35results about How to "Promote plastic flow" patented technology

The invention discloses a single-point longitudinal vibration controllable progressive forming system for a metal plate. The main shaft of the single-point longitudinal vibration controllable progressive forming system for the metal plate is installed on a rack; a force sensor is installed on the shaft end of the main shaft; a vibration signal generator is connected with a vibration exciter; the vibration exciter is installed below the force sensor; a tool head is connected with the vibration exciter via a connecting rod; a workbench is installed just below the main shaft; the input end of a parameter controller is connected with the force sensor; and the output end of the parameter controller is respectively connected with the vibration frequency and amplitude control port of the vibration exciter as well as the X-shaft driving motor control port and the Y-shaft driving motor control port of the workbench. A single-point longitudinal vibration plasticity forming condition of the plate material is established by combining a forming technology parameter, a vibration mode parameter and a forming force parameter, and the parameter controller is used for monitoring and regulating the forming technology parameter and the vibration mode parameter in real time according to the plate material forming technology state and the vibration plasticity forming condition. The single-point longitudinal vibration controllable progressive forming system for the metal plate, which is disclosed by the invention, has the beneficial effects that the technical defects of single-point progressive forming can be overcome, the technology parameter and the vibration mode parameter can be monitored and regulated in real time according to the plate material vibration plasticity forming condition in the forming process, and efficient and precise progressive forming of the metal plate material can be realized.

The invention relates to a stir friction both-side welding method for a medium-thickness plate and belongs to a novel metal material connection method. The welding method includes the following steps that firstly, magnesium alloy plates to be welded are in butt joint and are fixed to a worktable; secondly; secondly an FSW device is used for performing both-side welding graded welding on the magnesium alloy plates, and primary welding joint welding is performed on a stirring head at the rotating speed omega, the welding speed Vh and the pressing amount h; thirdly, a workpiece is overturned, secondary welding joint welding is performed on the back of a primary welding joint, and welding parameters are identical to those in the second step. According to the stir friction both-side welding method, due to the fact that the initial position of a secondary welding joint is adjusted, the plastic flow of metal can be improved, asymmetry of heating power influence areas on the two sides of cross sections of welding joints is easily avoided, and the mechanical property on connectors is improved. The defect that the root of the medium-thickness plate is not welded thoroughly is overcome, and the possibility that the metal of the surface-layer welding joints is locally overheated is also reduced through twice welding.

The invention discloses an isothermal forging method of a straight bevel gear. A blank and a mold are heated to roughly consistent temperatures respectively, then the blank is placed into the mold and is subjected to forging molding in the mold at the relatively low strain rate, and the straight bevel gear is obtained through aftertreatment, wherein the relatively low strain rate is lower than 0.1 mm / s, and the mold adopts a closed mold forging structure. According to the method, firstly, the blank and the mold are heated to the equal temperature or basically equal temperatures, so that the chilling effect produced when the temperature of the mold is lower than that of the blank is avoided, and the plastic flow of the blank is improved; secondly, the mold adopts the closed mold forging structure, the blank bears three-dimensional compressive stress in the forging process, and thus molding of the blank is facilitated; thirdly, the strain rate is lower than 0.1 mm / s, accordingly, the deformation amount of the blank in unit time is small, deformation is sufficient, and molding of the blank is more facilitated.

The invention discloses an electromagnetic blank holder method suitable for high-speed forming. The method includes the steps that (1) blank holder coil assemblies are placed on end faces of a blank holder portion of a metal sheet part, can be only placed on the upper end face or the lower end face of the blank holder portion of the metal sheet part and can also be placed on the upper end face and the lower end face of the blank holder portion of the metal sheet part at the same time, the blank holder coil assembly placed on the lower end face of the blank holder portion of the metal sheet part is supported by means of a female die, the blank holder coil assembly placed on the upper end face of the blank holder part of the metal sheet part restrains blank holder coils to move through a pressing machine or a bolt fastening structure, and pressure can be applied to the blank holder coil assemblies when moving of the blank coils is restrained; (2) in the high-speed forming process, pulse currents are fed into the blank holder coil assemblies, vortexes are sensed on the blank holder portion of the metal sheet part, and therefore electromagnetic pressure is generated on the blank holder portion of the metal sheet part. The method eliminates the contradiction that in a traditional forming process, blank holder force cannot prevent the metal sheet part from wrinkling, is high and causes high frictional resistance to block shaping flowing of the metal sheet part.

The invention discloses a copper-based powder metallurgical pantograph sliding plate material taking spherical chromium powder as a strengthening phase and a preparation method thereof. The copper-based powder metallurgical pantograph sliding plate material taking the spherical chromium powder as the strengthening phase is prepared from the following components in percentage by mass: 75 to 85 weight percent of Cu, 1 to 10 weight percent of the spherical chromium powder, 1 to 5 weight percent of Pb, 5 to 10 weight percent of Sn, 1 to 5 weight percent of Ni, 0.5 to 2 weight percent of flake graphite and 0.5 to 2 weight percent of molybdenum disulfide. The copper-based powder metallurgical pantograph sliding plate material prepared by the invention has excellent mechanical properties, good wear resistance and self-lubricating performance, low resistivity, high strength and good arc extinguishing performance. The copper-based powder metallurgical pantograph sliding plate material providedby the invention is mainly used for power-taking elements of urban rail transit and low-speed heavy-duty locomotives.

In the third step of joining of the metal members, the pressing force of the rotational tool under rotation is maintained at the third pressing force that is smaller than the second pressing force until a specified period of time elapses after the tip of the pin portion of the rotational tool has reached the specified point that is at a distance from the joining face. Accordingly, the proper plastic flow of the metal member can be generated and thereby the joining strength with a sufficient period of time of agitation can be ensured, by maintaining a high temperature enough to soften the metal member and by preventing the rotational tool from coming into the metal member too deeply or from penetrating the metal member.

The invention discloses a vacuum secondary hot pressing manufacturing technology for a high-strength polycrystalline diamond drawing die. A bushing is obtained by metal powder through vacuum secondary hot pressing, the vacuum degree is 2*10-3-8*10-3 Pa, the pressing pressure is 20-45 MPa, the temperature is increased to 500-550 DEG with the rate of 20-30 DEG C / min, the temperature and the pressure are kept for 10-20min, the temperature is increased to 600-650 DEG C with the rate of 10-15 DEG C / min, the temperature is kept for 10-15 min, the pressure is kept for 15-20 min, and the drawing die is obtained through cooling. The method of vacuum secondary hot pressing is adopted, particles can be scattered and slide through the surface energy and the external pressure, pores in a sintered body are removed, and the compactness of materials is improved; elastic strain in the cold pressing process can be removed, the density of the sintered body can be increased, the elastic failure does not exist, and the adverse influences generated by size increasing after demolding are reduced; the vacuum sintering is neutral sintering of anaerobic and non-reducing gas, combination of interfaces can be improved, and the obtained drawing die bushing is closely attached to a die core and a steel bushing; the gaps of the sintered body can be fully filled with the particles through secondary hot pressing, obtained material cracks are few, and the utilization rate of the die is increased.

The invention relates to the field of paints and discloses a multifunctional paint and a preparation method thereof. The paint is prepared from the following components in percentage by mass: 15-50% of a composite filler, 4-10% of a color-change factor, 0.5-2% of an anti-freezing agent, 35-65% of an emulsion, 0.3-0.5% of a wetting agent, 0.5-2% of an antifoaming agent, 0.2-1% of a thickener, 0.5-2% of a neutralizer, 0.2-1% of an antimycotic agent, 0.4-1% of a dispersing agent, 0.5-1.5% of a coalescing agent, 3-5% of a reducing liquid and the balance of water, wherein the composite filler contains the following components in parts by weight: 5-15 parts of silicate neodymium crystal, 1-10 parts of tourmaline powder, 15-25 parts of calcined diatomite and 1-5 parts of indium-containing rare earth; the thickener contains a cellulose thickener and a polyurethane thickener; and the weight ratio of the cellulose thickener to the polyurethane thickener is 1:(2-4). The harmful gases of formaldehyde and the like in air are absorbed to the surface and the inside of a coating through the calcined diatomite in the multifunctional paint and then effective components of the reducing liquid in the coating are decomposed, meanwhile, anions are released by the tourmaline powder, so that targets of improving the air quality and optimizing the indoor environment are achieved.

The invention relates to an electromagnetic heating type extrusion molding device for a dimpled heat transfer pipe. The device comprises a hydraulic system, a supporting system, a reset system, a pressing head system and a heating system. The device is characterized in that the supporting system is in bolt connection with the hydraulic system; the pressing head system is connected to the lower side of the hydraulic system through a pin shaft; the reset system is installed between the pressing head system and the hydraulic system; the heating system is installed on the right side of the pressing head system. Before the device works, heating treatment is conducted on a light pipe through the heating system, so that the light pipe is softened; when extruding is conduced, driving force is provided for the pressing head system through a hydraulic cylinder, and the pressing head system drives multiple punch heads to extrude the light pipe simultaneously; after extruding is finished, the pressing head system restores to an original state through a tension spring of the reset system, and then the dimpled heat transfer pipe is formed. Compared with the prior art, the softened light pipe is extruded by adopting multiple groups of pressing heads, the extruding force and the residual stress are decreased, the plastic molding limit is increased, therefore, the machining and manufacturing efficiency of the dimpled pipe is improved, and the production cost and the machining difficulty are reduced.

The invention discloses a method for preparing boron carbide ceramic through low-temperature pulse pressurization, which comprises the following steps: (1) drying raw material B4C powder, putting thepowder into a ball mill, carrying out ball milling, and drying and sieving after ball milling to obtain fine-grained B4C powder; and (2) putting the B4C powder in the step (1) into a mold of a pressurization device of a pressurization sintering furnace, vacuumizing or introducing inert gas, performing heating to raise the temperature to 100 DEG C, carrying out pulse pressurization until the temperature reaches 1300-1500 DEG C, stopping pulse pressurization, heating to a sintering temperature, sintering at a constant pressure, and cooling to obtain the fine-grained boron carbide ceramic material with high density. By adopting the pulse pressurization mode, the sintering time can be shortened under the condition that no auxiliary agent is added, the sintering temperature is reduced, the complete densification (the density reaches 98% or above) of the boron carbide powder is realized, and the characteristics of the fine-grained material is maintained.

Disclosed are rotating tools for double-sided friction stir welding that are applied to double-sided friction stir welding, which is a technique for welding two metal plates by rotating a pair of rotating tools, which oppose each other, in opposite directions, a double-sided friction stir welding apparatus that uses the rotating tools, and a double-sided friction stir welding method. A pair of rotating tools for double-sided friction stir welding that are used in double-sided friction stir welding, which is a technique for welding metal plates by using a pair of rotating tools that are each disposed on one of first and second surfaces of an unwelded portion of the metal plates such that the rotating tools rotate in opposite directions, include end portions each of which is formed in a circular and planar shape. The end portions are each made of a material harder than the metal plates.

A static metal seal comprising an outer sealing layer, wherein the outer sealing layer comprises a textured surface that is configured to come into contact with the surfaces that are to be sealed, the textured surface comprising a network of depressions spaced apart from one another on the textured surface, wherein the depressions are blind, do not pass all the way through the outer sealing layer, and do not communicate with one another.

The invention relates to a friction stir double-rivet welding method for dissimilar alloy, which belongs to the technical field of dissimilar alloy material connection, is carried out by adopting friction stir double-rivet welding equipment for dissimilar alloy, and comprises the following steps of: prefabricating a through hole in a connection area by taking a low-melting-point metal material as an upper plate; a large concave shaft shoulder stirring head and a rivet made of the same material as the lower plate are adopted; connecting areas of the dissimilar metal plates are matched and fixed to a welding workbench, rivets are placed into the prefabricated holes, and stirring friction rivet welding is conducted; under the effect of heat production upsetting of the rotary stirring head, the rivet, the upper plate and the lower plate form good metallurgical connection; meanwhile, the rivet upper material is embedded into the upper plate material to form a riveting pier head, the rivet lower material warps upwards to enter the aluminum plate, and the rivet upper material and the rivet lower material jointly form an outer riveting structure; the upper plate material is extruded to the position between the rivet and the lower plate material or the lower plate material is driven into the upper plate material, and an inner riveting structure is formed near a lap joint interface; the mechanical and metallurgical bonding coexisting double-rivet joint is formed, and connection between dissimilar alloy materials is strengthened.

The invention discloses a method for preheating before friction stir welding, which comprises the following steps of: S1, assembling a disc surface and a tire ring which are pre-welded together to form an interference fit rim; s2, the assembled interference fit rim is moved to a welding tool to be fixed; s3, preheating at a welding bead; s4, determining the surface temperature of the weld bead by using a laser thermometer, and completing preheating after the surface temperature reaches 200-250 DEG C; and S5, after preheating is completed, friction stir welding is conducted immediately. By means of preheating assistance, the welding heat input amount can be increased, welding materials can be softened, the requirement for downward pressure is lowered, meanwhile, the welding difficulty can be lowered, abrasion of the stirring head is reduced, the service life of the stirring head is prolonged, the welding axial force and the welding difficulty of high-melting-point metal are lowered, high-speed welding is easy to achieve, and the welding efficiency is improved. And in addition, a proper preheating temperature is adopted, so that the material generates good plastic flow, and the generation of defects such as tunnel holes is avoided.

Belonging to the technical field of metal processing, the invention particularly relates to a metal incremental forming lubricant and a preparation and use method thereof. Directed at the problems ofshort service life of forming heads, poor quality of prepared metal products and the like in the prior art, the invention provides a metal incremental forming lubricant, which comprises, by weight, 70-100 parts of titanium dioxide, 15-30 parts of molybdenum disulfide, 5-10 parts of graphite, 2-8 parts of organic silicon oil, 1-5 parts of lead iodate and 1000-1500 parts of mineral oil. The invention also provides a preparation method of the lubricant, and the raw materials are weighed by weight and then mixed evenly to obtain the product. The lubricant provided by the invention is simple in composition, and the raw materials are economical and environment-friendly. Through proper proportioning, the prepared lubricant realizes optimized distribution of the surface lubricating properties of forming heads, improves the plastic flow of formed materials, improves the service life of the forming heads and the product quality, and has wide application space.

The invention discloses an ultrasonic energy transverse applying device and method based on rolling column and stirring head combination, solves the problem of time delay of ultrasonic vibration and amechanical effect of a stirring head or incapability of realizing effective coupling of the two in the prior art, and has the beneficial effects of improving plastic flowing of metal in the welding process and realizing synchronous coupling of a thermal effect of the stirring head and an ultrasonic softening effect. The ultrasonic energy transverse applying device based on rolling column and stirring head combination comprises a sleeve fixture; the sleeve fixture is connected with an ultrasonic generation mechanism; one end of the sleeve fixture is connected with a pushing mechanism, and a rolling column tool head is arranged at the other end; the stirring head for welding workpieces is arranged at the side part of the rolling column tool head; the axis direction of the stirring head is perpendicular to the axis direction of the rolling column tool head; the pushing mechanism drives the sleeve fixture to move towards the stirring head; and ultrasonic energy is transferred to the stirring head through contact between the rolling column tool head and the stirring head.

The invention discloses a method for connecting metal and a carbon fiber composite material through electric activation-assisted ultrasonic waves, and belongs to the technical field of composite processing and preparation of carbon fiber composite materials / metal materials. Firstly, pulse current is applied to the to-be-compounded surface of a metal plate, metal makes contact with conductive carbon fibers to generate micro-area discharge, interface local high temperature can be achieved, a to-be-connected interface is activated, and the chemical metallurgical reaction of the interface is promoted. Secondly, utilizing ultrasonic high-frequency vibration and friction heat to promote plastic flow of a resin matrix of an interface to be connected, and realizing connection between the resin and the metal and connection between the carbon fibers and the metal under the action of a certain pressure;

The invention provides a high-performance component twisting-extruding forming device, and belongs to the technical field of metal plastic machining. The high-performance component twisting-extrudingforming device comprises an extruding forming part, a twisting shearing part, a control part and a detection part. The extruding forming part applies a load through an extruding shaft to enable a blank to conduct metal flow in an extruding barrel and an extruding die to be formed; the twisting shearing part transmits torque to a twisting head through jointing of a servo motor, a worm gear reducer,a torque sensor, a coupler and a shaft, and the deformed blank achieves grain refinement under the high-pressure twisting effect of the twisting head; the control part achieves matching of twisting and extruding; and the detection part obtains extruding force of the extruding shaft, the torque of a twisting shaft, the extruding stoke and the twisting angle, and transmits obtained signals to a computer. A component is subjected to the combined effect of a pressure machine load and twisting shearing deformation in the forming process, and single-pass near-net forming of the high-performance component is finally achieved.