free layer, and the material of the non-magnetic layer is different from that of the free layer. The application can effectively reduce the critical current for changing the magnetization direction of the free layer of the MTJ and reduce the volume of the magnetic storage device.

The application relates to a method and device for determining the breaking capacity of a vacuum switch device. The method comprises: obtaining critical current data of the vacuum switch device at each time when executing a simulation opening command; obtaining estimated current data of a target circuit to be cut off by the vacuum switch device; determining a target separation time range corresponding to the vacuum switch device; determining an adjustment strategy for adjusting the estimated current data according to the difference between the short-circuit current of the target circuit at each separation time within the target separation time range and the critical current data at the corresponding separation time; adjusting the estimated current data according to the adjustment strategy, and continuing the determination step of the adjustment strategy until the adjustment amount in the adjustment strategy is less than a preset adjustment amount, and determining the breaking capacity of the vacuum switch device according to the estimated current data when the adjustment amount is less than the preset adjustment amount. The method can improve the evaluation accuracy of the breaking capacity of the vacuum switch device.

The invention provides a superconducting thin film and preparation process equipment thereof. In the process equipment, a sputtering system and a substrate system are opposite up and down in a reaction chamber; the working gas inlet channel is located at the position, close to the target, of the shell of the reaction chamber, the reaction gas inlet channel is located at the position, close to the substrate system, of the shell of the reaction chamber, and the exhaust port is located in the shell of the side wall of the reaction chamber. The reaction gas inlet channel is arranged to be far away from the target material, the target poisoning phenomenon is avoided, and the magnetron sputtering efficiency and the superconducting thin film deposition rate are improved; meanwhile, the working gas inlet channel is arranged close to the target material, so that plasmas generated by the target material are more stable, and the critical temperature and the critical current density of the superconducting thin film material are enhanced; in addition, the reaction gas inlet channel is higher than the substrate, reaction products are prevented from depositing on the surface of the gas inlet channel, and the deposition rate of the superconducting film is improved. And finally, a working gas inlet channel is arranged to be lower than the target material, so that target material atoms are prevented from being sputtered by bombardment on the surface of the gas inlet channel to pollute the reaction chamber and the superconducting film.

The invention relates to a device for inducing a current flow in a load, also referred to as a flux pump. The device may comprise a rotor comprising at least one magnetic field generator configured to rotate with the rotor, one or more lengths of superconducting material arranged as an induction coil, a switch, and output terminals configured to connect to a load, the output terminals being connected in parallel with the switch. Rotation of the rotor may move the at least one magnetic field generator relative to the induction coil and switch, such that the magnetic field is periodically applied to the induction coil and switch to induce a current flow in the induction coil through the switch, and to reduce a critical current of the material within the switch, causing the switch to transition from a low-resistance state to a higher-resistance state.

The invention relates to a frequency-adjustable superconducting quantum coupler capable of naturally resisting magnetic flux noise, which comprises a DC-SQUIDs (Direct Current-Superconducting Quantum IDs), namely a superconducting ring consisting of two Josephson junctions, a bias control line for adjusting the critical current of the SQUIDs, and a capacitor or inductance circuit component adapted to adjust coupling parameters, the DC-SQUIDs are of a planar inner loop structure, the loop comprises two Josephson junctions, two arms of the SQUIDs are mutually crossed to form 2N identical superconducting loops, namely sub-loops, and N is a positive integer; the bias control line changes the magnetic flux in the loop by applying a bias magnetic field, so that the critical current of the SQUIDs is changed, and then the frequency of the superconducting quantum coupler can be regulated and controlled. In the process of actively adjusting the frequency of the coupler, the induced current of the N sub-loops in the SQUIDs flows clockwise, and the induced current of the other N sub-loops flows anticlockwise, so that a loop is integrally formed.

The invention relates to an Nb3Sn superconducting material, a method for improving the critical current density of Nb3Sn through rare earth yttrium doping and application of the Nb3Sn superconducting material. The method comprises the following steps that the surfaces of a component A and a component B are attached and placed in a fixing device to form a diffusion couple, and the diffusion couple is subjected to diffusion annealing to obtain the Nb3Sn superconducting material; the component A comprises an Nb elementary substance ingot and / or an Nb-Y alloy ingot; the component B comprises a Cu-Sn alloy ingot and / or a Cu-Sn-Y alloy ingot; at least one of the component A and the component B contains Y. By doping the Y element, the growth rate of the Nb3Sn layer is increased, and the critical current density of the interface Nb3Sn superconducting material is improved. The constructed diffusion couple can visually compare the growth difference of the Nb3Sn layers in doped and undoped samples, and facilitates the analysis of the influence mechanism of the doped elements on the synthesis of the Nb3Sn superconducting material and the critical current density.

Disclosed is a Josephson junction quantum mechanical device (200) comprising a first electrode (211) arranged on a substrate (201) and having a first elongated arm (221), and a second electrode (212) arranged on the substrate and comprising a second elongated arm (222). The first elongated arm and the second elongated arm extend toward each other to define an area of overlap (250). Furthermore, the first elongated arm and the second elongated arm each comprise, at the area of overlap, a respective first lateral flange (221 A, 222A). The first lateral flange (221 A) of the first elongated arm extends along a first lengthwise part (P1) of the first elongated arm and along a second lengthwise part (P2) of the second elongated arm, whereas the first lateral flange (222A) of the second elongated arm extends along a third lengthwise part (P3) of the second elongated arm and along a fourth lengthwise part (P4) of the first elongated arm. Thereby, the area of overlap is defined to comprise a surface area larger than a product of the respective widths of the first elongated arm and second elongated arm.

The invention relates to the technical field of anti-interference receiving, and discloses a tunable high-temperature superconducting amplitude limiter based on voltage regulation. Comprising a radio-frequency signal input end P1, a first impedance conversion node assembly, a superconducting amplitude limiting node L4, a direct-current bias regulation and control circuit for introducing bias current to the superconducting amplitude limiting node L4, a second impedance conversion node assembly and a radio-frequency signal output end P2 which are electrically connected in sequence, the first impedance conversion node assembly and the second impedance conversion node assembly are the same in structure, and each of the first impedance conversion node assembly and the second impedance conversion node assembly comprises a superconducting microstrip transmission line, a blocking capacitor and an impedance conversion node, on the premise that geometric structure parameters of the high-temperature superconducting amplitude limiting section are not changed, the working current density of the high-temperature superconducting amplitude limiting section can be changed within the range close to or away from the critical current density of the superconducting material by adjusting the magnitude of the bias current, and therefore tuning of the amplitude limiting threshold value and the power bearing capacity of the amplitude limiter is achieved.

The invention discloses a superconducting nanowire detector and a superconducting nanowire time-resolved single-photon spectrometer. The superconducting nanowire detector comprises a light response unit adopting a 1 * N discrete linear array structure, adjacent single detection units are spaced through delay lines, the delay lines on the two sides of the light response unit are connected with electrodes through gradient line units, and the gradient line units are arranged at the edge of the light response unit. Similar structure units which are in mirror symmetry with the gradual change line units are arranged on the two sides of the gradual change line units. The spectrometer comprises a displacement table, an optical fiber, an optical fiber focus lens, a diffraction grating, a focusing lens, the superconducting nanowire detector and a reading circuit. According to the detector, the current crowding effect can be avoided, the improvement of critical current and the reduction of dark count are realized, and the formation of an ultra-large-area superconducting nanowire linear array layout is facilitated. The spectrograph calibrates a spectrum through position mapping, wavelength information of incident light can be obtained only by measuring time difference, and the time resolution capability is achieved.

This invention discloses a method for evaluating the angle dependence of critical current in superconducting tapes, relating to the field of superconducting tape performance evaluation technology. The method includes: measuring the critical current values ​​of the superconducting tape at multiple magnetic field angles under constant environmental conditions; calculating the statistical average of the critical current values ​​and a quantitative index characterizing the dispersion of the data; and evaluating the angle dependence of the critical current of the superconducting tape based on the magnitude of the quantitative index. This method enables a quantitative comparison of the angle dependence of critical current in different superconducting tapes, is simple to calculate, has good versatility, and is suitable for superconducting tape design and material selection evaluation.

This invention relates to the field of superconducting material processing technology, specifically to a method for preparing Nb3Sn superconducting wires. The invention mainly involves inserting an Nb-Zr alloy into the exterior and / or center of a Sn-Cu single-core rod, filling the space between the Nb-Zr alloy and the Sn-Cu single-core rod with oxide powder, and then inserting it into a copper substrate. After multiple passes of stretching, forming, and length-cutting, Nb3Sn sub-components are obtained. These Nb3Sn sub-components are then uniformly arranged circumferentially within a copper tube to form a bundle, followed by multiple passes of stretching, heat treatment, and cutting to obtain the Nb3Sn superconducting wire. This invention enhances the critical current density of the Nb3Sn superconducting wire under high magnetic fields of 8T–16T by introducing an artificially pinned array with a density gradient distribution. This solves the problem of the matching effect produced by existing uniform artificially pinned center schemes, which limits the practical application of superconducting wires, and alleviates the decrease in critical current density of Nb3Sn superconducting wires under high fields.