1716 results about "Zircon" patented technology

Isopipes for use in making sheet glass by a fusion process are provided which exhibit reduced sag. The isopipes are composed of a zircon refractory which has a mean creep rate (MCR) at 1180° C. and 250 psi and a 95 percent confidence band (CB) for said mean creep rate such that the CB to MCR ratio is less than 0.5, the MCR and the CB both being determined using a power law model. The zircon refractory can contain titania (TiO2) at a concentration greater than 0.2 wt. % and less than 0.4 wt. %. A concentration of titania in this range causes the zircon refractory to exhibit a lower mean creep rate than zircon refractories previously used to make isopipes. In addition, the variation in mean creep rate is also reduced which reduces the chances that the zircon refractory of a particular isopipe will have an abnormally high creep rate and thus exhibit unacceptable sag prematurely.

The invention discloses an environment-friendly metal surface treating agent and a using method thereof. The treating agent comprises fluoride, zircon salt, silane, silicon dioxide, accelerating agent, dispersing agent and stabilizing agent. A conversion coating having the advantages of being compact and even, strong in corrosion resistance and excellent in adhesive force of the coating is respectively formed on the metal surface of steel and zinc; a treatment method of the metal surface treating agent is simple and is operated at the normal temperature; the original phosphating treatment equipment can be used without any change; and strong acid and strong base are not used as the treating agent; therefore, the environment-friendly metal surface treating agent is safe in production without emission, and is the best substitute product of the phosphating treatment technique and an energy-saving type environment-friendly product.

A method of forming high strength glass fibers in a refractory lined glass melter is disclosed. The refractory fined melter is suited to the batch compositions disclosed for the formation high modulus, and high-strength glass fibers. The glass composition for use in the method of the present invention is up to about 70.5 Weight % SiO2, 24.5 weight % Al2O3, 22 weight % alkaline earth oxides and may include small amounts of alkali metal oxides and ZrO2. Oxide based refractories included alumina, chromic oxide, silica, alumina-silica, zircon, zirconia-alumina-silica and combinations thereof. By using oxide based refractory lined furnaces the cost of production of glass fibers is substantially reduced in comparison with the cost of fibers using a platinum lined melting furnace. Fibers formed by the present invention are also disclosed.

A method for inlaying the diamond or zircon onto jadeite includes such steps as blanking, drilling one or more blind or through holes, installing inlaying nail, cutting the inlaying nail, inlaying the diamond or zircon to said inlaying nail, wrapping the edge of inlaid diamond or zircon by an expanding sleeve made of gold alloy or stainless steel, grinding and polishing.

The invention discloses a method for producing special rutile type titanium white powder for power coating, which comprises the following steps of: preparing slurry of which titanium dioxide concentration is 300 to 400g / l by using bleached metatitanic acid, and adding a calcining auxiliary agent into the slurry; filtering the obtained metatitanic acid, then calcining solid, and grinding the solidto obtain a primary product; preparing titanium dioxide slurry of which titanium dioxide concentration is 650 to 850g / l by using the obtained primary product, adding a wetting agent into the titaniumdioxide slurry, and performing dispersion and grinding; heating the obtained titanium dioxide slurry to between 40 and 90 DEG C, adding dispersant, zircon salt or titanium salt, silicon salt and aluminum salt into the slurry in turn, adjusting the pH value to between 5 and 9, ageing the mixture, and adjusting the pH value to between 7 and 8; and then filtering, washing and drying the mixture, treating the dried product by an organic surface treatment agent, and vaporizing the product to obtain the rutile type titanium white powder. Compared with the prior art, the rutile type titanium white powder obtained by the method has the properties of stable crystal lattice, good dispersion, heat and yellowing resistance, and good oily whiteness, reducing power, covering power and weather resistance and the like; the appearance and properties of the rutile type titanium white powder are close to that of the rutile type titanium white powder prepared by a chlorination process; and the productionmethod has the advantages of easily obtained process raw materials and stable process control.

An apparatus for forming a glass sheet with reduced zircon inclusions in the glass sheet is disclosed. In one embodiment, the apparatus comprises heating elements distributed vertically between the weirs of a forming wedge and the root of the forming wedge, and wherein a thermal barrier is disposed between adjacent heating elements. A method of using the apparatus is also disclosed.

Ion exchangeable glasses having coefficients of thermal expansion (CTE) at least about 90×10−7 ° C.−1. The glasses undergo rapid ion exchange, for example, in a molten KNO3 salt bath to a depth of layer of greater than 30 microns in less than 2 hours at temperatures of 370° C. to 390° C. When ion-exchanged to a depth of layer between 30 to 50 microns, the glasses exhibit a Vickers median / radial crack initiation threshold exceeding 30 kilograms force (kgf). The glasses are fusion formable and, in some embodiments, compatible with zircon.

The invention relates to a chromium-free composite passivator for a hot-dip galvanized steel sheet. The passivator is prepared from the following raw materials in percentage by weight: 2.20-2.30% of water-base resin, 2.60-2.65% of main salt compound, 0.10-0.15% of organic silane, 0.07-0.09% of sulfate, 0.11-0.13% of inorganic zircon salt, 0.09-0.12% of inorganic acid and the balance of water. A preparation method of the passivator comprises the following steps: firstly, dissolving the organic silane in water; stirring till the organic silane is fully dissolved and adding the main salt compound; after the main salt compound is dissolved, adding the inorganic acid to measure the pH value; then, adding the sulfate and the inorganic zircon salt in the stirring state; after the sulfate and the inorganic zircon salt are fully dissolved, adding the water-base resin; stirring till the water-base resin is fully dissolved; adjusting the pH value to 3-4 by virtue of ammonium water; and standing for later use. An application method of the passivator comprises the following steps: firstly, degreasing the hot-dip galvanized steel sheet by virtue of an alkaline degreaser during use; then, respectively washing by using tap water and deionized water; and after drying, coating the composite passivator on the surface of the hot-dip galvanized steel sheet. The passivator provided by the invention is free from chromium and non-toxic and harmless. The thickness of a passivation film can reach 8-1.0mg / m<2>, and the corrosion resistance is close to that of a hexavalent chromium passivating liquid.

The invention relates to a protective coating for a refractory material member of an ingot mold for continuous casting of metals, especially of steel, which consists of a dispersion of particles in a solvent, said particles including essentially boron nitride and at least one of the following metal oxides: zircon, zirconia, alumina and silica, the boron nitride representing between 20 and 50% by weight of said particles.

An ultracapacitor or hybrid capacitor includes an electrically non-conductive rigid or semi-rigid porous honeycomb structure (12) having cells extending along a common direction and having an average density per unit area within in a plane perpendicular to the common direction exceeding 15.5 per square centimeter, desirably formed of a material that is stable at temperatures of 300° or more, such that high temperatures processing can be used to help ensure high purity of the final product. The material may desirably be an oxide or non-oxide ceramic, such as cordierite, silicon nitride, alumina, aluminum titanate, zircon, glass, or glass-ceramic.

The invention relates to a nickel-based welding electrode which comprises the following component by weight percent (wt%): 50.0-68.0% of Ni, 18.0-23.0% of Cr, 6.0-11.0% of Mo, 3.0-6.0% of Nb, 2.50-9.00% of Fe, 0.01-0.1% of C, 0.10-1.00% of Mn, 0.010-0.10% of Si, 0.015% of S or less, 0.015% of P or less, 0.01-0.10% of Cu, 0.003-0.010% of Co and the balance of impurities. The coat of the nickel-based welding electrode comprises the following components by weight percent of the welding core: 12-18% of marble, 10-15% of fluorite, 12-18% of barium carbonate, 5.0-6.4% of rutile, 3.5-5.0% of ferroniobium, 3.3-4.5 of chromium metal powder, 0.45-0.65% of sodium carbonate, 0.45-0.65% of electrolytic manganese and 1.3-1.8% of zircon sand, and the adhesion agent is 10-20% of the total weight of the power. The nickel-based welding electrode is prepared by mixing, wrapping mixture on the welding core and baking at low and high temperature. The nickel-based welding electrode disclosed by the invention is used for nickel-chromium-molybdenum alloy steel welding, ensures that the excellent mechanical properties, the excellent corrosion resistance, the excellent thermal crack resistance and the hightensile strength of the welding seam match with those of the base material, has good welding process performance, guarantees attractive molding and can be used for the welding of the steel (with 9% of Ni) working at low temperature.

The invention discloses a method for determining the U-Pb age of a zircon sample. The method comprises the steps as follows: the zircon sample and a standard substance are made into a sample target; solid sol is obtained through laser ablation; the solid sol is loaded in a multi-receiving inductive coupled plasma mass spectrograph ion source (plasma) for ionization, and primary ions are obtained; the primary ions pass through an electric field and a magnetic field of a mass spectrograph to realize dual-focusing of energy and direction and arrive at an ion detection system; the original U-Pb ratio of the primary ions of the zircon sample and the zircon standard substance is detected and calculated; the original U-Pb ratio of the zircon sample is corrected by using the standard U-Pb ratio of zircon, and the corrected U-Pb ratio of the zircon sample is obtained; the U-Pb age of the zircon sample is calculated by using the corrected U-Pb ratio. The method has high precision and high sensitivity, has the low sample content requirement, has small ablation depth, and can be used for spatial high-resolution U-Pb age determination of zircon with the ablation diameter smaller than 10 mum.

The invention discloses a special castable for a kiln outlet, which belongs to the field of refractory materials. According to the invention, the special castable comprises the following components in percentage by weight: 8-25% of silicon carbide, 10-30% of andalusite, 20-35% of corundum, 5-15% of spinel powder, 5-10% of zircon mullite powder, 1-5% of zirconium diboride, 1-5% of silicon nitride,5-15% of alumina micropowder, 3-6% of pure calcium aluminate cement, 0.5-1% of explosion-proof fiber and 0.06-0.2% of sodium tripolyphosphate, which is an additive. By using the special castable for the kiln outlet, disclosed by the invention, the phenomenon of poor wear resistance, block falling and the like in the kiln outlet can be effectively improved; the service life of the cement kiln outlet can be largely prolonged; and the special castable for the kiln outlet, disclosed by the invention, has the advantages of high temperature resistance, heat shock resistance, wear resistance, high strength, irreversible micro expansion and the like.

A dry refractory composition having superior insulating value. The dry refractory composition also may have excellent resistance to molten metals and slags. The composition includes filler lightweight material, which may be selected from perlite, vermiculite, expanded shale, expanded fireclay, expanded alumina silica hollow spheres, bubble alumina, sintered porous alumina, alumina spinel insulating aggregate, calcium alumina insulating aggregate, expanded mulllite, cordierite, and anorthite, and matrix material, which may be selected from calcined alumina, fused alumina, sintered magnesia, fused magnesia, silica fume, fused silica, silicon carbide, boron carbide, titanium diboride, zirconium boride, boron nitride, aluminum nitride, silicon nitride, Sialon, titanium oxide, barium sulfate, zircon, a sillimanite group mineral, pyrophyllite, fireclay, carbon, and calcium fluoride. The composition also may include dense refractory aggregate, which may be selected from calcined fireclay, calcined Chamotte, a sillimanite group mineral, calcined bauxite, pyrophyllite, silica, zircon, baddeleyite, cordierite, silicon carbide, sintered alumina, fused alumina, fused silica, sintered mullite, fused mullite, fused zirconia, sintered zirconia mullite, fused zirconia mullite, sintered magnesia, fused magnesia, sintered spinel, and fused spinel refractory grog, a heat activated bonding agent, and a dust suppressant.

The invention discloses a method for evaporative pattern precise composite casting. The method comprises the following steps: making a mould by polystyrene foam to form a casting system; coating a surface modifying agent on the surface of the mould; preparing a mould shell including a surface layer mould shell, a transitional layer mould shell and a back layer mould shell; taking the mould out after placing the mould in a pre-wetting agent for 2 to 3s, dipping the mould in a container filled with surface layer coating, turning the mould so as to evenly coat the mould, sprinkling zircon sand on the mould, and drying the mould for 4 to 6h to prepare a surface layer mould shell; dip-coating the surface layer mould shell by a transitional layer coating, sprinkling and drying the sand for 8 to 12h; preparing the transitional layer mould shell and the back layer mould shell by the similar method; sealing pulp by the back layer coating, and drying for 14 to 18h; roasting the mould at a temperature of between 950 and 1,050 DEG C, and keeping warm for 30 to 60min; and pouring the molten metal in the mould shell to form a casting. The method has the advantages of preparing the metallic mould without the conventional precise casting, saving processing time, lowering cost and simultaneously ensuring the product quality.

The invention discloses a special pouring material for a kiln opening and belongs to the field of a refractory material. The special pouring material comprises the following components by weight percent: 10-25% of silicon carbide, 15-30% of andalusite, 20-35% of corundum, 5-15% of spinel powder, 5-10% of zircon mullite powder, 5-15% of aluminum oxide micro powder, 3-8% of silicon micro powder, 2-5% of pure calcium aluminate cement, and 0.5% and 0.2% of anti-explosion fibers and sodium tripolyphosphate serving as additives. The special pouring material is capable of efficiently improving the wear resistance and avoiding the hot peeling phenomenon of the cement kiln coal injection pipe, has the characteristics of high temperature resistance, heat vibration resistance, wear resistance, high strength, irreversible micro inflation, and the like, and is capable of greatly prolonging the service life of the cement kiln coal injection pipe.

The invention relates to a method for preparing a lanthanum zirconic acid powder, which belongs to the preparation field of ceramic powder used for high temperature heat barrier. The method uses lanthanum oxide or lanthanum soluble salt and zircon salt for respectively preparing the solutions containing La<3+> and Zr<4+>; the two solutions are mixed and dropped into a precipitator (or the precipitator is dropped into the mixing solutions) under continual stirring to obtain precipitate; and the precipitate are washed with a plurality of times, then dried, ground and finally calcined at certain temperature to obtain La2Zr2O7 of defect fluorite structure or pyrochlore constitution. Compared with the existing universal solid reaction process, the method lowers the synthesis temperature by 500-700 DEG C. The heat-insulating property (heat diffusivity) of the obtained power is reduced by about 50 percent compared with YSZ, and reduced by about 40 percent compared with the lanthanum zirconic acid powder obtained by the solid reaction process. The method solves the problems of overhigh heat diffusivity, severe sinter and phase change inefficiency in the existing ceramic materials used for the coating of high temperature heat barrier.

The invention relates to a paint used in large casting element and relative production, wherein said paint is alcohol-base zircon powder casting paint, which contains zircon at 62-75%, lithium-base at alta-mud 1-3%, deionized water at 1-3%, modified almasilate at 1-3%, nanometer clay at 0.15-0.8%, alumind at 0.020-0.08%, soluble polyester resin at 0.2-1.2%, polyvinyl butyral (PVB) at 0.1-0.8%, abietyl at 0.6-3%, industrial alcohol at 15-25%, alcohol isopropylicum at 1-5%, and aromatic solvent oil at 150#1-5%. The inventive product has high fire resistance, etc.

The invention discloses a flux-cored wire for austenitic stainless steel welding. The flux-cored wire consists of a flux core and an external steel belt; the external steel belt is an austenitic stainless steel belt of which the carbon content is less than 0.025 percent; the carbon content of the flux core is not greater than 0.04 percent and carbon accounts for 18.0 to 24.0 percent based on the total weight of the flux-cored wire; the flux core comprises the following components in percentage by weight: 18.5 to 25.0 percent of metal chromium powder, 8.0 to 10.0 percent of metal nickel powder, 2.0 to 5.0 percent of electrolytic manganese metal, 1.0 to 3.0 percent of aluminum magnesium alloy, 28.0 to 35.0 percent of rutile, 3.0 to 5.0 percent of quartz, 2.0 to 5.0 percent of zircon sand, 2.0 to 5.0 percent of feldspar, 1.0 to 2.0 percent of cryolite, 2.0 to 5.0 percent of arc stabilizer and the balance of iron powder; and the arc stabilizer consists of K2O, Na2O and TiO2 in a weight ratio of (6.0-8.0):(8.0-10.0):(68.0-70.0), and the water content is not greater than 400 ppm.

The invention discloses high-permeability sand-burning-preventing paint for casting and a preparation method thereof. The high-permeability sand-burning-preventing paint is prepared from the following raw materials: refractory aggregate, a binding agent, an activating agent, a thickening agent, a suspending agent, a defoaming agent and a carrier, wherein the masses of the binding agent, the activating agent, the thickening agent, the suspending agent, the defoaming agent and the carrier respectively account for 0.5-2.5 percent, 0.01-0.05 percent, 0.1-0.5 percent, 1.5-5.0 percent, 0.01-0.1 percent and 40-220 percent of the mass of the refractory aggregate; the refractory aggregate is a mixture of one or two of zircon powder and chromite fines in any proportion; the binding agent is phenolic resin or a mixture of the phenolic resin and one or more than two of oxidized rosin and ethyl silicate; the activating agent is alkylphenol ethoxylates; the carrier is ethanol; the thickening agent is polyvinyl butyral; the suspending agent is lithium bentonite; and the defoaming agent is normal butanol.

The invention discloses a selective catalyst for removing oxynitrides from tail gases of diesel vehicles and a preparation method thereof. Cordierite honeycomb ceramic serves as a carrier, and the oxides of vanadium, zirconium, tungsten and titanium form a catalytic active site. The preparation method comprises the following steps of: sequentially dissolving vanadium pentoxide, a zircon salt, tungsten trioxide and titanium dioxide into the aqueous solution of oxalic acid, adding a bonder into the mixed solution to prepare pulp, impregnating the cordierite honeycomb ceramic in the pulp, drying the cordierite honeycomb ceramic for 1 to 3 hours at 100 to 150 DEG C, and roasting the cordierite honeycomb ceramic for 2 to 4 hours at 450 to 550 DEG C. In the invention, the preparation method is improved, and a powder catalyst is improved into a honeycomb selective catalytic reduction (SCR) catalyst applied to the removal of the oxynitrides from the tail gases of the diesel vehicles, so the high-efficiency catalytic removal of the oxynitrides can be realized at the temperature of 205 to 515 DEG C; and in the presence of steam or SO2, the activity of the catalyst is kept over 80 percent.

The invention relates to a welding material technology, in particular to a nickel-base welding rod. The welding rod uses a SNi6062 welding wire as a core wire. The electrode coating comprises the following solid ingredients in percentage by mass: 36-50% of rutile, 2-7% of titanium pigment, 20-30% of fluorite, 3-8% of cryolite, 2-4% of phlogopite, 2-4% of zircon sand, 0.5-1.5% of sodium carbonate, 5-10% of manganese metal, 2-4% of ferrotitanium containing 25-35% of Ti, and 2-4% of ferroniobium containing 50-60% of Nb. The nickel-base welding rod has the advantages of favorable performance of production technique, smooth welding rod surface, high yield, stable eccentricity; during welding, the nickel-base welding rod has the advantages of stable electric arc, basically no splash, favorable slag detachability and outstanding operating performance; and the appearance of the welding seam is beautiful, the height of a weld bead is moderate, the wetting angle of a welding seam is moderate, and the strength and plasticity of deposited metals are moderate.

The invention relates to a flux-cored wire for austenitic stainless steel all-position welding, and the flux-cored wire is composed of a flux core and an external stainless steel belt, wherein, the flux core accounts for 22-24wt% of the flux-cored wire, and the flux core comprises the following components in percentage by weight: 20-23% of metal chromium powder, 7-8.5% of metal nickel powder, 2-4% of electrolytic manganese metal, 3-4% of aluminium powder, 0.5-1% of ferrotitanium, 32-34% of rutile, 1-2% of quartz, 2-4% of zircon sand, 4-6% of albite, 2-4% of potassium feldspar, 1-1.5% of cryolite, 1-1.5% of lithium carbonate, 0.1-0.5% of bismuth oxide and the balance of iron powder. The ratio of the albite to the potassium feldspar in the flux core is 1.2-2, the sum of the albite and the potassium feldspar is not more than 10wt% of the flux core, the external stainless steel belt is the austenitic stainless steel 304L, the carbon content is less than 0.025wt%, the diameter of the flux-cored wire is 0.9-1.2mm, and the flux-cored wire can be used for realizing the austenitic stainless steel all-position welding.

The invention discloses a shell making method for a deep blind hole of a precision casting. The method comprises the following steps of: making a wax pattern module; coating the module to make a shell; sequentially coating a surface layer, a transition layer, a third layer and a fourth layer; after coating the third layer or fourth layer, performing air drying until the shell is completely dried; stirring silica sol zircon powder slurry and mullite sand according to a mass ratio of 4:(6-6.5) into paste to obtain filling; pouring the filling into the position of the deep blind hole of the casting; then aligning the deep blind hole of the casting with a fan for forced air drying until the deep blind hole of the casting is completely dried; continuously reinforcing according to the casting size until the required layer number of the shell is obtained; and dewaxing to obtain a corresponding shell. The shell making method for a deep blind hole of a precision casting, disclosed by the invention, is simple and convenient to operate, effectively solves the difficulty in shell making for a shell deep blind hole of a precision casting, enhances the strength of the shell at the deep blind hole, greatly reduces the defects of breakage, deviation and the like of the shell at the deep blind hole, realizes an obvious effect and fundamentally guarantees the delivery time of the products for customers.

A method for preparation of an anode for a solid oxide fuel cell in which a plurality of zircon fibers are mixed with a yttria-stabilized zirconia (YSZ) powder, forming a fiber / powder mixture. The fiber / powder mixture is formed into a porous YSZ layer and calcined. The calcined porous YSZ layer is then impregnated with a metal-containing salt solution. Preferred metals are Cu and Ni.

The invention discloses a manufacturing method of a surface layer shell which is precisely cast by stainless steel and carbon steel, which is characterized by being completed by the following production steps of: (1) preparing a refractory coating; (2) preparing a surface layer shell; and (3) drying the surface layer shell. As mullite sand of 80 to 100 meshes instead of expensive imported zircon sand is adopted in an adhesive layer, the manufacturing method of a surface layer shell which is precisely cast by stainless steel and carbon steel reduces the production cost; as in the preparation of the refractory coating, appropriate wetting agents and anti-foaming agents are added into silicone liquid and zircon powder is used, the performance of the shell is changed and the shell is caused to be good in permeability; as the flow rate of the refractory coating is controlled to be 38 to 45s, the roughness value of a cast piece is low. By testing, performance indexes of cast products of the surface layer shell which are made in the precise casting by the method meet the standard requirements; the surface layer shell is not only high in size precision and low in surface roughness value, but also the production cost can be reduced by 10 to 20 percent.

The invention provides a Zr-Al-Si composite ceramic bead with high wear resistance and high strength and a processing technique thereof. The Zr-Al-Si composite ceramic bead comprises the following components by weight percent: 2-65% of ZrO2, 2-60% of Al2O3, 10-50% of SiO2 and 5% of MgO and mischmetal. The production method comprises the following steps: firstly, evenly mixing zircon sand, zirconia, aluminia, magnesia, kaoline and mischmetal, then carrying out ball milling with a wet method, drying to prepare superfine pulverulent body, rolling and molding, sintering at high temperature, and polishing to obtain the Zr-Al-Si composite ceramic beads with high wear resistance and high strength with the diameter being Phi 0.2mm to Phi 15mm. The prepared ceramic bead has flexibly adjusted density, wide application, wear resistance, stable chemical property and simple process and is easy for scale production.

The invention relates to a centrifugal casting roller coating and a preparation method thereof. The centrifugal casting roller coating is characterized by comprising the following compositions in percentage by mass: 12 to 15 percent of zircon powder, 8 to 10 percent of quartz powder, 8 to 10 percent of bauxite, 0.3 to 0.6 percent of silica sol, 0.1 to 0.4 percent of sodium carboxymethyl cellulose, 0.15 to 0.35 percent of alkyl benzene sodium sulfonate, 0.15 to 0.35 percent of sodium sulfate, 0 to 0.02 percent of n-butyl alcohol, 0 to 0.02 percent of n-octyl alcohol, 0.10 to 0.18 percent of fatty alcohol polyethenoxy ether, and the balance being water, wherein the mass percentage of the zircon powder + the quartz powder + the bauxite is more than or equal to 30 percent and less than or equal to 35 percent, the mass percentage of the alkyl benzene sodium sulfonate + the sodium sulfate is more than or equal to 0.35 percent and less than or equal to 0.55 percent, and the mass percentage of the n-butyl alcohol + the n-octyl alcohol is more than or equal to 0.02 percent and less than or equal to 0.03 percent. The coating is used for centrifugal casting roller production after stirring, grinding and sieving, and has good use effect.

The invention provides a 460MPa-level flux-cored wire for ocean engineering. The 460MPa-level flux-cored wire comprises a carbon steel sheath and a flux core, wherein the carbon steel sheath accounts for 84-87% of the total mass of the flux core; the flux core accounts for 13-16% of the total mass of the flux-cored wire; the flux-cored wire consists of the following components in percentage by mass: 30-42% of rutile, 1-2% of sodium fluoride, 3-6% of feldspar, 3-5% of ferrotitanium, 1-3% of silicon iron, 0.5-1% of rear earth, 3-5% of magnesium powder, 5-10% of electrolytic manganese, 1-2% of aluminum powder, 7-9% of nickel powder, 4-7% of ferroboron, 0.2-0.5% of graphite, 3-6% of silicon-manganese alloy, 0.5-1% of zircon sand and the balance of Fe and inevitable impurities. By virtue of control in aspects of chemical components, diffusible hydrogen, low-temperature stability and the like, the 460MPa-level flux-cored wire meets the requirements of crack resistance and low-temperature impact resistance, is good in all-position welding process, attractive in welding seam and excellent in mechanical property, has seawater corrosion resistance; and content of diffusible hydrogen of deposited metal reaches ultralow hydrogen level.

The invention is a centrifugal casting radiant tube coating and a preparation method thereof, the coating comprises the ingredients (mass percent) of: 25-30% of diatomite of, 5-10% of zircon powder, 1.0-1.2% of titanium powder, 1.5-1.8% of iron powder, 4.5-5.0% of sodium bentonite, 2.0-2.5% of polyvinyl alcohol, 0.8-1.0% of sodium alginate, 3.5-4.0% of silica sol, 0.8-1.0% of sodium dodecylbenzene sulfonate, 0.05-0.08% of silane and 46.82-49.95% of water, wherein, the mass percent of the diatomite and the zircon powder is not less than 35% and not more than 37%, the mass percent of the titanium powder and the iron powder is not less than 2.7% and not more than 2.9%, and the mass percent of the sodium bentonite plus the polyvinyl alcohol plus the sodium alginate is not less than 8.0% and not more than 8.2%. The inventive coating is used for the centrifugal casting radiant tube after dry-blending, mixed grinding and sieving, uniformly distributed bulges (namely pitting surface) can be formed on the outer surface of the radiant tube to improve heat efficiency of the radiant tube. The inventive coating also has excellent adhesive force, high temperature strength and crack resistance, thus reducing defects on the surface of the radiant tube and improving quality of complex tube. Using the inventive coating to cast the radiant tube can result in remarkable economical benefit.