172results about How to "Control grain size" patented technology

The invention discloses a preparation method of nano-silver loaded porous silicon dioxide. The preparation method of nano-silver supported porous silicon dioxide comprises the step of preparing hierarchy porous silicon dioxide by polyoxyethylene, and also comprises the following steps: 1) modifying the hierarchy porous silicon dioxide by taking amino propyl triethoxy silicane as a modifying agent and by adopting absolute ethyl alcohol as a modifying solvent; 2) loading: dissolving silver nitrate into glycol as a reducing agent, and carrying out magnetic stirring so as to obtain a glycol solution of silver nitrate; firstly, cleaning the modified hierarchy porous silicon dioxide obtained in the step 2) with deionized water, and then putting into the glycol solution of silver nitrate, and loading for 48-72 hours in a baking oven at 35-45 DEG C; forming nanoscale silver particles by taking glycol as a reducing agent to reduce silver nitrate; loading the nano silver particles to the modified hierarchy porous silicon dioxide; 3) drying the obtained material in the step 2) after cleaning, thereby obtaining the nano silver loaded porous silicon dioxide.

The invention provides a powder metallurgical method for IN718 alloy. The powder metallurgical method for the IN718 alloy comprises the following steps: firstly, preparing spherical powder of the IN718 alloy by adopting a plasma rotating electrode process; secondly, putting the spherical powder into a stainless sheath, carrying out vacuum degassing for 4-8 hours at the temperature of 400-800 DEG C, and soldering and sealing the opening of the sheath; and thirdly, carrying out hot isostatic pressure treatment on the sheath after being soldered and sealed, namely firstly carrying out heat and pressure preservation for 2-4 hours at the temperature of 1210-1270 DEG C and the pressure more than 120 MPa, lowering the temperature to be 1100-1160 DEG C while the pressure condition is not changed, continuously carrying out heat and pressure preservation for 2-4 hours, and finally cooling to room temperature at a cooling rate more than 50 DEG per minute. The powder metallurgical method for the IN718 alloy is simple in technology, only hot isostatic pressure temperature is changed, an extra working process does not need to be added, adverse effect of carbon and oxides on particle surfaces can be effectively eliminated without increasing cost, and mechanical properties of the alloy are obviously improved.

The invention discloses an aluminium alloy with high forming property for an automobile body plate, comprising the following chemical constituents in percentage by weight: 0.50-1.20wt% of Si, 0.35-0.70wt% of Mg, 0.01-0.20wt% of Cu, 0.05-0.20wt% of Mn, less than or equal to 0.10wt% of Cr, 0.01-0.25wt% of Zn, less than or equal to 0.15wt% of Ti, 0.05-0.15wt% of Fe and the balance of Al. The aluminium alloy material of the invention has lower yield strength before baking finish, which is favourable for stamping shaping; and after baking finish, the yield strength is improved. The material has higher forming property and simultaneously satisfies the requirements of the impact resistance of the automobile body plate.

The invention discloses a method for preparing a macroporous hollow-sphere titanium oxide photocatalytic material for photocatalytic degradation of pollutants. The method aims to provide a macroporous hollow-sphere titanium oxide preparation technique to obtain a material with optimal degradation capacity. The method comprises the following steps: by using a glucose solution as a raw material, preparing colloid carbon spheres under hydrothermal conditions; and by using tetra-n-butyl titanate as a precursor, preparing a uniform-particle high-activity high stability macroporous hollow-sphere titanium oxide photocatalyst by sol-gel and calcination processes. The keys of the preparation process are synthesis of the colloid carbon spheres and the sol-gel technique. The method has the advantages of simple technique, mild conditions and favorable repetitiveness, can be widely used for photocatalytic degradation of organic pollutants, and has wide application prospects in the aspect of environmental treatment.

The invention discloses a method for preparing nanoscale boron modified HZSM-5 by seed crystal directing. The method comprises the steps as follows: (1) mixing an aluminum source, a silicon source, an alkali source, a boron source, ZSM-5 molecular sieve seed crystals and water, adjusting the pH of an obtained mixture to 10-12 and mixing the mixture uniformly to form gel; (2) crystallizing the gel in a reactor, and performing solid-liquid separation, washing and drying on a crystallized product to obtain a dried crystallized product; (3) adding the dried crystallized product in an ammonium salt solution for ion exchange to obtain an ammonia type ZSM-5 molecular sieve; (4) roasting the ammonia type ZSM-5 molecular sieve to obtain HZSM-5. The invention further discloses a molecular sieve prepared by the method and application of the molecular sieve in a reaction of methanol to propylene. The boron modified HZSM-5 requires no roasting of a template agent and is environment-friendly, the propylene yield and the service life are greatly increased, the selectivity of propylene reaches 44.0wt% or higher, and the service life reaches 500 h or longer.

The invention discloses a non-annealed cold forging steel hot-rolled wire rod and a production method thereof. The method comprises the steps of continuous casting, heating, rolling, spinning and cooling. The non-annealed cold forging steel hot-rolled wire rod comprises 0.29-0.38wt% of C, 0.15-0.30wt% of Si, 0.70-0.90wt% of Mn, 0.03wt% or less of P, 0.03wt% or less of S, 0.30wt% or less of Cr, 0.0008-0.0050wt% of B, and the balance of Fe and residual elements. In the heating step, continuous cast billets are heated to 1100-1190DEG C; in the rolling step, the initial finish rolling temperature is 965-995DEG C; in the spinning step, the spinning temperature is 960-990DEG C; and in the cooling step, the cooling speed is 0.5-1.5DEG C/s. The method realizes production of the non-annealed cold forging steel hot-rolled wire rod through optimally designing chemical components, controlling the heating temperature, the initial finish rolling temperature, the spinning temperature and the cooling speed and controlling the amount and the grain size of ferrite by using present devices and technologies without increasing investment or production cost, so the non-annealing production and cost reduction demands of downstream users are met, and pollution of annealing to environment is avoided.

The invention discloses coal ash microsphere loaded one-dimensional nanometer titanium dioxide (TiO2) composite photocatalyst and a preparation method thereof. The coal ash microsphere loaded one-dimensional nanometer TiO2 composite photocatalyst consists of a coal ash microsphere and a one-dimensional nanometer TiO2 film covered on the surface of the coal ash microsphere, wherein the coal ash microsphere is in a thin-wall hollow structure; the external diameter of the coal ash microsphere is 100-200 micrometers; the thickness of the wall is 2-6 micrometers; the thickness of the one-dimensional nanometer TiO2 film is about 0.5-3 micrometers; and the TiO2 is in the one-dimensional nanometer structure. The composite photocatalyst disclosed by the invention is easy to disperse, recover and use in liquid medium, has a higher reaction activity and has a wide application prospect on the water body purification aspect, and a purpose of effectively removing organic pollutants in the water body can be achieved.

The invention provides a method for preparing cobaltosic oxide with large grain size and high safety, comprising the following steps: preparing the raw material cobalt and a precipitant into cobalt solution and precipitant solution with deionized water, adding the cobalt solution and the precipitant solution which are prepared to certain concentration to a reaction vessel by the charging methods including cocurrent charging according to certain molar ratio, preparing the cobalt salt precursor by controlling the reaction temperature, charging speed, PH value and stirring speed, washing and dehydrating the precursor, directly putting the water-containing filter cake into a pot, spheroidizing and calcining the pot at high temperature, carrying out mechanical grinding, grading and activating, controlling the grain size and the crystal morphology and finally removing the magnetic metal foreign bodies, thus finally obtaining the high quality battery grade cobaltosic oxide. The method is simple in process, easy to operate, low in cost, energy-saving, environment-friendly and suitable for industrial production. The prepared cobaltosic oxide looks like spheroid and has large grain size, good powder flowability and uniform granularity.

The invention relates to a method for making a 17-7PH thick wall seamless pipe, which comprises the steps of: 1, cold deformation, wherein cold-rolling and cold-drawing integrated production process is adopted, the external diameter dereduction factor is controlled to be 25-32 percent, the wall thickness reduction rate is controlled to be 16-20 percent, the distortion is controlled to be 38-50 percent; 2, baking at low temperature after drawing the external diameter, wherein the baking temperature is 200-300 DEG C and the baking time is 20-30min; 3, heat treatment, wherein a continuous roller hearth furnace is adopted in a middle heat treatment process, the solid solution temperature is 1050-1080 DEG C, and the heat preservation time is controlled to be 35-60min; and the heat treatment for a finished product adopts a continuous type roller hearth furnace, the heat treatment process is a solid solution and aging integrated treatment process, the solid solution temperature is 1040-1060 DEG C, and the heat preservation time is 20-30min; 4, scouring, wherein the scouring temperature is controlled to be 40-60 DEG C and the scouring time is controlled to be 15-20min; and 5, straightening, deoiling, degreasing, cutting and hammering. The invention reduces cold machining pass, prevents the pipe from longitudinally cracking, meets the requirement on magnetic conductivity of the finished product, provides surface quality, and controls the size of the finished product.

The invention discloses a thin film transistor low-temperature polycrystalline silicon thin film manufacturing method. The method includes the steps of firstly, sequentially depositing an isolation layer, a non-crystalline silicon layer and an anti-reflection heat preservation layer on a glass substrate where a TFT metal grid is plated in advance; secondly, coating the anti-reflection heat preservation layer with photoresist through a picture composition process, and conducting mask exposure and developing through the TFT metal grid; thirdly, etching the portion, in a non-channel area, of the anti-reflection heat preservation layer, and conducting demolding on the photoresist; fourthly, conducting laser radiation so that the non-crystalline silicon of a channel area can be converted into large-size polycrystalline silicon. By means of the technical scheme, the temperature gradient of the TFT channel area and the non-channel area can be formed, the manual-control super transverse growth of crystalline grain from the non-channel area to the channel area can be achieved, the TFT channel area has only one grain boundary, and therefore the carrier migration rate is increased, and the performance of a device in a channel is uniform.

The invention provides an annealing process of an aluminum alloy coiled material. According to the annealing process provided by the invention, the annealing time is greatly shortened,the problem of poor finished material coil head-tail structure property difference generated when annealing treatment is carried out on an aluminum-magnesium alloy coiled material is solved by adopting an existing aluminum alloy annealing process, the size of a crystal grain can be effectively controlled and the plasticity and toughness of a finished product state coiled material are improved. The annealing process is characterized by comprising the following steps: placing the aluminum alloy coiled material into an annealing heating furnace; fast heating the aluminum alloy coiled material by setting the furnace gas temperature of the annealing heating furnace as T+delta T, and monitoring the temperature of the aluminum alloy coiled material; when the outer side temperature of the aluminum alloy coiled material, namely the high-point temperature of the aluminum alloy coiled material, reaches T-delta t, reducing the furnace gas temperature of the annealing heating furnace to T, wherein the temperature reduction time is 60-90 minutes; and when the inner side temperature of the aluminum alloy coiled material, namely the low-point temperature of the aluminum alloy coiled material, is monitored to reach T-(5-30 DEG C), preserving heat for 60-120 minutes, and then taking out of the furnace for air-cooling, wherein the temperature T is the predetermined target temperature of the annealing of the aluminum alloy material, the delta T is 20-150 DEG C, and the delta t is 10-70 DEG C.

The invention discloses a method for preparing rare earth titanate nanocrystalline with the controllable size through self-propagating combustion. The method comprises the following steps of: hydrolyzing titanic alkoxide to obtain oxygen titanium hydroxide, and dissolving the oxygen titanium hydroxide in a salpeter solution to obtain nitric acid oxygen titanium; placing rare earth nitrate, the nitric acid oxygen titanium and glycine in an evaporating dish, and placing the evaporating dish on a magnetic stirring apparatus so as to volatilize liquid; continuously heating under the stirring condition, stopping stirring when sparkle occurs, wherein the sparkle rapidly spread and burns, and obtaining fluffy rare earth titanate powder on the evaporating dish in the end. According to the method, the glycine is taken as a fuel and is subjected to self-propagating combustion by using heat generated by the oxidation-reduction reaction happening between the rare earth metal titanate and the glycine, so that the rare earth titanate nanocrystalline is rapidly synthesized. The regulation and control of crystalline size of the rare earth titanate can be realized by adjusting and controlling the molar ratio of nitrate ions to the glycine. The method disclosed by the invention has the advantages of being short in reaction time, simple in technology and environment-friendly; equipment is simple; and the production cycle is short.

The invention belongs to the technical field of energy materials, in particular relates to a method for preparing polycrystalline textured thermoelectric materials from single-crystal bismuth sulfide precursor powder. Specifically, the method comprises the following steps of: selecting uniformly-orientated single-crystal bismuth sulfide [Bi2S(3-x), 0<=x<=0.5] powder (including nanoflakes, nanotubes and nanowires) as precursor powder; performing rapid sintering under increased pressure by using a spark plasma sintering technique so that the single-crystal powder trends to be arranged in the direction perpendicular to the pressure and freeze to form highly-textured dense polycrystalline bulk thermoelectric materials; and controlling the texture degree, the crystal grain degree and the density of the bulk materials by adjusting the applied pressure, the sintering temperature and the heat retention time. Owing to the texture, the polycrystalline materials show strong anisotropy, so that the power transmission performance is greatly improved.