30results about How to "Reduce interface stress" patented technology

The invention discloses a corrosion resistant fastener. Comprising a fastener base body. The surface of the fastener base body is coated with a corrosion-resistant coating; the corrosion-resistant coating comprises a transition layer, an anti-corrosion layer and a sealing layer which are sequentially stacked from inside to outside. The corrosion-resistant coating is prepared on the surface of the fastener through a vapor deposition technology and a brushing process. The anti-corrosion coating is sequentially composed of a transition layer, an anti-corrosion layer and a sealing layer, so that the problems that an existing fastener surface protection coating is low in hardness, poor in binding force, poor in friction resistance and insufficient in anti-corrosion performance are effectively solved, the anti-corrosion performance of a fastener is improved, and the service life of the fastener is prolonged.

The invention provides 1900MPa-grade cold-rolled medium manganese steel and a preparation method thereof, and relates to the technical field of high-strength and high-toughness automobile steel. The thickness of the 1900 MPa-grade cold-rolled medium manganese steel ranges from 1.3 mm to 1.5 mm, and the 1900 MPa-grade cold-rolled medium manganese steel is prepared from, by mass, 0.22%-0.25% of C, 6.5%-7.5% of Mn, 1.2%-1.7% of Al, 0.7%-0.9% of Si and Plt. 0.005%, Slt; 0.02% of the total weight; and the balance of Fe and inevitable impurities. The preparation method comprises the steps of raw material preparation, smelting, casting, forging, hot rolling, two-phase region annealing, tempering, cold rolling, quenching and baking treatment. According to the invention, by optimizing the two-phase region annealing process and the quenching temperature, ultrafine-grained ferrite, austenite and martensite microstructures are formed, the strength of the medium manganese steel is greatly improved, the enough percentage elongation after fracture is ensured, and the performance requirements of automobile anti-collision structural components are met.

The invention relates to the technical field of additive manufacturing, in particular to an additive manufacturing low-stress high-entropy alloy design system and method based on lattice mismatch, which are used for effectively reducing interface stress of gradient materials, and the method comprises the following steps: analyzing a matrix crystal structure, and determining a high-entropy alloy crystal structure type consistent with the matrix crystal structure; based on a high-entropy alloy crystal structure, a high-entropy alloy virtual lattice approximate structure model is established; performing structure geometric optimization on the model to obtain a high-entropy alloy lattice constant under a stable structure; according to the obtained lattice constants, the proportion of all elements of the high-entropy alloy is adjusted by comparing the lattice constants of the base body, and the redesigned high-entropy alloy is calculated till the lattice mismatch degree of the high-entropy alloy and the base body is low; and gradient design is conducted on the designed high-entropy alloy with the low lattice mismatch degree and the base body, and the design result of the low lattice mismatch degree and the low interface stress of the additive manufacturing high-entropy alloy gradient material is obtained.

The preparation method comprises the following steps that an interface layer is prepared, specifically, under the vacuum condition, a carbon source and a nitrogen source are provided, and carbon-nitrogen co-permeation treatment is conducted on the surface of an elbow base body through high-energy plasma to form a carbon-nitrogen co-permeation layer serving as the interface layer; preparing a barrier layer: depositing on the surface of the carbonitriding layer through a chemical vapor deposition method to form a metal oxide layer as the barrier layer; and preparing a corrosion-resistant layer: depositing on the surface of the metal oxide layer through a chemical vapor deposition method to form a silicon carbide layer as the corrosion-resistant layer. The protective composite coating composed of the interface layer formed by the carbon-nitrogen co-permeation layer, the barrier layer formed by the metal oxide layer and the corrosion-resistant layer is combined to the surface of the elbow base body, so that the metal elbow has the low average erosion rate and average wear rate, and the safety and reliability of an oil and gas field gathering and transportation system can be remarkably improved.

The invention relates to the technical field of batteries, in particular to a composite buffer structure for a battery and a preparation method and application thereof. A composite buffer structure for a battery comprises a polymer matrix layer and a reinforcement phase located in the polymer matrix layer, the reinforcement phase comprises a shape memory alloy fiber layer, and the shape memory alloy fiber layer is of a three-dimensional network structure; and the volume fraction of the shape memory alloy fiber layer in the composite buffer structure for the battery is 10%-60%. According to the composite buffer structure for the battery, the polymer matrix layer serves as a continuous phase, the shape memory alloy fiber layer serves as a reinforcing phase, and the polymer matrix layer and the shape memory alloy fiber layer are mutually staggered in the polymer matrix layer to form a three-dimensional network structure; the shape memory alloy fiber layer with a proper volume fraction is adopted, can actively adapt to the volume change of a battery cell, shows superelasticity at the working temperature of the battery, provides high and stable recovery stress, and is excellent in fatigue resistance, so that long-term stable contact of a battery interface is effectively maintained.

The invention provides a method for preparing an ultrathin SiC / diamond composite wafer by Van der Waals force bonding. The method comprises the following steps: forming a graphene layer on one surface of a polycrystalline diamond wafer to obtain a diamond / graphene wafer; forming a graphene layer on one surface of the SiC wafer to obtain a SiC / graphene wafer; h < + > ions are injected into the SiC surface of the SiC / graphene wafer through ion injection; bonding the polycrystalline diamond and the SiC by virtue of the graphene layers of the polycrystalline diamond and the SiC through Van der Waals force bonding to obtain a bonded wafer; stripping the SiC layer of the bonded wafer at high temperature to obtain an ultrathin SiC / diamond composite wafer; and polishing the surface of the SiC layer of the ultrathin SiC / diamond composite wafer. According to the method for preparing the ultrathin SiC / diamond composite wafer through Van der Waals force bonding, low voidage and large-size bonding of diamond and silicon carbide can be achieved, the interface thermal resistance between the diamond and a device can be reduced, and the output power density of the device can be improved.

The present invention discloses a preparation method and a preparation device of a non-standard screw with a functional layer; the present invention belongs to the technical field of non-standard screws; it is a physical parameter that affects the thermal expansion characteristics of the screw and the thermal expansion characteristics of the thread modification solution, wherein the input variables include: a known and fixed thermal expansion coefficient SC of the screw, that is, the thermal expansion coefficient of the C / SiC material; the thermal expansion coefficient C of the thread modification solution on each sample i; it can be quickly calculated by a thermal expansion instrument or an exothermic method. The present invention uses a fuzzy control algorithm to accurately adjust the proportion of each component in the mixed solution, so that the thermal expansion coefficient of the thread modification solution can match the thermal expansion coefficient of the screw matrix, thereby improving the bonding strength and durability between the functional layer and the matrix. By accurately adjusting the proportion of the mixed solution by a fuzzy control algorithm, the number of adjustments can be reduced, thereby improving production efficiency, and production costs are also effectively controlled.

The application provides a hollow special-shaped skin-core structure radiation refrigeration fiber and a preparation method thereof, and belongs to the technical field of functional fiber spinning. The hollow special-shaped skin-core structure radiation refrigeration fiber comprises a skin layer and a core layer. A hollow cavity is arranged in the core layer along the fiber axial direction. The core layer is provided with a micro-foamed hole structure. The skin layer is arranged on the side peripheral surface of the core layer. The skin layer is provided with a micro-porous channel along the fiber radial direction. The skin layer is provided with a first sublayer, a second sublayer and a third sublayer along the thickness direction. The skin layer comprises a polymer and modified mesoporous nanometer silica microspheres. The core layer comprises a polymer but does not comprise modified mesoporous nanometer silica microspheres. The hollow special-shaped skin-core structure radiation refrigeration fiber realizes double thermal insulation of hollow and micro-foamed structures through the hollow special-shaped pure polymer core layer with the micro-foamed hole structure, maintains the mechanical properties of the fiber, enhances the infrared emissivity by using the high specific surface area of the mesoporous channel, simultaneously reduces the filler density, designs the three sublayers of the skin layer, and improves the functional utilization rate.

The invention relates to the technical field of preparation of graphene-polycaprolactone composite materials, in particular to a preparation method of a bionic laminated toughened graphene-polycaprolactone composite material, which comprises the following steps of: prefabricating a directional porous aerogel template, performing vacuum-assisted impregnation, performing step-by-step hot press molding and the like to establish a multi-scale bionic laminated microstructure toughening mechanism; the graphene-polycaprolactone composite material which has a nacre-like'brick (polycaprolactone)-mud (graphene) 'ordered microstructure and has high strength and high toughness is prepared, and the problems of accurate construction of a multi-scale bionic laminated structure of a low-melting-point high-brittleness organic polymer material and controllable adjustment of mechanical strengthening and toughening are solved; a new strategy is provided for strengthening and toughening preparation of organic polymers, and the method has important application value and scientific significance.

The invention discloses a dynamic stable shielding signal cable and a preparation method thereof. The cable comprises a conductor, an insulating layer wrapping the conductor and a multi-layer shielding structure wrapping the insulating layer. The multi-layer shielding structure comprises an inner shielding layer and a composite shielding layer; the composite shielding layer is a multi-layer composite belt and comprises a metal conductive layer and at least two polymer bonding layers; a melt blending interface is arranged between the inner shielding layer and the composite shielding layer, and the melt blending interface is formed by combining the polymer bonding layer located in the inner side area with the back face of the inner shielding layer in a molten state and solidifying the polymer bonding layer and the back face of the inner shielding layer. According to the invention, the multiple shielding layers form an integrated structure with cooperative deformation, so that the shielding effectiveness maintaining capability of the cable under a dynamic bending working condition is remarkably improved.

This invention belongs to the field of metal coating technology, specifically relating to a gradient composite coating, its preparation method, and its application. The composite coating of this invention comprises a multilayer Al3BC / Al composite material coating, wherein the Al3BC content in the Al3BC / Al composite material is 0 wt.% to 80 wt.%, and the Al3BC content increases or decreases sequentially from the inside to the outside of the multilayer coating, wherein the multilayer comprises at least three layers. The gradient Al3BC / Al composite coating of this invention balances high reflectivity, ablation resistance, lateral heat dissipation, longitudinal heat insulation, and low internal stress in laser protection scenarios, as well as high surface hardness, low interfacial stress, and high bonding strength in wear-resistant scenarios. Furthermore, the preparation method of the gradient Al3BC / Al composite coating is simple, with controllable parameters, and suitable for mass production. This invention also provides applications of this coating in the fields of laser protection coatings and wear-resistant coatings.

The invention discloses a preparation method of a ZnO window layer film with Mo as a buffer layer, and belongs to the technical field of film preparation. The method sequentially comprises the steps of substrate pretreatment, Mo buffer layer magnetron sputtering deposition, ZnO window layer radio frequency magnetron sputtering deposition and annealing post-treatment. Through precise regulation and control of process parameters, lattice transition matching is realized by means of characteristics of Mo and ZnO. The method effectively solves the problems of weak binding force between the ZnO film and the substrate, poor crystallization quality, high defect density, high energy consumption and the like in the prior art, is high in process compatibility and controllable in parameter, is suitable for large-scale preparation of the high-performance ZnO film, and can be widely applied to the photoelectron fields of solar cells, display devices and the like.

This invention discloses a multi-structured coating, its preparation method, and its application. The coating comprises a TiAlN substrate, an AlTiN gradient layer with increasing Al content, an AlTiN / TiSiN nanolayer, and a TiSiN nanocomposite layer, sequentially connected. The substrate is connected to the substrate. The AlTiN gradient layer with increasing Al content is immediately connected to the TiAlN substrate. The AlTiN / TiSiN nanolayer is a nano-multilayer structure composed of alternating AlTiN and TiSiN layers. The TiSiN layer is a nanocomposite structure composed of nanocrystalline embedded amorphous substrate. The total thickness of the coating is controlled between 1.0 and 6.0 μm. The multi-structured coating exhibits a bonding strength of 65–120 N with the substrate, a nanohardness of 32–35 GPa, and a fracture toughness of 5.9–10 MPa·m. 1 / 2 It has strong toughness and corrosion resistance, and high bonding strength. Its coated tools have a cutting life that is much longer than that of traditional AlTiN coated tools.

The invention provides a drill rod and a preparation method thereof. The drill rod comprises a drill rod pipe body, a carburizing-silicon-nitrogen layer, a corrosion-resistant layer, a female connector and a male connector, the carburizing-silicon-nitrogen layer and the corrosion-resistant layer are sequentially arranged on the surface of the drill rod pipe body, the female connector and the male connector are connected with the drill rod pipe body, the corrosion-resistant layer comprises a nanometer titanium nitride layer, and nanometer titanium nitride is arranged on the surface, away from the drill rod pipe body, of the carburizing-silicon-nitrogen layer; and the nano titanium carbide layer is arranged on the surface, away from the carburizing-silicon-nitrogen layer, of the nano titanium carbide layer. The composite structure layer formed by the carburized-silicon-nitrogen layer, the nano titanium nitride layer and the nano titanium carbide layer has the excellent characteristics of high hardness, strong combination, low abrasion, high corrosion resistance and the like, the surface hardness of the drill rod can be remarkably improved, the abrasion rate of the drill rod is reduced, and then the abrasion resistance and corrosion resistance of the drill rod are improved.

The invention discloses a composite proton exchange membrane based on large-area single-layer nano-porous graphene Nafion and a preparation method of the composite proton exchange membrane. The preparation method comprises the following steps: firstly, performing plasma etching to obtain a graphene / copper foil sample; spin-coating Nafion latex on the graphene surface of the graphene / copper foil sample; the spin-coated graphene / copper foil sample is dried and cured, a Nafion film is hot-pressed on the spin-coated surface of the graphene sample, and a Nafion / graphene / copper foil sample is obtained; the method comprises the following steps: etching a Nafion / graphene / copper foil sample in an etching solution, then washing the sample, and completing etching, cleaning and airing of the residual copper foil; the Nafion latex is continuously spin-coated; the spin-coated Nafion / graphene sample is dried and cured, and then the spin-coated Nafion / graphene sample and a Nafion thin film are subjected to hot-pressing compounding; and soaking the Nafion / graphene / Nafion sample in an acid solution, and airing to obtain the proton exchange membrane based on the large-area single-layer nano-porous graphene Nafion composite. According to the invention, the bottleneck of performance improvement caused by insufficient selectivity of the proton exchange membrane and low proton transmission efficiency of the intrinsic graphene is effectively solved.

The application provides a low-resistance high-temperature-resistant conductive adhesive as well as a preparation method, a use method and a photovoltaic module thereof, and relates to the technical field of electronic packaging materials. The low-resistance high-temperature-resistant conductive adhesive comprises, calculated based on the total mass of raw materials of the low-resistance high-temperature-resistant conductive adhesive as 100%, 45-60% of silver-coated ceramic powder, 10-20% of nano silver wire, 1-2% of silicon carbide whisker, 20-30% of polyimide resin and 0.1-0.5% of antioxidant. The base material of the polyimide resin is acetylene-terminated polyimide. The antioxidant comprises BHT. The conductive adhesive provided by the application can enable the material to maintain stable conductive performance and mechanical strength after long-term high-temperature aging, and is suitable for application scenarios such as photovoltaic modules which have strict requirements on weather resistance.

The invention discloses a high-air-tightness COB light source structure which comprises a substrate, a circle of box dam rubber ring is arranged on the upper surface of the substrate, a die bonding groove is defined by the box dam rubber ring, a plurality of LED chips are arranged in the die bonding groove of the substrate, and the die bonding groove of the substrate is filled with fluorescent powder glue so that the LED chips can be wrapped by the fluorescent powder glue. The upper surface of the fluorescent powder glue is covered with an isolation glue layer, the joint between the isolation glue layer and the box dam rubber ring is provided with a circle of covering rubber ring, and the manufacturing method comprises the following steps: arranging a plurality of LED chips in a light source area on the upper surface of the substrate; a circle of box dam rubber ring surrounding the light source area is arranged on the upper surface of the substrate, and heating and pre-curing are conducted; the solid crystal groove is filled with fluorescent powder glue, and heating and pre-curing are carried out; spraying isolation glue on the upper surface of the fluorescent powder glue and the top of the box dam rubber ring, heating and curing to form an isolation glue layer, and enabling the isolation glue layer to cover the whole upper surface of the fluorescent powder glue and the top of the box dam rubber ring; and a covering rubber ring is arranged at a connecting gap between the isolation rubber layer and the box dam rubber ring, and heating and pre-curing are carried out.

The application discloses a forming method of a composite material flange and a die thereof in the technical field of aviation structure connecting piece manufacturing, and comprises die pretreatment, layered paving design, twisted filament core material preparation and soft die auxiliary forming. The fiber arrangement is optimized by arranging the R area gradient paving and the flexible gasket in a spaced mode, and the structure stability is ensured by combining the tooth groove locking edge packaging. A step type heat sealing and pressing curing process is adopted, and the R area and the plane area are synchronously compacted by cooperating with the air bag pressurization. The process covers core material filling verification, vacuum pre-pressing and temperature control demolding, and finally a high-precision flange component is obtained. Through the synergistic process of the gradual pre-compaction and the step type heat sealing and pressing curing, the application effectively solves the problems of poor fiber adhesion, uneven pressure and stress concentration of the R area of the composite material flange, realizes the continuous arrangement of the fiber of the complex curved surface, significantly reduces the internal stress of the interface, and finally obtains a high-quality flange component with a compact structure and uniform performance.

The present invention relates to a semiconductor structure and a method for forming the same. The semiconductor structure comprises: a substrate and a dielectric layer, wherein the substrate has a front side and a back side arranged opposite to each other, and the dielectric layer is formed on the front side; a connecting hole, which penetrates the substrate and extends to the dielectric layer; an insulating layer, which is located on the inner wall surface of the connecting hole; and a connecting structure, which comprises a first barrier layer, a second barrier layer and a conductive structure, wherein the first barrier layer is located on the surface of the insulating layer, and the second barrier layer is located between the first barrier layer and the conductive structure, and has an air gap between the first barrier layer and the second barrier layer. The present application can effectively prevent the barrier layer from breaking.

This invention belongs to the field of thermal spraying preparation technology, specifically relating to a Ti-containing spraying powder and its preparation method. The preparation method of the Ti-containing spraying powder provided by this invention includes the following steps: mixing TiC powder and WC powder to obtain a mixture; subjecting the mixture to high-temperature chemical treatment, then ball milling and sieving to obtain a chemically treated powder; mixing the chemically treated powder, nickel powder, cobalt powder, a forming agent, and water, and then wet ball milling; spray-drying the ball-milled slurry and sieving to obtain a spray-dried material; and sintering the spray-dried material to obtain the Ti-containing spraying powder. The Ti-containing spraying powder provided by this invention can effectively reduce internal defects in the coating, achieve low porosity and high density, effectively improve the wear resistance of the coating, and also possess excellent bonding strength.

The invention provides an adhesive composition, a wafer-level packaging structure, a preparation method of the wafer-level packaging structure and a semiconductor device. The adhesive composition of the present invention comprises (A) an alicyclic epoxy compound; (B) a cationic initiator; (C) a cationic stabilizer; and (D) a nanofiller. The adhesive composition disclosed by the invention has low curing shrinkage rate and good thixotropic property, adverse effects of an adhesive overflow phenomenon on the appearance and performance of a product can be avoided in a construction process, and the obtained cured resin has the advantages of small volume shrinkage rate, good chemical resistance, good normal-temperature storage performance and the like.

The invention relates to the field of biomedical materials, and particularly discloses a method for improving the bonding strength of a tantalum coating on the surface of a biomedical peek material. According to the method, a magnetron sputtering method is adopted, a titanium target and a tantalum target serve as target materials, a Ti layer is firstly deposited on the surface of a peek material to serve as a transition layer, then a Ta layer and a Ti layer are alternately deposited on the surface of the transition layer, a functional coating is formed on the surface of the transition layer, the finally formed material structure is peek-Ti-(Ta-Ti) n-Ta, in the formula, n is 1-3, and the bonding strength of the coating is 40-60 MPa. According to the method, the Ti transition layer and the Ta-Ti alternate coating are constructed on the surface of the peek material, so that the stress of the coating is reduced, and the bonding strength, stability and durability between the peek material and the coating are improved.

The invention relates to the field of functional materials, and discloses a wear-resistant anti-corrosion material and a preparation method thereof, a wear-resistant anti-corrosion plunger rod and a preparation method and application of the wear-resistant anti-corrosion plunger rod. Wherein the wear-resistant anti-corrosion coating sequentially comprises a Si interface layer, a nano TiCN layer and a nano SiC layer from the inner interface of the coating to the outer surface of the coating. The wear-resistant and corrosion-resistant material and the wear-resistant and corrosion-resistant plunger rod provided by the invention have excellent wear resistance and corrosion resistance.

This invention relates to the field of semiconductor technology, and particularly to a heterogeneous thin-film substrate and its preparation method. The preparation method includes the following steps: obtaining a heterogeneous thin-film substrate to be annealed, the heterogeneous thin-film substrate comprising a substrate and a first thin film formed on one side surface of the substrate; forming a second thin film on the side surface of the substrate away from the first thin film, obtaining a composite substrate; the coefficient of thermal expansion of the second thin film is α1, the coefficient of thermal expansion of the substrate is α2, and the coefficient of thermal expansion of the first thin film is α3, satisfying the following condition: α1 < α2 < α3 or α1 > α2 > α3; and performing high-temperature annealing on the composite substrate to obtain the heterogeneous thin-film substrate. Compared with the prior art, this invention effectively alleviates the interfacial stress between the first thin film and the substrate during the annealing process of the heterogeneous substrate, prevents functional film cracking and substrate fragmentation, and improves the product yield of the heterogeneous thin-film substrate.

The method comprises the following steps: 1, dissolving zinc nitrate hexahydrate and hexamethylenetetramine in deionized water, carrying out a hydrothermal reaction, carrying out centrifugal separation on a precipitate, and carrying out heat treatment to obtain single crystal ZnO nano-particle powder; and 2, adding the single crystal ZnO nano particle powder and butyl titanate into ethanol under ultrasound, mixing, adding into a water-ethanol mixed solution, reacting, centrifuging, washing, drying, carrying out heat treatment, cooling to room temperature under different processes, and annealing to obtain the phase change enhanced ZnO / TiO2 piezoelectric catalyst powder. The method for improving the activity of the zinc oxide piezoelectric electro-catalyst solves the problems that an existing method is limited in enhancement effect on ZnO, the process is complex, and the performance consistency and stability of ZnO can be reduced.

The invention provides a shield tunneling machine composite cutter ring preparation technology, and belongs to the technical field of shield tunneling machine cutter ring preparation, and the shield tunneling machine composite cutter ring preparation technology comprises the following steps: 1, preparing Fe powder and metal or nonmetal and alloy powder thereof into mixed powder, and carrying out metallurgical molding treatment to prepare a composite wear-resistant body; 2, cutting the composite wear-resistant body into small sections, and then fixing the small sections in a cavity of a casting mold; 3, the outer surface of the small-section composite wear-resisting body is coated with nano reinforced particles; fourthly, molten steel of the cutter ring base material is poured into a cavity of the casting mold, and a cutter ring blank is manufactured; 5, the cutter ring blank is machined into a finished cutter ring; the abrasion resistance of the cutter ring is improved, meanwhile, good toughness is kept, the problem that a traditional cutter ring is prone to abrasion is solved, and the overall service life of the cutter ring is prolonged. And the second-phase particles are distributed between the wear-resistant body and the steel substrate in a dispersed state to form a hardness gradient, so that the structural stability of the cutter ring is improved.

The invention relates to a novel quaternary alloy core-shell quantum dot and a preparation method thereof, CdZnSeS is adopted as a core, a ZnxCd1-xSeyS1-y transition layer is introduced, and ZnS is adopted as a shell layer, so that a quaternary alloy core-shell structure is formed. A temperature increasing growth strategy is adopted, and parameters such as the proportion, the dropwise adding sequence, the dropwise adding speed and the reaction temperature of a precursor solution are controlled, so that the prepared quantum dot not only reduces the use of a Cd element, reduces the environmental risk and the biotoxicity, but also improves the stability and the fluorescence efficiency on the premise of ensuring the high yield. The specific preparation method comprises the following steps: respectively preparing precursor solutions containing a cadmium source, a zinc source, a sulfur source, a selenium source and the like, and reacting according to a specific sequence and conditions to form a quantum dot core, a transition layer and a shell layer. In addition, by adjusting the component proportion and controlling the temperature, adjustment of the light emitting wavelength of the quantum dots and optimization of the performance are achieved, the problem that the quantum dots are unstable in practical application is solved, and wide application prospects are achieved.

The invention relates to the technical field of thin film materials, and provides a patterned high-reflection layer with good adhesion, a preparation method and an application thereof, wherein the high-reflection layer comprises an n(Si / W) layer, a gradient W-Cr alloy layer, a Cr layer, a silicon dioxide layer and a patterned reflective layer which are sequentially located on a surface-modified glass substrate from bottom to top; the n(Si / W) layer is composed of n periods of alternate deposition of Si layers and W layers, wherein the alternating period n is 30-50; the W content of the gradient W-Cr alloy layer gradually decreases and the Cr content gradually increases in a direction away from the n(Si / W) layer; the high-reflection layer of the invention realizes the combination of high reflectivity and good adhesion, solves the problems of easy peeling and poor stability of traditional high-reflection layers, and has a wide range of application value in the fields of photolithography masks, optical systems and semiconductor manufacturing, and provides a new technical path for the development of high-performance optical components.

The invention relates to a corrosion-inhibition heat-insulation gradient coating and a use method thereof. The corrosion-inhibition heat-insulation gradient coating is composed of a primer, an intermediate coat and a finish coat which are mutually independent, wherein the primer is composed of 80-90 parts of zirconium sol, 5-10 parts of hollow glass beads and 0.1-0.3 part of a dispersing agent; the intermediate paint is prepared from the following components in parts by weight: 60-70 parts of zirconium sol, 15-20 parts of hollow glass beads and 0.1-0.3 part of a dispersing agent; the finishing paint is prepared from 40 to 50 parts of zirconium sol, 25 to 30 parts of hollow glass beads and 0.1 to 0.3 part of dispersing agent. And the primer layer, the middle paint layer and the surface paint layer are sequentially coated and cured, and are finally sintered and cured. The preparation method has the beneficial effects that the ZrO-hollow glass bead coating can effectively improve the high-temperature resistance of the coating and realize corrosion resistance under extreme conditions, the thermal expansion coefficients of the coating and the substrate are matched, the generated interface stress is reduced, and the coating is prevented from being peeled off.

This invention relates to the field of pressure sensor packaging technology and discloses a micro differential pressure sensor packaging structure, including a PCB board. A MEMS chip is bonded to the inside of a mounting slot using conductive adhesive. Gold wires are mounted at one end of both the ASIC chip and the MEMS chip, with the other end of the gold wires mounted on the upper surface of the PCB board. Gold wires are also installed between the ASIC chip and the MEMS chip. A cover is mounted on the upper surface of the PCB board. A limiting structure is provided at the upper end of the substrate, and the MEMS chip is positioned in the middle of the limiting structure. This invention utilizes the fact that the thermal expansion coefficient of the substrate is between that of the MEMS chip and the PCB board, forming a gradient transition. This reduces interfacial stress caused by material expansion differences during temperature changes. The highly thermally conductive ceramic can quickly disperse the working heat of the MEMS chip, reducing the temperature gradient and avoiding piezoresistive bridge imbalance caused by local thermal deformation, thus preventing zero-point drift of the MEMS chip. Simultaneously, the high hardness and Young's modulus of the ceramic suppress the transmission of energy from PCB board bending or vibration, protecting the MEMS chip from external mechanical impacts.