7 results about "Field cooling" patented technology

The present invention relates to a multi-connected high-temperature superconducting magnet based on ReBCO-coated superconducting sheets that can simultaneously generate multiple magnetic induction intensities. The superconducting magnet is formed by alternately stacking and fixing one or more sets of superconducting ring sheets and insulating sheets. Several connected circular ring structures with successively decreasing radii are cut out on the superconducting sheets and insulating sheets, and the circular ring structures at corresponding positions have the same size. The present invention adopts a superconducting sheet stacking method, eliminating the bending and winding steps to reduce the impact on the performance of the superconducting tape; at the same time, the device adopts the existing "field cooling method" for excitation, without the need for welding, power supply and current leads, reducing operating costs and heat leakage, and has the advantages of compact structure, detachability, high stability and simple preparation process; it can stably output multiple stable magnetic fields with different magnetic induction intensities, expanding the scope of application of ReBCO superconductors in magnets, and can also be applied to application scenarios such as medium and large superconducting magnets.

The application discloses a copper-embedded multilayer board defect detection method and system based on eddy current thermal imaging and impedance spectrum fusion, relates to the technical field of multilayer board defect detection, and comprises the following steps: applying a high-frequency alternating pulse magnetic field to a copper-embedded multilayer board to be detected; continuously collecting thermal field cooling sequence images after pulse excitation, then extracting thermal diffusion coefficients of copper-embedded regions a and thermal field isotheral line distribution characteristics; using test probes of an automatic machine to contact copper-embedded blocks and corresponding network test points on the copper-embedded multilayer board to be detected, injecting a wideband sweep signal, obtaining impedance spectrum and extracting characteristic parameters; and a , thermal field isotheral line asymmetry, Z LF , R HF and Δ θ are constructed into a multi-dimensional feature vector, input into a fusion judgment model, and a judgment result of the copper-embedded multilayer board defect is output according to a preset multiple threshold. The application realizes non-destructive defect detection, and the micro-crack detection rate is about 97%, and the copper-embedded offset and interlayer short-circuit detection rate is 100%.

The invention belongs to the technical field of condensed state physics and material research, and particularly relates to a heavy rare earth transition metal oxide magnetocaloric material screening method which comprises the following steps: obtaining zero field cooling of a test sample and a magnetization intensity-temperature curve of the field cooling, and deriving the magnetization intensity-temperature curve of the field cooling to obtain a magnetic field temperature curve of the field cooling; then the absolute value of the derivative of the field cooling magnetization intensity-temperature curve is obtained, and an absolute value curve is obtained; calculating an average magnetic phase transition temperature based on the absolute value curve; calculating the variance of the absolute value curve at the average magnetic phase transition temperature; calculating the dimensionless variance of the absolute value curve based on the variance of the absolute value curve at the average magnetic phase transition temperature; obtaining an isothermal magnetization curve of the test sample and calculating a magnetic entropy change value; and based on the dimensionless variance value, establishing a quantitative relationship between the magnetic phase change interaction intensity and the magnetic entropy change value, and further screening out a target sample. And theoretical support is provided for development and physical mechanism analysis of the low-temperature heavy rare earth based giant magnetocaloric material.

The utility model provides calendering equipment for PVC artificial leather processing, and relates to the technical field of artificial leather processing equipment. Comprising two supporting vertical plates, operation tables are fixedly connected to the tops of the two supporting vertical plates, an inner mounting cavity, a field cooling box, a limiting plate and an auxiliary transmission mechanism are arranged, artificial leather placed in the inner mounting cavity, the field cooling box, the limiting plate and the auxiliary transmission mechanism is calendered, and a first driving motor runs to drive recycling equipment to rotate; the artificial leather is stored in the classified storage cavities at different positions inside the field cooling box, storage and placement treatment during use are facilitated, workers can take the artificial leather normally conveniently, a fan is installed inside the field cooling box, the calendered artificial leather is stored in a classified mode through cooperation, remote monitoring and management are taken into consideration, and the working efficiency is improved. And meanwhile, auxiliary cooling treatment can be conveniently carried out on the site, the labor intensity of manual cleaning is reduced while the service life of the equipment is prolonged, the use flexibility of the whole equipment is improved, and the use requirement is met.

The utility model provides a single crystal furnace thermal field lifting unit, a single crystal furnace thermal field lifting device and a single crystal furnace, and aims to solve the technical problem that the thermal field cooling time is long after the existing single crystal furnace is shut down. The single crystal furnace thermal field lifting device comprises a plurality of single crystal furnace thermal field lifting units installed on a furnace bottom plate, and each single crystal furnace thermal field lifting unit comprises a lifting mechanism arranged at the bottom of a single crystal furnace; one end of the supporting rod is connected with the lifting mechanism, and the other end penetrates through the furnace bottom plate, the bottom felt and the lower thermal insulation cylinder to be connected with the middle thermal insulation cylinder; wherein the lifting mechanism is in driving connection with the supporting rod, and the supporting rod can be driven by the lifting mechanism to move upwards, so that a heat dissipation gap is formed between the middle heat preservation barrel and the lower heat preservation barrel. According to the single crystal furnace thermal field lifting device, the thermal field heat preservation structure is changed after production shutdown, the thermal field is prompted to be rapidly cooled, the thermal field cooling time is effectively shortened, and the single crystal production efficiency is improved.

The application discloses a kind of synergistically improves SrFeO 3‑δ Method of cubic perovskite structure spontaneous exchange bias effect relates to functional material preparation technical field.The method of the present application is by high-temperature solid-phase sintering,Er ions are doped in the Sr site of SrFeO 3‑δ Gradient magnetic Co ions are doped in the Fe site of SrFeO 3‑δ SrFeO 3‑δ Cubic perovskite structure with improved spontaneous exchange bias effect;The preparation process of the application is simple, the production cost is low, and the SrFeO 3‑δ Cubic perovskite structure prepared still can be offset along the magnetic field axis under zero magnetic field cooling condition, can realize stable unidirectional pinning effect without complex multilayer film structure or field cooling treatment, and is important to expand SrFeO 3‑δ Cubic perovskite oxide application field, improve device performance and promote the development of related scientific research.