56results about How to "Achieve toughness" patented technology

The invention discloses a powder metallurgy preparation method for a high-strengthening-toughening metal-based composite material and belongs to the field of metal-based composite materials. The method comprises the steps that (1), mixed powder of metal powder and part reinforcing phase is subjected to ball-milling treatment, and ball-milling is stopped before all crystal particles in the metal powder reach ultrafine crystal; (2), the rest reinforcing phase is added to the powder after ball-milling in the step (1), the ball-milling is continued, and the ball-milling is stopped until the reinforcing phase is completely dispersed; (3), after the powder after the ball-milling in the step (2) is treated by powder metallurgy sintering process, then the high-strengthening-toughening metal-basedcomposite material is obtained. According to the powder metallurgy preparation method for the high-strengthening-toughening metal-based composite material, the reinforcing phase is made to be orderlydistributed in a base body by adding the reinforcing phase step by step; crystal particle distribution is adjusted and controlled utilizing the crystal particle refining effect of the reinforcing phase on the base body, a coarse and fine crystal gradient grading structure is formed, thus the strengthening-toughening of materials is realized; and by means of the powder metallurgy preparation methodfor the high-strengthening-toughening metal-based composite material, the process procedure can be simplified, and the strong plasticity of the materials can be improved at the same time.

The invention relates to an easy-welding high-strength large-thickness steel plate preheating-free gas shielded welding process which mainly comprises the following contents that: the large-thickness easy-welding 700MPa-level high-strength steel plate with the thickness of 40-80mm is matched with a high-strength high-toughness welding wire with high deoxidation element content, a 80 percent Ar+20 percent CO2 active mixed gas shielded semi-automatic or automatic welding method is adopted, due to the preheating-free treatment before welding and heating-free treatment after welding, the welding process parameters are strictly controlled, the welding sequence is reasonably arranged, the asbestos cloth coated weldment is used for heat insulation, the defect-free excellent-performance welding joint is obtained, the tensile strength of the joint is not lower than the base metal standard requirement due to mechanical performance detection, the welding line and heat affected zone are good in texture, low-temperature charpy impact absorption work (KV2) is high in surplus amount, and the application environments of the low-temperature environment can be completely met. According to the method, the production process is reduced, the labor conditions of workers are improved, the production cost is saved, and the production efficiency is improved.

The present invention discloses a cement concrete for the wet connection seam of a system sequentially comprising simply-supported bridge and continuous bridge, and a preparation method thereof, wherein the cement concrete comprises cement, river sand, water, a polycarboxylic acid-based efficient water reducer, rice hull ash, apatite, sericite, sepiolite, a sodium polyacrylate high water absorption resin, talc powder, nanometer calcium carbonate, polyethylene fibers and polyester fibers, and with the synergistic effect among the mineral components such as the apatite, the sericite and the sepiolite and the two fibers, the toughening can be achieved, the impact resistance and the extension ability of the concrete can be improved, and the problems that the wet connection seam concrete is damaged and the bridge surface cracks can be effectively solved. According to the present invention, the cement concrete has advantages of high compressive strength, good toughness, impact resistance, permeation resistance, self-leveling, and the like.

The invention belongs to the field of titanium alloy materials, and discloses a double-scale structure titanium alloy based on in-situ whisker strengthening and toughening and a preparation method and application of the double-scale structure titanium alloy. The titanium alloy comprises elements including, by atomic percent, 58%-70% of Ti, 9%-16% of Nb, 4%-9% of Cu, 4%-9% of Ni, 2%-8% of Al and 0.5%-3% of B. According to a microstructure of the titanium alloy, part of ultra-fine grain fcc MTi2 is distributed along a micron grain bcc beta-Ti base body grain boundary in a long-strip-shaped manner, part of ultra-fine grain fcc MTi2 is distributed in the micron grain bcc beta-Ti in a long-strip-shaped manner, ultra-fine grain in-situ TiB whiskers are distributed in the ultra-fine grain fcc MTi2 and a micron grain bcc beta-Ti of the grain boundary, and M is equal to Cu and Ni. The fine-needle-shaped in-situ TiB whiskers are introduced in a double-scale structure of an ultra-fine grain second phase and a micron equiaxed grain base body, and further strengthening and toughening of the material are achieved.

The invention provides a multilayer metal coupling deformation rolling combined method and device. The device comprises a compound blank heating furnace, a high-pressure water descaling machine, a four-roller reversible rolling mill, a front reeling holding furnace, a rear reeling holding furnace, a front board criss cross bending deformation unit, a rear board criss cross bending deformation unit, a laminar cooling unit and a finished product reeling machine. According to the method, the reeling heating furnaces are equipped in front of and in rear of the single-frame four-roller reversible rolling mill, and the tension bending units are arranged between the front reeling furnace and the rear reeling furnace, the tension bending rollers are flower rollers of which the surfaces are of a convex and concave structure, three flower rollers form a reverse bending deformation unit, and a convex-concave structure of a front roller surface and a convex-concave structure of a rear roller surface are arranged in a staggered mode, so that a temperature controlling reeling coupling deformation rolling combined mechanism used for applying tension and achieving board criss cross bending deformation is formed, residual stress of a compound interface is remarkably reduced, and board shape quality is ensured; and meanwhile, the bonding strength and binding rate of the compound interfaces are greatly improved, the structure performance and comprehensive mechanical performance of composite boards are improved, and the production efficiency and yield are remarkably improved.

A machining technology for the aged 18(Ni)-series non-Co martensite steel with high strength and toughness includes hot working, cold working by direct cold rolling or machining without solution treatment, ageing at 400-600 deg.C for 0.5-3 hrs, and air or water cooling. Its advantages are short period and simplified heat treatment.

The invention discloses a method for improving the room temperature plasticity of refractory high-entropy alloy, and relates to the field of metal materials and preparation thereof. According to the specific scheme, the method includes the steps that 1) all component materials required for smelting the alloy are obtained and purified; 2) the materials obtained in the step 1) are placed in a non-consumable vacuum arc furnace, and hydrogen and argon are introduced after vacuumizing; and 3) smelting is carried out to obtain a room temperature plastic alloy material. The room temperature compression plasticity of the alloy obtained after melt hydrogenation is remarkably improved, the yield strength of the alloy is not reduced, and the microstructure is refined. The method solves the problems of poor room temperature plasticity and poor cold deformation capability of the refractory high-entropy alloy, improves the cold state plastic deformation limit of the alloy, realizes strengthening andtoughening of the refractory high-entropy alloy, and plays an important role in promoting engineering application of the alloy.

According to the laser additive manufacturing method for synergistically improving the surface precision and strength of the titanium alloy, the forming structure is adjustable, the surface is smoothand clean, the surface is self-strengthened, and extra surface treatment and other procedures are not needed. The method comprises the following steps: uniformly and continuously pre-paving Ti6Al4V alloy powder on a forming cabin substrate of laser additive manufacturing equipment, and printing and forming layer by layer to obtain a Ti6Al4V alloy test piece; when each layer is printed and formed,using laser beams to adjacently scan line by line to form an internal solid plane, after forming the internal solid plane, performing laser scanning of a contour along the edge of the internal solid plane to form an external contour, and finish forming of the printing layer; repeating the forming process of the printing layers until laser additive manufacturing forming of the Ti6Al4V alloy test piece is completed, wherein the laser power for printing internal solid plane is not less than the laser power for printing the external contour, and the scanning speed for printing the internal solid plane is not greater than the scanning speed of the printing external contour.

The invention discloses a method for preparing a titanium material through powder metallurgy with a modifier, relates to a method for preparing the titanium material through powder metallurgy and aimsto solve the problems that a titanium material prepared by using a conventional powder metallurgy material is large in texture and degraded in plasticity as textures cannot be controlled. The methodcomprises the following steps: I, performing mechanical powder stirring and mixing, namely mechanically mixing modifier powder, pure titanium and titanium alloy powder by using a stirring and mixing machine so as to obtain composite powder; II, performing sintering, namely sintering the composite powder in a vacuumed sealed container, and naturally cooling to a room temperature, thereby obtaininga modified powder metallurgy titanium material with controllable textures.

The invention discloses a preparation method of a cell structure gradient tungsten alloy material. The preparation method comprises the following steps that high-tungsten base prealloy powder and low-tungsten base prealloy powder are obtained through prealloying treatment in advance, after the high-tungsten base prealloy powder is atomized and pelletized and is uniformly mixed with the low-tungsten base prealloy powder, compression forming is carried out in a cold isostatic pressing machine, two-step sintering is carried out in a high-temperature vacuum tube type furnace, and finally the cellstructure gradient tungsten alloy material is obtained.

The invention discloses a method for preparing a composite antiwear roller, which is characterized by comprising the following steps: alloy dust core bars are bound into bundles and arranged in a roller casting mould cavity, and the volume of the alloy dust core bars accounts for 20 to 60 percent of the total volume of the antiwear roller; molten matrix metal is cast into the casting mould cavity, the alloy dust core bars are melted and dissolved under the heat effect of the matrix metal, a great number of alloy elements and the molten matrix metal generate metallurgical combination reaction so as to generate a highly dispersed alloy structure on the original position; and finally the alloy structure is cooled and solidified, and the bar-shaped hard phase is metallurgically and transitionally combined into a whole with the matrix metal, thereby preparing the composite antiwear roller which takes the high-strength and high-ductility metal as the matrix and contains a certain number of metallurgically combined bar-shaped hard points. The composite antiwear roller has high strength and high ductility of the matrix metal and high hardness and high wear resistance of the hard phase, can simultaneously bear high pressure and strong wear, and has the characteristics of long service life, low price and so on.

The invention relates to the field of preparation of novel metal materials, in particular to a preparation method of a light titanium-rich Ti-Zr-Nb-Al series refractory high-entropy alloy-based composite material. The invention aims to solve the problems of high density, poor plasticity and incapability of large-size preparation of an existing refractory high-entropy alloy. The method comprises the steps that firstly, raw materials are weighed according to the proportion, the raw materials are mixed and smelted into metal ingots, powder is prepared through a high-energy-density plasma rotating electrode atomization technology, and matrix powder is obtained; 2, additional reinforcement powder is weighed; 3, the matrix powder and the additional reinforcement powder are mixed, and low-energy ball milling is conducted in a high-purity argon atmosphere to obtain mixed powder; and 4, the mixed powder is subjected to vacuum hot press sintering, a compact block material, namely the light titanium-rich Ti-Zr-Nb-Al series refractory high-entropy alloy-based composite material, is obtained. The method is used for high-temperature structural members.

The invention provides a precipitation strengthening type medium-entropy alloy suitable for laser additive manufacturing and a preparation method thereof, the precipitation strengthening type medium-entropy alloy is NiaCobCrcAldMe, M is one or more elements of Ti, Ta, Nb and Mo, a, b, c, d and e respectively represent the molar percentage corresponding to each element, b is 20%-40%, c is 20%-25%, and dgt is 1%-2%; 1%, egt; 0, d + ilt; a + b + c + d + e = 100%. The precipitation strengthening type medium-entropy alloy is prepared through the selective laser melting forming technology or the laser three-dimensional forming technology, and preparation of the novel precipitation strengthening type medium-entropy alloy which is high in compactness, free of cracks and excellent in comprehensive mechanical property is achieved.

The invention discloses a preparation method of a multi-layer large-gradient hard alloy material easy to weld. The preparation method of the multi-layer large-gradient hard alloy material easy to weldcomprises the steps that pre-alloying is conducted to obtain WC-Co pre-alloyed powder, WC-Ni pre-alloyed powder and WC-Fe pre-alloyed powder; then a forming agent is added to the WC-Co pre-alloyed powder, the WC-Ni pre-alloyed powder and the WC-Fe pre-alloyed powder to conduct compression molding; an obtained green body material is arrayed according to additive components, and nickel powder is spread between different layers; and the green body material is conveyed into a rapid hot-pressing sintering furnace to be sintered, so that the multi-layer large-gradient hard alloy material easy to weld is finally obtained.

The invention provides a carbon-based composite film and a preparation method thereof, and belongs to the field of surface engineering. According to the carbon-based composite film and the preparationmethod thereof, a carbon target and a metal carbide target serve as a sputtering target material, based on closed field unbalanced magnetron sputtering plasma space distribution characteristics and the rule of influence of the rotation speed of a sample rotating stand on a film structure, only through cyclic control over high-speed and low-speed rotation of the sample rotating stand, and the double-structure carbon-based composite film comprising both a nanolayer structure and a nano composite structure is spontaneously formed in the deposition process; the carbon target and the metal carbidetarget are oppositely arranged in a vacuum cavity, when the rotation speed of the rotating stand is high, a composite film with the nano composite structure is deposited out, and when the rotation speed of the rotating stand is low, a composite film with a nano multi-layer structure is deposited out; and the size of nanocrystalline in the nano composite structure and the modulation period of thenano multi-layer structure can be achieved through adjusting of the rotation speed of the rotating stand, and the thickness of a nano composite structure layer and the thickness of a nano multi-layerstructure layer can be achieved by controlling the time for cyclic adjustment of the rotation speed of the sample rotating stand.

The invention discloses a preparation method of a complex-phase co-strengthening hard alloy material. According to the method, firstly, pre-alloying treatment is carried out to obtain tungsten carbidebase pre-alloying powder and titanium carbonitride base pre-allying powder, the two kinds of powder are mixed with cobalt powder uniformly, the powder is subjected to secondary atomizing, drying andpelletizing, then pressed and formed in a cold pressing machine, and finally sintered in a high-temperature vacuum pipe type furnace, and finally, the complex-phase co-strengthening hard alloy material is obtained.

The invention discloses welding wire steel for manual argon arc welding. The welding wire steel comprises, by mass, 0.0001%-0.08% of C, 0.80%-1.50% of Mn, 0.70%-0.95% of Si, 0.0001%-0.010% of S, 0.0001%-0.020% of P, 0.0001%-0.40% of Cr, 0.10-0.30% of Mo, 0.0001%-0.40% of Ni, and the balance Fe and inevitable impurity elements. The welding wire steel is low in cost, high in welding seam strength and toughness, stable in quality and good in welding performance, and can meet the use requirements of welding wire manufacturers. According to the welding wire steel, the welding performance of the low-alloy high-strength welding wire is improved in a limited mode while the high-strength of weld metal is ensured, the occurrence of cold cracks is controlled, the splashing rate is small, and the welding requirements of the low-alloy high-strength steel are met.

The invention discloses a self-repairing method of firmware in an intelligent memory device. The firmware is written into two different blocks in the intelligent memory device, and mutually remembersthe position information of opposite sides; when the data of one side is corrupted, the firmware with wrong data is repaired by utilizing the firmware with correct data. The wrong firmware can be corrected, and the normal data of the wrong firmware is recovered.

The invention provides a preparation method for a dual model-structure graphene-reinforced aluminum matrix composite and relates to a preparation method for an aluminum matrix composite. By means of the preparation method, the problems that graphene is easy to agglomerate when the graphene-reinforced aluminum matrix composite is prepared, and that strength-tenacity inversion exists in the preparedcomposite are solved. The preparation method comprises the steps that an ascorbic acid solution is added to an oxidized graphene dispersion liquid, and oxidized graphene colloid is acquired; vacuum freeze-drying is conducted, and a three-dimensional graphene framework is acquired; after the three-dimensional graphene framework and aluminum metal powder are mixed, ball milling is conducted, and mixed powder is acquired; and then pressure infiltration ingot preparation, heat deformation treatment and heat treatment are conducted sequentially. By means of the prepared three-dimensional grapheneframework structure, the phenomenon of agglomeration can be avoided; and through a dual-model structure of mixing of coarse grains and fine grains, the material strength is elevated, and in the meantime, the material tenacity can also be guaranteed. The preparation method for the dual model-structure graphene-reinforced aluminum matrix composite is applicable to preparation of graphene-reinforcedaluminum matrix composites.