55 results about "Dendrite (crystal)" patented technology

The invention discloses a zinc foil preparation method for inhibiting zinc dendritic crystal growth, which comprises the following steps: carrying out laser texturing treatment on the surface of a pure zinc foil to generate a high-density ordered micro-pit array structure on the surface of the zinc foil, thereby greatly increasing the number of active sites on the surface of the zinc foil and eliminating the defects of scratches, pits and the like generated by the zinc foil; and carrying out alloying treatment on the zinc foil and a CuCl2 solution to generate a CuZn5 alloy layer so as to obtain the zinc foil for inhibiting dendritic crystal growth. The high-density ordered micro-pit array structure on the surface of the zinc foil eliminates the structural defects of the zinc foil, the increase of active sites and the introduction of the CuZn5 alloy layer can significantly reduce the desolventizing energy barrier in the charge transfer process and promote the Zn deposition / dissolution kinetics on the surface of the negative electrode, so that few by-products are formed in the treated negative electrode, and the service life of the negative electrode is prolonged. Therefore, the cycle performance of the treated zinc foil after the zinc foil forms a button cell is greatly improved, the service life of the zinc foil is obviously prolonged, and the economic benefit is particularly obvious.

A lead acid battery separator includes a porous membrane wherein within the porous membrane, a conductive element and / or a conductive or semiconductive nucleation additive is contained. According to the present invention, inside the battery separator, numerous nucleation sites are provided to provide starting points for crystal formation at numerous locations, thereby dispersing the total amount of lead sulfate into a large number of smaller crystals, rather than a small number of larger crystals; thus, these smaller crystals are more readily returned to the electrolyte during the charge cycle of the lead acid battery, thereby hindering the slowed growth of dendrites within the separator of the lead acid battery, increasing the charge acceptance of the battery, and / or improving the cycle performance of the battery.

The invention discloses an automatic segmentation method for a dendritic structure image of a laser cladding coating based on Dendritic Net. The automatic segmentation method comprises the following steps: S1, acquiring the dendritic structure image of the laser cladding coating by using a scanning electron microscope; s2, performing preprocessing, data annotation and data enhancement on the acquired image, constructing a dendritic structure data set, and dividing the data set into a training set and a verification set; s3, on the basis of a Pytorch framework, a dendritic structure image segmentation model Dendritic Net based on an HRNet model is established; s4, training the Dendritic Net model by using the training set in the dendritic structure data set, and checking the generalization ability of the Dendritic structure image segmentation model Dendritic Net by using the verification set; and S5, inputting a dendritic crystal structure image to be identified into the trained model, and identifying a dendritic crystal region and a dendritic crystal type in the image. According to the method, information of dendrites, blocky crystals and isometric crystals in the image is extracted in combination with a pixel segmentation method in a computer vision technology, and qualitative and quantitative characterization of the dendrite tissue structure of the laser cladding coating can be achieved.

The invention belongs to the technical field of laser welding defect prediction, and discloses an aluminum alloy laser welding seam three-dimensional solidification crack sensitivity prediction method, which comprises the following steps: accurately calculating a lap joint temperature / solid fraction (TB / fB) and a T-fS curve of adjacent dendrites of a polycrystalline structure in a welding seam pasty area through laser welding macro-micro thermal mass coupling simulation; a novel solidification crack sensitivity prediction method fusing microstructure information is provided, accurate prediction of the solidification crack sensitivity of aluminum alloy laser welding is achieved, the solidification crack inhibition mechanism that an ultra-fine equiaxed crystal structure shortens an intergranular liquid phase channel and reduces solute segregation is disclosed, and the stability of the solidification crack sensitivity is improved. The method has very important engineering application significance for realizing solidification crack-free welding of the high-strength aluminum alloy thick-wall component.

The invention relates to the technical field of electroplating, in particular to an ionic liquid aluminum plating method. The invention discloses an ionic liquid aluminum plating method. The frequency lt is adopted; and carrying out electroplating treatment by using a 50Hz pulsed power supply, wherein an electroplating solution is a chloroaluminate system ionic liquid. According to the ionic liquid aluminum plating method, the frequency lt is adopted; according to the invention, electroplating is carried out by using a pulse power supply with the frequency of 50 Hz, and aluminum ions can obtain sufficient growth time after nucleation and form a stable and compact crystal structure in cooperation with the chloroaluminate system ionic liquid, so that the problems of poor compactness, easy formation of loose dendritic crystals and weak leveling performance of an existing ionic liquid aluminum plating layer are effectively solved. And the prepared pure aluminum coating is flat and compact in surface, has no obvious defects, and is obviously superior to a coating prepared in the prior art.

The invention relates to a sublimation purification device which comprises an evaporation area and at least one condensation area, a rotatable spiral condensation assembly is arranged in a condenser in the condensation area in the axial direction, and the spiral condensation assembly comprises a central rotating shaft and spiral blades extending outwards; through continuous rotation of the spiral assembly, the geometric position of a condensation surface is forcibly changed, a crystal static growth boundary is broken to inhibit formation of loose dendritic crystals, and the dendritic crystals are prevented from touching a pipe wall to cause thermal short circuit and material overheating; in addition, a heat exchange medium runner is arranged in the spiral condensation assembly and comprises an outflow path extending from the central rotating shaft to the outer edge of the blade and a backflow path returning to the rotating shaft. According to the flow channel structure, the structural thermal resistance of long-range metal heat conduction is eliminated, full-surface isothermal cooling of an ultra-large-area spiral surface is achieved, a uniform and continuous cold source is provided while the assembly conveys materials, and finally long-term constancy and efficient and stable capture of condensation efficiency are guaranteed.

The invention discloses a NiCu alloy electrode preparation method based on electrochemical micromachining and electro-crystallization coordinated regulation and control, which comprises the following steps: (1) electrochemical micromachining: cutting a nickel net, clamping the longer end of the nickel net by using an electrode clamp with a platinum sheet, ensuring the effective area of an electrode immersed in an electrolyte, electrifying the nickel net in an acid solution, and carrying out electrochemical micromachining on the nickel net; cleaning and drying for later use; and (2) Ni-Cu gradient crystallization is conducted, specifically, nickel crystallization is conducted firstly, then copper crystallization is conducted, a Ni-rich compact bottom layer is formed in the initial stage of crystallization, a Ni-Cu mixed columnar crystal transition layer is formed in the middle stage of crystallization, and a Cu-rich nano dendritic crystal surface layer is formed in the later stage of crystallization. According to the preparation method, a multi-scale micro-nano composite structure is constructed through electrochemical micromachining, a micron framework-nano dendritic crystal composite structure is formed through Ni-Cu gradient crystallization, micron-scale gaps generated by electrochemical micromachining are filled, the NiCu alloy interface characteristics are optimized, the electro-catalytic performance is remarkably improved, and the method is close to a precious metal platinum catalyst.

To provide a molten Al-Zn-based plated sheet steel with excellent plating adhesiveness at a bending-back part even when a plating adhesion amount is large.SOLUTION: The present invention relates to a molten Al-Zn-based plated sheet steel, on which a plating layer having a composition containing 40-70 mass% of Al and 0.5-3.0 mass% of Si, and Zn and inevitable impurities at a remainder, is formed. The plating layer has a dendrite gap mainly containing dendrite made of Al primary crystal and Al-Zn eutectic crystal. The thickness X (μm) of the plating layer and the Vickers hardness HV0.01 of the Al primary crystal satisfy the following expressions (1) and (2). HV0.01≤-4X+205...(1) X≥23...(2)SELECTED DRAWING: Figure 4

The invention relates to a method for measuring dendritic crystal orientation deviation of a single crystal blade through monochromatic neutron diffraction imaging, which accurately captures crystal structure information through neutron diffraction, can clearly obtain diffraction signals of different areas of the single crystal blade, and can accurately measure the orientation deviation of defective crystal grains through the steps of defect position determination, bright spot matching and the like. By utilizing the deep penetrability and volatility of neutrons, the interior of the blade can be detected under the condition that the single crystal blade is not damaged. Meanwhile, the neutron imaging detection range is larger than that of a traditional X-ray method, overall imaging of the single crystal blade can be achieved, operation such as data cutting and splicing is not needed, the result is more visual and accurate, and consumed time is shorter.

The invention discloses a charge-discharge separation temperature control strategy for inhibiting dendritic crystal growth of a zinc-based flow battery, and belongs to the field of zinc-based flow batteries. The method is designed for solving the problem of zinc dendrite growth caused by non-uniform zinc deposition on the negative electrode side of the zinc-based flow battery, and an electrolyte in a storage tank of the zinc-based flow battery is charged at 15-30 DEG C, so that the uniformity of zinc deposition is improved, and the zinc dendrite growth is inhibited; and the electrolyte in the zinc-based flow battery storage tank is discharged at 35-45 DEG C, so that the mass transfer rate of reaction ions in the battery is improved, and the energy efficiency of the battery is improved. The method is applied to the zinc-based flow battery, the battery efficiency can be remarkably improved, meanwhile, the zinc deposition morphology is improved, and the service life of the battery is prolonged.

This invention provides a zinc foil surface treatment method for inhibiting dendrite growth, comprising: immersing a zinc foil with ultrasonically cleaned surface in an acidic mixture to obtain a zinc foil with a preferred zinc (002) crystal facet under acid etching; immersing the zinc foil with the preferred zinc (002) crystal facet in a mercaptosilane coupling agent solution, and through hydrolysis, forming a nanostructured zinc-silane composite layer on the zinc foil surface; and drying the zinc foil with the zinc-silane composite layer to obtain a zinc foil that can inhibit dendrite growth. The zinc foil surface treatment method for inhibiting dendrite growth described in this invention can generate a zinc-silane composite layer and zinc with (002) crystal facet orientation on the zinc foil surface. This composite layer has a strong zinc ion adsorption capacity, which can improve ion kinetics, promote uniform zinc plating and peeling, and the preferred (002) crystal facet can induce parallel growth of zinc metal and resist electrolyte corrosion, thereby effectively inhibiting zinc dendrites and stabilizing the electrode / electrolyte interface.

To provide a molten Al-Zn-based plated sheet steel with excellent plating adhesiveness at a bending-back part even when a plating adhesion amount is large.SOLUTION: The present invention relates to a molten Al-Zn-based plated sheet steel, on which a plating layer having a composition containing 40-70 mass% of Al and 0.5-3.0 mass% of Si, and Zn and inevitable impurities at a remainder, is formed. The plating layer has a dendrite gap mainly containing dendrite made of Al primary crystal and Al-Zn eutectic crystal. The thickness X (μm) of the plating layer and the Vickers hardness HV0.01 of the Al primary crystal satisfy the following expressions (1) and (2). HV0.01≤-4X+205...(1) X≥23...(2)SELECTED DRAWING: Figure 4

Method for measuring the crystalline misorientation of a single-crystal blade. Method for measuring the crystalline misorientation of a single-crystal blade (10) comprising a material formed of dendrites (30) having a main trunk (32) extending in a principal direction (Z') and branches (34), the method comprising defining a reference frame (XYZ) of the blade comprising a radial direction (Z), mechanical and chemical treatment of the blade (10) in a baseline (P1) to acquire a first image (I1) by microscopy, mechanical and chemical treatment of the blade (10) in a comparison plane (P2) radially offset from the baseline (P1) by a distance (D), to acquire a second image (I2) by microscopy, processing the first and second images (I1, I2) so as to compare the position of the main trunk (32) of each dendrite (30) between the two images (I1,I2) and thus deduce the orientation of the principal direction (Z') of the dendrites (30) with respect to the radial direction (Z). Figure for the abbreviation: Fig. 4.

The invention belongs to the technical field of preparation of cladding coatings on material surfaces, and particularly relates to a titanium alloy bearing material and a preparation method thereof. The titanium alloy bearing material comprises a titanium alloy substrate and a NiTi alloy coating cladding the titanium alloy substrate, and the NiTi alloy coating is composed of, by mass, 33-40% of Ti and the balance Ni; niTi structures at the joint of the NiTi alloy coating and the titanium alloy substrate are planar crystals and cellular crystals, and the NiTi structures above the joint are columnar crystals and columnar dendritic crystals. The NiTi structure with specific characteristics is formed on the surface of the titanium alloy substrate, the highest hardness reaches 677.41 HV0.2 and is 2.05 times that of the titanium alloy substrate, and the wear resistance is improved by 53% compared with that of the titanium alloy substrate. On the whole, the cladding coating effectively improves the wear resistance and the bearing capacity of the titanium alloy surface.

The invention provides a continuous preparation process of a rare earth copper alloy wire and the rare earth copper alloy wire. The continuous preparation process of the rare earth copper alloy wire comprises the steps of vacuum melting, horizontal continuous casting, nondestructive inspection, continuous extrusion and multi-stage continuous wire drawing which are conducted in sequence, the horizontal continuous casting is conducted under driving of a rotating magnetic field, the working frequency of the rotating magnetic field is 3-10 Hz, and the exciting current is 250-400 A. According to the method, horizontal continuous casting is carried out under driving of the rotating magnetic field, and forced convection driven by the rotating magnetic field can smash primary columnar dendritic crystals, increase nucleation cores and inhibit growth of columnar crystals, so that the rare earth copper alloy rod material with fine and uniform equiaxed crystal structures on the section is obtained; and through continuous extrusion and continuous multi-stage wire drawing treatment, dynamic recrystallization can be further promoted, the grain size of the rare earth copper alloy wire is smaller than or equal to 5 microns, distribution is uniform, and then more excellent strength, toughness and fatigue performance are achieved.

The application provides a preparation method of aluminum alloy dendrite crystals, the dendrite crystals prepared by the application are more single, do not interfere with each other, are more independent, are more complete, and grow more freely compared with the dendrite crystals obtained by other methods, do not compete with each other due to the change of cooling mode and cooling gradient direction, do not produce defects such as grain boundaries, and only grow downward in a single dendrite crystal mode, so that the application hopes to obtain complete single aluminum alloy dendrite crystals by the preparation mode, and further research whether the dendrite crystals also exist element segregation and the smallest unit of the dendrite crystals, and further provide theoretical support for the research on the secondary unit of the aluminum alloy dendrite crystals. The application avoids the limitation of the traditional alloy material production process, produces complete single aluminum alloy dendrite crystals, and provides feasibility support for the research on the aluminum alloy dendrite crystals.

The invention discloses a method for preparing a single-crystal high-temperature alloy seed crystal by using a five-axis water-jet guided laser processing system. The method comprises the following steps: S1, preparing a single-crystal high-temperature alloy test plate by combining a directional solidification process with a spiral crystal selection method; s2, after macroscopically corroding the single-crystal high-temperature alloy test plate, measuring included angles alpha and beta between dendrites on two side surfaces of the single-crystal high-temperature alloy test plate and a single-crystal growth direction; then, carrying out chemical corrosion on the cross section of the single-crystal high-temperature alloy test plate, and measuring included angles A and B between secondary dendrites on the cross section and the horizontal axial direction; s3, calculating direction vectors of primary dendritic crystals and secondary dendritic crystals of the single-crystal high-temperature alloy test plate; s4, according to the direction vectors of the primary dendritic crystal and the secondary dendritic crystal of the single-crystal high-temperature alloy test plate, the direction vector of the target seed crystal orientation is calculated; and S5, clamping the single-crystal high-temperature alloy test plate on a workbench of a five-axis water-jet guided laser processing system, and carrying out directional cutting by adopting the five-axis water-jet guided laser processing system to obtain a target seed crystal.

The invention provides an ultrahigh corrosion-resistant zinc-aluminum-magnesium steel strip which comprises a cold-rolled or hot-rolled acid flat substrate and a plating layer plated on the substrate, the plating layer takes zinc (Zn) as the balance and comprises the following chemical components in percentage by mass: 17-23% of aluminum (Al), 5-9% of magnesium (Mg), 0.23 + / -0.05% of silicon (Si), 0.04 + / -0.02% of titanium (Ti), 0.3 + / -0.2% of cerium (Ce), 0.14 + / -0.2% of calcium (Ca) and 0.17 + / -0.2% of tin (Sn); the coating is controlled to form a compact network-shaped structure which takes Fe2Al5 as a crystal nucleus, Al crystal dendrites and MgZn2 secondary crystal dendrites grow in a staggered manner and is connected by Mg2Si, and the compact network-shaped structure is finally wrapped by a Zn phase, so that uniform distribution of a magnesium element in the coating is ensured, and a material basis is provided for a dual protection and self-repairing mechanism.

The present application belongs to the technical field of metal additive manufacturing and solidification structure regulation, and particularly relates to a laser powder bed fusion forming method of a directional columnar grain structure alloy. The present application adopts a flat-top beam or a point-ring beam as a forming laser beam, inputs a single-channel three-dimensional transient heat transfer solidification model, obtains a molten pool width, a molten pool depth, a temperature gradient, a solidification rate and a columnar grain-equiaxed grain transition determination result, screens laser power and scanning speed according to the molten pool morphology with a width-depth ratio W / D>3; sets a scanning interval according to the deviation area of the molten pool side temperature gradient vector relative to the preset columnar grain growth direction, so that the overlapping area of adjacent melt channels covers different orientation dendrites or grains on the side; sets the powder layer thickness according to the sensitive area of the columnar grain-equiaxed grain transition at different heights, so that the remelting of the subsequent layer molten pool eliminates the mixed crystals, equiaxed crystals or non-target oriented grains on the top of the previous layer molten pool, and a columnar grain structure metal alloy component is obtained through continuous directional growth across the melt channel and across the layer.

The application discloses a preparation method of in-situ controllable inorganic salt micro-nano dendritic crystals based on Tris-HCl buffer solution, which comprises the following steps: adjusting the pH value of the Tris-HCl buffer solution by NaOH to generate NaCl in-situ and obtain a precursor solution; and adding the precursor solution on a solid substrate with surface energy modification and evaporating and drying in a constant temperature and humidity environment to spontaneously induce the generation of NaCl micro-nano dendritic crystals with dendritic micro-nano fractal pattern characteristics. The application utilizes the NaCl generated by the in-situ neutralization reaction between NaOH and the original acidic component in the buffer solution as a skeleton material, relies on the high viscoelastic quasi-crystalline network formed by the concentration of the organic medium, breaks the isotropic growth balance of NaCl through space steric adsorption, and realizes the controllable self-assembly of the dendritic crystals. The method has low cost and simple operation, and can control the micro-nano structure of the deposit by only adjusting the contact angle of the substrate surface or the initial concentration of the Tris-HCl, thereby providing a new self-assembly technical approach for the efficient enrichment, directional arrangement and fluorescence enhancement detection of trace biomarkers in biochips.

The present application relates to the technical field of metal component additive repair, and particularly relates to a hydraulic turbine guide vane repair remanufacturing method based on electric arc additive, which adopts a process of electric arc additive combined with mechanical vibration energy field, acquires acceleration and temperature signals in real time during deposition, and adjusts vibration parameters and dynamically controls heat input to stabilize interlayer temperature in a closed loop and self-adaptively; in-situ depth cooperation of the energy field and the temperature field makes continuous mechanical vibration kinetic energy strongly break coarse ferrite dendrites; controlled interlayer cooling rate effectively blocks secondary growth of small crystal nuclei, which greatly releases constraint thermal stress of the multilayer stacked repair area, makes microstructure into extremely short strip or point structure, greatly reduces macroscopic warping deformation in the repair process, and finally gives the hydraulic turbine guide vane excellent strength and toughness matching and long-term service safety and reliability.

The invention relates to the technical field of brazing, and discloses Yb and Tb co-doped alloy brazing filler metal, a preparation method and a brazing process. The Yb and Tb co-doped alloy brazing filler metal comprises, by mass, 12%-13% of chromium, 3%-4% of boron, 3%-4% of silicon, 4%-5% of iron, 0.5%-2% of terbium, 0.5%-1.5% of ytterbium and the balance nickel. Yb and Tb co-doping effectively inhibits growth of dendrites, rare earth elements are easily enriched at the grain boundary to form a fine isometric crystal structure, the prepared Yb and Tb co-doped alloy brazing filler metal brazed diamond is smaller in thermal damage degree, the brazed surface is smooth and free of accumulation, and the phenomena of wrinkles and holes are reduced to a great extent. The rare earth co-doping is beneficial to improving the wettability of the brazing filler metal, the brazing filler metal and the diamond are subjected to violent chemical metallurgy, the interface bonding strength of the brazing filler metal and the diamond is improved, and therefore the machining performance of a diamond tool is improved.

The invention provides a method for reducing residual stress of a 3D printing aluminum-based composite material through ultrasonic assistance, and belongs to the technical field of 3D printing. The method comprises the steps that the 3D printing aluminum-based composite material is prepared, a composite material model is constructed, an ultrasonic-free 3D printing process is simulated, an ultrasonic-assisted 3D printing process is implemented, a microstructure and stress are analyzed, and optimal ultrasonic parameters are determined. Converting the simulation parameters into actual process parameters; the atomic-scale interaction mechanism of an ultrasonic field and a material is accurately analyzed by means of molecular dynamics simulation, ultrasonic vibration is introduced in the key cooling stage, molten pool fluid dynamics is changed through the acoustic streaming effect, the columnar crystal growth inhibition rate is increased, isometric crystal formation is promoted, dendritic crystals are broken through microjet generated by the cavitation effect, the grain boundary area is increased, and stress concentration is dispersed; through quantitative analysis of a dislocation movement track, it is found that the dislocation migration rate is increased and the entanglement density is reduced through ultrasound, the average residual stress of the model is reduced, the peak stress is reduced, and the efficiency is greatly improved.

The utility model provides a device for inhibiting dendritic crystal growth of a zinc-air battery, and relates to the field of energy storage batteries. Comprising an electrolyte storage tank and a zinc-air battery, the electrolyte storage tank and the zinc-air battery are communicated to form a closed loop, electrolyte flows into the zinc-air battery from the electrolyte storage tank and then flows back to the electrolyte storage tank to realize circulation, the zinc-air battery is connected with a blue electricity testing system, and the blue electricity testing system performs charging and discharging testing. The diagonal flow state electrolyte disclosed by the utility model can effectively inhibit the growth of zinc dendrites, prolong the service life of the battery and reduce the short-circuit risk of the battery.

The invention relates to the technical field of energy storage batteries, and particularly discloses an electrolyte for inhibiting zinc dendrite growth and application thereof. The electrolyte consists of electrolyte zinc salt, sodium lactate and water, and is beneficial to inhibiting Zn dendritic crystals and reducing the reaction rate of hydrogen precipitation. Besides, lactic acid anions (SC-) are more easily combined with water, so that a solvation shell structure of Zn < 2 + > is destroyed, deposition of Zn < 2 + > is more uniform, side reactions are reduced, and the zinc metal electrode can stably circulate for more than 500 hours under the condition of 5 mA cm <-2 >. Growth of zinc dendrites can be remarkably inhibited, the service life of the zinc metal negative electrode is prolonged, and the method has the advantages of being simple in preparation process, low in cost and good in application prospect.

The invention relates to a control method for growing a single crystal blade by using secondary dendrites, and relates to the technical field of high-temperature alloy precision casting. The invention provides a control method for a secondary dendrite growth single crystal blade. The control method comprises the following steps: (1) preparing a secondary orientation seed crystal; (2) pressing a seed crystal mold; (3) preparing a module shell; and (4) smelting and melt-injecting to prepare the single crystal test bar meeting the design requirements. The seed crystal of the secondary dendritic crystal is prepared by using the secondary dendritic crystal as the initial stage of the seed crystal to grow the single crystal blade. By using the seed crystal to grow the single crystal test bar, the success rate of the seed crystal to grow the single crystal test bar is effectively improved.

The invention discloses a uranium dendritic crystal growth prediction method in a uranium electrolytic refining process based on a phase field method, and belongs to the field of spent fuel aftertreatment. Establishing a phase field model for predicting uranium dendritic crystal growth according to a phase field control equation derived by electrochemical reaction thermodynamics and a free energy function; performing dimensionless processing on the phase field control equation, and inputting the equation into simulation software; determining a phase field simulation domain, performing grid division, and setting an initial crystal nucleus position; setting uranium dendritic crystal phase field model parameters, boundary conditions and solving conditions, determining a specific mathematical relationship between the phase field model parameters and macroscopic measurable parameters through an analytical method, and solving the input control equation by using software; and outputting a result, and carrying out visual treatment to obtain the uranium dendritic crystal growth morphology in the uranium electrolytic refining process. According to the method, uranium dendritic crystal growth prediction under different process parameters such as constant potential, constant current and pulse electrolysis can be achieved, the growth mechanism of uranium dendritic crystals can be comprehensively understood, and time cost and capital investment are saved.

The invention discloses a battery dendritic crystal monitoring method, system, equipment and product based on ultrasonic guided waves, and the method comprises the steps: employing a piezoelectric transducer to excite SH0 ultrasonic guided waves in a normal charging and discharging state of a battery, and enabling the SH0 ultrasonic guided waves to be transmitted along the surface of an electrode or a waveguide structure which is tightly coupled with the electrode, and high-precision acquisition and analysis are carried out on reflection and transmission echo signals. And carrying out guided wave feature extraction on the echo signal to obtain key parameters such as guided wave propagation time, speed drift and energy attenuation, so as to realize real-time and high-sensitivity monitoring of the process from early stage initiation and growth to irreversible accumulation of the crystal dendrites. And in combination with a signal processing algorithm and a threshold criterion, a quantitative characterization and early warning mechanism of crystal dendrite evolution is constructed, so that the safety risks that the crystal dendrite pierces the diaphragm and internal short circuit occurs are reduced. The nondestructive detection monitoring method can provide powerful technical support for battery safety management, life prediction and battery management system linkage control.

The invention discloses a method for preparing a high-performance beryllium-aluminum composite material by adopting high-frequency pulsed arc additive manufacturing, and relates to an additive manufacturing method of a beryllium-aluminum composite material. The invention aims to solve the problem that the mechanical property of the prepared beryllium-aluminum composite material is poor due to the fact that the length-diameter ratio of beryllium dendrites in the beryllium-aluminum composite material prepared in the electric arc additive manufacturing process is extremely high. According to the method, an alternating magnetic field is generated in a molten pool through high-frequency pulse current, periodic Lorentz force is formed to drive strong convection of a melt, shearing force is applied to growing dendritic crystals, so that dendritic crystal arms are broken, the length-diameter ratio of the pre-solidified beryllium dendritic crystals is greatly reduced, a molten aluminum infiltration channel is shortened, the shrinkage porosity defect is greatly reduced, and the service life of the molten aluminum is prolonged. The mechanical property is improved. The fractured dendritic crystal fragments form a high-surface-energy interface in the melt, the nucleation energy barrier is reduced, a preferential attachment point is provided for melt atoms, a heterogeneous nucleation core is provided, then grain refinement is achieved, and the mechanical property of the beryllium-aluminum composite material is further improved.

Method for measuring crystal disorientation of a monocrystalline blade Method for measuring crystal disorientation of a monocrystalline blade (10) comprising a material formed of dendrites (30) having a main trunk (32) extending in a main direction (Z') and branches (34), the method comprising defining a reference frame (XYZ) of the blade comprising a radial direction (Z), mechanically and chemically treating the blade (10) in a base plane (P1) to acquire a first image (I1) by micrography, mechanically and chemically treating the blade (10) in a comparison plane (P2) radially offset from the base plane (P1) by a distance (D), to acquire a second image (I2) by micrography, processing the first and second images (I1, I2) so as to compare the position of the main trunk (32) of each dendrite (30) between the two images (I1,I2) and thus deduce the orientation of the main direction (Z') of the dendrites (30) with respect to the radial direction (Z). Figure for the abstract: Fig. 4.,