46results about How to "Low shrinkage" patented technology

This invention belongs to the field of building repair materials technology and provides a water-resistant and freeze-resistant magnesium phosphate cement repair mortar and its preparation method. The raw materials of the water-resistant and freeze-resistant magnesium phosphate cement repair mortar include: modified magnesium oxide, potassium dihydrogen phosphate, admixture, retarder, fine aggregate, water-reducing agent and water. The preparation method includes: (1) dry mixing: the modified magnesium oxide, potassium dihydrogen phosphate, admixture, fine aggregate and retarder are dry mixed to obtain a dry material system; (2) wet mixing and molding: half the mass of water is added to the dry material system, and after stirring, the remaining mass of water and water-reducing agent are added, and stirring is continued to obtain the water-resistant and freeze-resistant magnesium phosphate cement repair mortar. The repair mortar has excellent water resistance, freeze resistance and mechanical properties. The preparation method has a simplified preparation process, low production cost, and can realize the high-value utilization of solid waste, meeting the needs of rapid repair of building projects in harsh environments such as dampness and cold.

The utility model provides a novel square cover structure, include: top cover piece, be provided with the installation platform on top cover piece, the installation platform is provided with the clamping portion and the bending portion who connects each other, the lower plastic, the lower plastic sets up the top cover piece directly below, be provided with the welding ring and the sealing ring of clamping in the welding ring on the lower plastic, wherein, top cover piece with lower plastic between be provided with the positive pole column and the negative pole column. The utility model provides a novel square cover structure, places the positive pole column or the negative pole column respectively in the axle center place of installation platform, pours into the supporting space to the colloid through the mould, supports the positive pole column or the negative pole column after cooling, improves the support fixed effect to the pole column through the clamping portion and the bending portion, reduces the shrinkage phenomenon of colloid flow not good to cause simultaneously, then in turn the sealing ring and the welding ring assembly to the pole column, and the outer ring of welding ring is welded, finally makes the lower plastic with top cover piece clamping, to complete the assembly to top cover assembly.

The invention discloses a processing method of a large-diameter seamless steel pipe for a nuclear power conventional island. The method comprises the following steps: preparing and smelting raw materials; a centrifugal casting step; post-processing the pipe blank; a finish machining and detection step; the centrifugal casting comprises the following steps: a casting mold pretreatment stage; a centrifugal casting stage; in the pipe blank cooling and solidifying stage, the rotary hot extrusion part is introduced into an inner cavity of the pipe blank, the outer wall of the rotary hot extrusion part is further coated with a heat insulation coating, and when the rotary hot extrusion part rotates, at least one working part on the outer wall of the rotary hot extrusion part and the inner wall of the pipe blank periodically move close to or away from each other in the radial direction; therefore, the rotary hot extrusion part can apply periodic radial compaction force to the inner wall of the pipe blank. Acting force can be directly applied to the inner wall of the hollow pipe blank in the cooling and solidification stage of the hollow pipe blank, the quality of the inner wall is fundamentally improved, and the hollow pipe blank of the high-quality large-diameter seamless steel pipe with the smooth inner wall, the compact structure and the uniform performance is produced.

The application provides a kind of polyhedral oligomeric silsesquioxane and its preparation method and application, belong to polyhedral oligomeric silsesquioxane technical field, the structural formula of polyhedral oligomeric silsesquioxane of the application is as shown in formula (1): formula (1) in, R a , R b , R c , R d , R e , R f , R g , R h At least one of them is different, and each is independently-SCH2COOCH2CH (OH) CH2OOC (CH3) =CH2, -SCH2COOCH2CH (OH) CH2O (CH2) 4Si (OCH3) 3.The polyhedral oligomeric silsesquioxane of the application is applied to adhesive or coating material, which can improve the hardness, wear resistance of adhesive or coating material, and reduce the shrinkage rate when resin curing.

This utility model relates to a crack-resistant, high thermal conductivity ceramic tile. It solves the problems of poor thermal conductivity and easy cracking and hollowing in existing ceramic tiles. It includes a ceramic tile body, with a wear-resistant and crack-resistant structural layer on the upper surface, an adhesive bonding assembly at the lower end, and a pressure-resistant mechanism in the middle layer of the ceramic tile body for connecting the wear-resistant and crack-resistant structural layer and the adhesive bonding assembly. An adhesive supply structure is provided between the pressure-resistant mechanism and the adhesive bonding assembly. The advantages of this utility model are: good thermal conductivity, less prone to cracking and hollowing, and a stable structure.

The present application relates to a kind of ultra-high purity copper smelting casting method, the smelting casting method includes: the copper material is carried out vacuum smelting, when the vacuum degree becomes 280-310 times of the vacuum degree when vacuum smelting starts in process, vacuumizing is carried out, then in turn, heat preservation and casting are carried out;The casting speed is gradient change in the casting.This smelting casting method provided by the present application realizes the preparation of ultra-high purity copper ingot by the design of vacuum degree in vacuum smelting and the combination of specific casting process, the purity of the obtained ultra-high purity copper is ≥99.9999%, and there is no inclusion and no casting defects such as internal or surface hole.

This invention belongs to the field of building materials technology, specifically relating to a silica-alumina material, its preparation method, and its application. The silica-alumina material comprises 10-65 parts by weight of red mud, 20-60 parts by weight of slag powder, 0-20 parts by weight of silicate cement clinker, 0.1-8 parts by weight of an activator, and 5-15 parts by weight of an expanding agent; wherein, based on the mass of the expanding agent, the expanding agent comprises 0-60 wt% aluminum sulfate, 0-70 wt% carbide slag, 0-70 wt% tricalcium aluminate, 0-60 wt% calcium sulfoaluminate, and 0-60 wt% gypsum, and the content of at least two components in the expanding agent is not zero. The silica-alumina material of this invention, with its specific components and contents, can achieve both high strength and low shrinkage. When used in cement mortar, it can enhance the density of the cement and prevent cracking, enabling the material to be used for a long time.

This invention relates to the field of polymer materials technology, and discloses a polypropylene foamed bead, a molded polypropylene foamed bead, its preparation method, and its application. The polypropylene foamed beads are obtained by foaming a foaming composition containing polypropylene microparticles; the average particle size of the polypropylene microparticles is ≤1 mm, the aspect ratio of the polypropylene microparticles is ≤1.2, the ash content is ≤400 ppm, and the bulk density is >0.35 g / cm³. 3 The polypropylene foam beads have a particle size of less than 1 mm, a bulk ratio to apparent size ratio of ≤1.6, and a closed-cell rate of ≥99%. This significantly reduces energy consumption during foam bead molding, and the foam bead molded bodies prepared from these beads exhibit superior appearance, mechanical properties, and thermal insulation properties. The shrinkage rate of the polypropylene foam bead molded bodies is less than 1.5%. This is particularly advantageous for preparing thin-walled or complex-shaped EPP molded products.

The invention belongs to the technical field of building repair materials, and provides water-resistant anti-freezing magnesium phosphate cement repair mortar and a preparation method thereof. The water-resistant anti-freezing magnesium phosphate cement repair mortar is prepared from the following raw materials: modified magnesium oxide, monopotassium phosphate, an admixture, a retarder, fine aggregate, a water reducing agent and water. The preparation method comprises the following steps: (1) dry material mixing: carrying out dry mixing on modified magnesium oxide, monopotassium phosphate, an admixture, fine aggregate and a retarder to obtain a dry material system; and (2) wet mixing and forming: firstly adding half mass of water into the dry material system, stirring, then adding the rest mass of water and the water reducing agent, and continuously stirring to obtain the water-resistant anti-freezing magnesium phosphate cement repair mortar. The repair mortar has excellent water resistance, freezing resistance and mechanical properties. The preparation method is simplified in preparation process and low in production cost, meanwhile, high-value utilization of solid waste can be achieved, and the requirement for rapid repairing of constructional engineering in severe environments such as humid and cold environments is met.

The utility model discloses a stainless steel casting forming technical field's a kind of stainless steel casting forming equipment with quick cooling function, including casting mould, the bottom of casting mould is provided with cooling support assembly, cooling support assembly includes heat insulation pedestal, the bottom of one side of heat insulation pedestal is provided with circulating conveying component, circulating conveying component includes input pump box, circulating conveying component is installed in the bottom of one side of heat insulation pedestal, the scheme is arranged cooling support assembly, wherein the quick cooling cavity in heat insulation pedestal is arranged circulating cooling pipeline, and is matched with input pump box and output pump box to form circulating conveying system, can be outside ultra-low temperature cooling medium high-efficiency circulating conveying to pipeline inside, by the contact cooperation structure of metal heat conduction plate and metal heat conduction strip, and the recessed groove design of the matching of casting mould bottom four around and metal heat conduction strip, can be ultra-low temperature evenly conducted to casting mould, optimizes casting cooling process.

The application relates to an efficient leather vacuum drying machine and a working method thereof, and relates to the technical field of leather processing equipment; the machine body is provided with a plurality of pairs of closed covers and corresponding working plates which are sequentially and spacedly arranged on the machine body, one side of the machine body is provided with a vacuum device for vacuumizing, an output end of the vacuum device is in communication with each pair of closed covers and working plates, a suction hose is arranged between the output end of the vacuum device and each pair of closed covers and working plates, and a control valve is arranged on each suction hose; an air suction pipe is arranged on the suction hose in communication, and the communication position of the air suction pipe and the suction hose is located on the side of the control valve facing the working plate; an end of the air suction pipe is in communication with a standby tank, an electric control valve is arranged on the air suction pipe, and a suction device for vacuumizing is arranged on the standby tank; the application has the effect of improving the working efficiency of the vacuum drying machine.

The invention discloses a liquid cooling driving pump body investment casting process which comprises the following steps: firstly, according to the size and the shape of a pump body, manufacturing a mold with a cavity consistent with the pump body and a loose piece for forming a complex inner cavity structure of the pump body, then injecting wax, molding a wax mold in the mold cavity by adopting a one-time mold splitting molding process, according to the pump body complex inner cavity wax mold, loose pieces are mutually positioned, combined and formed, then wax injection mold splitting is carried out to obtain a wax body, the wax body is connected to a mold head through a pouring gate system to form a tree group, then shell making and dewaxing are carried out on the tree group to form a mold shell, and then roasting, smelting pouring and post-treatment are carried out on the mold shell to form a casting. And the casting is further machined through overhauling, heat treatment, shaping and finish machining, and finally the qualified pump body is obtained if the casting is detected to be correct. Through one-time mold splitting of the wax piece with the complex structure in the inner cavity of the pump body, the mold splitting efficiency is improved, the cost is reduced, meanwhile, the pump body casting is corrected by adopting a one-time composite sizing mold after being subjected to smelting pouring, orderly cooling solidification and heat treatment, and the leakage risk of the pump body casting is greatly reduced.

This application provides a modified photocurable oligomer, its preparation method, and a photocurable 3D printing resin. The preparation method of the modified photocurable oligomer includes the following steps: providing an acrylic monomer, a triblock thermoplastic elastomer, a coupling agent, and a polyurethane acrylate; dissolving the triblock thermoplastic elastomer in the acrylic monomer to obtain a block copolymer mixed solution; adding the coupling agent to the block copolymer mixed solution to obtain a modified block copolymer mixed solution; adding the polyurethane acrylate to the modified block copolymer mixed solution, and mixing to obtain the modified photocurable oligomer. The modified photocurable oligomer, its preparation method, and the photocurable 3D printing resin provided in this application use a triblock thermoplastic elastomer as a toughening reinforcing phase, and chemically modify its surface using a coupling agent, enabling it to form a strong chemical bond interface with the polyurethane acrylate after pre-dispersion in the acrylic monomer.

The application discloses a kind of phosphogypsum road base water stable material and its construction method, by weight fraction, including calcined phosphogypsum 300~2000 parts, cement clinker 300~2000 parts, limestone 50~500 parts, toughening agent 1~10 parts, high-strength water-resistant agent 10~200 parts, sodium bentonite 50~100 parts, glass fiber 1~10 parts;The high-strength water-resistant agent is magnesium chloride, magnesium oxide, dimethyl chlorosilane is added with 1:1:0.05~0.5, the toughening agent is polyvinyl alcohol and EVA is mixed with 1:0.5~1 to form.The water stable material produced by using industrial by-product phosphogypsum calcined building gypsum as raw material has strong water resistance, high compressive strength and surface hardness, and is resistant to cracking caused by expansion;After premixing at construction site, road construction is carried out, the setting time meets the construction requirements, the water-soluble fluorine ion concentration of road surface is less than 3.50mg / L, water-soluble phosphorus pentoxide is not detected, the liquid leached under rainwater washing has no environmental pollution, the water stable material of the application enables the engineering of solid waste to be batched, and realizes the maximum resource utilization of phosphogypsum.

The present application relates to the technical field of film processing, and particularly relates to a temperature control strong attachment flow line for car film production and a composite process thereof. The present application aims to provide a temperature control strong attachment flow line for car film production and a composite process thereof, which integrates electrostatic auxiliary lamination, gradient heat pressing and gradient cooling, effectively eliminates bubbles, reduces internal stress, and realizes high-quality composite between film layers. The temperature control strong attachment flow line for car film production comprises a feeding device for synchronously releasing at least two film substrates to be laminated; a pre-lamination device arranged downstream of the feeding device and used for preliminarily laminating the at least two film substrates; and the pre-lamination device comprises an electrostatic auxiliary lamination unit and a mechanical extrusion lamination unit. The present application achieves the effect of integrating electrostatic auxiliary lamination, gradient heat pressing and gradient cooling, effectively eliminating bubbles, reducing internal stress, and realizing high-quality composite between film layers.

The utility model discloses a widening structure for new and old bridges with large height difference, which relates to the field of widening transformation of old bridges and comprises a first bridge body and a second bridge body. The first bridge body embedded steel bars and the second bridge body embedded steel bars are embedded in the tops of the first bridge body and the second bridge body respectively; the first bridge floor cast-in-place layer and the second bridge floor cast-in-place layer are both poured at the top ends of the first bridge body and the second bridge body; the anchoring steel bars are embedded in the top of the second bridge body and located at the bottoms of the second bridge body embedded steel bars, the lightweight concrete precast blocks are arranged at the top end of the second bridge body, and the outer sides of the lightweight concrete precast blocks are matched with the second bridge body embedded steel bars and the anchoring steel bars correspondingly. The lightweight concrete leveling layer is reasonable and reliable in structure, the lightweight concrete precast blocks are adopted to replace a traditional concrete leveling layer, the weight is reduced by 30%-50%, the dead load of the newly-added leveling layer is controlled within 15% of the live load of an original bridge, and the influence on the original bridge structure is remarkably reduced.

The application belongs to the technical field of refractory materials for blast furnace ironmaking, and particularly relates to a thermal shock cracking resistant taphole clay material and a preparation method thereof. The taphole clay material comprises aggregates, matrix powder and a binder system; the binder system is composed of polysilazane, isocyanate curing agent and B4C micropowder. By introducing polysilazane as the main binder, the application realizes high ceramic yield and low volume shrinkage by using the characteristics of polysilazane being converted into Si-B-C-N ceramic at high temperature. Meanwhile, B4C micropowder is oxidized to generate B2O3 at high temperature, which fills pores, promotes sintering and protects carbon phase, so as to realize volume shrinkage compensation and high temperature strength improvement. The taphole clay material has low shrinkage rate, high cold compressive strength, high high-temperature bending strength and excellent thermal shock cracking resistance, and solves the technical problems of poor volume stability and insufficient high-temperature strength of traditional taphole clay caused by binder carbonization shrinkage.

This invention belongs to the field of weaving equipment technology and discloses a pretreatment device for a circular loom, including a housing with multiple ferrules installed at the bottom. One end of the housing is fixedly installed with an inlet plate having multiple inlet guide holes. Inside the housing, along the yarn travel direction, are sequentially arranged an infrared heating tube group, an atomizing nozzle group, a parallel electrode plate, a simulated weaving guide roller group, a low-temperature plasma generator, a heated pressure roller group, and a cold air cooling unit. The other end of the housing is fixedly installed with an outlet plate having multiple outlet guide holes. This device integrates multiple pretreatment functions into one housing, realizing integrated continuous operation of yarn pretreatment. It can effectively release internal yarn stress, remove surface fuzz from the yarn, improve yarn flexibility and surface quality, thereby reducing the shrinkage rate of the base fabric, reducing yarn breakage during weaving, improving the production efficiency and product quality of the circular loom, and reducing production costs.

A method for improving phase transition temperature of 4D printing high-temperature high-entropy shape memory alloy, comprising the following steps: firstly, forming Ti 25 Zr 12 Hf 13 Ni 25 Cu 18 Co7 high-temperature high-entropy shape memory alloy by using 4D printing technology T S and then heating the printed alloy sample to semi-solid temperature between solidus temperature and liquidus temperature of the alloy T L , keeping warm for 5-15 min, and then rapidly water quenching to obtain semi-solid isothermal heat treatment sample. The preparation method can reduce residual stress of 4D printing forming sample, and prepare high-temperature high-entropy shape memory alloy with high density, few defects and high phase transition temperature.

This invention provides a nickel-core ceramic composite powder, a slurry, a preparation method thereof, and a multilayer ceramic capacitor; wherein the nickel-core ceramic composite powder comprises core-shell particles, the core-shell particles comprising a nickel core and a ceramic layer covering the nickel core, wherein the nickel core and the ceramic layer are bonded together by a coupling agent; the slurry is obtained by mixing the nickel-core ceramic composite powder, a slurry solvent, and a binder; the internal electrode in the multilayer ceramic capacitor can be made from the nickel-core ceramic composite powder or a slurry containing the nickel-core ceramic composite powder.

The application discloses a glue injection polymerization device, a glue injection system, a glue injection method and a wax removal device. The glue injection polymerization device comprises a pressure injection mechanism, and a polymerization mechanism is arranged below the pressure injection mechanism. The pressure injection mechanism is used for pushing the piston of a glue-containing syringe so that the glue is gradually injected into a false tooth model. The polymerization mechanism is used for providing steam so that the glue in the false tooth model is gradually polymerized from bottom to top. The glue injection polymerization device provided by the application realizes the combination of glue injection and glue boiling processes in one device. Since the polymerization mechanism is arranged below the glue pipe seat, the glue at the bottom of the false tooth model is first affected by high temperature to complete polymerization. In this process, the polymerized and solidified glue squeezes out the air in the glue, and this process gradually acts on the glue in the whole false tooth model from bottom to top, so that the generation of air bubbles can be effectively reduced or even avoided, the shrinkage rate of the glue support is reduced, the quality of the glue support after forming is improved, and the yield of the removable denture is improved.

This utility model discloses a diamond press hinge beam casting system, comprising: a core assembly molding system and a gating system. The core assembly molding system uses manual core box making, with partial covering using chromite sand. The core assembly includes multiple sets of outer cores, rod cores, and a central core. The outer skin uses a carbon dioxide ester hardened water glass sand process applied in a molding production line, employing a 3-box + 1-box combination. The gating system combines bottom casting and riser casting. The bottom casting uses a one-to-four reverse pouring method, and the riser casting uses a T-shaped tee method. This utility model meets the casting precision requirements of the product, reduces mold making costs, shortens the production cycle, and improves production efficiency.

The invention belongs to the technical field of packaging materials, and particularly relates to an ultrathin high-speed packaging biaxially oriented polypropylene film and a preparation method thereof. The polypropylene film comprises an extrusion layer I, an extrusion layer II, a core layer, an extrusion layer III and an extrusion layer IV which are sequentially connected from outside to inside. The sealing temperature of the polypropylene film is lower than 90 DEG C, and the sealing requirement of a high-speed packaging machine can be met; the bending modulus of the film exceeds 1800 Mpa, and the high-speed film feeding requirement of a packaging machine is met; meanwhile, the advantages of low friction, high transparency, low shrinkage and the like are realized.

The present application belongs to the technical field of polymer materials, and particularly relates to a low-shrinkage high-transmittance polypropylene composition and a preparation method thereof. The composition is composed of the following raw materials in percentage by weight: polypropylene resin: 29.2-79.85%; polyethylene resin: 10-25%; elastomer: 0-10%; light diffuser: 0-5%; inorganic filler: 10-30%; nucleating agent: 0.05-0.5%; antioxidant: 0.1-0.3%; wherein the polypropylene resin is an impact copolymer polypropylene, and the ratio of the characteristic viscosity of the rubber phase to that of the polypropylene resin is 1-1.2; the polyethylene resin is prepared by using a metallocene catalyst. The present application optimizes the formula of the composition, significantly improves the transmittance, impact resistance and dimensional stability of the polypropylene material on the basis of maintaining excellent mechanical properties, so as to meet the market demand for high-performance polypropylene materials.

The utility model relates to the technical field of decorative base paper, in particular to high-wear-resistance decorative base paper which comprises a base paper body, a base layer is arranged at the bottom of the base paper body, a fireproof layer is arranged on the upper side of the base layer, and a reinforcing layer is arranged on the upper side of the fireproof layer. A nano wear-resistant agent and carbon fiber components are added into the first wear-resistant layer, a compact structure is formed on the surface of the paper by adding the nano wear-resistant agent, the carbon fiber and other components, the wear resistance is remarkably improved, alum is adopted as a bridging agent to enhance the fiber bonding degree, and the anionic neutral dispersed rosin size is matched to improve the bonding strength and reduce the paper shrinkage rate. The second wear-resistant layer is a melamine resin coating, and is cured at high temperature after being impregnated with melamine resin to form a hard and scratch-resistant surface layer, so that the overall wear resistance is higher and the service life is longer through the combination of the first wear-resistant layer and the second wear-resistant layer.

A method for preparing a low-cost and simple-process micro-optical glass device, comprising: step 1: obtaining a silica dispersion liquid, adding an acidic solution into the silica dispersion liquid to adjust a pH value of the silica dispersion liquid, and stirring the same; step 2: adding tetraethyl orthosilicate into the silicon dioxide dispersion liquid, and stirring the same, so as to obtain a sol; adding an alkaline solution into the sol to adjust a pH value of the sol, stirring and leaving the same to stand; step 3: injecting the sol which has been left to stand into a mold, and aging the same, so as to obtain a wet gel; step 4: demolding the wet gel, washing and drying the same, so as to obtain a dried gel; and step 5: sintering the dried gel, so as to obtain a micro-optical glass device; wherein, the solid content of silica in raw materials is not greater than 25.5%. By using the raw materials with a low silica solid content, a micro-optical glass device is prepared by a sol-gel method, achieving a large shrinkage rate; and a glass device having a surface micro-optical structure can be prepared at one time, reducing the cost and simplifying the process.

This invention provides a mixed aggregate mine backfill material of ultra-fine iron tailings sand and steel slag sand and its preparation method, belonging to the field of building materials. The mixed aggregate mine backfill material of ultra-fine iron tailings sand and steel slag sand provided by this invention comprises the following components in parts by weight: 6-13 parts iron tailings powder, 9-20 parts slag powder, 0.5-1 part desulfurization ash, 20-38 parts ultra-fine iron tailings sand, 10-28 parts steel slag sand, 0.6-1.4 parts activator, and 25-41 parts water. The mixed aggregate mine backfill material of ultra-fine iron tailings sand and steel slag sand provided by this invention has a 120-day shrinkage rate as low as 2.12% and a 28-day compressive strength as high as 7.68 MPa, exhibiting low shrinkage and high compressive strength.

This invention provides a high-temperature conductive silver paste for a microcrystalline glass thick-film heating plate, its preparation method, and sintering process. The high-temperature conductive silver paste for the microcrystalline glass thick-film heating plate, by mass percentage, comprises: silver powder: 75-85%; composite glass powder: 1-5%; organic carrier: 10-24%. The composite glass powder comprises component A and component B in a mass ratio of 1-3:1. Component B is silicon micropowder. Component A, by mass percentage, comprises: silicon oxide: 35-50%; boric acid: 20-30%; magnesium oxide: 10-15%; aluminum oxide: 5-10%; titanium oxide: 3-5%; and zirconium oxide: 1-2%. The high-temperature conductive silver paste for the microcrystalline glass thick-film heating plate prepared by this invention has high solderability, strong adhesion, a maximum operating temperature exceeding 450℃, strong resistance to high current impact, high re-firing stability, and excellent overall performance.

An anion exchange membrane having an anion exchange resin layer (3) reinforced by a base sheet (5), characterized in that the anion exchange resin layer (3) contains an anion exchange resin having a pyridinium group obtained by protonating a pyridyl group as an anion exchange group and a vinyl chloride resin as a thickening agent, and the base sheet (5) is a polyethylene woven fabric.