32 results about "Periodic composites" patented technology

A solid state laser comprises a pumping source, a pumping tail fiber, and a first coupling lens, a second coupling lens, a pumping-end cavity lens, a laser gain medium and an output cavity lens arranged in the pumping laser output direction of the pumping tail fiber successively, the upper and lower end surfaces of the laser gain medium include upper and lower heat sinks respectively, and the pumping-end cavity lens, the output cavity lens and the laser gain medium form a laser resonator. The solid state laser is characterized in that the laser gain medium is a periodic composite gain medium which is formed by slice-shaped laser crystals in the micron level thickness and slice high-thermal-conductivity materials in the in the micron level thickness by high-temperature bonding. The solid state laser can realize laser output of high power, high beam quality and high polarization degree.

The invention discloses a periodic composite material elastic constitutive parameter prediction method and device and a storage medium, and the method comprises the steps: obtaining geometric data of a target representative unit of a periodic composite material, the target representative unit being composed of a first phase material and a second phase material; based on the geometric data, a double-layer voxelization grid model corresponding to the target representative unit is established, and the double-layer voxelization grid model comprises a coarse grid model and a fine grid model; determining a boundary voxel corresponding to the junction of the first phase material and the second phase material in the coarse mesh model according to the respective spatial ranges of the first phase material and the second phase material in the target representative unit; reconstructing boundary voxels in the coarse mesh model according to the fine mesh model; and performing finite element analysis on the new coarse mesh model obtained after subdivision to obtain the elastic constitutive parameters of the periodic composite material. The technical problem of low prediction efficiency of the elastic constitutive parameters of the periodic composite material in the prior art is solved.

The invention discloses a simple implementation method for predicting the periodical composite material thermal conductivity coefficient in a gradual and homogeneous manner. A unit cell finite element model is established through commercial finite element software; the material thermal conductivity coefficient of the unit cell finite element model is set; the unit cell finite element model is subjected to finite element mesh dividing to obtain node and unit information of the unit cell finite element model; an initial temperature field is determined according to node coordinate values of the unit cell finite element model; and the periodical composite material thermal conductivity coefficient is calculated. According to the simple implementation method, the performance predication for any complex periodical structure can be realized by the unit type and any combination provided by the commercial finite element software; an integration operation is required for each unit when a right end load of a temperature gradient field control equation is solved by the original homogenization method; the original homogenization method, different from a conventional finite element format, can be realized by requiring corresponding programming, so that the original homogenization method is relatively high in threshold in use; however, the simple implementation method provided by the invention enables the homogenization method to perform direct calculation through the existing commercial finite element software, so that the difficulty in use is greatly lowered.

The invention provides a spot-laid periodic cushion vibration-reducing track bed, which includes a periodic compound track bed slab and a concrete base arranged below it, and the space between the periodic compound track bed slab and the concrete base is limited by a limiting structure to prevent Relative displacement, wherein, the periodic composite track bed slab is formed by alternately arranging and consolidating concrete slabs and periodic cushions from top to bottom, and the projections of the concrete slabs in the vertical direction are completely coincident; each concrete slab is adjacent to its lower The periodic cushion layer constitutes a basic unit, and the number of periodic repetitions of the basic unit along the vertical direction is not less than 2; the periodic cushion layer is discretely distributed according to the law along the driving direction by a square cushion plate. The vibration-damping ballast bed forms elastic wave forbidden bands in the vertical direction, transverse direction and longitudinal direction, which can effectively control the propagation of vibration in three directions, and can actively adjust the forbidden band range by changing the structural geometric size and material composition, and has strong adjustability.

The invention provides a soft-hard composite nanometer multi-coating cutter and a preparation method thereof. The soft-hard composite nanometer multi-coating cutter is characterized in that a matrix material is hard alloy, and the coatings include a Zr transition layer, a (ZrN-CrCN)x periodic composite multilayer nano hard coating and a WS2 soft coating in sequence from bottom to top. In preparation of the coatings, only N2 is adopted as reaction gas, the other coating elements are solid targets respectively, so that the pollution in deposition of different coatings is effectively prevented. The WS2 soft coating has extremely-low shearing strength and friction coefficient, the (ZrN-CrCN)x periodic composite multilayer nano hard coating has extremely-high wear resistance, and as a transition layer, Zr is used for reducing residual heat stress between the coatings and the matrix, so that the bonding force between the coatings and the matrix is improved; the wear resistance of the cutteris greatly improved, and the cutting force and the cutting temperature of the cutter in cutting are reduced, so that the cutter can better adapt to severe cutting environment in cutting.

The invention belongs to the technical field of surface treatment of low temperature plasma materials, and particularly relates to a method for preventing seizure of Ti alloy workpieces. The method comprises nine steps. The method realizes a preparation process of Ti-TiN periodic composite coating by Ti alloy workpiece baking degassing, ion beam sputtering cleaning and in-situ ion beam assisted magnetron sputtering deposition to obtain the uniform and compact Ti-TiN periodic composite coating with good bonding performance. The method has the advantage of improving the characteristics such as the wear resistance, fatigue resistance and fretting wear of the workpieces to meet the requirements of anti-seizure and wear resistance. The Ti-TiN periodic composite coating prepared on an inner threaded surface of a Ti alloy fastener has the advantages of high purity, good film-based bonding performance, uniform and dense film layers, and no porosity at the interface. The treated Ti alloy fastener meets the requirements of wear resistance, anti-seizure, anti-fretting wear and the like, has at least 2 times higher anti-seizure performance than untreated workpieces, meets the use requirementsof a certain type of equipment, greatly reduces the cost, and improves the overall use stability and the service life of the equipment.

The invention discloses a flexible ablation resistor thin film and a preparation method thereof. The flexible ablation resistor thin film comprises a flexible substrate and an ablation resistor thin film, wherein a composite transition layer is arranged therebetween, and the composite transition layer comprises a periodic composite film formed by alternately depositing Si3N4 layers, AlN layers andAl2O3 layers. The preparation method comprises the steps of preparing the composite transition layer and preparing the ablation resistor thin film. The flexible ablation resistor thin film has the advantages of high environmental interference resistance, high reliability level and the like. The preparation method of the flexible ablation resistor thin film has the advantages of simple preparationprocess, high environmental adaptability, good reliability and the like. The flexible ablation resistor thin film can be used in a heatproof protection layer of spacecrafts such as a hypersonic aircraft, a solid rocket engine and the like, can realize ablation volume measurement in harsh environments such as high temperature and high heat flow scouring, and is of great significance to improving the application reliability of spacecrafts such as a hypersonic aircraft, a solid rocket engine and the like.

A solid state laser comprises a pumping source, a pumping tail fiber, and a first coupling lens, a second coupling lens, a pumping-end cavity lens, a laser gain medium and an output cavity lens arranged in the pumping laser output direction of the pumping tail fiber successively, the upper and lower end surfaces of the laser gain medium include upper and lower heat sinks respectively, and the pumping-end cavity lens, the output cavity lens and the laser gain medium form a laser resonator. The solid state laser is characterized in that the laser gain medium is a periodic composite gain medium which is formed by slice-shaped laser crystals in the micron level thickness and slice high-thermal-conductivity materials in the in the micron level thickness by high-temperature bonding. The solid state laser can realize laser output of high power, high beam quality and high polarization degree.

The invention relates to a novel phonon crystal deceleration pavement structure. The novel phonon crystal deceleration pavement structure is formed by sequentially overlapping five base plates and four phonon crystal thin plates, wherein the base plates are solid rubber plates, and vehicles can stably run on the base plates, the phonon crystal thin plates are rubber plates, and cylindrical small holes are regularly distributed to serve as scatterers so as to form a periodic distribution energy band structure of elastic constants and density. The base plates and the phonon crystal thin plates are sequentially overlaid to form the composite elastic wave phonon crystal structure with periodically modulated body elastic modulus and mass density. Compared with the prior art, a three-dimensional photon crystal periodic composite structure is adopted, and energy dissipation and speed reduction effects on vehicles can be achieved based on periodic Bragg scattering and local monomer Mie scattering.

The invention relates to a preparation method of a micro-lens array. The preparation method comprises the following steps: preparing a blank plate: the blank is prepared into the blank plate with theperiodic composite structure through rod-pipe combination, wire drawing, plate arrangement and melt pressure; and ion beam etching: the surface of the blank plate is etched by ion beams. The inventionalso provides the micro-lens array prepared by the method. The photoresist is not used so as to avoid the process of photoetching and hot melting, and the obtained micro-lens array is made of glass material and has better optical performance and physicochemical stability.

A semiconductor device with a narrow line width and a manufacturing method thereof, wherein the semiconductor device with a narrow line width includes: a substrate layer; a gain structure located on the substrate layer; a part of the gain structure located on the side facing away from the substrate layer The line width modulation layer; the line width modulation layer includes: a transmission unit, the transmission unit includes a first periodic composite film, and a second period located on the surface of the first periodic composite film facing away from the gain structure Composite film; a defect layer located on the side of the transmission unit facing away from the gain structure; a third period composite film located on the side of the defect layer facing away from the gain structure; the second period composite film, defect layer and the third periodic composite film form a resonant cavity. The line width of light emitted by the semiconductor device with narrow line width is effectively narrowed, and the structure is simple and the integration degree is high.

The embodiment of the invention provides an ultraviolet light-emitting diode epitaxial structure, an ultraviolet light-emitting diode and electronic equipment. The epitaxial structure comprises a substrate, a first AlN layer, a multi-cycle composite regulation and control layer, an n-type Al < x > Ga < 1-x > N contact layer, a multi-quantum well light-emitting layer, a p-type Al < y > Ga < 1-y > N barrier layer and a p-type GaN layer which are sequentially grown from bottom to top, and the multi-cycle composite regulation and control layer comprises a plurality of cycle structures which are sequentially grown from bottom to top, each periodic structure comprises a second AlN layer, an Al < m > Ga < 1-m > N layer, an Al < n > Ga < 1-n > N layer and an Al < k > Ga < 1-k > N layer which are sequentially grown from bottom to top, and Al components in the n-type Al < x > Ga < 1-x > N contact layer, the Al < m > Ga < 1-m > N layer, the Al < n > Ga < 1-n > N layer and the Al < k > Ga < 1-k > N layer are different. According to the ultraviolet light-emitting diode epitaxial wafer, the multi-cycle composite regulation and control layer is grown between the first AlN layer and the n-type AlxGa1-xN contact layer, so that lattice mismatch between the first AlN layer and the n-type AlxGa1-xN contact layer is reduced, warping of the ultraviolet light-emitting diode epitaxial wafer is regulated and controlled, dislocation of upward extension of the first AlN layer is filtered, pressure stress of the n-type AlxGa1-xN contact layer is reduced, crystal quality is improved, and light-emitting efficiency of a device is improved.

The invention discloses a cutting tool composite coating, the functional layer of which comprises: a TiAlN single layer, a TiAlN / TiSiN nanocomposite layer, a TiSiN single layer and a TiAlN / TiSiN nanocomposite layer, and TiAlN is sequentially deposited on the surface of the TiAlN single layer / TiSiN nanocomposite layer, TiSiN single layer and TiAlN / TiSiN nanocomposite layer, described functional layer is the composite coating that contains multiple cycles; A kind of cutting tool composite coating and preparation method thereof provided by the present invention, cutting tool The composite coating has a periodic composite structure, which makes it have a good film-base adhesion effect under the premise of high hardness. It can be used to process die steel, high-speed steel, high-temperature alloy steel and even hardened steel.

The invention relates to the technical field of semiconductor photoetching, and particularly relates to a patterned sapphire substrate, a preparation method thereof and an LED epitaxial wafer. The patterned sapphire substrate comprises a substrate body and a periodic composite structure protruding out of the upper surface of the substrate body. The composite structure comprises a cone and a plurality of microstructures protruding out of or recessed into the conical surface of the cone. The cross sectional area of the microstructure is gradually reduced from the bottom to the top, and the microstructure intersects with the vertex of the cone at the top. The patterned sapphire substrate is provided with regular gully patterns and edges and corners, on one hand, side growth is maximized, mismatch dislocation of epitaxial growth is effectively restrained, on the other hand, the light path of incident light is further changed, light scattering is effectively increased, the emergent probability of the light from the sapphire substrate is increased, and the light extraction efficiency is further improved.