46results about How to "Improve medium temperature strength" patented technology

The invention provides a sliding brick and a preparation method thereof. The sliding brick is prepared from a mixture through molding and sintering, wherein the mixture comprises plate-shaped corundum, fused spinel, fused mullite, alumina, silicon carbide, silicon, aluminum and boron carbide. According to the invention, plasticity of both aluminum and silicon is combined together, which is favorable for improvement of density and strength of the sliding brick; meanwhile main materials like plate-shaped corundum are used, so the sliding brick has good high temperature performance, erosion resistance and thermal shock resistance. In the process of preparation of the sliding brick, light roasting or high temperature sintering is employed, so the prepared sliding brick has high hot strength and erosion resistance and good cold strength, anti-scouring performance and oxidation resistance.

The invention relates to a novel RH gunning refractory belonging to the refractory material field. The gunning refractory comprises the following raw materials in weight percent: 50-60% of fused magnesite crude powder, 15-30% of fused magnesite fine powder, 10-255% of chrome ore, 0.5-2% of slaked lime, 1-5% of light calcium carbonate, 1-4% of sodium hexametaphosphate, 2-55% of borax, 2-4% of silica powder, 0.5-4% of sodium tripolyphosphate and 0.005-0.1% of carboxymethylcellulose; and the raw materials are evenly mixed in a stirring device to obtain a finished product. The RH gunning refractory prepared from the raw materials provided by the invention is low in production cost, resistant to erosion and good in impermeability; an RH insert tube after being subjected to gunning maintainmentcan be used more than 85 times and the RH insert tube can be used for 5-6 furnaces after every time of gunning maintainment; the service life of the RH insert tube is obviously prolonged and the production efficiency is greatly improved; and in the use process, no harmless gas gives out, no peculiar smell is produced and no thick smoke is generated; and therefore the novel RH gunning refractory completely meets specified environmental indexes and utilization requirements..

The invention discloses a preparation method for a special casting material of a ferronickel rotary kiln discharge opening. The special casting material is prepared from the following materials in percentage: 40-80% of material bauxite or/and adamantine spar aggregate, 5-20% of electric smelting mullite or/and adamantine spar fine powder, 3-10% of alumina micro powder, 3-10% of silicone micro powder, 1-8% of pure calcium aluminate cement and 3-30% of calcium zirconate or/and zirconite. The preparation method has the advantages that corrosion resistance, thermal shock resistance and performance in moderate-temperature intensity can be improved greatly; utilization requirements of the ferronickel rotary kiln discharge opening are met. Compared with the conventional casting materials used by cement kiln discharge openings, the service life of the casting material can be prolonged by three months.

The invention discloses a silica sol-combined mullite perfusion material adapted to rapid repair of an industrial furnace, which belongs to the refractory material technical field. The perfusion material comprises the following raw materials by weight: 50-60% of mullite granules, 10-20 % of mullite powder, 5-10% of white alundum powder, 4-15% of alpha-active alumina micro powder, 0.6-1.0% of magnesium oxide powder, 0.5-0.7% of dextrin, 10-16% of silica sol and 1-2% of dispersing alumina. The silica sol-combined mullite perfusion material is characterized in that the silica sol is individually packaged; other components are weighted according to ratio and mixed through mechanical stirring to uniform aggregates in a dry state; on construction site, the individually packaged silica sol and uniform aggregates in the dry state are weighted according to ratio, and uniformly mixed and stirred and pumped for construction. The perfusion material has the advantages of excellent physical and chemical property and good application property, pumping for construction can be used, manpower and material resources can be saved, rapid repair requirement for various industrial furnaces can be satisfied, and the perfusion material is the excellent repair refractory material with strong adaptability.

The present invention relates to one kind of periclase-silicon carbide composite material and its preparation. The technological scheme includes mixing fused magnesia or sintered magnesia in 60-90 wt%, silicon carbide in 10-40 wt% binding agent in 3-8 wt%, hexamethine tetramine as curing agent in 0-1 wt% through stirring; pressing and forming the mixture; and stoving at 110-350 deg.c for 2-24 hr to prepare the composite material. The prepared composite material has high smelting point, high heat conductivity, and especially self-protecting oxidation characteristic, which is that the oxidized SiC forms one layer of protecting silica film to protect the inside from being further oxidized. The present invention substitutes SiC for graphite to raise the antioxidant performance of material greatly and the material has raised medium temperature strength, so that the material may be used as lining material for metallurgical furnace and container.

An environment-friendly magnesian dry material comprises sintered magnesia, fused magnesia, calcium forsterite, a binding agent, aluminum hydroxide micro powder, a high-temperature sintering agent, anexpanding agent, floating beads and bentonite in a mass ratio of (60-75): (20-30): (8-10): (15-25): (8-12): (2-4.5): (1-2): (0.5-1.5): (0.8-1.2). According to the invention, the proportion of each component of the dry material is optimized; by adopting the environment-friendly binding agent, the problem that the binding agent is decomposed into toxic and harmful substances under a high-temperature condition can be effectively solved, the dry material is more energy-saving and environment-friendly, the hardness requirement of the dry material in the using process can be ensured on the premisethat the dry material has no pungent smell in the using process and is more beneficial to the production environment, and the scouring resistance of the dry material is ensured.

The invention relates to tundish magnesium calcium ladle cover casting materials. The tundish magnesium calcium ladle cover casting materials comprise the following components in percentage by weight:20-40wt% of magnesium sand granules, 20-40wt% of magnesium calcium sand granules, 5-15wt% of quick lime granules, 10-20wt% of a magnesium sand fine powder, 0.5-3wt% of an organic magnesium compound,1-6wt% of organic calcium, 2-6wt% of a thermoplastic micro powder, 2-8wt% of a magnesium oxide micro powder and 0.1-0.2wt% of a water reducing agent. The invention further relates to a method for preparing the tundish magnesium calcium ladle cover casting materials. According to the tundish magnesium calcium ladle cover casting materials and the preparation method thereof disclosed by the invention, the heat shock stability of fireproof materials is improved, besides, dissipation of heat quantity is effectively reduced, and favorable heat preservation properties and favorable thermal shock resistance of the materials are guaranteed; and when the tundish magnesium calcium ladle cover casting materials are applied to high-quality steel continuous casting tundishes, the temperature of a housing of a tundish ladle cover can be reduced by 10% or above averagely, and the average service life reaches 15 times or above.

The invention discloses a green and environment-friendly magnesia spinel gunning mix for a converter, a preparation method of the green and environment-friendly magnesia spinel gunning mix and an application of the green and environment-friendly magnesia spinel gunning mix in converter maintenance. The magnesia spinel gunning mix comprises the following raw materials in parts by mass: 45-80 parts of a magnesia spinel reclaimed material, 5-35 parts of a magnesia material, 4-14 parts of a magnesia binding agent, 1-5 parts of a phosphate binding agent, 2-5 parts of slaked lime micro powder, 0.05-0.5 part of a thickening agent and 0.05-0.5 part of an anti-explosion agent. The gunning mix does not contain asphalt and resin, is environment-friendly, and has excellent adhesion and molten steel corrosion resistance by introducing the magnesium spinel reclaimed material and adopting the magnesium binding agent. The waste refractory materials are recycled, the green and environment-friendly development requirement is met, the service life of the gunning material is guaranteed, the steelmaking cost is reduced, and application and popularization are facilitated.

The invention relates to a novel high strength refractory brick and a production method thereof. The novel high strength refractory brick comprises, by weight, 50-70 parts of corundum, 20-40 parts of mullite, 1-10 parts of first grade clay, and 1-10 parts of an ultrafine powder binder, and also comprises arched CrNi steel fibers, and 100Kg of the CrNi steel fibers are added to 1m<3> of the refractory brick. Compared with refractory bricks in the prior art, the novel high strength refractory brick provided by the invention has the advantages of high refractoriness and high flexural strength.

The invention relates to a preparation method of a large solid quartz ceramic material and belongs to the technical field of quartz ceramic products. The preparation method comprises the following steps: preparing a mixed material: weighing the following substances in percent by mass: 15-35% of quartz coarse particles, 20-40% of quartz fine particles, 0.99-5.66% of a bonding agent, 15-30% of quartz fine powder, 8-20% of quartz micropowder and 8-15% of spherical quartz micropowder, and mixing the substances uniformly to form the mixed material; isostatic compaction: filling a rubber mold with the mixed material and vacuumizing the mold, and carrying out compression moulding at an isostatic press of 80-150 MPa to form a blank; and sintering process: sintering the blank in the step 2 according to a firing system, and carrying out furnace cooling to room temperature after fire stopping. The preparation method is scientific and reasonable and simple and feasible and the prepared quartz ceramic material is good in microstructure uniformity and has the characteristics of low porosity, high volume density and high constant temperature pressure resistance.

The invention belongs to the technical field of metallurgical refractory matters and relates to an additive for stemming for inhibiting iron notch splash. The additive comprises the following components in parts by weight: 1-3 parts of silicon metal, 0.4-0.6 part of boron carbide, 2-8 parts of asphalt, 0-5 parts of silicon nitride and 2-8 parts of kyanite. When the additive for stemming for inhibiting iron notch splash disclosed by the invention is added into the stemming, a proper amount of glass phase components can be generated at high temperature, and possible cracks generated in an iron notch channel can be plugged by the glass phase contacted with molten iron under the condition that the high-temperature performance is not influenced, so that splash caused by gas channeling is effectively prevented. Moreover, the additive has the advantages of proper micro expansion effect, medium and high temperature strength, slag iron erosion resistance and oxidation resistance.