213results about How to "Solve the brittleness problem" patented technology

The invention discloses a halogen-free high heat-resistant and heat-conducting resin film and a manufacturing method thereof. The halogen-free high heat-resistant and heat-conducting resin film is prepared by semi-curing of a heat-conducting resin liquid, wherein the heat-conducting resin liquid is prepared from 70 to 100 parts of a halogen-free epoxy resin, 0 to 30 parts of one or more flexibilizers, 80 to 120 parts of one or more solvents, 1 to 20 parts of one or more curing agents, 0.01 to 1 part of one or more promoters, 0.5 to 5.0 parts of a coupling agent and 80 to 600 parts of one or more high heat-conducting filling materials. The halogen-free high heat-resistant and heat-conducting resin film has a thermal conductivity great than or equal to 2.5W / m.K and heat resistance (at a temperature of 300 DEG C) great than or equal to 300s. The halogen-free high heat-resistant and heat-conducting resin film has flexibility so that the problem of brittleness of the traditional heat-conducting materials is solved. An aluminum substrate prepared from the halogen-free high heat-resistant and heat-conducting resin film is suitable for electronic products such as LED, vehicle systems and variable-frequency power sources needing good heat conductivity, can greatly improve the thermal diffusivity of the electronic products, and has high reliability and energy-saving and environmental-protection effects.

The invention discloses a high-thermal-conductivity and high-pressure-resistance aluminum-based copper-clad plate which comprises copper foil, an insulated thermal conductivity adhesive layer, a binder layer and an aluminum plate, wherein the surface layer of the aluminum plate is subjected to anodic oxidation to form a ceramic protection layer, the insulated conductive adhesive layer is formed by performing high-temperature baking and semi-solidifying on a thermal conductivity adhesive solution, and the copper foil, the insulated thermal conductivity adhesive layer, the binder layer and the aluminum plate are laminated and pressed for formation in sequence. The high-thermal-conductivity and high-pressure-resistance aluminum-based copper-clad plate has the following advantages that 1, the surface adhesion force of the insulated thermal conductivity adhesive layer and the aluminum plate is increased through adding the binder layer and a coupling agent to reduce the difference influence on hot pressing caused by different expansion coefficients; 2, the oxidation resistance of the product is improved through the ceramic protection layer, and meanwhile, the bonding force of the insulated thermal conductivity adhesive layer and the aluminum plate is further enhanced; 3, the flexibility of an adhesive film is increased through adding a flexibilizer to solve the brittleness problem; 4, aluminum oxide, silicon dioxide, silicon carbide and the like are used as thermal conductive filler, so that the technical defect of poor heat dissipation performance is overcome.

The invention discloses a high-temperature-tolerance frequency selection wave-transmitting structure. The high-temperature-tolerance frequency selection wave-transmitting structure successively comprises a wave-transmitting layer, a modification bonding layer and a frequency selection layer from inside to outside, wherein the wave-transmitting layer is made of a continuous fiber reinforced ceramic-based wave-transmitting composite material; the modification bonding layer is made of a low-dielectric-constant material; the frequency selection layer is a noble metal physical plating layer or a noble metal glass conductor coating with periodic structure patterns. The high-temperature-tolerance frequency selection wave-transmitting structure can tolerate high temperature of 700 DEG C or more, and has excellent high temperature tolerance. The invention also provides a production method of the high-temperature-tolerance frequency selection wave-transmitting structure; the modification bonding layer is produced by using a plasma spraying process; the thermal damage to the substrate can be avoided, so that the substrate has high strength retention rate; the size accuracy of the frequency selection layer produced by a laser processing process can be higher than 20 microns; the frequency selection layer has high size accuracy.

The invention discloses a silicon nitride nanoribbon aerogel and a preparation method thereof, and the method comprises the following steps: 1) preparing polysiloxane sol; 2) preparing slurry; 3) constructing a three-dimensional porous carbon fiber framework formed by mutual lap joint of short-cut carbon fibers bonded by the siloxane sol; 4) curing and cracking, to be more specific, heating the three-dimensional porous carbon fiber framework to the curing temperature of the polysiloxane sol, carrying out heat preservation treatment, carrying out heating and heat preservation treatment in a nitrogen atmosphere, and cooling to the room temperature in a furnace so as to obtain a carbon fiber / silicon nitride nano fiber composite block body; and 5) decarbonizing, to be more specific, heating the carbon fiber / silicon nitride nano-fiber composite block to 400-1000 DEG C in air, and carrying out heat preservation treatment for 2-4 hours to obtain the silicon nitride nanoribbon aerogel. The silicon nitride nanoribbon aerogel prepared by the method has quite excellent high-temperature stability and thermal insulation performance, the brittleness problem of the traditional ceramic aerogel isovercome, expensive drying equipment and low-efficiency drying processes are not needed, and the silicon nitride nanoribbon aerogel is low in cost, high in efficiency and suitable for the fields of heat insulation, heat preservation, wave transmission and the like.

The invention discloses SnBiSb-series low-temperature lead-free solder and a preparation method thereof, and belongs to the technical field of low-temperature soft solder. The SnBiSb-series low-temperature lead-free solder consists of the following components in percentage by weight: 32.8-56.5% of Bi, 0.7-2.2% of Sb, the balance Sn, wherein weight percentage of Bi and Sb meets a relation b=0.006 a<2>-0.0672a+19.61+c, a is weight percentage of Bi, b is weight percentage of Sb, and c is greater than or equal to c, and smaller than or equal to 1.85. The invention further discloses a preparation method for the lead-free solder. Solder alloy of the SnBiSb-series low-temperature lead-free solder is a ternary eutectic or near-elliptic eutectic structure, is low in melting point, has excellent mechanical property and reliability, and is suitable for the low-temperature solder field.

Cold preparation technique for high chromium ferritic stainless steel seamless tube. Wherein, roll the hot-rolled formed pipe repeatedly and control the deformation value into predetermined value; take anneal for former rolling product, take out and cool with water, straighten, cut off, decrease wall, and control the deformation value into predetermined value; take empty sinking time after time to control deformation; take anneal and air cooling for finished product in vacuum. This invention solves effectively brittleness problem for ferritic stainless steel, decreases even avoids the cement out of carbide and nitride; prevents hypersensitization effectively, avoids intergranular corrosion; and the combination of cold drawing and cold rolling solves the problem that it is easy to appear flaw for ferritic stainless steel seamless tube.

The invention provides a biodegradable intravascular stent and a production method thereof. The biodegradable intravascular stent is characterized in that the biodegradable intravascular stent comprises an annular net structure made of biodegradable fiber braided threads; the annular net structure is composed of a plurality of rows of wavy structures; each row of wavy structure is composed of a plurality of V-shaped structure units; every two rows of wavy structures are parallel to each other; the endpoint in the middle of each V-shaped structure unit is connected with the endpoint in the middle of the symmetrical V-shaped structure unit in the adjacent row once every other two non-joint points to form a joint point. The biodegradable intravascular stent low in axial shortening rate can radially deform greatly due to the annular net structure, and the V-shaped structure units of two adjacent rows are connected once every other two non-joint points, so that the length of the stent is not changed greatly under the condition of great change of radial diameter of the stent, and the intravascular stent can be implanted conveniently by means of a conveyor.

The invention provides a flexible rubber emulsified asphalt cold in-place recycling mixture and a preparation method thereof. A flexible rubber emulsified asphalt cold in-place recycling mixture product is prepared by uniformly stirring emulsified asphalt, a recycled asphalt pavement material (RAP), macadam, water, cement and rubber power in a certain blending proportion. The flexible rubber emulsified asphalt cold in-place recycling mixture provided by the invention is simple and easily available in component, is green and environment-friendly by using waste rubber tires and asphalt pavementrecovered materials, and solves the problem of reuse of waste materials. Meanwhile, the mixture provided by the invention has relatively high strength and pavement performance. By adding the rubber powder, high- and low-temperature performance and fatigue performance of the emulsified asphalt cold in-place recycling mixture are improved obviously, the flexibility of a conventional emulsified asphalt cold in-place recycling mixture is improved, and the fragility problem of the conventional mixture is solved.

The invention relates to a manufacture method for copper-aluminum composite structure metal cans, belonging to metal composite structure processing technology field, which comprises an aluminum tube, an inlet copper tube and an outlet copper tube joining together. The invention adopts the steps that: firstly, the middle part of the aluminum tube is squeezed by hydraulic pressure to an enlarged drum aluminum tube, which has invariant diameter on both ends and a raised middle part; secondly, one port of the inlet copper tube and the outlet copper tube is mechanically processed into a conical surface; finally, the conical surface port of the inlet copper tube and the outlet copper tube is inserted into the taper end of the drum aluminum tube. As the conical surface port is pressured into the taper end while being electrically heated, a fixed metallic bond joint of copper-aluminum tube is formed at the contacting segment.