340results about How to "Raise the sintering temperature" patented technology

The invention discloses a sintered water permeable brick and a preparation method thereof, and belongs to the technical field of sintered ceramics. According to the water permeable brick, structural pug in a surface layer is composed of, by weight, 45-65% of structural fine aggregates, 20-30% of plastic high-temperature binders and 15-25% of water, pore forming pug in the surface layer is composed of, by weight, 20-50% of pore forming agent aggregates, 45-80% of plastic pore adding binders and 0-5% of biomass fuel internal combustion catalysts, and a blank of a secondary surface layer is composed of, by weight, 70-75% of coarse structural aggregates, 10-15% of plastic high-temperature binders, 0-5% of pore adding agent coarse aggregates and 10-15% of water. A blank of the surface layer and the blank of the secondary surface layer are prepared firstly, the blank of the surface layer contains the orderly distributed structural pug and the pore forming pug, and then single-shaft extrusion forming, drying and sintering are conducted to obtain the water permeable brick. The water permeable brick has high water permeable rate, high strength, high abrasion resistance and durability and is a paving material with excellent ecological and environmental functions.

A sintering method for valve metal powders, such as tantalum, niobium, aluminum, titanium, and their alloys, is described. The valve metal powders are pressed into a pellet and sintered at a relatively high temperature, but for a relatively short time. The anodized valve metal structure is then useful as an anode in an electrolytic capacitor.

The invention discloses an iron mine sintering flue gas segmented circulation method. Sintering flue gas high in O2 content on the tail portion of a sintering machine is circulated to the interior of a head flue cover of a sintering feed surface of the head portion of the sintering machine, flue gas of two to three bellows highest in SO2 content in a bellow on the tail portion of the sintering machine is conveyed to a desulfurization system to be desulfurized, and flue gas in other bellows is circulated to a middle flue cover of a sintering feed surface of the middle portion of the sintering machine. After segmented flue gas circulation is adopted, SO2 will not be accumulated in sintering ore, dust emission is reduced by 20-40%, NOx emission is reduced by 20-40%, dioxin emission is reduced by 50-80%, and CO2 emission is reduced by 20-45%.

The invention discloses a sintering preparation method of boron carbide ceramic, which comprises the following steps: 1. sintering: carrying out mixing and ball milling on boron carbide powder, carbon powder, metal powder, a dispersant, an adhesive and deionized water to make a slurry, carrying out spray granulation, pressing into a biscuit, presintering for debonding, and carrying out thermal-insulation sintering at lower sintering temperature (slightly higher than the melting point of metal), thereby implementing primary shrinkage sintering of the product by utilizing the surface tension of the molten metal in the system; and 2. sintering: continuing enhancing the sintering temperature, carrying out in-situ reaction to generate metal carbide, metal boride or metal boro-carbide and nano B4C which have higher sintering activity, and forming a solid solution with boron carbide granules by using the metal carbide, metal boride or metal boro-carbide and nano B4C as sintering assistants to promote the further shrinkage sintering of the system, thereby obtaining the high-performance boron carbide ceramic. The method has the advantages of both the normal-pressure sintering technique and the reactive sintering technique.

A green article comprising an A-B powder mixture and methods of manufacturing such green articles and corresponding sintered articles are disclosed. The A-B powder mixture consists of a minor volume fraction of a relatively fine powder A and a complementary major volume fraction of a relatively coarse prealloyed powder B wherein the A-B powder mean particle size ratio is at least about 1:5. Metal powder A consists of one or more elemental metals or alloys which has a melting or solidus temperature above the highest sintering temperature at which the A-B powder mixture may be sintered without slumping. Prealloyed metal powder B consists of one or more alloys which are amenable to supersolidus liquid phase sintering. Green articles made from the A-B powder have a wider sintering temperature window than do articles made from prealloyed metal powder B alone.

The invention discloses a method for manufacturing a silicon solar cell. In the process of manufacturing a PN junction on a silicon wafer, a selective diffusion technology method is adopted, i,e. laser is utilized to heat a position, on which a positive electrode intends to be manufactured, on the surface of the silicon wafer; and under the action of heating, phosphorus in a phosphorus source uniformly adhered on the surface diffuses towards the inner of the silicon wafer, thus a heavy doping zone with smaller sheet resistance is formed at the position on which the positive electrode intends to be manufactured to effectively reduce the sheet resistance of the silicon solar cell, thereby not only being beneficial for increasing the open-circuit voltage of the silicon solar cell; the increase of the open-circuit voltage effectively improves the conversion efficiency of the silicon solar cell, reduces ohmic contact of a metal electrode and the silicon solar cell, thereby reducing the series resistance of the silicon solar cell, and being capable of meeting the purpose of industrialized production better.

The invention provides a front silver paste for a high sheet resistance silicon-based solar cell and a preparing method of the front silver paste. The front silver paste is composed of, by weight, 80% to 90% of silver powder, 0.5% to 6% of glass powder and 5% to 15% of organic carriers. The glass powder is composed of, by weight, 25% to 75% of TeO2, 20% to 55% of PbO and 1% to 20% of Na2O. The organic carriers include resin and organic solvents. The silver paste is suitable for the high sheet resistance silicon-based solar cell and can make good ohmic contact with the high sheet resistance silicon-based solar cell, and therefore the conversion efficiency of the solar cell is greatly improved; meanwhile, the silver paste can keep welding pulling force obtained after high-lead silver paste is sintered on the solar cell by adjusting the content of Na2O, the sintering temperature range is effectively widened, and stability of product performance is ensured.

The invention relates to a biological glass base porous composite material of a degradable mechanical enhanced type and a preparation method thereof. The material takes a biological glass porous stent which comprises macroporous channels and mediated pore channels as matrix. Adjacent macroporous channels are mutually communicated. The internal and external surfaces of the macroporous channels and mediated pore channels are provided with gel layers which are assembled layer-to-layer by the biomolecules with positive and negative charges alternatively. The biological glass matrix is made from the components with the following weight percentage of 16-38 percent of CaO, 0-10 percent of P2O5, 45-80 percent of SiO2, 0-0.1 percent of SrO and 0-22.5 percent of Na2O. The releasing speed of the biological active ions of the biological glass base porous composite material which is similar to the extracellular matrix and is decorated by the layer-to-layer assembly of the charges of different polarity of the biomolecules can be effectively cut and controlled. The walls of the pore channels are beneficial to the adhesion growth of cells. The mechanical strength, the fracture toughness and the machinability are good. And the application of the regeneration treatment on the bone gear injury home position of a stress concentrated part can be satisfied.

The invention relates to a high strength self-lubricating iron-copper powder composite material, a preparation method and application thereof. The composite material is characterized by comprising an iron alloy base body and a copper alloy base body as a surface layer, wherein the iron alloy base body contains Cu, C, Sn, Pb and Fe, and the copper alloy base body contains Ni, C, MoS2, Sn, Fe, Pb and Cu. The preparation method comprises the following steps of: respectively preparing copper alloy layer warm-pressing powder and iron alloy base body warm-pressing powder; filling the warm-pressing powder into a mould and then pressing once to form a green compact; sintering the green compact in the protection atmosphere; and shaping the sintered sintering compact in the mould so that the composite material is prepared. By the invention, the cost of parts can be greatly reduced on the basis of ensuring the use performance of the parts.

The invention relates to lightweight foamed ceramics and a preparation method of the lightweight foamed ceramics. The lightweight foamed ceramics are prepared by the steps as follows: mechanically agitating raw material, curing agent and foam based on a certain ratio, so as to obtain uniform ceramic size; moulding the ceramic size by casting; and curing and drying same at a certain temperature; and finally sintering the dried blank body to obtain the lightweight foamed ceramics. The lightweight foamed ceramics are important for efficiently utilizing the solid waste, reducing the pollution of the industrial solid waste to the environment, and reducing the production cost; the produced lightweight ceramics have the advantages of being more in closed air pores, relatively low in heat conductivity, relatively high in strength, and relatively low in sintering temperature; and the lightweight foamed ceramics are suitable to be applied to the fields of lightweight decorative material, building insulation wall material, sound insulating material, fireproof material and sinking preventing material.

The invention provides a preparation method for preparing low-density oil well cementing cement briquettes by vermiculites. The preparation method comprises vermiculite balling treatment, high-temperature expanding and sintering, dosing, mixing, stirring and size-mixing, die testing and strength test, and is characterized by carrying out stirring and size-mixing for 40s to 50-70wt% of G-grade oil well cement, 20-40wt% of blind-hole hollow glass microspheres with particle size of 10-80mu m, 5 to 7wt% of fly ash with loss on ignition of 1.1%, 1.5 to 2wt% of calcium oxide with purity of 99.9%, 0.5 to 1.0wt% of sodium sulfate and 1 to 3wt% of micro-silicon in a stirrer according to a water cement ratio of 0.5-0.7 (W/C), pouring into two test molds in one group, wherein length, width and height of each test mold are 53mm, 53mm and 53mm respectively, curing for 24h and 48h in a water-bath curing box at the constant temperature of 52 DEG C, immersing for 1h in cold water after de-molding, and then carrying out strength test. Therefore, the performance of the low-density oil well cementing cement briquettes is better than that of floating microspheres.

The invention discloses a doping type spinel lithium manganate electrode material and a preparation method of the doping type spinel lithium manganate electrode material, wherein the molecular formula of the doping type spinel lithium manganate electrode material is LiMn2-x-yMxNyO4; and in the formula, M and N are doping elements and selected from any two of Al, Mg, Cr and Co, and x+y is greater than 0 and less than 0.6. According to the doping type spinel lithium manganate electrode material, two metal elements M and N are used as epiphase dopants for remarkably improving the structure of pure lithium manganate, so that the proportion of trivalent Mn is further reduced, the stability of the structure is increased and the Jahn-Teller effect is restricted, and at the same time, the metal elements M and N are capable of restricting the dissolution of the Mn on the surface of the lithium manganate, so that the cycle performance and the high/low-temperature performance of the lithium manganate are improved; and at the same time, the epiphase doping has the effect of decreasing the doping amount under the condition with same doping effect, so that benefit is brought to reduce the material cost. The spinel lithium manganate electrode material provided by the invention is characterized by being suitable for the high-power lithium cells of electric tools and electric vehicles.

The present invention discloses discloses a composite PTFE membrane comprising an expanded PTFE membrane as substrate and a sintered porous PTFE membrane on top of it. The porous PTFE membrane on top has porous structure with interconnected channels formed with a sintering process that fuses the PTFE fine powders coated on the ePTFE membrane. Furthermore, the present invention discloses a method for forming the composite PTFE membrane.

The invention discloses a method for rapidly preparing high heat conduction Si3N4 ceramic with low cost. The method is characterized in that Si powder is taken as a raw material, ZrO2 powder is taken as a nitridation catalyst, ZrO2-MgO-Re2O3 is taken as a sintering aid, wherein Re2O3 is taken as a rare earth oxide, Si, ZrO2 and MgO-Re2O3 are mixed according to mass fraction and then dried to obtain a Si-ZrO2-MgO-Re2O3 mixing powder; the mixing powder is subjected to a two-step insulation method and a pressureless sintering process to obtain the high heat conduction Si3N4 ceramic; According to the ceramic material, the relative density is higher than 95%, hardness is 8-20 GPa, fracture toughness is 3-8MPa.m<1/2>, bending strength is 200-1000Mpa, and the thermal conductivity is 20-100W.m<-1>,K<-1>. By introducing a ZrO2 catalyst, Si powder nitridation IS accelerated, the introduction of ZrO2-MgO-Re2O3 can improve the densification of Si3N4, and the high heat conduction Si3N4 ceramic can be rapidly prepared with low cost.

The invention provides an NdFeB magnet which comprises, by mass, 29% to 33% of Pr-Nd, 0.97% to 1.5% of B, 0.4% to 0.6% of Dy, 0.2% to 0.8% of Al, 0.6% to 0.8% of Co, 0.01% to 0.5% of Cu, 0.01% to 0.2% of Zr and the balance Fe. The invention further discloses a preparation method of the NdFeB magnet. The method includes the steps that firstly, Pr-Nd alloy, Zr-Fe alloy, B-Fe alloy, Dy-Fe alloy, aluminum, cobalt, copper and iron are molten to prepare an NdFeB cast ingot; secondly, the obtained NdFeB cast ingot is milled into NdFeB powder; finally, the NdFeB powder is sintered into the NdFeB magnet. The NdFeB magnet prepared through the method has a more refined magnet grain size and higher magnet stability.

The present invention provides a method for preparing nano hydroxyapatite/carbon nano tube composite coating by adopting electrophoresis deposition process. Said method includes the following steps: base pretreatment, preparing nano-grade HA and CNTs electrophoresis deposition soliquoid, making the electrophoresis deposition soliquoid undergo the processes of standing still, ultrasonic treatment and centrifugal separation, removing upper layer suspended liquor, making electrophoresis deposition treatment and sintering under the argon atmosphere so as to obtain the invented target product.

The invention discloses a nano-titania-toughened high-density aluminum nitride-silicon carbide composite circuit board substrate material. According to the material, aluminum nitride powder and silicon carbide powder are used in a mixed manner, so that the material has high heat conduction and environment-friendliness; a mixed solvent prepared from quaternary ammonium salt ionic liquid, anhydrous ethanol and the like has better wettability to composite powder compared with the traditional organic solvents, and the compatibility among powders is good, so that a stable interpenetrating network structure can be formed, and the utilization ratio of raw materials is increased; slurry is good in fluidity and easy to shape, so that the sintering temperature and thermal stability of prepared preforms are better; nano-titania has good affinity, so that the material has the effects of certain reinforcing and toughening, sintering temperature lowering, substrate density improving and the like; and due to sintering auxiliaries and other raw materials, prepared substrates are better in heat conductivity, easy in sintering shaping and high in finished product rate, are thin, tough and durable and can be extensively used as a variety of circuit board substrates.