1796 results about "Nitriding" patented technology

A semiconductor memory device manufacturing method includes forming a floating gate electrode above a semiconductor substrate, forming an interelectrode insulating film above the floating gate electrode, forming a first radical nitride film on a surface of the interelectrode insulating film by first radical nitriding, and forming a control gate electrode on the first radical nitride film.

This invention relates to an oriented silicon steel and its processing method and equipment. It comprises of 0.035~0.060% of C, 2.5~3.5% of Si, 0.08~1.8% of Mn, 0.005~0.010% of S, 0.015~0.035% of Al, 0.0050~0.0090% of N, 0.01~0.15% of Sn, 0.010~0.030% of P and 0.05~0.12% of Cu, with the rest iron. The processing method includes: a) smelting; b) hot rolling. Billets are heated to 1100~1200 deg.C and rolling temperature is lower than 1200 deg.C with a finishing temperature of above 850 deg.C and a coiling temperature of below 650 deg.C; c) normalizing. Hot-rolled boards are normalizing annealed at 1050~1180 deg.C for 1~20 seconds and 850~950 deg.C for 30~200 seconds and then cooled quickly; d) cold rolling. Boards are rolled to product thickness by one-off cold rolling or repetitious cold rolling with intermediate annealing; e) nitriding, decarbonization and high-temperature and hot-leveling annealing with boards coated with high-temperature annealing isolation agents mainly made of MgO.

The present invention relates to dry refractory compositions having excellent thermal insulation values. The dry refractory composition also has excellent resistance to molten metal and slag. The composition comprises a lightweight filler material selected from the group consisting of perlite, vermiculite, expanded shale, expanded fire clay, expanded silica-alumina hollow spheres, vesicular alumina, sintered porous alumina, alumina spinel Stone insulating aggregate, ettringite insulating aggregate, expanded mullite, cordierite and anorthite, and a matrix material selected from the group consisting of calcined alumina, fused alumina, sintered magnesia, fused magnesia, Silicon fume, fused silica, corundum, boron carbide, titanium diboride, zirconium boride, boron nitride, aluminum nitride, silicon nitride, sialonite, titanium dioxide, barium sulfate, zircon, sillimanite Group of minerals, pyrophyllite, fire clay, carbon and calcium fluoride. The composition may also contain dense refractory aggregates selected from the group consisting of calcined clay, calcined clinker, minerals of the sillimanite group, calcined bauxite, pyrophyllite, silica, zircon, baddeleyite, cordierite , corundum, sintered alumina, fused alumina, fused quartz, sintered mullite, fused mullite, fused zirconia, sintered zirconia mullite, fused zirconia mullite, sintered magnesia, Fused magnesia, sintered spinel and fused spinel refractory clinker. The composition also contains a heat activated binder and a dust suppressant.

There is provided a method for industrially producing a phosphor with high performance, in particular, high brightness. There is also provided a nitrogen-containing alloy and an alloy powder that can be used for the production method. A method for producing a phosphor includes a step of heating a raw material for the phosphor under a nitrogen-containing atmosphere, in which an alloy containing two or more different metal elements constituting the phosphor is used as the whole or part of the raw material for the phosphor, and in the heating step, the heating is performed under conditions such that the temperature change per minute is 50° C. or lower.

It is possible to suppress the rapid progress of a nitridation reaction in heat treatment in producing the phosphor using an alloy for a phosphor precursor as the whole or part of the raw material, thereby industrially producing the phosphor with high performance, in particular, high brightness.

The invention discloses a preparation method of wear-resistant high-chromium cast iron and belongs to the technical field of metal materials. According to the preparation method, common scrap steel, carburant, ferrochromium, ferromolybdenum, copper plates, ferrochromium nitride, ferrosilicon, ferromanganese, ferroboron and aluminum are smelted in an electric furnace so as to form the wear-resistant high-chromium cast iron. The molten wear-resistant high-chromium cast iron comprises the following chemical components in percentage by mass: 3.0-3.5% of C, 18-25% of Cr, 0.3-0.5% of Mn, 0.3-0.5% of Si, 0.18-0.25% of N, 0.5-0.8% of Mo, 0.2-0.4% of B, 0.08-0.12% of Al, 0.5-1.0% of Cu, less than 0.05% of S, less than 0.05% P and the balance of Fe. Molten iron is treated with an inoculator when taken out from the electric furnace, and is treated with a suspending agent when poured, so as to obtain fine solidification structures. Therefore, the wear-resistant high-chromium cast iron has excellent properties.

The invention discloses a method for manufacturing a refractory material by innocent treatment of secondary aluminum ash, and belongs to the field of aluminum industry. The method comprises the following steps: further grinding the secondary aluminum ash until 80% of the secondary aluminum ash passes through a screen with the pore diameter of 74 microns; and calcining the secondary aluminum ash for 0.5-4 hours at the temperature of 1150-1550 DEG C in an oxidizing atmosphere with the oxygen content of 12%-18% to convert metal aluminum, aluminum nitride and aluminum carbide in the secondary aluminum ash into aluminum oxide and volatilize the fluoride salt and chloride salt in the secondary aluminum ash, thereby producing a calcined oxide; cooling the waste flue gas containing fluoride salt and chlorate produced in the calcining process for recovery, and denitrifying and discharging the flue gas. The calcined oxide is independently prepared or mixed with an additive, and the aluminum-magnesium refractory material is prepared after electric arc melting. The preparation method can be used for preparing the refractory material with high purity.

The invention discloses a method for manufacturing a bevel gear of an axle gear box for diesel locomotives, which comprises the steps of blank forging, blank heat-treatment, gear-blank processing, gear-shape processing, gear-end processing, gear-surface heat-treatment, precise reference modification and gear-shape finish-machining, wherein the step of blank heat-treatment comprises the sub-steps of normalizing and thermal refining; the step of gear-blank processing comprises the sub-steps of rough turning and finish turning; the step of gear-shape processing comprises the sub-steps of gear milling, gear hobbing or gear shaping; the step of gear-surface heat-treatment comprises the sub-steps of nitriding, surface quenching and tempering; the step of precise reference modification comprises the sub-steps of end face modification and centre hole modification; and the step of gear-shape finish-machining comprises the sub-steps of gear grinding and polishing. By using the method disclosed by the invention, the production efficiency of the bevel gear can be improved, and the consumption amount and production cost of raw materials can be reduced; and meanwhile, the method is simple in process, and the manufactured bevel gear is long in service life.

The invention discloses an ultra supercritical heat-resistant steel welding rod which is composed of an H08A core wire and coating wrapping the surface of the core wire, wherein contents of sulfur, phosphorus, arsenic, aluminum and the like in the H08A core wire are low, and the coating comprises components of 30%-39% of marbles, 22%-30% of fluorites, 6%-9% of rutiles, 7.5%-8.6% of ferromolybdenum, 29%-31% of chromium metal, 5%-9% of silica powder, 2%-5% of ferrosilicon, 1%-1.8% of ferrovanadium, 0.4%-0.8% of ferroniobium, 1.8%-2.8% of nickel powder, 0.4%-0.8% of sodium carbonate, 0.4%-0.8% of carboxyl methyl cellulose (CMC), 0.2%-0.6% of amorphous graphite, 0.6%-1.5% of nitrogen-bearing ferrochromium, 1.6%-3% of electrolytic manganese, 3%-3.8% of cobalt powder and 4%-5% of ferroboron.

A dispersion hardened FeCrAl-alloy and method of its production which includes in one step, forming a nitride dispersion in a FeCr-alloy, whereby this nitride dispersion includes one or more of the basic elements hafnium, titanium and zirconium, and, in a later step aluminum is added to the nitrided FeCr-alloy. The unfavorable formation of aluminum nitrides has thereby been avoided by adding aluminum after the nitriding. A FeCrAl-alloy with high high temperature strength and high creep strength has thereby been achieved.

A method for increasing the fretting fatigue resistance of an alloy by prehardened a surface of the alloy followed by laser shock peening the prehardened surface. In one exemplary embodiment, an orthopedic prosthesis is formed from a titanium alloy and subjected to surface nitriding followed by laser shock peening. By nitriding the titanium alloy, the hardness of the alloy's surface is increased. Then, by subjecting the nitrided surface of the alloy to laser shock peening, the fretting fatigue of the nitrided surface may be increased by more than 100%.

The invention discloses a gear thermal precision forging machining process adopting carburizing steel 20CrMnTi as a material. The process especially comprises the following steps of: upsetting prolonging, blank manufacturing, die forging, burring, forging aftert-reatment (including quenching, tempering thermal treatment; accomplishing the gear thermal treatment through nitriding, surface quenching and normalizing; and finally carrying out sand blasting to remove a scale cinder and the surface acid treatment), and tooth profile cold-finish. By utilizing the process, the fogging process is simplified, the procedures are reduced; the processed product is good in quality; the production in scale can be realized so as to achieve the purposes of good quality, material conservation, energy conservation and time saving; and meanwhile the service life of a mold can be improved greatly, so that the wear resistance of the manufactured gear is enhanced greatly; the gear point-corrosion spalling is overcome; the strength is improved greatly; the service life is prolonged; and the cost is reduced.

A method for manufacturing an optoelectric device comprising a semiconductor substrate, pads on a surface of the substrate; semiconductor elements, each element being in contact with a pad; and a dielectric region extending in the substrate from the surface and connecting, for each pair of pads, one of the pads in the pair to the other pad in the pair, the method successively comprising the forming of the pads and the forming of the region, wherein the region is formed by nitriding of the substrate, the method comprising the successive steps of: depositing a layer on the substrate; forming portions on the layer; etching the parts of the layer which are not covered with the portions to form the pads; removing the portions; and nitriding the pads and the parts of the substrate which are not covered with the pads, wherein the nitriding step successively comprises: a first step of nitriding of the pads at a first temperature; and a second step of nitriding of the parts of the substrate which are not covered with the pads at a second temperature different from the first temperature.

The present invention relates to a metal surface salt bath nitride nitriding heat treatment method which belongs to the metal part surface heat treatment technology field. The method is performed in the following technical process: first, loading and clamping: the metal part is hung and arranged in a charging basket; second, nitriding: the metal part hung and arranged in the charging basket is positioned in a nitriding furnace, heated and charged with nitriding salt for salt bath and nitriding, and heat is preserved for 30-80 minutes in the condition that the temperature is 540-570 DEG C; third, cleaning: the nitrided metal part is cleaned, and the water temperature is controlled at 60-80 DEG C; the nitriding salt in the nitriding working process comprises carbamide, potassium chloride or barium chloride, sodium carbonate, and K ₂ S, etc., according to the weight percentage, the composition of each component is respectively: 30-40 percent of carbamide, 20-28 percent of potassium chloride or barium chloride, 38-44 percent of sodium carbonate, and 0.0001-0.1 percent of K ₂ S, and the sum of the weight percentage of each component is 100 percent. The present invention has the advantages of smaller deformability, short time, high efficiency, and wide application range; and also can achieve the effect of reducing the cost obviously.

The invention belongs to the field of metallurgy and relates to 48MnV nitrogenous steel and a nitrogen adding process thereof. The 48MnV nitrogenous steel comprises the following components: 0.45-0.51% of C, 0.17-0.37% of Si, 1.00-1.20% of Mn, 0.06-0.11% of V, 0.000-0.025% of Ti, 0.05-0.25% of Cr, 0.00-0.06% of Mo, 0.00-0.06% of Ni, 0.00-0.20% of Cu, 0.0080-0.0150% of N, at most 0.035% of P, at most 0.035% of S, at most 0.020% of O, 0.087-0.097% of Ceq and the balance of Fe and impurities; and the nitrogen adding process is carried out while the N content is controlled to be 0.0080-0.0150%, preferably 0.0090-0.0120%, wherein the target value is 0.0110%, and a manganese nitride iron wire is fed into the steel according to the calculated quantity in one step after a vacuum process is completed. By changing the pre-vacuum nitrogen adding and alloying into the post-vacuum nitrogen adding and alloying, the invention changes the technological process of pre-vacuum nitrogen alloying and post-vacuum slight nitrogen regulation in the metallurgy field, thereby enabling the 48MnV nitrogenous steel to obtain good comprehensive mechanical properties, and improving the strength and toughness.

The invention discloses a nitriding process for H13 die steel. The nitriding process for the H13 die steel comprises the following steps of quenching and tempering the H13 die steel, and then performing hardness screening; cleaning and polishing the surface of the H13 die steel; putting the H13 die steel in a vacuum type gas nitriding furnace, vacuumizing, then introducing nitrogen to recover pressure, and keeping positive pressure; heating at an intensive carburizing stage and a diffusing stage, and insulating for a period of time; cooling to complete nitriding treatment. According to the nitriding process for the H13 die steel, harmful structures are effectively controlled when the H13 die steel is nitridized, so that the service life of a die is greatly prolonged, thereby reducing the cost and the rejection rate.

The invention relates to an electrocatalyst, in particular to a gold-palladium alloy/carbon nitride composite nanomaterial and a preparing method and application thereof. The preparing method comprises the steps that g-C3N4 powder is weighted and dissolved in purified water, and ultrasonic dispersion is carried out; an HAucl4 solution and an H2Pdcl4 solution are added into the mixture in sequence, magnetic stirring is carried out until the mixture is mixed evenly, and an NaBH4 solution is added in a dropwise mode, magnetic stirring is carried out until the mixture becomes uniform; an oil bath reaction is carried out; after the reaction is finished, the mixture is cooled to the indoor temperature; the gold-palladium alloy/carbon nitride composite nanomaterial is obtained after washing, centrifugal separating and drying are carried out. The composite nanomaterial can be used for electrochemical detection for hydrogen peroxide.