31results about How to "The whole is dense and uniform" patented technology

Soft foamed polyurethane plastic is produced through a one-step reaction process with isocyanate component and low-unsaturation degree polyether polyol component in the presence of water as active foaming agent, catalyst(s), foam-stabilizing surfactant, optional foaming agent, coloring agent, stuffing, fire retardant and other conventional additives and assistants. It has high tensile strength, great elongation, very high tearing strength, improved machine performance and low cost.

The invention relates to a method for improving pre-oxidation speed of polyacrylonitrile fiber through physical blending. The method comprises the following steps: performing vacuum drying on polyacrylonitrile, lignin and a plasticizer, and uniformly stirring and mixing, thus obtaining a mixed material; spinning, setting and winding to obtain a melt spun fiber, wherein a mass ratio of polyacrylonitrile to lignin to the plasticizer is (5-30):(10-30):(50-70); and performing water bath drawing on the melt spun fiber, and performing pre-oxidation to obtain the pre-oxidation polyacrylonitrile fiber. The raw material lignin is low in cost and slight in environmental pollution and is suitable for industrial production; lignin contains lots of hydroxyl groups which can achieve hydrogen-bond interaction with a polar group cyano on a polyacrylonitrile molecular chain, and lignin and polyacrylonitrile have high compatibility; moreover, the oxygen content in the lignin structure is high, the oxygen can be released in the pre-oxidation process, a uniform oxygen source is provided for an oxidation reaction of a polyacrylonitrile precursor, and a prepared pre-oxidation thread sheath-core is small in difference and dense and uniform in structure.

The invention discloses an injection forming method of a soft magnetic ferrite material.The method comprises the following steps of: 1) powder preparation: mixing and milling ferrite powder at one time, after dryness, presintering the powder, crushing the presintered powder for secondary mixing and milling, and performing drying treatment, 2) mixing and granulation: uniformly mixing the powder obtained in Step 1) with an adhesive, mixing to form a mixture, crushing the mixture, 3) injection forming: heating the crushed mixture, injecting into a mold cavity under a pressure condition, opening a mold for cooling, then obtaining a forming body, 4) degreasing: putting the forming body in trichloro ethylene for degreasing, drying, and then performing heat degreasing, and 5) sintering: sintering the degreased forming body to form the soft magnetic ferrite material.The method is suitable for preparing middle and small high-precision ferrite core devices in complicated shapes, and the prepared soft magnetic ferrite material has the characteristics of large and uniform density, uniform internal structure, high mechanical strength and relatively low iron loss.

The invention discloses a tool for compacting a thick-walled hollow carbon/carbon (C/C) composite product, which comprises an outer barrel, a gas inlet substrate and a gas guide device, wherein the interior of the outer barrel is provided with a gas inlet basal plate; a cavity I is formed between the gas inlet substrate and the gas inlet basal plate; the gas inlet substrate is provided with a gas inlet; the top face of the gas inlet basal plate is provided with an inner barrel; a to-be-compacted thick-walled hollow C/C composite preform is sheathed onto the inner barrel; a gap I for the circulation of gas is formed between the outer surface of the C/C composite preform and the inner surface of the outer barrel; a gap II for the circulation of the gas is formed between the inner surface of the C/C composite preform and the outer surface of the inner barrel; and the gas inlet basal plate is provided with a plurality of diversion passages II and diversion passages III, wherein the diversion passages II are used for communicating the cavity I with the gap I, and the diversion passages III are used for communicating the cavity I and the gap II. According to the tool for compacting the thick-walled hollow C/C composite product, gas diversion can be performed, and thereby, the retention period of pyrolysis gas in a depositing space is shortened, and the C/C composite preform is rapidly and evenly compacted.

The invention discloses a spray deposition densifying device and the application thereof. The device disclosed by the invention includes a rotating shaft, wherein a plurality of rotating balls are fixed on the rotating shaft; each rotating ball is fixed on the rotating shaft through a flexible chain; during the rotation of the rotating shaft, the rotating balls are distributed in a spiral line around the rotating shaft, the extending direction of the spiral line is the same as the axial direction of the rotating shaft, and the length of the flexible chain in the direction the same as the rotating direction of the rotating shaft periodically changes along the spiral line; within each period, the length of the flexible chain is gradually increased in the direction the same as the rotating direction of the rotating shaft; the screw pitch of the spiral line is 30-50 mm; and the central angle of ball centers of the two adjacent rotating balls is 10-15 degrees. During the spray deposition, the rotating balls in the densifying device are used for impacting the surface of a deposition blank, metallurgical bonding is generated under the shearing action, the deposition blank is densified layer by layer through the rotation of a pipe blank during the spray deposition, the entire densification is realized in an accumulated manner, so that the pipe stock with high performance is obtained.

The invention relates to the technical field of aluminum alloy powder materials for 3D printing, in particular to high-toughness AlCrSc alloy powder for 3D printing and a preparation method and an application thereof. The aluminum alloy powder material for the 3D printing provided by the invention comprises the following alloy elements: 1.0 to 4.0 weight percent of Cr, 0.3 to 1.1 weight percent of Sc, 0.1 to 0.6 weight percent of Zr, 0.5 to 1.2 weight percent of Si, 0.1 to 0.7 weight percent of Mn, 0 to 6.0 weight percent of Mg, less than 0.1 weight percent of trace elements and the balance of Al; and the trace elements are one or more of Ti, Fe, Ni, Ce, Sr, Er and La. Research shows that according to the aluminum alloy powder obtained by controlling the conditions, a printed part formed by the 3D printing technology is high in density, strength and plasticity and good in corrosion resistance, yield ratio and fatigue performance, meanwhile, the problems of smoke dust and oxidation in the printing process are solved, and therefore the oxidation resistance and the fatigue resistance of the printed part are improved. The 3D printed part obtained through the method has great potential prospects in engineering application such as force bearing parts, light-weight integrated parts and heat exchangers and radiators.

The invention discloses a modified silanized metal surface pretreatment agent containing diphenylethyl diphenol polyoxyethylene ether. The pretreatment agent is prepared from the following raw materials in parts by weight: 100 parts of deionized water, 10-15 parts of modified coupling agent, 10-15 parts of ethanol, 30-40 parts of gamma-chloropropyl triethoxysilane, 20-30 parts of gamma-glycidyloxypropyl trimethoxysilane, 1-2 parts of dicumyl peroxide, 0.002-0.003 part of perfluorooctyl sodium sulfonate, 0.3-0.5 part of wood ash, 4-6 parts of acrylic emulsion, 2-3 parts of sodium carboxymethyl cellulose, 0.4-1.0 part of Span80, 0.2-0.6 part of diphenylethyl diphenol polyoxyethylene ether, 0.005-0.01 part of lanthanum acetate and 0.1-0.3 part of phytic acid. A final product is obtained by modifying the coupling agent, compounding, adding auxiliaries and carrying out distribution, mixing and reaction. The modified silanized surface pretreatment agent has the characteristics of no toxicity, environment friendliness, convenience in use, compact and uniform silane film, strong adhesion and good corrosion resistance.

The invention discloses a silane treating agent and a preparation method thereof. The silane treating agent comprises, by weight, 2-5 parts of a silane coupling agent, 2-5 parts of phytic acid, 8-14 parts of nitrate, 4-7 parts of molybdate and 70-100 parts of water. The silane treating agent prepared through the method has the beneficial effects of being stable in performance and free of poison and pollution. After the silane treating agent prepared through the method is utilized for treating a metal workpiece, a film layer formed on the metal surface has the beneficial effects of being excellent in adhesive force, compact, uniform and low in polarization current density. The defects of existing metal surface pretreatment are overcome, and therefore the silane treating agent can be applied to metal surface pretreatment better.

The invention discloses a modified silanized metal surface pretreatment agent containing polyoxyethylene sorbitan monooleate. The pretreatment agent is prepared from the following raw materials in parts by weight: 100 parts of deionized water, 10-15 parts of modified coupling agent, 10-15 parts of propylene glycol, 30-40 parts of silane coupling agent KH-42, 20-30 parts of silane coupling agent KH-151, 1-2 parts of dicumyl peroxide, 0.002-0.003 part of perfluorooctyl sodium sulfonate, 0.3-0.5 part of wood ash, 4-6 parts of water-borne epoxy resin emulsion, 2-3 parts of sodium carboxymethyl cellulose, 0.4-1.0 part of polyoxyethylene sorbitan monooleate, 0.2-0.6 part of phenylethyl diphenol polyoxyethylene ether, 0.005-0.01 part of lanthanum acetate and 0.1-0.3 part of phytic acid. A final product is obtained by modifying the coupling agent, compounding, adding auxiliaries and carrying out distribution, mixing and reaction. The modified silanized surface pretreatment agent has the characteristics of no toxicity, environment friendliness, convenience in use, compact and uniform silane film, strong adhesion and good corrosion resistance.

The invention discloses a light-emitting diode gold electrode preparation method, which comprises the following steps: firstly, an ohmic-contact metal layer and a thin gold layer undergo vapour-deposition successively, and then the chemical reduction gold plating is adopted to precipitate a gold layer with a required thickness on the surface of the thin gold layer undergoing the vapour-deposition, so that the preparation of the light-emitting diode gold electrode is completed. The method adopts the chemical reduction gold plating method to prepare the gold electrode, so as to save significantly the consumption of gold, and lower the cost of raw material. The preparation method is simple in operation, and the storage of plating solution is stable. The prepared gold electrode has the advantages of high purity, smooth and bright surface, compactness and uniformity, has no pin-hole cracks or other defects, and is firmly combined.

The invention relates to down jacket manufacturing, in particular to a manufacturing method and special tool which are high in processing efficiency and quality and beneficial for producing double-row down jacket ornament folds in batches. The method includes the following steps of placing pleated fabric and down jacket surface fabric on an operation console of a double-needle machine in an overlapping mode, adjusting a bobbin case, a thread clamping device and the stitch length of the double-needle machine, rotating a screw shaft on a presser foot of the double-needle machine so that an included angle ranging from 20 degrees to 30 degrees can be formed between a bottom plate and the operation console, and finally conducting thread conveying. The presser foot used for achieving the method comprises the base and an installation part, wherein two grooves for needles to penetrate through are formed in the bottom plate, an adjustment part is arranged between the bottom plate and the installation part, and the adjustment part comprises the screw shaft, a spring and a pressing ord. Operation is easy, the garment quality is ensured, and the production efficiency is improved.

The invention discloses a modified silanized metal surface pretreatment agent containing fatty alcohol-polyoxyethylene ether. The pretreatment agent is prepared from the following raw materials in parts by weight: 100 parts of deionized water, 10-15 parts of modified coupling agent, 10-15 parts of propyl alcohol, 30-40 parts of gamma-chloropropyl triethoxysilane, 20-30 parts of gamma-chloropropyl methyldimethoxysilane, 1-2 parts of dicumyl peroxide, 0.002-0.003 part of perfluorooctyl sodium sulfonate, 0.3-0.5 part of dioctyldilauryltin, 4-6 parts of epoxy resin emulsion, 2-3 parts of sodium carboxymethyl cellulose, 0.4-1.0 part of Span80, 0.2-0.6 part of fatty alcohol-polyoxyethylene ether, 0.005-0.01 part of lanthanum acetate and 0.1-0.3 part of phytic acid. A final product is obtained by modifying the coupling agent, compounding, adding auxiliaries and carrying out distribution, mixing and reaction. The modified silanized surface pretreatment agent has the characteristics of no toxicity, environment friendliness, convenience in use, compact and uniform silane film, strong adhesion and good corrosion resistance.

The invention relates to a palladium alloy which comprises the following components in percentage by mass: 20-25% of tungsten, 40-50% of palladium, 20-30% of tin and 5-10% of chromium. The hardness of the palladium alloy is 500-550Hv, the tensile strength is up to 1600-1700 MPa, the elongation percentage is 10-15%, the Young's modulus is 140-160 GPa, and the resistivity is 200-280 mu ohm.cm.

The invention relates to granules of a microwave dielectric material for injection molding, and a manufacturing method of a microwave dielectric device. The granules comprise, by weight, 70-90% of a microwave dielectric material and 10-30% of a binder, wherein the microwave dielectric material comprises 60-70% of titanium dioxide, 25-35% of magnesium oxide, 2-8% of calcium carbonate, 2-8% of barium carbonate, 0.1-1% of niobium pentoxide, and 0.1-1% of bismuth trioxide, and the binder comprises 70-90% of polyformaldehyde, 2-15% of polymethyl methacrylate, 2-15% of polypropylene, 2-15% of an ethylene-vinyl acetate copolymer, 2-10% of wax, 1-3% of dioctyl phthalate, 1-3% of dibutyl phthalate and 1-5% of stearic acid. According to the invention, the relative dielectric constant epsilon r, theQ*f value and the resonant frequency temperature coefficient tau f of the microwave dielectric device manufactured by the method are better than those of a traditional method, and crystal grains of asample are compact, fine and uniform.