297 results about "Cooling rate" patented technology

The invention relates to a preparation method of bainite steel with high toughness and strength at low temperature, and the strength and toughness of the bainite steel at low temperature are improved by designing process parameters and steel ingot components. The bainite steel with high toughness and strength at low temperature is finally obtained by designing the components of the steel ingot, avoiding the addition of elements such as nickel, molybdenum and vanadium, reducing the material cost and the processing difficulty and accurately controlling the cooling rate of heat treatment. The prepared bainite steel is composed of strip-shaped bainite and thin strip-shaped retained austenite, and the volume fraction of the retained austenite is 5-10%. The tensile strength is not lower than 1240 MPa, the normal-temperature impact is not lower than 120 J, and the impact toughness at-40 DEG C is not lower than 80 J.

The invention belongs to the technical field of functional materials, and particularly relates to ultra-thick tabular tungsten oxide and a preparation method thereof.The preparation method of the ultra-thick tabular tungsten oxide comprises the following steps that S1, ammonium tungstate is added into deionized water and stirred to be dissolved at the temperature of 70-90 DEG C, and a clarified ammonium tungstate solution is obtained; s2, cooling the clarified ammonium tungstate solution to normal temperature at a cooling rate of 0.5-2 DEG C / h, and then carrying out suction filtration to obtain plate-shaped ammonium tungstate crystals; s3, calcining the tabular ammonium tungstate crystal to obtain ultra-thick tabular tungsten oxide; ammonium tungstate is adopted as a raw material, controllability is high, tungsten oxide which is uniform in particle size and complete in plate shape is obtained through optimized crystallization and calcination, the purity is larger than or equal to 99%, the problems that traditional tungsten oxide is agglomerated and disordered in shape are solved, functional adaptability is high, the plate-shaped structure can be directionally oriented, the dielectric performance, the breakdown performance and other performance are improved, and the method is suitable for multiple high-end scenes; parameters are easy to control, and operation is simple, green and safe.

The invention discloses an annealing treatment method for low-carbon steel, and relates to the technical field of metallurgical engineering. Comprising the following steps that steel to be annealed is placed in an annealing furnace with the preset temperature to be subjected to annealing treatment, and the annealing furnace comprises a heating section, a heat preservation section and a furnace cooling section which are continuously arranged in the moving direction of the steel; the preset temperature of a heating area is 690-715 DEG C, the preset temperature of a heat preservation area is 750 DEG C, and the preset temperature of a furnace cooling area is 730-525 DEG C; and the residence time of the steel in a heating section, a heat preservation section and a furnace cooling section is adjusted, the residence time of the steel in the heating section is 1.3-1.6 h, the residence time of the steel in the heat preservation section is 3.0-3.6 h, the residence time of the steel in the furnace cooling section is 2.9-3.5 h, and the cooling rate is 64-77 DEG C / h. By means of the method, the plasticity and toughness of the large-specification low-carbon steel can be remarkably improved, and the cold forging machining performance of the large-specification low-carbon steel is ensured.

This utility model discloses a casting-rolling composite system, belonging to the field of casting and rolling technology. It includes a casting mill, a casting nozzle, a flow channel, and a first heating device. The upper casting roll of the casting mill has a larger diameter than the lower casting roll. The upper casting roll is a solid roll with the first heating device on one side, while the lower casting roll has internal cooling water pipes. The casting nozzle includes upper and lower lip plates, with the lower lip plate extending longer than the upper lip plate, forming a stepped staggered layout. An open feeding channel is formed between the upper lip plate and the upper casting roll. This utility model achieves asynchronous rolling through a system of different diameter rolls, increasing the actual deformation of the strip with higher deformation resistance and reducing the uneven deformation of the two metals during the casting and rolling process. Heating the upper casting roll raises the strip temperature, reducing the melt cooling rate. Cooling the lower casting roll shortens the contact arc length between the melt and the lower casting roll, extending the contact time between the melt and the strip, improving the wetting effect, and significantly enhancing the bonding quality and stability of the composite interface.

This invention relates to the field of welding technology, specifically disclosing a low-temperature welding method for thin-walled plates used in lightweight automotive components. The welding method includes the following steps: S1: Raw material preparation, taking raw material, preparing a constant-temperature welding chamber and welding equipment, and a heating gun; S2: Raw material transfer, placing the raw material and welding equipment in the constant-temperature welding chamber; S3: Raw material cleaning, grinding the welding area of ​​the raw material to remove dirt, oxide scale, etc. This invention avoids the problems of excessive temperature difference and rapid cooling rate during welding of thin-walled plates under low-temperature external conditions by setting a constant-temperature welding chamber and limiting its ambient temperature to no lower than 0℃, preferably 7℃. Furthermore, the sealed constant-temperature environment ensures uniform and stable temperature in the welding space, preventing stress accumulation in the weld and base material due to environmental temperature changes, thereby reducing appearance defects such as warping, deformation, and wrinkles in the thin-walled plate.

A hot-rolled steel sheet is provided comprising a predetermined chemical composition and a metallic structure comprising, in area ratio, pearlite: 90 to 100%, pseudo-pearlite: 0 to 10% and pro-eutectoid ferrite: 0 to 1%, wherein the pearlite has an average lamellar spacing of 0.20 µm or less, and the pearlite has an average pearlite block size of 20.0 µm or less.A method is provided for producing a hot-rolled steel sheet comprising heating a plate to 1100°C or more, rolling it by hot rolling, wherein a finish roll exit side temperature is 820 to 920°C, cooling the steel sheet by primary cooling to a point Ae1 by an average cooling rate of 40 to 80°C / s, then cooling the steel sheet by secondary cooling from point Ae1 to a coiling temperature at an average cooling rate of less than 20°C / s, and coiling the steel sheet at a coiling temperature of 540 to 700°C.

This invention relates to a method for preparing ultra-pure smelting of high-strength and high-toughness special steel at ultra-low temperatures. The chemical composition (wt%) is controlled as follows: C≤0.01%, Si≤0.05%, Mn≤0.05%, S≤0.005%, P≤0.005%, Ni: 17.5~18.5%, Co: 8.0~9.0%, Mo: 3.0~3.8%, Al: 0.05~0.15%, Ti: 0.20~0.35%, H≤1.0 ppm, O≤16 ppm, N≤15 ppm, with the balance being Fe and other unavoidable impurities. Core Technology: A five-element synthetic slag system of CaO-SiO2-Al2O3-MgO-CaF2 is introduced during the VIM stage. Utilizing the high-speed directional solidification effect of VAR steady-state remelting, and through matching the smelting environment and cooling rate, the coarse, brittle titanium sulfide phase is transformed into finely dispersed Al-Mg-Ti-S-O multiphase composite oxides. This achieves composite modification of inclusions and reduces their number density from 45 inclusions / mm². 2 Reduced to 8.5 pieces / mm 2 It effectively eliminates the hazards of large particles >4μm. The average grain diameter of the original austenite is refined from 42.37μm to 26.38μm, the elongation of the material reaches 21.06%, and the impact energy is as high as 143.63J, significantly improving the resistance to brittle fracture and possessing extremely high engineering application value.

A method for producing a steel sheet, the method containing the following successive steps:providing a cold-rolled steel sheet, the chemical composition of the steel containing in weight %: 0.15%≤C≤0.23%, 2.0%≤Mn≤2.8%, 1.0%≤Si≤2.1%, 0.02%≤Al≤1.0%, with 1.7%≤Si+Al≤2.1%, 0≤Nb≤0.035%, 0≤Mo≤0.3%, 0≤Cr≤0.4%, the remainder being Fe and unavoidable impurities,annealing the steel sheet at an annealing temperature TA so as to obtain a structure comprising at least 65% of austenite and up to 35% of intercritical ferrite,quenching the sheet at a cooling rate of at least 20° C. / s from a temperature of at least 600° C. down to a quenching temperature QT comprised between Ms−170° C. and Ms−80° C.,heating the sheet up to a partitioning temperature PT between 350° C. and 450° C. and maintaining the sheet at this temperature for a partitioning time Pt comprised between 80 s and 440 s,immediately cooling the sheet down to the room temperature,the steel sheet having a final microstructure consisting of, in surface fraction:between 40% and 70% of tempered martensite,between 7% and 15% of retained austenite,between 15% and 35% of ferrite,at most 5% of fresh martensite,at most 15% of bainite.

The invention discloses a growth method of an alloy metal single crystal, which comprises the following steps: loading an alloy raw material containing a target alloy metal single crystal into a crucible, placing the crucible in a vacuum furnace, purifying the atmosphere in the vacuum furnace, and filling protective gas; heating until the alloy raw material is fully molten, filling set gas to normal pressure, and keeping the temperature to enable the molten liquid to reach a saturated state; cooling at a set cooling rate to form crystals on the surface of the melt; and naturally cooling to room temperature, taking out the crucible, and transferring and treating the surface crystal to obtain the alloy metal single crystal. A set gas is introduced into alloy melt or a crucible material is used for dissolution, two-dimensional single crystals are formed on the surface of the melt in the cooling process, and the two-dimensional single crystals serve as a template to induce metal single crystals to grow from the surface. The method is simple in principle, novel and easy to operate.

This invention relates to the field of rail manufacturing technology, specifically disclosing a turnout rail with uniform hardness distribution on both sides of the rail head and its manufacturing method. The manufacturing method includes: online heat treatment of the rolled rail, which includes: an accelerated cooling stage: when the temperature of the rail top surface of the rolled rail is between 720 and 840°C, the rail top surface, the long leg side of the rail head, and the short leg side of the rail head are accelerated to 460 to 520°C, wherein the cooling rate of the rail top surface is 1.5 to 3.0°C / s, the cooling rate of the long leg side of the rail head is 2.0 to 3.0°C / s, the cooling rate of the short leg side of the rail head is 2.5 to 3.5°C / s, and the cooling rate difference between the short leg side and the long leg side of the rail head is 0.3 to 0.7°C / s; and an air cooling stage: the rail cooled in the accelerated cooling stage is air cooled to room temperature. This invention can produce turnout rails with uniform hardness distribution on both sides of the rail head, thereby improving the stability of turnout rails during service.

The invention discloses a cold rolling process of an aluminum-based silicon carbide coil material. The cold rolling process comprises the following steps: carrying out surface treatment and coiling on a hot-rolled coil material; after the protective film is removed online, cold rolling-annealing I circulation is conducted, the single-pass rolling reduction of cold rolling is 5%-10%, the unit tension is 10%-30% of the yield strength of the material, the speed is smaller than or equal to 15 m / min, heat preservation is conducted for 1-2 h at the temperature of 430-480 DEG C in annealing I, and the heating and cooling rate is smaller than or equal to 10 DEG C / min; then edge cutting is carried out to remove edge cracks; the heating and cooling rate of the annealing II is smaller than or equal to 8 DEG C / min, and the heat preservation time is shorter than that of the annealing I; performing surface treatment after annealing II; and finally, finished product cold rolling is conducted, the single-pass rolling reduction is 5%-8%, and the speed is 5-10 m / min. By means of optimized multi-pass small rolling reduction rolling, staged temperature control annealing and tension control, the technical problem that the aluminum-based silicon carbide composite material is prone to cracking and strip breakage in the continuous cold rolling process is solved.

The invention provides a technology for improving the quality of a brass continuous casting ingot. The technology comprises the following steps that S1, Cu, Pb, Fe, Al and CuMg20 raw materials are weighed; s2, the raw materials are smelted, brass flux is scattered into the raw materials, slag is fished out after stirring, then the surface of molten copper is covered with graphite flakes, then CuMg20 is added into furnace water for deoxidation and desulfurization, finally, the temperature of the smelted molten copper is kept, and argon is adopted for protection; s3, the molten brass is stably introduced into a high-purity side liquid inlet graphite mold and evenly stirred, and the traction speed and the cooling rate are controlled so that a continuous and defect-free hollow cast ingot can be drawn out; and S4, saw cutting is conducted, specifically, the drawn hollow cast ingot is subjected to saw cutting and purging, and the brass hollow cast ingot is obtained. According to the method, common defects such as air holes and inclusions in the cast ingot are effectively reduced, the internal organization structure of the cast ingot is remarkably improved, the cast ingot is more compact and uniform, and meanwhile the cost input in the production process is greatly reduced.

This utility model relates to the field of silica slurry technology, and more particularly to a silica slurry cooling device, comprising a cooling chamber, a disassembly base provided inside the cooling chamber, a coil for storing coolant installed on the disassembly base, a stirring chamber provided inside the cooling chamber, with the coil in contact with the outer wall of the stirring chamber, a rectangular rotating rod provided inside the stirring chamber, and multiple stirring paddles fixedly connected to the rectangular rotating rod; it also includes a drive assembly, which is disposed on the stirring chamber and is used to drive the rectangular rotating rod to rotate and stir the silica. This utility model, through the design of the drive structure, spring, and cross shaft, etc., compared with the cooling methods in the prior art, provides a dual-action mechanism that ensures the stability of the cooling rate and avoids the problem of uneven cooling caused by slurry agglomeration, thus providing a consistent slurry foundation for subsequent processing steps.

This invention relates to a method and system for monitoring the temperature during the construction of large-volume concrete. Specifically, it involves acquiring real-time temperature sequence data from multiple temperature sensors distributed within the concrete structure; determining the scale of the volumetric point distribution based on the current temperature change rate using the real-time temperature sequence data from the temperature sensors; obtaining the filtered temperature sequence from each temperature sensor using a volumetric Kalman filter that employs a simplified heat conduction model in state prediction; calculating a spatial tension parameter field based on the filtered temperature and spatial coordinates of the temperature sensors, combined with the distance between the temperature sensors and the surface of the concrete structure; constructing a three-dimensional temperature field for the entire concrete structure using a tension spline interpolation method based on the spatial tension parameter field; and calculating the maximum temperature difference between the core region and the surface region of the structure, as well as the average cooling rate at a specific location on the structure surface within a preset time period, based on the three-dimensional temperature field.

This invention provides a 5-series aluminum alloy sheet and its preparation method, relating to the field of aluminum alloy technology. The preparation method includes: S1, mixing the metal raw materials of the 5-series aluminum alloy sheet according to a specified ratio and sequentially melting and casting to obtain an aluminum alloy ingot; S2, sequentially subjecting the aluminum alloy ingot to homogenization treatment, hot rolling treatment, first cold rolling treatment, intermediate annealing, and second cold rolling treatment to obtain a cold-rolled sheet; S3, sequentially subjecting the cold-rolled sheet to final annealing, cooling treatment, and straightening treatment to obtain the 5-series aluminum alloy sheet; wherein the Fe element content in the 5-series aluminum alloy sheet is not less than 0.25% by mass, the final annealing temperature is 520~550℃, the final annealing holding time is 10~60s, the final annealing heating rate is 5~15℃ / s, and the cooling rate of the cooling treatment is 8~16℃ / s. The prepared 5-series aluminum alloy sheet exhibits excellent mechanical properties, formability, and surface quality.

The invention relates to the technical field of preparation of ceramic cutters for electrical porcelain fettling, and discloses a preparation method of a precisely formed ceramic cutter for electrical porcelain fettling, the method comprises the following steps: weighing raw materials according to mass percentage, the raw materials comprising Al2O3, clay, CaCO3, an additive 1 and an additive 2; mixing the weighed raw materials, deionized water and ballstone according to a specific mass ratio, and putting the mixture into a ball milling tank for full ball milling to obtain ceramic slurry; slowly injecting the prepared ceramic slurry into a mold, standing, demolding, drying a demolded cutter blank in the shade at a specific temperature, and polishing, modifying and removing burrs after drying in the shade to obtain a to-be-sintered blank; and putting the obtained to-be-sintered blank into a box-type furnace, heating to a sintering temperature according to a specific heating rate, carrying out heat preservation, then cooling according to a segmented cooling rate, and finally, carrying out furnace cooling to obtain the precisely-formed electric porcelain fettling ceramic cutter. According to the invention, the fluidity of the Al2O3-based ceramic slurry and the mechanical property of the cutter are improved, and the precise forming effect of the electroceramic fettling cutter with a complex structure is met.

The invention relates to the field of rapid solidification of ultra-fine grain industrial silicon, and discloses a rapid solidification process of ultra-fine grain industrial silicon based on gas atomization, which comprises the following steps: S1, placing an industrial silicon raw material in a smelting device, heating until the industrial silicon raw material is completely molten to obtain a pure silicon melt, and refining the pure silicon melt; s2, gas atomization and rapid solidification: conveying the refined silicon melt into an atomization device through a flow guide pipe, atomizing the silicon melt by adopting optimized high-pressure inert gas to form micron-order or submicron-order liquid drops, and carrying out high-speed cooling of the high-pressure inert gas flow to obtain the high-speed or submicron-order liquid drops. The average cooling rate of the silicon liquid drops stably reaches and exceeds 106K / s; s3, grain inhibitor introduction and dispersion strengthening; and S4, carrying out thermomechanical treatment and grain boundary engineering. Compared with the prior art, the method has the advantages that the collaborative regulation and control process of rapid solidification, dispersion strengthening and grain boundary engineering is integrated, so that remarkable refining and performance improvement of industrial silicon grains are realized.

The invention discloses a method for accurately controlling the cooling control temperature of a steel plate with the specification of 19-21 mm for a pilot mill. The method comprises the following steps: 1) ensuring that the ratio of the length of the steel plate to the length of an effective cooling area is 1.2: (2-5); (2) it is guaranteed that the ratio of the temperature difference value to the total water amount is equal to 2.5-2.8, and meanwhile the requirement that the total water amount of the upper collecting pipe is 4-6 m < 3 > / h smaller than the total water amount of the lower collecting pipe is met; (3) the speed of the controlled cooling rail is calculated according to the needed cooling speed; the calculation basis is that the controlled cooling rail speed = temperature difference / cooling rate; the temperature difference is equal to the final rolling temperature-the final cooling temperature; and (4) it is guaranteed that the spraying width reaches 320 mm when water flow impacts the steel plate, and the height of a nozzle is adjusted by adjusting a motor. According to the method, a front-section centralized and rear-section dispersed cooling mode is adopted, and the cooling control temperature can be more accurately controlled by reasonably setting parameters such as the flow of each group, the roller way speed, the spacing of each group and the height of the laminar cooling nozzles.

The invention discloses a heat treatment method of high-polarization-intensity bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic, which comprises the following steps: arranging an electrode on the surface of a bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic sintered body, and then putting the sintered body into a rapid annealing furnace; the preparation method comprises the following steps: heating to 550-650 DEG C from room temperature at a heating rate of 5-80 DEG C / s, carrying out heat preservation for 45-75 seconds, carrying out first rapid annealing, and cooling to room temperature at a cooling rate of 250-350 DEG C / s, thereby obtaining the bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic. The heat treatment method provided by the invention can rearrange defects in the ceramic, increase domain conversion switches, improve the performance of the ceramic, and improve the performance of the ceramic. Furthermore, the ferroelectric piezoelectric property of the polarized BF-PT-BZT ceramic is greatly improved, and meanwhile, the polarized BF-PT-BZT ceramic has high Curie temperature.

Provided is an annealing facility that contributes to further improvement of magnetic properties by more active control of carbon in steel. An annealing facility includes a heating zone, a soaking zone, and a cooling zone on a conveyance line for a steel strip. The conveyance line is capable of passing a steel strip with a thickness of 2.8 mm or more, the soaking zone has means for maintaining an ambient temperature at 900° C. or higher, the cooling zone has means for supplying a refrigerant to the steel strip and maintaining an average cooling rate of 50° C. / s or higher in a temperature region of 750° C. or lower and 120° C. or higher, and the annealing facility includes removal means for removing the refrigerant on an exit side of the cooling zone.

This invention relates to a wear-resistant, long-life shot peening agent. The shot peening agent, by mass percentage, comprises: C: 0.55-1.0%, Si: 0.25-0.65%, Mn: 5.8-10.5%, Cr: 3.0-7.0%, Ni: 5.6-8.4%, B: 0.0015-0.004%, P: less than 0.05%, S: less than 0.03%, with the balance being Fe and unavoidable impurities. The shot peening agent is prepared by water atomization or gas atomization of molten steel with the above composition. The shot peening agent is then heated to 820-900℃ and held, followed by quenching to room temperature at a quenching cooling rate of V1≤V≤V2. The unit is ℃ / s, where: V1=8.58*ln(103.8-11.27*[B]-5.78*[Mn]-3.16*[Cr]-1.88*[Si]-1.05*[Ni]-2.14*[C])+13.7; V2=37.5+3018*[B]-1.5*[Mn]+5.4*[Cr]-2.1*[Ni]-6.2*[Si]+37.9*[C]; where [C], [Si], [Mn], [Cr], [Ni], and [B] represent the mass percentage content of C, Si, Mn, Cr, Ni, and B, respectively.

The utility model relates to the technical field of crucibles, in particular to a fast-cooling quartz ceramic crucible which comprises a crucible body, the crucible body comprises a crucible bottom with the oval bottom and a crucible barrel connected with the crucible bottom, a sleeve is coaxially arranged outside the crucible barrel, positioning plates are evenly distributed between the crucible barrel and the sleeve, a sealing ring plate is arranged at the bottom of the sleeve, and the sealing ring plate is connected with the crucible barrel. The inner ring of the sealing ring plate and the outer wall of the sleeve are sealed, a crucible flange is arranged at the top of the sleeve, and a closed cooling cavity is formed between the crucible barrel and the sleeve; cooling medium cooling and gas cooling are achieved through gas inlet circulation and liquid inlet circulation, and the cooling speed is flexibly controlled by adjusting the liquid inlet flow and the gas inlet flow. And the cooling rate is adjusted according to different experiment requirements, so that the treatment requirements of different materials are met. Cooling liquid flows around the crucible and continuously circulates to rapidly take away heat. Heat dissipation is accelerated through gas flowing, and the cooling efficiency is improved through the dual cooling mode of the cooling medium and the gas.

The invention relates to the technical field of aluminum alloy material processing, and provides hollow aluminum profile temperature control cooling equipment which comprises a cooling mechanism and a temperature control mechanism. The cooling mechanism comprises a machining table, a cooling tank and a drying assembly installed at the discharging end of the cooling tank, a lifting structure is arranged on the machining table, the cooling tank is installed on the lifting structure, and a plurality of cooling water pipes are erected on the cooling tank at intervals; the temperature control mechanism comprises a coil pipe, a temperature control meter and a temperature measuring instrument, the coil pipe is arranged on the inner wall of the cooling tank, the coil pipe is communicated with a water path and a gas path, the temperature control meter is arranged on the tank wall of the cooling tank, the temperature measuring instrument is arranged in the cooling tank, and the water path and the gas path are communicated with the water path and the gas path respectively. And the temperature control meter is respectively connected with the water path, the gas path and the temperature measuring instrument. The method solves the problems of insufficient temperature control precision and poor cooling rate adaptability, and has the advantages of high temperature control precision, good repeatability and high automation degree.

The invention relates to the technical field of welding processes, in particular to a welding process method for optimizing martensitic stainless steel welding three-zone hardness, which comprises the following steps: welding by adopting gas metal arc welding, and controlling heat input to slow down the cooling rate; dual tempering heat treatment is carried out after welding, specifically, the first tempering temperature is 650-700 DEG C, and after first tempering, standing is carried out for a preset time length, and cooling is carried out to the room temperature; tempering for the second time at the temperature of 580-620 DEG C; wherein the base material is ultra-low carbon martensitic stainless steel, and the welding material is a nickel-molybdenum alloy welding wire matched with the base material. According to the method, gas metal arc welding is adopted for welding, and heat input is controlled to slow down the cooling rate; double tempering heat treatment is carried out after welding, the hardness of a weld zone, a fusion zone and a heat affected zone is eventually homogenized, and synergistic improvement of hardness homogenization and corrosion resistance is achieved.

This invention provides a method for optimizing temperature control in large-volume hydraulic concrete, relating to the field of computer-aided engineering technology. The invention corrects the initial temperature field of the finite element model based on measured temperature values ​​and dynamically determines the candidate range of cooling water inlet temperature according to the current cooling rate, ensuring that each candidate range adapts to the cooling requirements. It achieves an accurate calculation starting point without laboratory testing, shortening the optimization cycle and reducing costs. By pairing candidate inlet water temperature values ​​with thermal resistance values ​​and substituting them into the finite element model to predict the temperature field, it determines the temperature safety margin, temperature difference safety margin, and temperature fluctuation stability index, using these three indices to evaluate the temperature control effect. This avoids the risk of sudden temperature drops caused by a single criterion. By selecting the feasible combination with the smallest deviation between the predicted temperature and the target control temperature as the target temperature control parameter, it achieves refined selection for each time period, ensuring that the internal temperature approaches the preset cooling target and that the cooling process proceeds smoothly.

This utility model discloses a quenching device for compressor processing, relating to the field of quenching technology. It includes a base, a quenching box, and a cooling box. The quenching box is mounted above the base, and the cooling box is also mounted above the base. A connecting plate is mounted below the gantry frame via a hydraulic rod. The quenching box and the cooling box are connected by an overflow pipe. This quenching device for compressor processing utilizes the water level difference between the cooling box and the quenching box to allow the quenching liquid to flow naturally into the cooling box via the overflow pipe. A filter assembly filters impurities. A servo motor drives a stirring mechanism to agitate the liquid in the cooling box, accelerating heat exchange. The dual-box opening design enhances natural heat dissipation. A circulating water pump returns the cooled liquid to the quenching box via a guide frame, forming a closed-loop circulation, increasing the cooling rate, avoiding high-speed heating, reducing surface defects in compressor components after quenching, and lowering subsequent grinding costs.

The present application relates to a kind of low stress polycrystalline silicon ingot preparation method, comprising: S1: the temperature of silicon ingot is controlled at 1150~1250 ℃ under heat preservation;During heat preservation, in the inert atmosphere environment is maintained and the air pressure is controlled as 30~60kPa;S2: according to the equivalent cross-sectional area S of silicon ingot, adjust the opening of heat insulation cage;With 3~6 ℃ / min cooling rate, the temperature of silicon ingot is reduced to 650~750 ℃, and the air pressure around silicon ingot is reduced to 15~25kPa;S3: with 1.5~3 ℃ / min cooling rate, the center temperature of silicon ingot is reduced to 350~450 ℃, and at the same time, the air pressure around silicon ingot is increased to 25~35kPa, heat preservation;S4: after heat preservation, furnace cooling is obtained, and polycrystalline silicon ingot is obtained.The present application can solve the technical problems that the residual stress of polycrystalline silicon ingot prepared by the existing method is relatively large, microcracks are easy to produce, the yield is relatively low, and it is easy to burst.

The invention belongs to the technical field of solid lubrication of materials and space precision motion parts, and provides an annealing treatment method of a solid lubrication film. The method comprises the following steps: heating a solid lubricating film from room temperature to a first temperature at a first heating rate for first heat preservation, wherein the first temperature is 100-250 DEG C; second heating is conducted from the first temperature to a second temperature at a second heating rate, and second heat preservation is conducted, wherein the second temperature ranges from 250 DEG C to 500 DEG C; first cooling is conducted from the second temperature to a third temperature at the first cooling rate, and third heat preservation is conducted, wherein the third temperature ranges from 100 DEG C to 300 DEG C; and second cooling from the third temperature to the room temperature at a second cooling rate. According to the annealing treatment method provided by the invention, the tribological performance of the solid lubricating film is effectively improved.

The invention relates to a mass concrete multi-stage anti-crack construction method, and belongs to the technical field of concrete construction.The mass concrete to-be-poured area is divided into a first peripheral anti-crack area, a second transition slow-release area and a third central heat storage area by establishing a quantifiable partition criterion based on an inner side line of a formwork and the shortest horizontal distance d; anti-cracking reinforced concrete B, transition concrete C and low-hydration-heat concrete A are prepared in a targeted mode, a lap joint transition zone is arranged during pouring to achieve continuous transition of material performance, and meanwhile partition differentiation heat preservation and moisture preservation covering and staged form removal and maintenance in the sequence from the center to the periphery are matched; the temperature reduction rate, shrinkage development and constraint release of different areas form gradient synergy, the problems of temperature cracks and shrinkage cracks caused by fuzzy partition boundaries and space mismatch of materials and maintenance measures in traditional construction are effectively solved, and the stability of crack control, the consistency of construction quality and the structural durability are remarkably improved.

According to the laser splicing welding joint with the high product of strength and elongation and the manufacturing method of the laser splicing welding joint, a joint welding seam, a heat-affected coarse grain area and a heat-affected fine grain area are composed of tempered martensite, transition carbide, reversed austenite and stable nanometer precipitated carbide, the tensile strength of the joint is 1000-1950 MPa, and the ductility of the joint is 14-34%; the method comprises the following steps: i, butt-jointing high-carbon quenched, distributed and tempered steel, and then carrying out laser tailored welding; ii, at least one time of heat treatment is conducted on the splice welding joint, the workpiece is placed in the environment with the temperature T, the heat preservation time t meets the conditions that T is larger than or equal to 100 and smaller than or equal to 525-20 * C-16 * Mn + 12 * Si < 2 + > 10Cr-12Ni + 20Mo + 10Al + 15 * (Nb + V), t is larger than or equal to 15 + 10 * B, and B (mm) is the plate thickness; and iii, after the heat preservation time is up, the splice-welded joint is cooled to the room temperature at the cooling speed not exceeding 100 DEG C / s. By means of the method, the strength and the ductility of the high-carbon quenching-distribution-tempering steel laser splicing welding joint can be greatly improved.