23 results about "Dendrite (crystal)" patented technology

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 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.

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.

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 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 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 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 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 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 belongs to the technical field of metal additive manufacturing, and discloses an auxiliary energy field compounding method for refining electric arc additive aluminum alloy grains. The method comprises the following specific steps: constructing a composite energy field system, setting magneto-acoustic frequency domain parameters to avoid interference, driving melt to macroscopically stir by utilizing an alternating magnetic field Lorentz force, simultaneously exciting ultrasonic waves to generate a cavitation effect to crush dendritic crystals, and transporting crushed crystal particles to a whole molten pool by virtue of magnetic flow, and finally, magnetic field and ultrasonic time sequence coupling control is carried out in the solidification stage. Through cooperation of magnetic control macroscopic stirring and ultrasonic microcosmic cavitation and fluid transportation, the defects that the action range of a single energy field is limited, and refining is not thorough are overcome, grain ultra-refining and structure homogenization of the whole area of the electric arc additive aluminum alloy component are achieved, the mechanical property is remarkably improved, anisotropy is reduced, and the air hole defect is reduced.

The present invention relates to a method for measuring the crystal orientation difference of a single-crystal blade (10), the blade (10) comprising a material formed of dendrites (30) having a trunk (32) and branches (34) extending in a principal direction (Z'), the method comprising: defining a reference coordinate system (XYZ) for the blade, the reference coordinate system including a radial direction (Z); mechanically and chemically treating the blade (10) in a base plane (P1) to acquire a first image (I1) by photomicrography; mechanically and chemically treating the blade (10) in a comparison plane (P2) offset radially from the base plane (P1) by a distance (D) to acquire a second image (I2) by photomicrography; and processing the first and second images (I1, I2) to compare the position of the trunk (32) of each dendrite (30) in the two images (I1, I2) and thereby derive the orientation of the principal direction (Z') of the dendrite (30) relative to the radial direction (Z).

This invention relates to a dendrite-free zinc electrode for electrochemically mediated amine regeneration, its preparation method, and its application. The invention modifies an electrolyte containing diethylenetriamine, zinc chloride, and potassium chloride using electrolyte additives with carboxyl functional groups (such as sodium maleate, thiosalicylic acid, and ammonium formate). These carboxyl functional groups selectively adsorb onto the zinc electrode surface, enhancing the binding ability of zinc ions to the low surface energy (002) crystal plane of zinc. This guides zinc ions to preferentially deposit along the (002) crystal plane, constructing a flat and dense zinc deposition layer, ultimately effectively inhibiting zinc dendrite growth. A dendrite-free zinc electrode with a high proportion of preferentially oriented Zn (002) crystal planes is prepared by constant current electrodeposition in an electrolyte containing diethylenetriamine, zinc chloride, and potassium chloride. The prepared electrode surface is dense and flat, dendrite-free, with a significantly improved relative texture coefficient of the Zn (002) crystal plane, reduced CO2 desorption energy consumption, and improved corrosion resistance and hydrogen evolution inhibition capabilities. The present invention features a simple process, mild conditions, and low cost, and is suitable for electrochemically mediated amine regeneration carbon capture systems.

3D-printed metal objects with large-size cubic crystal structures are produced by controlling the infill distance and molten pool depth. A molten pool is moved within a first powder layer along a first scan pattern to create a first patterned layer. The scan pattern has parallel scan lines spaced apart by an infill distance along an infill direction perpendicular to the scan lines. As the molten pool cools, dendrites grow in their dendrite growth direction. This infill distance promotes dendrite growth in directions orthogonal to the scan lines and suppresses dendrite growth in directions with a directional component opposite to the infill direction. A second patterned layer is created by moving the molten pool within a powder layer on top of the first patterned layer. The pool depth suppresses dendrite growth in the first patterned layer at an angle of less than 45 degrees relative to the top surface of the molten pool.

The invention discloses a beryllium aluminum alloy solidification simulation method coupling solute transmission and structure evolution, and relates to the field of alloy solidification simulation. Comprising the following steps: determining a 12-growth-direction model of beryllium dendrites with an HCP structure according to an X-ray microscopic tomography result; acquiring material parameters; establishing a three-dimensional solidification calculation domain and carrying out grid division; calculating and solving mass, momentum, energy and solute transfer equations required during solidification; and calculating an analysis result, comparing the analysis result with an experimental result, and outputting the result. According to the method, the 12-growth-direction model suitable for the three-dimensional HCP crystal structure is established, the three-dimensional space morphology and growth orientation of the alpha-Be dendritic crystal can be accurately described, the space orientation of the alpha-Be dendritic crystal and the growth behavior of the alpha-Be dendritic crystal under the action of a flow field can be accurately described, and the solidification structure prediction precision is remarkably improved.

The present application relates to the technical field of additive manufacturing, and discloses an additive manufacturing heat-crack-free precipitation-strengthened high-temperature alloy and a preparation method thereof. The present application divides the layer into a plurality of mutually parallel scanning strips according to a preset translation direction and scanning strip interval, and performs strip scanning by means of laser self-rotation + translation motion coupling, thereby significantly enhancing the molten pool disturbance, realizing periodic shearing fracture of dendrite tips, breaking the columnar crystal epitaxial growth, realizing grain equiaxialization, and weakening anisotropy. In addition, the laser scanning is a high-speed scanning strategy with a translation speed greater than or equal to 1500 mm / s, shallow molten pools are formed by high-speed scanning, the surface tension in the shallow molten pool is utilized to strengthen the internal convection of the molten pool, the dendrites are refined, the formation of columnar crystals in the high-temperature alloy is further reduced, the anisotropy of mechanical properties is significantly eliminated, and the transverse strength and creep resistance under high temperature are improved. Equiaxed grains can effectively hinder the directional propagation of cracks along the columnar grain boundary, thereby significantly enhancing the fatigue life and damage tolerance.

The application 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 vacuum smelting, horizontal continuous casting, nondestructive testing, continuous extrusion and multi-stage continuous wire drawing in sequence, wherein the horizontal continuous casting is performed under the driving of a rotating magnetic field, the working frequency of the rotating magnetic field is 3-10 Hz, and the excitation current is 250-400 A. In the application, the horizontal continuous casting is performed under the driving of the rotating magnetic field, the forced convection of the rotating magnetic field driving can break the nascent columnar dendrites, increase the nucleation core and inhibit the growth of columnar crystals, so that the rare earth copper alloy rod material with fine and uniform equiaxed crystal structure on the cross section is obtained, and the dynamic recrystallization is further promoted through the continuous extrusion and the continuous multi-stage wire drawing, so that the grain size of the rare earth copper alloy wire is less than or equal to 5 microns and is uniformly distributed, and thus more excellent strength, toughness and fatigue performance are brought.

The application belongs to the technical field of single crystal alloy preparation, and particularly relates to a method for ultrasonic-assisted preparation of single crystal alloy. The application introduces an ultrasonic-induced sound field and flow field in a directional solidification process, effectively controls the solute boundary layer thickness near a solidification interface, successfully realizes controllable conversion of high-temperature alloy from cellular crystal to steady-state dendrite under columnar crystal conditions, and significantly refines dendrite primary arm spacing. The application breaks through the limitation of traditional directional solidification on solidification structure size, provides a new technical path for preparation of high-performance high-temperature alloy, and comprehensively improves the application performance of metal materials.

The application provides a method for preparing a single-crystal high-temperature alloy blade by using a seed crystal, comprising the following steps: S1) preparing a shell mold set of the single-crystal high-temperature alloy blade, so that the seed crystal and the shell of the shell mold set are in gapless contact; S2) placing the shell mold set on a water-cooled crystallizer, and after the shell mold set is heated, pouring single-crystal high-temperature alloy liquid into a cavity through a transition runner cavity of a pouring system to reduce the speed of the single-crystal high-temperature alloy liquid entering the cavity, and obtaining the single-crystal high-temperature alloy blade after directional solidification. The method for preparing a single-crystal high-temperature alloy blade by using a seed crystal provided in the application eliminates the gap between the seed crystal and the shell, and introduces a transition runner cavity to control the alloy liquid filling process of the cavity, so that the seed crystal part of the remelted region tends to be static and stable, the grain proliferation caused by the fragmentation of the dendrites in the remelted region is reduced, and the success rate of single-crystal seeding is significantly improved.

The application discloses a preparation method and application of a zinc oxide-based hydrated cerium carbonate oxide composite material, in particular to a preparation method and application of a Ce2O(CO3)2H2O / ZnO composite material, wherein the preparation method comprises the following steps: preparing a salt solution, preparing an alkali solution, ultrasonic mixing of the salt solution and the alkali solution, pH adjustment, aging, washing and drying of the product; the method provided by the application is used for preparing a zinc-nickel battery negative active material and inhibiting the growth of dendrites; compared with physical mixing, the hydrothermal method can effectively control the reaction and the crystal growth by changing the temperature, the pressure and the reaction time, so that the Ce is better grown on the surface of the ZnO, and the Ce2O(CO3)2H2O / ZnO composite material with better crystallinity is generated; the Ce2O(CO3)2H2O / ZnO composite material prepared by the method has a larger specific surface area and higher catalytic activity compared with traditional ZnO.