147results about How to "Avoid grain growth" patented technology

A carbon-containing lithium-iron composite phosphorus oxide for a lithium secondary battery positive electrode active material, includes particles being composed of a lithium-iron composite phosphorus oxide having an olivine structure whose basic composition is LiFePO₄, and being composited with carbonaceous fine particles. A process for producing the same includes the steps of mixing a lithium compound making a lithium source, an iron compound making an iron source, a phosphorus-containing ammonium salt making a phosphorus source and carbonaceous fine particles, thereby preparing a mixture, and calcicing the mixture at a temperature of from 600° C. or more to 750° C. or less.

A method of forming a component from a gamma prime precipitation-strengthened nickel-base superalloy. The method entails formulating the superalloy to have a sufficiently high carbon content and forging the superalloy at sufficiently high local strain rates so that, following a supersolvus heat treatment, the component is characterized by a fine and substantially uniform grain size distribution, preferably finer than ASTM 7 and more preferably in a range of about ASTM 8 to 10.

A long life, low cost, high-temperature, high efficiency thermoelectric module. Preferred embodiments include a two-part (a high temperature part and a cold temperature part) egg-crate and segmented N legs and P legs, with the thermoelectric materials in the three segments chosen for their chemical compatibility or their figure of merit in the various temperature ranges between the hot side and the cold side of the module. The legs include metal meshes partially embedded in thermoelectric segments to help maintain electrical contacts notwithstanding substantial temperature variations. In preferred embodiments a two-part molded egg-crate holds in place and provides insulation and electrical connections for the thermoelectric N legs and P legs. The high temperature part of the egg-crate is comprised of a ceramic material capable of operation at temperatures in excess of 500° C. and the cold temperature part is comprised of a thermoplastic material having very low thermal conductivity.

The invention discloses a preparation method of nanometer molecular sieve. The method is to firstly mix hydrocarbon components and surfactants evenly, then add silica gel and silica-alumina gel, and continue to stir until the raw materials are evenly mixed to obtain a super-solubilizing system of oil-in-melt, and then undergo crystallization, drying and roasting Finally, nano molecular sieves are obtained. The crystallization of the molecular sieve in the present invention is carried out in a supersolubilized micelle system of molten silica gel or silica-alumina gel in oil, and the growth of the molecular sieve crystal is limited in the nano-micelle to avoid excessive growth of the molecular sieve crystal. The surfactant and hydrocarbon components used in the method of the invention are used in small amounts and low in cost. The method has a simple process and can be used for large-scale industrial production.

Disclosed are a porous material comprising particles without substantial fibrous structure and having pores, the pores having a mean pore diameter in a meson-pore region, sharp pore size distribution, and at least a part of the pores being connected three-dimensionally to form a three-dimensional network structure with random passages, the porous material preferably being of alumina and having a spongy structure or the porous material preferably being an aggregate of particles having an aspect ratio of 3 or less; a process of producing the porous material which includes a step of aging a system capable of becoming an oxide on thermal decomposition; a catalyst for exhaust gas purification having excellent NO_x removal performance, high resistance against sulfur poisoning, and satisfactory high-temperature durability which comprises the porous material as a carrier having supported thereon a noble metal and an NO_x storage component; and a method of exhaust gas purification using the catalyst.

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.

A method of manufacturing a workpiece is provided. The method generally includes friction stir welding at least one structural member, selectively removing material from the surfaces of the workpiece at the location of a friction stir weld joint, and thereafter subjecting the workpiece to a solution treat, quench, and age treatment. By selectively removing regions from the surfaces of the workpiece that are defined by nonuniform material properties adapted to nucleate nonuniform grain growth during the solution treat, quench, and age treatment, a subsequent grain growth during the thermal treatment can be at least partially prevented.

A bonded SOI wafer is manufactured by bonding a bond and a base wafer, each composed of a silicon single crystal, via an insulator film, depositing a polycrystalline silicon layer on the bonding surface side of the base wafer, polishing a surface of the polycrystalline silicon layer, forming the insulator film on the bonding surface of the bond wafer, bonding the polished surface of the polycrystalline silicon layer and the bond wafer via the insulator film, and thinning the bonded bond wafer to form an SOI layer; wherein, the base wafer is a silicon single crystal wafer having a resistivity of 100 Ω·cm or more, depositing the polycrystalline silicon layer further includes a stage for previously forming an oxide film on the surface of the base wafer on which the polycrystalline silicon layer is deposited, and the polycrystalline silicon layer is deposited at a temperature of 900° C. or more.

The invention relates to a method for preparing nano titanium diboride polycrystalline powder, which comprises the following steps of: mixing raw materials B2O3, TiO2, Mg and KBH4 uniformly, directly performing self-propagating reaction or performing self-propagating reaction after briquetting on the obtained mixed raw materials, and separating and purifying the self-propagating reaction product to obtain the nano titanium diboride polycrystalline powder. The method has the advantages that: (1) the method controls the heat effect of the reaction system, can save energy, reduce the self-propagating reaction temperature and inhibit side reaction and byproduct impurities, and greatly improves the purity of the product; (2) a large amount of gas formed in the reaction process inhibits product grain growth and sintering agglomeration and realizes grain size control of the nano TiB2; and (3) the method has simple reaction process and technique, is easy to control and suitable for industrial production, reduces the preparation cost for preparing the nano titanium diboride polycrystalline powder, and has great utility value.

A catalyst for purification of exhaust gas in which a noble metal is supported on a metal-oxide support wherein, in a oxidation atmosphere, the noble metal exists on the surface of the support in high oxidation state, and the noble metal binds with a cation of the support via an oxygen atom on the surface of the support to form a surface oxide layer and, in a reduction atmosphere, the noble metal exists on the surface of the support in a metal state, and an amount of noble metal exposed at the surface of the support, measured by CO chemisorption, is 10% or more in atomic ratio to a whole amount of the noble metal supported on the support.

The present invention provides a cemented carbide with superior strength and toughness by refining the WC in the alloy uniformly and by restricting the growth of coarse WC efficiently. In this cemented carbide, WC with a mean particle diameter of no more than 0.3 microns serves as a hard phase and at least one type of iron group metal element at 5.5-15 percent by mass serves as a binder phase. In addition to this hard phase and binder phase, this cemented carbide contains 0.005-0.06 percent by mass of Ti, Cr at a weight ratio relative to the binder phase of at least 0.04 and no more than 0.2, with the remaining portion being formed from inevitable impurities. In particular, this cemented carbide does not contain Ta.

The invention provides cold work die steel. The cold work die steel comprises C, Si, Mn, Cr, Mo, W, V, P, S, Cu, Mg, Ti, Sr, Zr, B, Zn, Re, Sn, Pb, Be, Sc, Li, Ni, La, Al and the balance iron, wherein the sum of the mass percentages of the components is 100%. The nodular cast iron comprises multiple kinds of nonmetal, metal and transition metal elements. Because the elements are added and cooperate with one another, the oxidation resistance, the corrosion resistance, the abrasion resistance, the compression resistance and the shock resistance of a compressor cylinder block of an air conditioner are improved, and the service life of the compressor cylinder block of the air conditioner under severe working conditions is prolonged.

The invention discloses nanostructured lithium orthosilicate ceramic spheres used for tritium propagation and a preparation method thereof. The nanostructured lithium orthosilicate ceramic spheres are made by preparing precursor powder with uniform particle size through a solvothermal method, obtaining a lithium ceramic sphere blank with a uniform microstructure through wet moulding, and carrying out two-step sintering. The prepared lithium orthosilicate ceramics is high in purity, good in sphericility, small in hole size and uniform in hole dispersion, has a crystal grain size in nanometer order and allows the radiation resistance, mechanical properties and tritium release properties of tritium propagation ceramics to be improved at the same time.

With a multilayer ceramic capacitor whose average grain size of the dielectric grains present at the outermost layer position P₁ in the laminate is given by D₁, average grain size of the dielectric grains present at the center position P₂ in the laminate is given by D₂, and average grain size of the dielectric grains present at the 25%-penetrated position P₃ which is a position penetrated into the laminate by 25% is given by D₃, growth of the dielectric grains occurring as a result of sintering is partially suppressed in such a way that the relationships of average grain sizes D₁, D₂, and D₃ satisfy the conditions of 1.5×D₁<D₃ and 1.2×D₂<D₃. This way, a sufficient CR product can be obtained even with a dielectric thickness of 1 μm or less.

The invention discloses a method and a product for preparing an ultra-thin porous WO3 gas-sensitive coating by using a thermal spraying technology. The preparation method comprises the following steps: (1) preparing a WC16 liquid-phase precursor; (2) cleaning a substrate, degreasing, derusting and carrying out surface roughening treatment; (3) feeding the WC16 liquid-phase precursor prepared in the step (1) to thermal spraying equipment, and carrying out high-temperature reaction, drying, burning, coagulation and sedimentation on the surface of the substrate so as to obtain the ultra-thin porous WO3 gas-sensitive coating. The preparation method disclosed by the invention has the advantages of simple operation, fewer technological processes, low cost, applicability to industrial production and the like, and the prepared WO3 gas-sensitive coating has an ultra-thin porous submicrometer structure, and has excellent gas sensitivity, and the thickness is 500nm to 1mu m.

There are provided a permanent magnet and a manufacturing method thereof capable of inhibiting grain growth of magnet grains having single domain particle size during sintering so as to improve magnetic properties. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)_x (M represents V, Mo, Zr, Ta, Ti, W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, _x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, the desiccated magnet powder is calcined by utilizing plasma heating and the powdery calcined body is sintered so as to form a permanent magnet 1.

The invention discloses an extruding, forging and rolling integrated technology of an AQ80M magnesium alloy annular part. The technology comprises the steps of semi-continuous casting, homogenizing annealing, heat extrusion, multi-direction forging, mechanical hole punching and annular part rolling. The extruding, forging and rolling integrated technology can be used for producing and preparing the AQ80M magnesium alloy annular part which is free of cracks on the surface, uniform in structure, good in comprehensive mechanics property, small in mechanical anisotropy and large in size, the annular part can be used for replacing annular parts made of other materials, the effects of reducing weight, improving the fuel efficiency and achieving electromagnetic shielding are achieved, and the technology has the important application value in aerospace and national defense fields.

The invention belongs to the technical field related to additive manufacturing, and more particularly, relates to a shape and property integrated metal component additive manufacturing system. The shape and property integrated metal component additive manufacturing system comprises an object carrying platform, a multi-electric arc collaborative operation module, an electric arc camera shooting detection unit, a forming size three-dimensional measurement unit, a depositing forming digital monitoring module and the like, and uniform control is executed through a negative feedback monitoring module. The multi-electric arc collaborative operation module is equipped with a plurality of mutually independent electric arc guns, and relative positions and operating postures of the electric arc guns freely change. Through the shape and property integrated metal component additive manufacturing system, electric arc additive manufacturing overall processes of various large metal components can be executed based on a compact structure, convenience in control, high automaticity and high manufacturing accuracy, and the requirements of shape and property integrated collaborative additive manufacturing are met better.

The electronic device according to the present invention comprises capacitor element body 4 wherein internal electrode layer 12 and ceramic layer 10 is included. Internal electrode layer 12 includes Ni and at least one element from Re, Ru, and Ir. The ceramic layer 10 substantially doesn't include Re, Ru, Os, and Ir.

There are provided a permanent magnet and a manufacturing method thereof capable of decreasing an activity level of a calcined body activated by a calcination process. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)_x (M represents V, Mo, Zr, Ta, Ti, W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, _x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, desiccated magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius. Thereafter, the powdery calcined body calcined through the calcination process in hydrogen is held for several hours in vacuum atmosphere at 200 through 600 degrees Celsius for a dehydrogenation process.