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 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 the technical field of aluminum alloy powder materials for 3D printing, in particular to a high-strength and tough AlCrSc alloy powder for 3D printing and its preparation method and application. The alloying elements of the aluminum alloy powder material for 3D printing provided by the present invention include: Cr: 1.0-4.0wt%, Sc: 0.3-1.1wt%, Zr: 0.1-0.6wt%, Si: 0.5-1.2wt%, Mn : 0.1~0.7wt%, Mg: 0~6.0wt%, trace element: <0.1wt%, the balance is Al; the trace element is one of Ti, Fe, Ni, Ce, Sr, Er, La or several. Studies have shown that the aluminum alloy powder obtained by controlling the above conditions, the printed parts formed by 3D printing technology have high density, strength, plasticity, corrosion resistance, yield strength ratio and fatigue performance, and at the same time solve the problem of the printing process. Soot and oxidation problems, thereby improving the anti-oxidation and anti-fatigue properties of printed parts. The 3D printed parts obtained by the present invention have great potential prospects in engineering applications such as load-bearing parts, lightweight integrated parts, and radiator replacements.

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.

A sealing method of the compression padding with the density gradient comprises the first step of placing the strip-shaped padding in a forming mold according to a certain weight and a certain size, the second step of pressing the strip-shaped padding into annular padding rings through a press, wherein the forming height of the padding rings can be accurately controlled through a liner stop piece with the preset height in the pressing process so that the padding rings with the required densities can be obtained, and the third step of making the padding rings overlap in the force bearing direction, wherein the densities of the padding rings sequentially increase one by one in the force bearing direction. The invention further comprises the compression padding produced according to the method, wherein the compression padding is composed of the padding rings overlapping in the force bearing direction, and the densities of the padding rings sequentially increase one by one in the force bearing direction.

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 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 relates to a zinc-iron metal alramenting liquid capable of being recycled at normal temperature. The invention is characterized in that the alramenting liquid is prepared by the following raw materials by weight percent: 14-28% of phosphoric acid, 3.5-7% of zinc oxide, 12.6-17.5% of zinc nitrate, 0.14-0.56% of citric acid, 0.14-0.7% of tartaric acid and 0.14-0.84% of molybdate, and balance of water.In the invention, phosphorization is carried out in one process after oil removing and rust removing are carried out, the processes of neutralizing, surface conditioning, passivating and washing are eliminated, and a compact and uniform phosphorization membrane with strong adhesive force is rapidly formed on the surface of ferrous metal. The process greatly reduces operation procedure, the phosphorization process produces no slag, thus reducing pollution to the environment and greatly improving utilization factor of material; and energy consumption at normal temperature is reduced and water is saved. The invention has the advantages of wide application range, less investment, high efficiency and high safety, and bath solution has good stability, no deterioration or volatilization is caused, and maintenance is easy, thus being beneficial to follow-up spraying processes.