42results about How to "Achieve sintering" patented technology

The invention relates to oxide-dispersion-strengthening ferrite / martensitic steel with the excellent high-temperature strength and the good oxidation resistance and a preparing method of the oxide-dispersion-strengthening ferrite / martensitic steel. The oxide-dispersion-strengthening ferrite / martensitic steel comprises 8% to 10% of Cr, 0.5% to 2% of W, 1.5% to 5.5% of Al, 0.1% to 0.4% of V, 0.1% to 0.5% of Mn, 0% to 1.0% of Zr, 0% to 1.0% of Hf and 0.25% to 0.5% of Y2O3. The content of C and the content of N are controlled to be lower than 0.1%, and at least one kind of the Hf and the Zr is contained; the oxygen content of atomized powder is controlled to be lower than 0.05 wt.%, the atomized powder with the particle size ranging from 50 meshes to 200 meshes is selected to be mechanically alloyed with Al powder, Zr powder, Hf powder and Y2O3 powder, and the size of obtained powder ranges from 90 micrometers to 200 micrometers; silicate glass is used for wrapping, compressing and molding, the pressure is started to be boosted to 120 MPa to 180 MPa at the temperature of 850 DEG C, a two-stage sintering manner in which the temperature ranging from 850 DEG C to 950 DEG C is kept for 1 hour and the temperature ranging from 1050 DEG C to 1150 DEG C is kept for 1 hour is adopted, the tensile strength of the finally-obtained ferrite / martensitic steel at the temperature of 700 DEG C ranges from 250 MPa to 320 MPa, and the ductility of the finally-obtained ferrite / martensitic steel at the temperature of 700 DEG C ranges from 18% to 32%; and the oxidation performance of the dispersion-strengthening steel is also greatly improved on the premise that the high-temperature strength and the high-temperature plasticity are guaranteed, and after 100-h oxidation is carried out at the temperature of 850 DEG C, the oxidation weight increase only ranges from 0.0327 mg / cm<3> to 0.098 mg / cm<3>.

The invention relates to a low-temperature normal-pressure sintering preparation method of a mass-producible high-purity SiC ceramic coating, which is applied to the fields needing high-temperature resistance, oxidation resistance, corrosion resistance and other protective properties in the form of coatings. The preparation method is technically characterized by comprising the following steps: preparing high-purity SiC slurry, carrying out brush-coating, and carrying out low-temperature pressureless sintering. According to the technical scheme provided by the invention, the purity and the sintering temperature of the SiC coating are controlled by regulating and controlling the formula of the high-purity SiC slurry, so that normal-pressure sintering and industrial preparation and productionof the high-purity SiC coating at the temperature of 1750-1800 DEG C are realized. The high-purity SiC slurry formula and the brush-coating and sintering processes are flexible and controllable, thecoating and the matrix are well combined, obvious peeling and cracks are avoided, the technological process is easy to operate and short in consumed time, and the cost is greatly reduced.

The invention discloses a method for preparing porous ceramic by coating beta-Si3N4 particles with a composite oxide CaO-SiO2-B2O3, which is a porous body preparation technology comprising the following steps: the beta-Si3N4 particles are put into a CaO-SiO2-B2O3 sol made from tetraethoxysilane, boric acid, calcium nitrate, citric acid, absolute ethyl alcohol and deionized water, and the vacuum filtration method is adopted to form the porous body by self porous structure of the columnar beta-Si3N4 crystalline particles. The surface of the sintered beta-Si3N4 particles is coated with a modification layer of CaO-SiO2-B2O3 oxide interface, and the modification layer effectively connects the beta-Si3N4 particles and prevents the beta-Si3N4 particles from oxidation at high temperature. The porous ceramic prepared by the method can be used as a radome and a catalyst carrier material.

The invention discloses a novel rotary kiln which comprises a kiln body and a kiln car. The kiln body is of an annular structure integrally, the kiln car is provided with a drying section, a preheating section, a high-temperature calcining section and a cooling section, the kiln body integrally falls into the ground to form a trench-type structure, an air suction passage is formed on two side faces or at the bottom of the cooling section of the kiln body, a passage is formed below the bottom of the kiln body to form a main flue, an air feeding flue is formed on two side faces or at the bottom of each of the cooling section and the drying section, and the main flue is communicated with the air suction flue and the air feeding flues. Waste heat of finished brick products and hot air are extracted from the side faces of the cooling section of the trench-type rotary kiln to enter the main flue at the bottom, and are divided to enter the air feeding passages after reaching the drying section, and the air feeding flues feed hot air from the side face of the kiln body into the drying section in the kiln body to dry wet blank bricks.

The invention relates to oxide-dispersion-strengthening ferrite / martensitic steel with the excellent high-temperature strength and the good oxidation resistance and a preparing method of the oxide-dispersion-strengthening ferrite / martensitic steel. The oxide-dispersion-strengthening ferrite / martensitic steel comprises 8% to 10% of Cr, 0.5% to 2% of W, 1.5% to 5.5% of Al, 0.1% to 0.4% of V, 0.1% to 0.5% of Mn, 0% to 1.0% of Zr, 0% to 1.0% of Hf and 0.25% to 0.5% of Y2O3. The content of C and the content of N are controlled to be lower than 0.1%, and at least one kind of the Hf and the Zr is contained; the oxygen content of atomized powder is controlled to be lower than 0.05 wt.%, the atomized powder with the particle size ranging from 50 meshes to 200 meshes is selected to be mechanically alloyed with Al powder, Zr powder, Hf powder and Y2O3 powder, and the size of obtained powder ranges from 90 micrometers to 200 micrometers; silicate glass is used for wrapping, compressing and molding, the pressure is started to be boosted to 120 MPa to 180 MPa at the temperature of 850 DEG C, a two-stage sintering manner in which the temperature ranging from 850 DEG C to 950 DEG C is kept for 1 hour and the temperature ranging from 1050 DEG C to 1150 DEG C is kept for 1 hour is adopted, the tensile strength of the finally-obtained ferrite / martensitic steel at the temperature of 700 DEG C ranges from 250 MPa to 320 MPa, and the ductility of the finally-obtained ferrite / martensitic steel at the temperature of 700 DEG C ranges from 18% to 32%; and the oxidation performance of the dispersion-strengthening steel is also greatly improved on the premise that the high-temperature strength and the high-temperature plasticity are guaranteed, and after 100-h oxidation is carried out at the temperature of 850 DEG C, the oxidation weight increase only ranges from 0.0327 mg / cm<3> to 0.098 mg / cm<3>.

The invention discloses a preparation method of a high-strength silicon carbide porous ceramic. Raw materials are composed of 98%-99% of mixture of alpha-silicon carbide powder and beta-silicon carbide powder, 0.1%-1.0% of aluminum diboride and 0.5%-1% of polycarbosilane, by weight percent. The method comprises the following steps: 1) adding the raw materials into an organic dispersing solvent, ball-milling, mixing and drying; 2) dry-pressing and forming the obtained silicon carbide compound powder under the 45-55 MPa; and 3) placing a silicon carbide blank into a vacuum pressure-less sintering furnace, for sintering at two steps, thereby obtaining the high-strength silicon carbide porous ceramic. The preparation method is simple and the prepared silicon carbide porous ceramic is characterized by high mechanical strength, suitable porosity, and the like.

The invention discloses an aluminum-silicon alloy binding agent diamond abrasive disc and a manufacture method thereof. An aluminum-silicon alloy binding agent comprises, by weight, 0%-30% of Si, 0.25%-6% of Ti, 0%-0.5% of Mg, 0%-5% of Cu, 0%-0.5% of Ga, 0%-0.5% of Ce, 0%-0.5% of Sr, 0%-0.5% of of Na and the balance Al and inevitable impurities. The aluminum-silicon alloy binding agent and diamondpowder are sufficiently mixed; after the mixture is subjected to cold press molding, vacuum hot pressing sintering is conducted under a certain sintering process, and aluminum-silicon alloy based diamond abrasive disc section blocks are obtained; and then the diamond abrasive disc section blocks obtained through sintering are installed on and connected to an abrasive disc base body, and the diamond abrasive disc is obtained. By means of the aluminum-silicon binding agent adopted for the aluminum-silicon alloy binding agent diamond abrasive disc, low-temperature sintering can be achieved, anddiamond thermal damage is reduced; and meanwhile by introducing the active Ti element, the holding capacity of diamond abrasive particles can be remarkably increased, the wear resistance of the abrasive disc is improved through the aluminum-silicon binding agent and the Ti element together, and the service life of the diamond abrasive disc is prolonged.

The invention provides a low-cost batch preparation method and application of a noble metal electrode array. The method comprises the following steps: mixing an aqueous solution of noble metal nanoparticles with an inorganic salt aqueous solution with a certain concentration in an isopyknic manner, and aggregating the noble metal nanoparticles to increase the particle size by utilizing a salting-out effect; pouring the mixed solution into a device fixed with a templated microporous filter membrane, and carrying out rapid deposition and room-temperature sintering on the aggregated noble metal nanoparticles in a blank area of the microporous filter membrane in a reduced-pressure filtration manner to form a patterned electrode array; and finally, carrying out washing and drying treatment, soas to produce the low-cost and high-conductivity noble metal electrode array in batches. The method utilizes a template filtering method and has the characteristics of simple preparation device and process, low preparation cost, high material utilization rate and the like. The prepared electrode array is easy to modify, controllable in thickness and good in uniformity and conductivity, and has a wide application prospect in the fields of electrochemical sensors, flexible electronic devices and the like.

The invention relates to a soft magnetic composite powder and its application. The preparation method of the soft magnetic composite powder is as follows: according to the ferrite soft magnetic chemical formula; prepare the water-soluble metal salt corresponding to the metal element in the ferrite, and make solution A; make the precipitant into solution B; Add magnetic metal powder into water to obtain suspension C; add solution A and B to C and co-precipitate at the same time to obtain coated powder; then perform low-temperature calcination under oxygen-containing atmosphere and high-temperature calcination under inert atmosphere in sequence; obtain composite powder . The specific scheme of the application is: add coupling agent, silicone resin and lubricant to the composite powder; select powder with appropriate particle size after drying; High-temperature annealing under atmosphere to obtain soft magnetic composite materials. The composite powder prepared by the invention has higher magnetic properties and resistivity, and the soft magnetic composite material has better magnetic properties, frequency stability and wider use frequency.

The invention discloses a novel rotary kiln which comprises a kiln body and a kiln car. The kiln body is of an annular structure integrally, the kiln car is provided with a drying section, a preheating section, a high-temperature calcining section and a cooling section, the kiln body integrally falls into the ground to form a trench-type structure, an air suction passage is formed on two side faces or at the bottom of the cooling section of the kiln body, a passage is formed below the bottom of the kiln body to form a main flue, an air feeding flue is formed on two side faces or at the bottom of each of the cooling section and the drying section, and the main flue is communicated with the air suction flue and the air feeding flues. Waste heat of finished brick products and hot air are extracted from the side faces of the cooling section of the trench-type rotary kiln to enter the main flue at the bottom, and are divided to enter the air feeding passages after reaching the drying section, and the air feeding flues feed hot air from the side face of the kiln body into the drying section in the kiln body to dry wet blank bricks.

The invention relates to the field of vanadium-titanium-magnetite concentrate preparation, in particular to a sintering method for vanadium-titanium-magnetite concentrate which can effectively improve the quality of sintered ore products. Fluorite ore powder, 65-75 parts of vanadium-titanium magnetite concentrate, 3-8 parts of limestone powder, 6-10 parts of active lime and 4.5-5 parts of coke powder are mixed to form a mixture, and the mixing is controlled The alkalinity of the material is 1.8 to 2.4; water is added to the mixture, and the weight percentage of water in the mixture after adding water is controlled to be 7.2% to 7.6%; the first mixing granulation and the second mixing The material after the second mixing and granulation is added to the sintering machine for sintering, and finally the finished product is obtained. The invention controls the proportion of each material, realizes the sintering of vanadium-titanium magnetite concentrate, increases the binding phase of the sintered ore, increases the liquid phase generation amount in the sintering process, and improves the strength of the vanadium-titanium sintered ore. The invention is especially suitable for the sintering process of vanadium titanomagnetite concentrate.