59 results about "Dendrite (metal)" patented technology

The present invention provides a secondary battery that includes a metal ion receptor, which can absorb metal dendrites generated on the surface of a cathode while the battery is used, in a battery cell, whereby it is possible to improve safety by suppressing growth of dendrites and preventing a short due to a dendrite by making metal dendrites be absorbed in the metal ion receptor before the dendrites growing on the surface of the cathode reach the surface of an anode.

A composite membrane with nanostructured inorganic and organic phases is applied as an ion-selective layer to improve processability, prevent dendrite shorting, and increase power output of lithium-metal anodes through better Li-ion conductivity. Nanoconfinement, as opposed to macroscale confinement, is known to dramatically alter the properties of bulk materials. Control over a ceramic's size, shape, and properties is achieved with polymer templates. This is a new composition of matter and unique approach to composite membrane design.

The invention discloses a metal continuous casting process of electromagnetic excitation combined mechanical stirring. When the alloy melt is solidified, the electromagnetic excited combined mechanical stirring technology is used to generate microscopic and macroscale strong shear flow to break dendrites. In this way, the goal of refining the solidification structure, fully equiaxed crystallization, and reducing the degree of solute segregation can be achieved, thereby improving the performance of the alloy. The invention also provides a metal continuous casting device, which is realized by a device composed of a main crystallizer, a rotor stirring paddle, a runner, a program-controlled motor, a magnetic field generator, a coil, and a voltage-regulated and frequency-regulated AC power supply. The present invention uses the microscopic flow generated by electromagnetic excitation and the macroscopic flow generated by mechanical stirring to form a very complex chaotic flow, forming a strong shear flow, breaking dendrites, promoting the proliferation of crystal nuclei, reducing the temperature gradient, and obtaining ultra-fine Fully equiaxed crystal structure, while significantly reducing or even completely inhibiting the segregation of alloy elements, the energy consumption of the present invention is significantly lower than that of conventional electromagnetic stirring, and the energy saving effect is remarkable.

The invention discloses a simple back calculation method for measuring the heat transfer coefficient of a casting interface, comprising the steps of: 1) designing a standard casting structure; 2) designing a casting process scheme and molding the casting; 3) sampling different positions on the surface of the standard casting, And after numbering in sequence, do metallographic analysis to obtain the secondary dendrite spacing data of each sample; 4) Calculate the cooling rate corresponding to the secondary dendrite spacing of each sample; 5) Calculate the temperature field value of the casting process plan Simulation analysis, and set the initial interface heat transfer coefficient, extract the cooling rate of the mushy zone; 6) According to the back calculation principle, the cooling rate calculated by the experiment and the simulated cooling rate are fitted and back calculated to solve the required interface heat transfer coefficient. This method can effectively measure and back-calculate the interface heat transfer coefficient without the temperature measurement process, and is convenient to implement and has high accuracy. It is also a general method for the interface heat transfer coefficient of various casting methods.

The present invention has as its object to provide a spot welded joint and spot welding method which raise the fracture toughness of spot welded metal to raise the strength of the spot welded joint. In the present invention, there is provided a spot welding method comprising a melt zone forming step forming a melt zone by conduction and, after the melt zone forming step, a solidification step of running a current lower than the current run in the melt zone forming step so as to cause the melt zone to solidify, wherein, in the solidification step, electromagnetic vibration is applied to the melt zone, and a frequency fV of the electromagnetic vibration, a solidification speed νS when the melt zone solidifies, and an arm interval of dendrites λD when the melt zone solidifies satisfy 0.2≤νS / (λD·fV)≤4.0.

A framework of copper oxide dendrites is formed on a copper substrate, and these are then coated or plated with silver, gold, or an equivalent metal to create metal-coated dendrites with nano-structures, favorably in range of 50 to 200 nanometers. The framework of metal-coated dendrites are well suited for use in surface-enhanced Raman spectroscopy and other practical applications.

The invention discloses a continuous casting method for eliminating dendrite strip segregation near the surface of an alloy spring steel wire rod. The method comprises the control of the superheat degree of molten steel in a continuous casting tundish, the control of the casting speed of a continuous casting slab, and the control of electromagnetic stirring in a crystallizer. , crystallizer water flow control and vibration parameter control process; the superheat of molten steel in the tundish is controlled at 15-25°C through the electromagnetic induction heating equipment of the tundish; 150~300A, frequency 1.5~2.5Hz; adopt hydraulic vibration, amplitude 2.3~2.7mm, vibration frequency 100~130cpm, liquid level fluctuation is controlled within ±2mm. The φ5.5-20mm alloy spring steel wire rod produced by the continuous casting method of the present invention has no near-surface dendrite band segregation through dendrite corrosion detection, and the surface layer metallographic structure is uniform after heat treatment, effectively preventing the dendrite band segregation caused by dendrite band segregation. Early fatigue fracture of the spring.

The invention relates to a dendritic crystal etchant of a large ingot type modified IN617 alloy and a corrosion method thereof, belongs to the technical field of metallographic sample preparation, andsolves the technical problem that the existing etchant cannot corrode a clear dendritic crystal structure of the ingot type modified IN617 alloy in the prior art. The dendritic corrosion agent of thelarge ingot type modified IN617 alloy comprises 80-120 ml of concentrated hydrochloric acid, 9-15 ml of concentrated nitric acid, 100-130 ml of water and 10-20 ml of ethanol. The etchant provided bythe invention can rapidly and clearly corrode the dendritic structure in the as-cast state and the homogenized heat treatment state of the modified IN617 alloy, measure the dendritic spacing, measurethe components between dendrites and dendrite arms through energy spectrum, analyze the segregation degree of the dendrites, evaluate the elimination effect of the as-cast structure and the homogenized heat treatment of the modified IN617 alloy on the dendritic segregation, and provide an important basis for formulating the homogenization process before forging.

A method for cutting and preparing cast single crystal superalloy seed crystals. Based on the strict correspondence between the growth direction of single crystals and crystal directions, the directions of primary dendrites and secondary dendrites are precisely cut and calibrated, and standard dendrites are constructed based on the dendrite directions. The FCC crystal structure can cut out the (001) crystal plane of the single crystal test rod, and then use the crystal plane angle formula of the FCC crystal to calculate the angle θ between the target crystal plane and the (001) crystal plane, and according to the FCC crystal structure Features Mark the intersection line between the target crystal plane and the (001) crystal plane on the (001) crystal plane, and cut out the target crystal plane along the intersection line with an angle of θ with the (001) crystal plane; cut perpendicular to the target crystal plane A seed crystal with the target orientation is obtained. The invention adopts metallographic observation and directional cutting to directly cut seed crystals with any crystal orientation on cast single crystal test rods, has simple equipment and operation steps, and the orientation deviation of cut out seed crystals is less than 5°.