37results about How to "No macro defects" patented technology

The invention relates to a method for growing a large size Ta2O5 single crystal by using a floating zone method, and belongs to the field of crystal growth. The method comprises the following steps: carrying out ball milling and drying for a Ta2O5 powder material; placing the treated Ta2O5 powder material in a rubber tube, and carrying out isostatic pressing for the material to prepare a biscuit rod; carrying out sintering for the biscuit rod to obtain a polycrystalline rod; adopting the biscuit rod or the polycrystalline rod as the material rod, and adopting the polycrystalline or the Ta2O5 single crystal as the seed crystal, wherein the seed crystal and the material rod form a straight line in a vertical direction, and the contact point and a halogen lamp are at the same horizontal line; heating the material rod and the seed crystal until the material rod and the seed crystal are molten, wherein the heating rate is 30-60 DEG C per minute; adjusting the rotation speeds and the rotation directions of the material rod and the seed crystal, then carrying out inoculation; adopting the movement of a focusing lens or the up and down movement of the rod to enable the molten zone to be far away from the focusing point, enable the temperature of the molten zone to be decreased to realize the crystallization, wherein the crystal growth rate is 10-60 mm / h; cooling the grown crystal to the room temperature. With the method provided by the present invention, the growth period is short; the preparation efficiency is high; the Ta2O5 single crystal can be rapidly grown, wherein the grownTa2O5 single crystal has characteristics of size in centimeter magnitude, no macroscopic defect and high quality.

The invention provides a laser-arc hybrid welding method for a special aluminum alloy thin edge structure. The method comprises the steps of (1) performing alkali washing on a structure to be welded by a NaOH solution to remove an oxidation film, performing acid washing on the structure to be welded by a HNO3 solution, then cleaning the structure to be welded by clean water, and drying the structure to be welded by compressed air; (2) welding the structure to be welded by adopting a laser guiding arc mode, wherein the welding speed is 1-3mm / min, the laser power is 500-2500W, the TIG arc current is 100-150A, the included angle between the TIG arc angle and the normal line is 35 degrees, the TIG arc height is 2-4mm, the laser arc heat source interval is 2-4mm, and the shielding gas is argon with the flow of 15-25L / min; and (3) cleaning the faces of the welding seams by using a steel brush. The stability in the welding process and the face quality of the welding seams are improved by adopting the laser-arc hybrid welding and optimized welding process, the assembly gap demand before welding is reduced and the structural deformation after welding is reduced.

The invention provides reactive powder concrete and preparing method and purpose thereof. The reactive powder concrete is prepared from 400-1000 parts of cement, 100-500 parts of modified superfines, 50-200 parts of modified steel fiber, 900-1300 parts of quartz sand, 100-220 parts of quartz powder, 10-30 parts of admixture, and 100-250 parts of water. According to characteristics of inorganic whisker which it has no macroscopic defect, its crystal intensity approximates theoretical value of intact crystal, and mechanical strength is equivalent to force of neighboring atoms, the invention, by adding whisker, improves RPC-related properties with compressive strength and rupture strength up to construction requirements; by modification of steel fiber, it improves wrapping of slurry on steel fiber, enhances fracture energy and strength increase of RPC product and reduces interface microcrack.

The invention relates to a laser welding process, and particularly relates to a laser welding process for welding nickel-plated copper with the thickness of 200 microns by employing a single-mode laser. The laser welding process is characterized in that a welding clamp is a copper cup pressing mechanism and presses the periphery of a welding part of a test piece, and shielding gas is blown out inthe welding process to protect the welding part; an experimental material is placed on a workbench, a copper cup is controlled to move to the welding part through a PLC program and is pressed, and anair blowing instruction is given through a PLC in the welding process; the laser is the single-mode laser, a galvanometer head is adopted for welding, the defocusing amount is +2mm, and the laser power, the welding speed and the welding path are adjusted through a laser control system; and employed process parameters of the laser welding are as follows: the laser power is 900w-1200w, the welding speed is 170mm / s-240mm / s, the welding path is a hyperbola, and the defocusing amount is + 2mm. In the welding process, various welding process parameters are adjusted, the process environment is improved, it is guaranteed that welds are well formed, macroscopic defects are avoided, all performances meet the production and application standards, the welding problem generated when the nickel-plated copper is applied to the production of the positive electrode of the battery tab is solved, and the quality of the welding joints is guaranteed.

The invention discloses a 1800MPa-grade ultrahigh-strength hot-formed steel plate resistance spot welding technology, and relates to a high-strength steel plate spot welding technology. According to the technology, two pieces of ultrahigh-strength hot-formed steel are lapped together and clamped by a clamp, a resistance spot welding robot teaching panel is used, the position of a path adjusting electrode is set, a welding part is positioned at the central point of the lapped part, a welding instruction is added to the teaching panel, the welding pressure is changed, after welding parameters are adjusted through a welding machine, the welding instruction is input to complete the welding process once, and a resistance spot welding joint is formed. The manufacturing and processing technology capable of perfecting the ultrahigh-strength hot-formed steel plate is provided, and the ultrahigh-strength hot-formed steel plate can be favorably combined together in production and manufacturing, so that the comprehensive performance of the product is remarkably improved.

A method for crucible-free rapid growth of centimeter magnitude Ti:Ta2O5 crystals belongs to the field of Ti:Ta2O5 crystal growth. Mixing, ball-milling and burning are carried out on TiO2 and Ta2O5 powder to press rob-shaped polycrystalline rods; the polycrystalline rods respectively serve as charge rods and seed crystals to be installed in a single crystal furnace, a heating rate is set, crystal growth is carried out, cooling time is set, the crystals after growing are cooled to a room temperature. The method is a crucible-free growth technique which can rapidly grow centimeter magnitudes, is free of macroscopic defect and has high-quality Ti:Ta2O5 crystals.

The invention discloses a nano multilayered silicon nitride ceramic coating and a preparation method and application thereof. The coating comprises a multilayered structure which is formed by direct-current reaction sputtering silicon nitride layers and radiofrequency sputtering silicon nitride layers which are alternately overlapped. The preparation method of the coating comprises the following step: depositing on a base material by taking a monocrystalline silicon target and / or a silicon nitride target as a cathode and taking inert gas and nitrogen as working gas and by a direct-current reaction sputtering technology and a radiofrequency sputtering technology to form the nano multilayered silicon nitride ceramic coating. The nano multilayered silicon nitride ceramic coating comprises direct-current reaction sputtering silicon nitride layers and radiofrequency sputtering silicon nitride layers which are alternately stacked. The nano multilayered silicon nitride ceramic coating is combined to a porous ceramic base material and the like well, has the advantages of compact structure, controlled thickness, high hardness, low internal stress, zero macroscopic defects and the like, andcan be applied to multiple fields of precise filtering and separation of various media, high-temperature wave transmitting / wave absorbing, electrolysis diaphragms and the like.

The invention discloses a crucibleless growth method of sapphire crystals in different atmospheres, and belongs to the field of sapphire crystal growth. The method comprises the following steps: a polycrystalline rod is prepared by using high-purity raw materials of Al2O3, FeTiO3 and Fe2O3; the polycrystalline rod is put into a crystal growth furnace, and is sleeved by a quartz tube; oxygen gas or argon gas is led to the quartz tube, and a gas valve is closed when the pressure reaches a certain value; the temperature rises for 0.5 to 1 hour until the material rod and seed crystals are melted; a crystal growth speed is set for crystal growth; the grown crystals are cooled to reach the room temperature; and the gas valve is opened, and the gas is released to the normal atmospheric pressure. The sapphire crystals grown through the method have large sizes, evener color and better quality, and avoid macroscopic defects.

The invention discloses a preparation method of a special wear resistant plastic ramming mass for a pure low-temperature cogeneration technology. The method comprises the following steps of: (1) blending raw materials, wherein the raw materials comprise a ramming mass matrix, high-carbon asphalt powder, a surface treating agent and a composite binder, and the ramming mass matrix comprises emery, spheroidal graphite powder, Al2O3 powder, SiO2 micro powder, blue crystal powder and chromium mineral powder; (2) carrying out first-layer mixing on the components in the ramming mass matrix except the Al2O3 powder and the SiO2 micro powder with the high-carbon asphalt powder, then adding the SiO2 micro powder and silicon-aluminum oxide powder which are treated by using the surface treating agent to carry out second-layer mixing, and next, adding the composite binder to carry out a third-layer mixing; and (3) carrying out toughening treatment on the ramming mass by adopting a metal hexsteel, and then carrying out the toughening treatment by blending with steel fibers in the ramming mass. The ramming mass prepared by using the method has wear resistance, long service life and high heat utilization ratio.

The invention provides reactive powder concrete and preparing method and purpose thereof. The reactive powder concrete is prepared from 400-1000 parts of cement, 100-500 parts of modified superfines, 50-200 parts of modified steel fiber, 900-1300 parts of quartz sand, 100-220 parts of quartz powder, 10-30 parts of admixture, and 100-250 parts of water. According to characteristics of inorganic whisker which it has no macroscopic defect, its crystal intensity approximates theoretical value of intact crystal, and mechanical strength is equivalent to force of neighboring atoms, the invention, by adding whisker, improves RPC-related properties with compressive strength and rupture strength up to construction requirements; by modification of steel fiber, it improves wrapping of slurry on steel fiber, enhances fracture energy and strength increase of RPC product and reduces interface microcrack.

The invention relates to a 3D printing cement-based material used for underwater construction and a preparation method of the 3D printing cement-based material. The 3D printing cement-based material is prepared from the following components and raw materials by weight: 100 parts of cement, 0-60 parts of mineral powder, 0-30 parts of fly ash, 0-20 parts of silica fume, 0.1-3 parts of a water reducing agent, 0.1-5 parts of an anti-dispersion agent, 0.2-5 parts of a binder, 0.005-0.5 part of an air entraining agent, 0.01-25 parts of a plastic retaining agent, 0-0.5 part of starch ether, 0.01-0.5 part of a thickening time control agent, 0.1-10 parts of an expanding agent, 0.1-10 parts of an early strength agent, 0.01-0.5 part of fiber, 50-300 parts of fine aggregate, and 0-400 parts of coarse aggregate. Compared with the prior art, the 3D printing cement-based material, when used in the underwater printing construction, has the excellent advantages of constructability, dispersion resistance and durability and has an excellent bulk property in water, a printed building does not collapse, and the mechanical property is excellent.

The invention relates to a method for preparing surface composite sintering machine grate bars, and belongs to the field of metal matrix composite materials. The present invention comprises SiC powder, aluminum oxide powder, ferrochrome powder, adds polyvinyl alcohol aqueous solution and is mixed with alloy powder coating, then it is coated on the working surface of sintering machine grate bar foam plastic model or the mold cavity of sand mold is corresponding to on the molded wall of the work surface. The high chromium cast iron or ferritic nodular cast iron melt is smelted in an electric furnace and cast, so as to prepare the surface composite sintering machine grate. After testing: the surface composite layer containing Al 2O 3+SiC reinforced particles is metallurgically bonded to the cast iron matrix, and the composite layer is dense without obvious macro defects, with a thickness of more than 5mm and a hardness of HRC45-60.

The invention discloses a large-lead nut turning device, which comprises a cutter base, a cutter bar, a lathe tool and a guide sleeve, wherein the cutter base comprises a connecting structure connected with a lathe cutter saddle; the cutter bar is fixedly arranged on the cutter base for extending into a prefabricated hole of the nut to be turned; the lathe tool is fixedly arranged on the part of the cutter bar for extending into the nut; and the guide sleeve is connected with the cutter bar for forming shaft fitting with the prefabricated hole of the nut to form auxiliary supporting. The large-lead nut turning device is high in processing precision and good in processing consistence.

A argon arc welding process for 1800MPa ultra-high-strength hot-formed steel sheets. The method is to butt together two ultra-high-strength hot-formed steels with clean surfaces and no foreign matter, and tighten them with clamps to ensure that the plates will not be displaced during the welding process. . Set the path program of the welding robot so that the welding torch moves along the weld. Adjust the relevant parameters of the argon arc welding machine to weld the plate. The invention provides a manufacturing and processing technology capable of perfecting the ultra-high-strength hot-formed steel sheet. Using the invention, the ultra-high-strength hot-formed steel sheet can be advantageously combined in production, thereby significantly improving the comprehensive performance of the product.

The invention provides a laser-arc hybrid welding method for a special aluminum alloy thin edge structure. The method comprises the steps of (1) performing alkali washing on a structure to be welded by a NaOH solution to remove an oxidation film, performing acid washing on the structure to be welded by a HNO3 solution, then cleaning the structure to be welded by clean water, and drying the structure to be welded by compressed air; (2) welding the structure to be welded by adopting a laser guiding arc mode, wherein the welding speed is 1-3mm / min, the laser power is 500-2500W, the TIG arc current is 100-150A, the included angle between the TIG arc angle and the normal line is 35 degrees, the TIG arc height is 2-4mm, the laser arc heat source interval is 2-4mm, and the shielding gas is argon with the flow of 15-25L / min; and (3) cleaning the faces of the welding seams by using a steel brush. The stability in the welding process and the face quality of the welding seams are improved by adopting the laser-arc hybrid welding and optimized welding process, the assembly gap demand before welding is reduced and the structural deformation after welding is reduced.

The invention relates to a method for growing a large size Ta2O5 single crystal by using a floating zone method, and belongs to the field of crystal growth. The method comprises the following steps: carrying out ball milling and drying for a Ta2O5 powder material; placing the treated Ta2O5 powder material in a rubber tube, and carrying out isostatic pressing for the material to prepare a biscuit rod; carrying out sintering for the biscuit rod to obtain a polycrystalline rod; adopting the biscuit rod or the polycrystalline rod as the material rod, and adopting the polycrystalline or the Ta2O5 single crystal as the seed crystal, wherein the seed crystal and the material rod form a straight line in a vertical direction, and the contact point and a halogen lamp are at the same horizontal line; heating the material rod and the seed crystal until the material rod and the seed crystal are molten, wherein the heating rate is 30-60 DEG C per minute; adjusting the rotation speeds and the rotation directions of the material rod and the seed crystal, then carrying out inoculation; adopting the movement of a focusing lens or the up and down movement of the rod to enable the molten zone to be far away from the focusing point, enable the temperature of the molten zone to be decreased to realize the crystallization, wherein the crystal growth rate is 10-60 mm / h; cooling the grown crystal to the room temperature. With the method provided by the present invention, the growth period is short; the preparation efficiency is high; the Ta2O5 single crystal can be rapidly grown, wherein the grownTa2O5 single crystal has characteristics of size in centimeter magnitude, no macroscopic defect and high quality.

The invention relates to a stage heating and extrusion controlling device for powder superalloy members and a using method. According to the using method, with the help of the deformation temperatureand pressure of stage change, the low-temperature and low-pressure curing and high-temperature and high-pressure controlling of powder materials at a time are realized. The method comprises the stepsthat firstly, powder is preliminarily cured under the conditions of lower temperature (no more than 700 DEG C) and lower pressure (no more than 500 MPa); then, the superalloy powder is completely densified by increasing the temperature (no more than 1000 DEG C) and combining plastic deformation parameters such as low extrusion ratio (no more than 2:1) and deformation speed, and a powder superalloyingot with certain deformation is obtained; and a microstructure with the grain size being 7-13 levels can be obtained by further increasing the temperature (no more than 1100 DEG C) and combining plastic deformation parameters such as larger extrusion ratio ((4:1)-(9:1)) and deformation speed. The integration of solidification-control of the powder superalloy members is achieved, the technological process is simplified, the development cycle is shortened, the material utilization rate is improved, and the manufacturing cost of the members is reduced.

The invention discloses a welding technology for an aluminum alloy network cabinet, and belongs to the technical field of welding. The welding technology includes the steps of 1, material preparing, 2, pre-welding cleaning, 3, pre-welding preheating, 4, welding work, 5, post-welding cleaning and the like. A welding wire comprises, by mass, 7% of Mg, 0.5% of Mn, 0.54% of Ti, 0.7% of Zn, 0.8% of Cr, 0.6% of Zr, 2% of Sc, 0.4% of Fe, 0.45% of Si, 0.74% of Li, 1% of B and the balance Al. Weld joints, processed with the welding technology, of the network cabinet are attractive in appearance, the welding process is stable, and no macro defect exists on the surfaces of the weld joints; as the material components of the welding wire are optimized, the welding wire has the excellent welding technological performance, and a welded connector is high in strength and good in corrosion resistance; as the welding technology is optimized, surface defects are avoided, and welding deformation is reduced; the welding efficiency is high, and the welding speed is higher than 1 mm / min.