212results about How to "Fast sintering" patented technology

Aerogel composite materials having a lofty fibrous batting reinforcement preferably in combination with one or both of individual short randomly oriented microfibers and conductive layers exhibit improved performance in one or all of flexibility, drape, durability, resistance to sintering, x-y thermal conductivity, x-y electrical conductivity, RFI-EMI attenuation, and/or burn-through resistance.

The invention relates to (HfTaZrTiNb) C high-entropy ceramic powder and preparation methods of the high-entropy ceramic powder and high-entropy ceramic blocks. Five-face centered cube (FCC) carbonizedpowder is made into ceramic powder through a high-energy ball milling method, then a discharging plasma method is adopted to realize preparation of the high-entropy ceramic blocks, and quick sintering of ceramic within a temperature range of 1700-2350 DEG C can be realized to obtain high-entropy ceramic with single-phase-face centered cube (FCC) structure. The preparation method of (HfTaZrTiNb) Chigh-entropy block ceramic is solved; the high-entropy ceramic with the FCC structure is finally obtained by strictly controlling parameters of a discharging plasma sintering furnace or a hot press furnace and characterizing XRD, so that the ceramic material system is enriched.

The invention belongs to a preparation technique of a copper-based composite material, and discloses a method for preparing a diamond-copper composite material by virtue of metallization of a surface. The method comprises the following steps of: mixing diamond micropowder with copper powder and powder formed by strong carbide elements, wherein the particle size of diamond is 80-300mu m, the content of the strong carbide elements is 1-10wt%, and the mass fraction of the copper powder is 20%-85%; blending the obtained mixed powder for 10-90 minutes at the temperature of 1050-1150 DEG C, and then cooling along with a furnace; sieving to select the powder with the particle size of 80-300 mu m; mixing the mixed powder with the copper powder again, wherein the mass fraction of the copper powderis 40%-95%; quickly heating the mixed powder material to 850-950 DEG C for sintering at the sintering pressure of 30-50MPa; and then, cooling the obtained product to a room temperature along with thefurnace to obtain the diamond-copper composite material. The method for preparing the diamond-copper composite material has the advantages that the operability of the metallization of the surface of the diamond is strong; the process is simple; the wetting property of a matrix and an enhancer in the prepared diamond-copper composite material is improved greatly; and as an electronic encapsulatingmaterial, the composite material has better comprehensive property, wherein the thermal conductivity is up to 672 W/m.K, the thermal expansion is lower than 7.6 mu m/m. DEG C, and the compactness reaches above 96%.

The present invention relates to a preparation method of boron carbide ceramics. In particular, the preparation method comprises the following steps: first, boron powder and carbon powder are weighed and mixed with the molar ratio of boron and carbon equal to 0.5 to 22.5; secondly, the powder prepared in the first step is arranged in a die and transmitted to discharging plasma sintering equipment for sintering, and the temperature is raised to be between 1300 and 2200 DEG C under the vacuum conditions; thirdly, the die is taken out from the discharging plasma sintering equipment and cooled to be at the room temperature; then the die is drawn away and thus the final product is prepared. In the preparation method, the direct synthesis and densification of boron carbide are completed in one step; the powder is sintered under the vacuum conditions; and the prepared boron carbide ceramics has the advantages of high purity, variety in the ratio of boron and carbon, and high hardness.

The invention relates to a stemming, and especially relates to a stemming used in a non-blast-furnace taphole, wherein the non-blast-furnace taphole is used in molten iron smelting with a smelting reduction method. The stemming comprises: corundum 30-48 wt%, silicon carbide 7-20 wt%, a carbonaceous material 15-24wt%, sialon 10-20wt%, magnesium aluminate spinel 3-9wt%, kaolin 8-14 wt%, silicon-aluminum alloy 2-7wt%, and a tar and resin composite binding agent accounting for 16-24% of the total weight of the above materials. The stemming has good opening performance and mud-making performance. The stemming can resist erosion and corrosion of high-temperature high-pressure molten iron and slag. Especially, the stemming can resist corrosions of high-sulfur high-silicon molten iron and FeO-rich slag. When in use, a taphole depth is stable. The stemming is applied on a taphole of a smelting reduction furnace used in iron making.

The invention relates to a plastic forming technique and a powder metallurgical technique, in particular to a nano crystal tungsten based alloy block material and a method for preparing the same. The block material comprises the following components in weight percentage: 86 to 88 percent of W, 6.5 to 7.5 percent of Ni, 2.5 to 3.5 percent of Fe, 2 to 4 percent of Mo and 1 to 2 percent of Co. The preparation method comprises the following steps: Fe-Co-Ni and W-Mo after dry mixing are ball milled in advance respectively until the Fe, Co and Ni completely form solid solution, and tungsten phase crystal grain is thinned to below 100nm; the Fe-Co-Ni and W-Mo are subjected to high energy ball milling until the Fe-Co-Ni is evenly distributed around the W-Mo crystal grain; and the discharge plasma rapid sintering is adopted. The nano crystal tungsten based alloy block material has the advantages of reasonable formula, even and thin microstructure, nearly full compact, higher hardness and tensile strength and good specific elongation, and the method for preparing the block material effectively improves the mechanical performances of the sintering material.

Belonging to the technical field of refractory materials, the invention relates to taphole stemming used for oversize blast furnaces over 4500m<3>. The taphole stemming used for oversize blast furnaces comprises by weight: 25-50% of brown corundum, 5-20% of silicon carbide, 7-25% of ferro-silicon nitride, 15-30% of a composite carbon material, 5-15% of kaolin, 3-7% of composite refractory material micropowder, and 1-5% of composite metal powder. The stemming is prepared by the steps of: conducting weighing and burdening according to the above ratio of various raw materials, mixing them well and adding a coal tar binder accounting for 15-25% of the total weight of the additionally added dry materials, then conducting rolling and mulling so as to obtain a mud material. The stemming of the invention has good comprehensive performance, stable taphole depth, long tapping time, good erosion and scouring resistance, as well as good construction performance.

The invention relates to the technical field of high-performance ceramics, in particular to high-entropy ceramic powder and a preparation method thereof, and a high-entropy ceramic block. According tothe invention, the high-entropy ceramic powder and the high-entropy ceramic block are prepared by adopting a coprecipitation method; required experimental equipment is simple; operation is easy; large-scale production is facilitated; the sintering temperature of the high-entropy ceramic can be remarkably reduced; rapid sintering of the ceramic is achieved within a temperature range of 1000-1400 DEG C; and the high-entropy ceramic with a perovskite structure is obtained.

The present invention provides one kind of high calcium low iron magnesia material as refractory ramming material and its preparation process. The present invention has materials including light burnt magnesia powder, light burnt dolomite powder, fused magnesia, superfine fused magnesia powder, iron oxide scale as rolling waste, iron oxide powder as steel making side product, and diesel oil. The present invention has high heat resistance, high load softening performance, high breaking strength, high heat shock performance, high slag corrosion resistance and thin furnace bottom sintered layer. It is especially new steel making process, and can maintain excellent performance at high temperature.

The invention discloses a hot ultrasonic sintering method and device of nano silver/graphene composite ink. According to the method, nano silver powder and graphene are dispersed into a mixed organic solvent; the nano silver/graphene composite ink with the mass percent of 0.01%-90% is prepared; the high-viscosity nano silver/graphene composite ink is extruded from a rubber sleeve through air pressure; scribbling is carried out on a flexible substrate through a dispensing head to form the flexible substrate with a conductive circuit; the dried flexible substrate with the conductive circuit is put between two layers of PDMS protective plastic, and pressure is applied to reach a required value of 3-30MPa; the heating temperature is 60-160 DEG C; hot-pressing pre-sintering is carried out under the conditions of 3-30MPa and 60-160 DEG C for 1-10 minutes; hot ultrasonic sintering is carried out under the conditions of 3-30MPa and 60-160 DEG C for 1-10 minutes; solid-state diffusion between nano silver/graphene is achieved through the effects of ultrasound, pressure and temperature; and a flexible circuit with good conductivity and mechanical bending property is prepared.

The present invention discloses a rapid sintering method for a dental zirconium oxide ceramic. The rapid sintering method is characterized in that a rapid sintering furnace with a heating rate of 120 DEG C/min and designed by our company is used, a 3% mol Y stabilized zirconium oxide tooth material commonly used in dentistry and a 5% mol Y stabilized zirconium oxide tooth material commonly used in dentistr are used as raw materials, and the sintering method is controlled to adapted to the materials, such that the teeth can achieve the same effect as the effect obtained by using the traditional 7-15 h sintering method commonly used in dentistry after the 3% mol Y stabilized zirconium oxide and the 5% mol Y stabilized zirconium oxide are completely sintered within 0.5-1.5 h, wherein the transparency of the material cannot be reduced.

The invention discloses a spark plasma sintering system which comprises a sintering furnace and a control system connected with the sintering furnace. The control system comprises a displacement/pressure control system, an atmosphere control system, a vacuum control system and a temperature control system. The sintering furnace comprises a pressurization device and an impulse current generator. The pressurization device comprises an upper pressing head and a lower pressing head which are correspondingly arranged, upper electrodes and lower electrodes which are arranged on the upper sides and the lower sides of both the upper pressing head and the lower pressing head respectively, a sintering die arranged between the upper pressing head and the lower pressing head and a water cooling vacuum chamber arranged on the outer side of the sintering die, and the impulse current generator is connected with the upper electrodes and the lower electrodes. The spark plasma sintering system is good in forming effect, the forming process is controlled accurately, and the product quality is greatly improved.

The invention refers to a method for preparation of zirconium diboride block material. The method is about a discharging plasma sinter high-integrity zirconium diboride block material, the character is lies in it includes steps as follows: directly posting coated format ZrB2 in graphite mould, and then putting mould in discharging plasma sintering furnace, applying axial pressure of 10- 50MPa, adopting vacuum condition or interia atmosphere which vacuum degree is less than 10Pa, sintering in sintered temperature of 1600- 2200Deg C, heating-up with rate of 50-500Deg C/min, heat preserving for 1-30min, cooling under 1300Deg C with cooling rate of 10-100Deg C/min, finally furnace cooling to room temperature, getting high degree of compactness zirconium diboride block material. The produced zirconium diboride block materials have high degree of compactness, hardness, high-temperature strength and oxidation resistance capability.

The invention discloses a manufacturing method of a high-precision and high-reliability NTC thermistor chip, which comprises the following steps of: 1) weighing corresponding metal oxides according to a chemical formula Mn3-x-y-zNixFeyCozQtO4, mixing, ballmilling, and roasting into thermal sensitive ceramic pre-powder A, 2) uniformly mixing the thermal sensitive ceramic pre-powder A and nano thermal sensitive ceramic pre-powder B into a mixture, preparing the mixture into slurry, 3) filter-pressing and forming the slurry to a green body, drying and isopressing the green body, 4) conducting microwave sintering on the body obtained in Step 3), and 5) slicing an obtained sinter cake, placing an electrode and conducting heat treatment in a shielding gas atmosphere, wherein the mass percent of the B in the mixture is 5-75wt%, and the solid content of the slurry is 70-80wt%. The 1% yield of the prepared chip is improved greatly, and the reliability is also improved obviously.

A device for sintering transparent ceramics by induction heating comprises a double-layer stainless steel furnace mantle with an intermediate course where cooling water can pass and a bracket supporting the furnace mantle, wherein the upper and lower walls of the furnace mantle are provided with gas ports used when atmosphere sintering, a tray is installed at the center of the bottom of the internal wall of the furnace mantle, a quartz barrel is disposed on the tray, a ceramic sample to be sintered is disposed in a heating element, and the heating element is embedded in a heat insulating material inside the quartz barrel; the quartz barrel is covered with a quartz glass cover with a round hole at the center; an induction coil is installed outside the quartz barrel; one end of a tungsten-rhenium thermoelectric couple is penetrated into the quartz barrel passing through the round hole of the quartz glass cover and is tightly close to the external wall of the heating element; a main gas path is formed by a first baffle valve, a molecular pump, a second baffle valve and a mechanical pump connected gradually at the pumping hole of the upper side of the furnace mantle via pipelines, and pipelines directly communicated with the main gas path between the furnace mantle and the first baffle valve through the third baffle vale by the mechanical pump through the pipelines are gas bypasses.

The invention belongs to the field of high-entropy ceramic materials and particularly discloses a method for preparing perovskite type composite oxide high-entropy ceramic through hot pressed sintering. The A position of the perovskite type composite oxide high-entropy ceramic is occupied by Sr, and the B position of the perovskite type composite oxide high-entropy ceramic is composed of Zr, Sn, Ti, Hf elements and any one selected from the group consisting of Nb, Ta, Mn and Tb elements in a nearly equal molar ratio. The Sr(Zr<0.2>Sn<0.2>Ti<0.2>Hf<0.2>M<0.2>)O<3> (wherein M is Nb, Ta, Mn or Tb) composite oxide high-entropy ceramic material is prepared by adopting a hot pressed sintering technology, and the prepared ceramic material is submicron-sized in crystal grain, compact in structure,simple in preparation process and short in period.