34results about How to "Strong pinning effect" patented technology

A method and apparatus for fabrication of objects retaining nano-scale characteristics. A composition is provided comprising grain growth inhibitor particles in solution with a binding agent in a molten phase. An electric field and a magnetic field are generated with a combined extraction electrode. The composition is electrosprayed from a nozzle with the electric field to form a stream of droplets. The electric field drives the droplets toward a moving stage holding an object comprising successive deposition layers. The magnetic field limits dispersion of the stream of droplets. The stage is moved laterally as the stream of droplets impacts the object to form a current deposition layer of the object. The stage is moved vertically as necessary to maintain a target stand-off distance between the nozzle and a previous deposition layer of the object, based on profile data of the previous deposition layer.

The invention discloses a method for preparing silicon oxide nanofiber. The method comprises the following steps of mixing silica sol with a nitrate solution, performing ultrasonic dispersion on the solution, adding ethylenediamine after the dissolution of the nitrate solution, and stirring uniformly to obtain a mixed solution; putting the mixed solution into a stainless steel reaction kettle with a polytetrafluoroethylene liner, standing the reaction kettle in a high-temperature baking oven after the closing of the reaction kettle, and performing a hydrothermal reaction; taking out the reaction kettle and cooling the reaction kettle to room temperature after the completion of the reaction, collecting precipitates in the reaction kettle, and washing the precipitates to obtain a silicon oxide nanofiber crude product; adding the silicon oxide nanofiber crude product into a hydrochloric acid solution, stirring in a thermostatic water bath, removing impurity components from the silicon oxide nanofiber crude product, and performing centrifugal separation to obtain a silicon oxide nanofiber finished product. The method disclosed by the invention has the advantages that not only can the high energy consumption in a nanofiber preparation process through a traditional chemical vapor deposition and thermal evaporation technology be avoided, but also the production is easily expanded by utilization of a hydrothermal synthesis technology.

The invention discloses a graphite material with a SiC doped layer and a preparation method of the graphite material. The preparation method of the graphite material with the SiC doped layer comprises the following step: by taking mixed powder of silicon-containing powder and boron nitride as a silicon source, performing liquid-phase siliconing sintering on a graphite material, thereby obtaining the graphite material with the SiC doped layer. The graphite material with the SiC doped layer prepared by using the method comprises a graphite substrate and the SiC doped layer on the surface of the graphite substrate, the SiC doped layer is well combined with the graphite substrate without thermal mismatch, the graphite material is good in oxidation and corrosion resistance and relatively low in cost, and a small amount of silicon is adhered to the surface of the graphite material.

The invention provides a preparing method of a nanocrystal Sm<2>Co<17>/Co double-phase composite permanent magnetic alloy, and belongs to the technical field of double-phase composite permanent magnetic alloys. The method includes smelting a pure Sm block, a Co block and an elementary substance of an added element under the protection of argon to obtain a multi-component parent phase alloy; allowing phases and component distribution of the parent phase alloy to be uniform by a plurality of times of remelting and homogenizing annealing; preparing the parent phase alloy into amorphous powder by utilization of high-energy ball milling under the protection of an inert gas; preparing the amorphous powder into an initial nanocrystal alloy block which is a metastable phase alloy by spark plasma sintering; and preparing the nanocrystal Sm<2>Co<17>/Co double-phase composite permanent magnetic alloy by a thermal treatment process. The method has advantages of uniform crystal grain size distribution, controllable crystal grain size, controllable phase composition, controllable phase stability, and the like.

The invention relates to a method for predicting the grain size of a micro-alloy steel welding coarse grained region and belongs to the field of physical measurement. The method comprises the steps that firstly, through heat simulation, information of the original austenite grain size of the micro-alloy steel welding coarse grained region under three or more different kinds of heat input is obtained; secondly, the grain growth dynamics formula which is shown in the description is set, wherein M0 and PZ are unknown constants, other parameters are known parameters, corresponding reasonable values are obtained by looking up literature, then the values of the original austenite grain size of the coarse grained region under three different kinds of heat input and the grain growth dynamics formula are fitted (through numerical integration and a finite difference method), and the values of M0 and PZ are obtained through an optimal fitting result; finally, through the grain growth dynamics formula and the fitted values of M0 and PZ, the grain size of the micro-alloy steel welding coarse grained region under different kinds of welding heat input is calculated, and the grain size of the micro-alloy steel welding coarse grained region is predicted. According to the method, the fitting and calculation process is simplified, and importance basis is provided for controlling the grain size ofthe micro-alloy steel welding coarse grained region.

The invention discloses an electric heating wire formulation and an electric heating wire preparation process. The electric heating wire formulation comprises, by mass, 30-50% of Cr, 30-50% of Ni, 1-5% of W, 1-3% of Mo, 5-10% of Ai, 1-3% of Si, 0.3-3% of Y2O3 composite oxide and the balance Fe. Corresponding raw material powder is subjected to mechanical alloying, drying, pressing, sintering, forging, hot rolling, bright annealing and surface preoxidation film treatment, nano oxides high in distribution density and small in size exist in a matrix and have a remarkable pinning effect on dislocation motion of alloy under a high-temperature condition, creep resistance of an electric heating wire at a high temperature is improved, the service life of the electric heating wire is longer than that of an existing electric heating wire by ten times or more, the utilization temperature reaches 1400 DEG C, and usability of the electric heating wire is greatly improved.

The invention relates to a ferritic steel plate with a nanaoscale spherical cementite enhancing function and a preparation method of the ferritic steel plate. The steel plate is prepared from, by mass percent, 0.95%-1.05% of Cr, 0.95%-1.00% of Mo, 0.68%-0.75% of Mn, 0.57%-0.62% of Ni, 0.37%-0.52% of Al, 0.39%-0.45% of C and the balance Fe and inevitable impurities. The microstructure of the ferritic steel plate is equiaxed ferritic grains, nanaoscale spherical cementite is dispersed and distributed in the ferritic grain boundary region, the diameter of the grains ranges from 0.4 micrometer to 3 micrometers, and the size of the nanaoscale spherical cementite ranges from 70 nm to 150 nm; and the thickness of the ferritic steel plate ranges from 1.4 mm to 2.0 mm. The preparation method comprises the steps that 1, smelting is carried out under gas shield; 2, hot rolling is carried out after solid solution treatment; 3, warm rolling is carried out after heat treatment; and 4, annealing is carried out to obtain the finished steel plate. According to the steel plate, the yield strength and tensile strength of the steel plate are improved, and the good machining performance and plastic deformation capacity are achieved. The preparation method is simple, and industrial production can be achieved.

The invention discloses a titanium microalloying high-silicon-content aluminum alloy and a preparing method thereof. The aluminum alloy comprises, by mass percent, 11.0%-14.0% of Si, 0.2%-0.7% of Mg, smaller than or equal to 0.15% of Fe, 0.015%-0.04% of Sr, 0.01%-0.03% of B, 0.05%-0.25% of Ti and the balance aluminum. The preparing method includes the steps that an aluminum-silicon intermediate alloy, a magnesium element, a silicon element and a titanium element are heated and melted, hexachloroethane is added for refining when melt is heated to 720 DEG C to 740 DEG C, Al-Sr and Al-B intermediate alloys are added for metamorphism treatment and grain refining treatment after standing is conducted, heat preservation is conducted for 30 min, vacuum standing is conducted for 30 min to 60 min, the mixture is heated to 710 DEG C to 730 DEG C and poured into a die, and a cast ingot is obtained; annealing is conducted for 3 h to 6 h under the temperature ranging from 520 DEG C to 540 DEG C; and hot extrusion or hot rolling deformation is conducted under the temperature ranging from 400 DEG C to 500 DEG C.

The invention relates to an aluminum alloy section baggage holder for an automobile. The aluminum alloy section baggage holder for the automobile comprises a base material and a base material coveringlayer. The base material comprises the following elements in percentage by mass: 1% to 2% of chromium; 1% to 3% of copper; 2% to 3% of manganese; 0.05% 0.15% of zirconium; 0.03% to 0.09% of neodymium; 0.04% to 0.08% of vanadium; 0.5% to 1.0% of germanium; 0.5% to 0.9% of silicon boride fibers; 0.4% to 0.9% of silicon nitride fibers; 0.3% to 0.7% of silicon carbide fibers; 0.1% to 0.3% of nickel;0.05% to 0.08% of titanium; 1.2% to 2.5% of iron; 0.03% to 0.05% of palladium; 0.01% to 0.03% of lanthanum; 0.1% to 0.5% of cobalt; 1.5% to 3.5% of carbon fibers; 0.02% to 0.05% of graphite whiskers;and the balance of aluminum. The ultrahigh strength of the luggage holder is ensured; and the mechanical property of the luggage holder is improved.

The invention provides an electrical steel plate material and a preparation method thereof. The electrical steel plate material comprises a platelike electrical steel substrate, nick grooves in the surface of the substrate, and calcium silicate hydrate phase and magnesium silicate hydrate phase distributed on the surface of the nick grooves; the substrate is 0.1-2 mm in thickness; and the diameter of the calcium silicate hydrate phase and magnesium silicate hydrate phase is 1-100 nm. The preparation method comprises the following steps: 1), laser nicking processing; 2), (CaO+MgO) powder processing nick grooves: reacting the CaO, MgO with SiO2 on the surface of the nick grooves to generate the calcium silicate hydrate phase and magnesium silicate hydrate phase; and 3), washing the electrical steel plate material obtained in the step 2) and drying. The electrical steel plate material has excellent heat-resisting effect, namely, the iron loss reduction effect generated by the laser nicking is not eliminated, the original magnetic property of the electrical steel plate material can be maintained, and the insulating coatings on the silicon steel surface are not damaged when the electrical steel plate material is subjected to thermal insulation at the temperature of 800 DEG for 2 hours and annealing treatment; in addition, the preparation method is simple in operation, low in cost and suitable for large-scale industrial production.

The invention provides an electrical steel plate and a preparation method thereof. The electrical steel plate comprises a plate-shaped electrical steel substrate, etching grooves on the surface of the substrate and CaSiO3 phases distributed on the surface of the etching grooves, wherein the thickness of the substrate is 0.1 to 2 millimeters, and the diameter of the CaSiO3 phases is 1 to 100 nanometers. The preparation method comprises the following steps of: 1) carrying out laser etching treatment; 2) processing the etching grooves with CaO powder, wherein CaO and SiO2 on the surfaces of the etching grooves react to generate the CaSiO3 phases on the surfaces of the etching grooves; and 3) washing and drying the electrical steel plate. The CaSiO3 phases have strong pinning effects relative to tensile stress or dislocation of regions around the grooves, a processed laser etching product has excellent thermal resistance, the iron loss reduction effect generated by laser etching cannot be disappeared after the product is subjected to thermal insulation and annealing treatment at 800 DEG C for 2 hours, and the original magnetic performance is basically maintained. The method is simple in operation, and production and application at a large scale are promoted.

The invention discloses a carbon fiber reinforced resin matrix composite interface microcell structure regulation and control method which comprises the following steps: pretreating carbon fibers, removing surface slurry and impurities, then cleaning and drying to obtain carbon fibers with clean surfaces, loading a pure metal target material into a multi-arc ion plating arc head as a cathode, and carrying out high-temperature ion plating on the pure metal target material to obtain the carbon fiber reinforced resin matrix composite interface microcell structure. The pretreated carbon fibers are arranged on a rotating stand in a vacuum chamber, the vacuum chamber is vacuumized and heated, then argon is introduced, rich metal deposition is carried out on the surfaces of the carbon fibers, after deposition is completed, a sample is taken out, the sample is wrapped with graphite paper and then put into a graphite mold, then the graphite mold is put into an atmosphere protection furnace or a vacuum sintering furnace, and the carbon fibers are obtained. The preparation method comprises the following steps: heating a furnace to 900-1100 DEG C, carrying out an in-situ reaction, carrying out furnace cooling to obtain modified carbon fibers, and treating the modified carbon fibers and a resin solution through a vacuum-assisted resin injection molding process, a compression molding process or a resin transfer molding process to prepare the carbon fiber reinforced resin-based composite material.