41results about How to "Offset tensile stress" patented technology

The invention discloses a high-strength domestic ceramic prestressed coating material. The high-strength domestic ceramic prestressed coating material consists of a base material and an adhesive solution under the condition that the ratio of the base material to the adhesive solution equals to 1 g: 4-8 mL; the base material comprises the following raw material components: 10-20 wt% of Al2O3, 45-70wt% of SiO2, 12-28 wt% of MgO and 2-10 wt% of ZnO; and the adhesive solution is a solution of one or more of CMC, PVA, PVB or water glass, and the concentration of the adhesive solution is 5-10 wt%.The invention further discloses a preparation method and a ceramic product of the high-strength domestic ceramic prestressed coating material. A surface coating mode is adopted, by adjusting and optimizing the ratio of the coating raw materials, pressure stress is introduced on the surface of a ceramic blank by coated layer coating treatment, and therefore, the integral strength of ceramics is improved remarkably. Raw materials are toxic-free and pollution-free, the process is simple and practicable, and industrialized application and popularization are facilitated.

The invention provides a method for filling a hinge joint of a fabricated prestressed hollow beam slab, and belongs to the technical field of bridge engineering. The method comprises the steps as follows: inserting a screw type blocking strip into a bottom gap of the hinge joint, wherein the top surface of the screw type blocking strip comprises two split parts, one part is lapped on the other part, the length of the lapping position is 3-5 cm, and rubber strips are arranged on wing plates on the two sides of the screw type blocking strip; filling the middle of the hinge joint with micro-expansion concrete; when the concrete of the hinge joint reaches enough age period, filling the top of the hinge joint with bituminous grout; and when the bituminous grout reaches the design performance, pouring a pavement layer on the top surface of the hollow beam slab. When the micro-expansion concrete is poured, the top surface of the screw type blocking strip is open, so that the space of a vertical column is communicated with that of the hinge joint and the screw type blocking strip is stabilized by the rubber strips on the wing plates and the self weight of the concrete of the hinge joint; and the middle of the hinge joint is filled with the micro-expansion concrete, so that the space of the hinge joint is closed for a long time and the problem of water seepage due to premature failure of the hinge joint is solved.

The invention provides a preparation method of a reinforced ceramic three-dimensional constraint coating. The method comprises the following steps that 1, sand blasting equipment is adopted to performsand blasting coarsening treatment on the surface of a ceramic matrix; 2, fly dust on the surface of the ceramic matrix subjected to the sand blasting treatment in the step 1 is cleared, the surfaceof the ceramic matrix is cleaned with ultrasonic waves, and then drying is conducted; 3, spraying raw materials are crushed into powder, and weighing and taking 250 g are conducted for spraying; and 4, spraying treatment is conducted on the surface of the ceramic matrix, and the spraying treatment comprises plasma spraying and supersonic flame spraying. The coating prepared through the method andceramic have high bonding strength, when the ceramic is impacted, the coating breaks along with the ceramic, energy is absorbed, so that crack propagation is prevented, in addition, a fracture of thecoating can change the ceramic crack trend, a crack propagation area is increased, and the toughness is improved.

The invention discloses an automatic deposition device and method applied to the outer surface of an environment-friendly container nozzle. The automatic deposition device comprises a welding box, a mechanical arm, a welding rod box and a rotating device; and through a controller, the mechanical arm can achieve rotating, pitching and telescopic operation to automatically clamp a welding rod, and is matched with a rotating shaft to conduct omnidirectional deposition on the outer surface of the nozzle. The welding box is ventilated through a three-way valve, thus the whole welding box is in theprotective atmosphere of inert gas, waste of the inert gas in the traditional welding deposition process can be reduced, and the phenomena of deposition metal oxidation and air holes caused by instability of inert airflow in the welding process can also be avoided; and through the automatic device, the outer surface of an environment-friendly container is evenly and fully covered with a nickel-based alloy 690, and a residual pressure stress layer is formed on the outer surface of the nozzle to improve the hardness and corrosion resistance of the outer surface of the environment-friendly container nozzle.

The invention discloses a method for improving silicon chip warping degree. The method comprises the following steps: step one: a pre-metal dielectric layer is formed on a silicon substrate, and a contact hole penetrating through the pre-metal dielectric layer is formed in the pre-metal dielectric layer; step two: a layer of metal connecting layer is deposited on the pre-metal dielectric layer and the contact hole; step three: rapid heat annealing processing is performed on the metal connecting layer; step four: plasma etching is performed, and a metal natural oxide layer naturally formed on the surface of the metal connecting layer is removed; and step five: a titanium nitride blocking layer is deposited on the upper surface of the metal connecting layer. Warping degree of silicon chips can be effectively improved by the method so that difficulty in silicon chip production flow is reduced.

The invention discloses concrete, which comprises the following components: 270-290kg of cement, 178-205kg of water, 528-560kg of fine aggregate, 1200-1350kg of coarse aggregate, 3.5-5.6kg of pumping aid, 27-32kg of swelling agent and 101-116kg of coal ash. The invention also discloses a cracking-resistant pouring method by adopting the concrete disclosed by the invention. The cracking-resistant pouring method comprises the following steps: S1: adding ice blocks into the concrete for stirring, wherein the addition of the ice blocks is 35-51kg/m<3>; S2: continuously pumping evenly stirred concrete into a die cavity, and evenly vibrating until the whole die cavity is vibrated. The concrete disclosed by the invention can be suitable for large-volume concrete pouring, heat of hydration is lowered, and the heat retaining property of the concrete is improved. If the cracking-resistant pouring method disclosed by the invention is adopted, the temperature of the concrete can be evenly distributed, the heat retaining property of the concrete is good, the cooling speed of the concrete is low, the temperature difference of each layer of the concrete is reduced, the heat expansion and cold contraction of each layer of the concrete tends to be synchronous, and the interior of the concrete can be prevented from cracking due to the temperature difference.

The invention provides a compound admixture for anti-crack limestone powder and a preparation method of the compound admixture. The compound admixture comprises, by mass, 60-70 parts of limestone powder, 28-40 parts of coal ash, 1-2 parts of polypropylene fibers and 0.1-0.2 part of triethanolamine. By the compound admixture for the anti-crack limestone powder, concrete contraction can be reduced and concrete anti-crack performance can be improved while working performance and mechanical performance of concrete are guaranteed, so that durability of limestone powder concrete is improved, and application of the limestone powder to the concrete is widened.

The invention discloses a surface deformation-enhanced non-tempered axle shaft manufacturing method which comprises the steps of raw material preparing, forging and cooling controlling, local induction normalizing, machining, surface induction quenching and tempering and surface deformation strengthening treatment. 38MnVS non-tempered steel is adopted as raw materials of an axle shaft; a forging and cooling controlling technology is used for forging forming of the non-tempered steel, and uniform microstructures are obtained by local induction normalizing after forging; the axle shaft is then machined through machining; surface induction quenching and tempering are carried out on the surface of the axle shaft; and surface deformation strengthening treatment is carried out, in other words, an impact head with the ultrasonic frequency and high energy density at the room temperature is used for conducting surface impact strengthening, the pressing amount of the impact head on the surface of a workpiece is controlled, a deformation strengthening layer is formed on the surface, the surface deformation layer depth is controlled to be 20 microns to 100 microns, and finally the non-temperedaxle shaft with good tissue uniformity and good fatigue and wear resistance is obtained.

The invention provides a gradient composite cubic boron nitride material and a preparation technology and application thereof. The material is manufactured by sintering cubic boron nitride, titanium carbide, aluminum and cobalt as raw materials, and material is of three layers of symmetric gradient structures symmetric about the middle layer, wherein the material is prepared from, by volume, 70-80% of cubic boron nitride, 10% of titanium carbide, 5-10% of aluminum and 5-10% of cobalt, wherein the cubic boron nitride is adopted as a matrix, the titanium carbide is adopted as a ceramic binding agent, and aluminum and cobalt are adopted as metal binding agents. The raw material component contents of symmetric layers symmetric about the middle layer are the same, and the thickness is symmetrically distributed. The material has the high tenacity and corrosion resistance, a tool better adapts to high-speed cutting and wear-resisting part machining, and the wider application prospect is achieved.

The invention relates to a stamping die and a prestress punching process thereof. The stamping die is used for punching a steel plate and comprises a female die, a male die matched with the female dieand a second-stage step positioned above a first-stage step and used for punching the steel plate, wherein a stepped punch is fixed to the male die and is provided with the first-stage step positioned at the lowest end and used for extruding the surface of the steel plate, and the height h of the first-stage step is 1/4-1/3 of the thickness t of the steel plate. By means of the stamping die and the prestress punching process thereof, layering can be decreased, and further block falling is decreased.

The invention relates to the technical field of building materials and provides a grouting material for a sound barrier backboard. The grouting material comprises the following raw materials (by weight): 15-25 parts of Portland cement, 30-40 parts of fly ash, 50-70 parts of building rubbish, 10-15 parts of water and 0.61-1.08 parts of additives. The grouting material has advantages of wide sourcesof raw materials, high utilization rate of solid wastes, low cost, rapid hardening, early strength, slight expansion, strong bonding force, good heat stability and the like, and can be used as a binder for bonding or reinforcement of engineering equipment. The sound barrier backboard is provided with multiple reinforcing holes. after the backboard is maintained to design strength, the backboard is tensioned with pre-stress steel bars or steel strands, and then the grouting material is injected to glue the pre-stress steel bars or steel strands with the sound barrier backboard as a whole. Thus, the sound barrier backboard is safe and stable and durable.

The invention relates to a metal plate shearing edge rolling strengthening method and a plate-shaped part manufactured through the same. The method comprises the steps that a rolling wheel is installed on rolling equipment, the rolling wheel is driven to move to make contact with a shearing edge of a metal plate, and the rolling wheel is enabled to keep thrust F in the moving direction of the rolling wheel; and the metal plate is driven to move close to the rolling wheel in the direction perpendicular to the thrust F, meanwhile, the rolling wheel rolls the edge of the shearing edge to form a chamfer, and the included angle between the rolling face of the rolling wheel and the plate face of the metal plate ranges from 30 degrees to 45 degrees. According to the metal plate shearing edge rolling strengthening method and the plate-shaped part manufactured through the same, burrs on the edge of the shearing edge can be removed, the shearing edge can be thinned in the thickness direction, residual pressure stress is formed on the whole shearing edge, and therefore the fatigue strength of the shearing edge of the plate-shaped part is greatly improved.

The present invention relates to a laser deposited nickel base alloy powder, belonging to the field of metal surface treatment material technology. It is characterized by that in its interior some raw material components capable of in-situ forming negative thermals expansion coefficient substance can be doped. The described raw material components capable of in-situ forming negative thermal expansion coefficient substance are Al2O3, Cu, ZrO2 and V2O5 or ZrO2 and WO3. The added quantity of Al2O3 and Cu is 1-5% of nickel base alloy weight, the mole ratio of Al2O3 and Cu is 1:2, the added quantity of ZrO2 and V2O5 is 1-10% of nickel base alloy weight, the mole ratio of ZrO2 and V2O5 is 1:1, and the added quantity of ZrO2 and WO3 is 1-10% of nickel base alloy weight, the mole ratio of ZrO2 and WO3 is 1:2. In the course of quick solidification of laser deposition the above-mentioned all components can in-situ produce the compounds of CuAlO2, ZrV2O7 or ZrW2O8 with negative thermal expansion coefficient.

The invention discloses a steel-concrete with ultrahigh performance joint section and a manufacturing method thereof. The steel-concrete with the ultrahigh performance joint section comprises a jointbeam, one end of the joint beam is connected with a steel beam, the other end of the joint beam is connected with a concrete beam, and the connection part between the joint beam and the steel beam isprovided with a bearing plate; according to the manufacturing method, the sectional dimensions of the steel beam and concrete beam, the length of the joint beam and the sectional dimension of the bearing plate are selected according to the design requirements; the steel-concrete with ultrahigh performance joint section and the manufacturing method thereof have the advantages that the problems of the complex structure, uneven stiffness transition, high construction difficulty and the like of the steel-concrete joint section can be solved, the structure is simple, and the steel-concrete joint section is safe and reliable.

The present invention discloses a novel rotor applied to a high-speed permanent magnet motor. Part of a circular rotating shafts are changed to a polygonal rotating shaft, the apex of the polygon is inlaid into a main permanent magnet to perform circumferential fixation of the permanent magnet so as to increase the adsorption power between the permanent magnet and the rotating shaft, enhance the radial fixing of the permanent magnet to resist the centrifugal force in a high rotation speed, improve the air-gap field waveform and reduce the loss. A non-magnetic copper ring is modified to an approximate cup-shaped structure to achieve axial and radial fixing of the permanent magnet while achieving non-magnetic and dynamic balance functions. A common rotor sheath fixing device is omitted to simplify the system structure. The omission of the sheath reduces the equivalent gas length to obtain a larger electromagnetic torque in the same motor dimension parameters so as to increase the power density of the motor. The problem of the fixing of the rotor permanent magnet is solved, the utilization efficiency of the permanent magnet is improved and the operation reliability of the motor is improved to facilitate lightweight of the high-speed permanent magnet motor and facilitate improvement of the operation speed of the motor and improvement of the performances of the motor.

The invention discloses a welding process for a prepressing stress bimetal centrifugal casting composite pipe end flange. The welding process comprises the following steps that a groove is formed in the welding face of the flange, and the flange is preheated evenly before welding and is heated to a certain temperature; then the flange is installed at the end of a bimetal centrifugal casting composite pipe, and the flange is fixed to the bimetal centrifugal casting composite pipe in a spot welding mode; and then the flange and the bimetal composite pipe are connected through circular welding. The flange welded by the welding process can form certain pressure stress on the composite pipe, thus the problem of interlaminar separation of the composite pipe due to welding residual stress after welding of the bimetal composite pipe end flange can be avoided effectively, and the reliability of a connector of the double-layer bimetal centrifugal casting composite pipe end flange is improved greatly.

The invention relates to an inverted arch prefabricated assembly structure suitable for a loess highway tunnel and a construction method.The inverted arch prefabricated assembly structure comprises prefabricated inverted arch units, prestressed tendons are arranged at the tops of the prefabricated inverted arch units in a penetrating mode, and embedded steel plates used for being connected with grouting steel pipe piles are arranged at the bottoms of the prefabricated inverted arch units; each prefabricated inverted arch unit comprises a plurality of prefabricated blocks which are spliced and connected, and the outer ends of the two prefabricated blocks on the outermost side extend to form arch foot parts; the construction method comprises the steps of excavating the loess tunnel, carrying out splicing construction on the inverted arch prefabricated splicing structure, installing the prestressed tendons, tensioning and fixing the prestressed tendons, pouring the inverted arch filling layer and laying the plastic concrete buffer layer. Compared with the prior art, the method has the advantages that differential settlement of the arch springing relative to the middle of the inverted arch can be effectively reduced, and the like.

The invention discloses a manufacturing method of a trench metal oxide semiconductor barrier Schottky diode device. The method comprises the following steps: providing a wafer substrate; forming an epitaxial layer on the wafer substrate; forming a plurality of groove type polycrystalline structures at intervals in the epitaxial layer; forming a surface film layer on the epitaxial layer; performing ion sputtering to form a metal film layer on the surface film layer, wherein first processing is performed on the epitaxial layer so as to increase the pressure stress of the epitaxial layer on the wafer substrate, and/or second processing is performed on the surface film layer so as to increase the density of the surface film layer. According to the method provided by the invention, by increasing the pressure stress of the epitaxial layer on the wafer substrate and/or increasing the density of the surface film layer, the tensile stress generated by forming the metal film layer through subsequent sputtering is counteracted and/or the stress strain resistance of the wafer is enhanced, the buckling deformation of the wafer is avoided, and the flatness of the wafer is improved.