973 results about "Vacuum induction furnace" patented technology

The invention relates to high-temperature alloy technology, and in particular provides an isometrical cast nickel-base high-temperature alloy with low density, high incipient melting temperature and good casting property and a preparation process thereof, which can be used for floating tile materials of a combustion chamber. The alloy comprises the following compositions by mass percentage: 0.03 to 0.06 percent of C, 5 to 12 percent of Cr, 5.5 to 6.5 percent of Al, 3 to 8 percent of Co, 3 to 7 percent of W, 2 to 4 percent of Mo, 1.6 to 3.2 percent of Nb, 0.01 to 0.03 percent of B, 0.008 to 0.025 percent of Y and the balance of Ni. A vacuum induction furnace is adopted to smelt a master alloy, and a smelting crucible is a CaO crucible or a MgO crucible; and the operation process comprises the following steps: putting alloying elements such as carbon, chromium, cobalt, tungsten, molybdenum and niobium in proportion and a nickel plate into the crucible; melting the alloy when the vacuum degree reaches between 50 and 0.1 Pa; and after completion of the melting, refining for 30 to 300 seconds at a temperature of between 1,550 and 1,600 DEG C, cutting off electricity, forming a film, breaking the film to add Al and Al-Y and Ni-B interalloy for uniform stirring, and casting a master alloy pig at a temperature of between 1,450 and 1,500 DEG C. The invention solves the problems of low incipient melting temperature, poor plasticity and inoxidability and the like of the nickel-base high-temperature alloy.

The invention relates to a method for smelting a nickel-based high temperature alloy in a vacuum induction furnace. The method sequentially comprises the following steps of: I, putting alloy raw materials into the furnace in a ratio; II, closing a furnace cover, vacuumizing, and performing power transmission to melt furnace burden; III, melting at the speed of less than or equal to 1 / 2 maximum furnace capacity / hour; IV, after the furnace burden is completely melted, starting performing bottom argon blowing, and refining for 20 to 25 minutes; V, stopping argon blowing, adding Al and Ti, and alloying; VI, after Al and Ti are completely melted, performing bottom argon blowing, and refining; VII, after refining is finished, closing a vacuum pump, and filling argon into the furnace and an ingot mold; VIII, alloying at the finishing point, namely adding B, Zr and a rare earth element, and adding a Ni-Mg alloy; and IX, performing electrified tapping after 3 to 4 minutes, and casting into an alloy ingot. By the method for smelting the nickel-based high temperature alloy in the vacuum induction furnace, refining time is 35 to 40 minutes, and the nickel-based high temperature alloy with very low carbon content can be obtained.

The invention relates to a directional-freezing heat-proof corrosion-resistant nickel base cast superalloy with low cost and excellent performance. The cast superalloy has the chemical composition range by weight percentage as follows: C is 0.04 to 0.09; Cr is 14.5 to 15.3; Co is 9.0 to 9.9; W is 4.7 to 5.9; Mo is 1.6 to 2.3; Al is 2.8 to 3.3; Ti is 4.2 to 5.0; Hf is 0.3 to 0.6; Ta is 0.3 to 1.5; B is 0.06 to 0.10; Y (adding quantity) is 0.015; Mn is less than or equals to 0.2; Si is less than or equals to 0.2; P is less than or equals to 0.008; S is less than or equals to 0.008; Fe is less than or equals to 0.5; the other weight percentage is composed of Ni. A vacuum induction furnace is adopted to smelt master alloy, and the directional-freezing is performed in a liquid-metal-cooled (LMC) furnace to prepare columnar grain alloy; the vacuum degree of a directional furnace is less than or equals to 5*10<-4>mmHg, the casting temperature ranges from 1480 to 1570 DEG C, the drawing velocity is 3 to 15mm / min, the temperature gradient is 95 to 145 DEG C / cm, and the temperature of melting tin ranges from 250 to 350 DEG C. The invention provides the heat-proof corrosion-resistant superalloy, which contains Ta, does not contain alloying elements that are Re (with low cost), Nb, Zr and Ce, and has a stable microstructure. Compared with cheC88 Y-BN, the tensile-strength (using Delta (b) and Delta0.2 to represent) is increased more than 30 percent, the plasticity is improved obviously, the lasting temperature is risen by 30 DEG C under the same stress condition, and the cast superalloy is applied to manufacture turbine blades of a combustion turbine which is used under 930 DEG C.

A superpure high-nitrogen stainless austenite steel contains Cr (17-19 wt.%), Mn (12-16 wt.%), Mo (2-3 wt.%), Cu (0.5-1.5 wt.%), Ni (0-0.2 wt.%), N (0.4-0.6 wt.%), C (0-0.05 wt.%), Si (0-0.5 wt.%), S (0-0.009 wt.%), P (0-0.009 wt.%) and Fe (rest). It is smelted by vacuum induction furnace, where nitrogen is added in FeCrN, CrN or MnN mode.

The invention belongs to the technical field of rolled steel, and in particular relates to a manufacturing method of a spray formed high-vanadium high-speed steel composite roller. The high-vanadium high-speed steel comprises the following chemical components in percentage by mass: 1.7 to 1.8 percent of C, 1.2 to 1.6 percent of Si, 5.0 to 6.0 percent of Cr, 1.2 to 1.4 percent of Mo, 0.5 to 0.6 percent of Mn, 8.0 to 10.0 percent of V, and the balance of Fe; and the roller core is made of ball milling cast iron. The invention also discloses a preparation method of the radiation roller. The preparation method comprises the following steps of: preheating the roller core to a certain temperature by using an induction coil, simultaneously smelting the high-speed steel of the outer layer in a vacuum induction furnace, atomizing the high-speed steel molten metal flow by adopting a spray forming method and using nitrogen, and depositing the molten metal on the rotary roller core for compounding. The outer texture of the compound roller is uniform, rough eutectic carbides and texture segregation are eliminated, and good metallurgical combination is formed between the roller core and a spraylayer; and the spray formed compound roller has high hardness on the surface, good abrasion resistance, improved fatigue performance and longer service life, and has higher and better economic benefits as equipment is mature.

A stainless austenite steel for medical implantation contains Cr(17-22 wt.%), Mn (12-20 wt.%), Mo (1-3 wt.%), Cu (0.5-1.5 wt.%), N (0.4-0.7 wt.%), Ni (0-0.02 wt.%), C (0-0.03 wt.%), Si (0-0.75 wt.%), S (0-0.01 wt.%), P (0-0.025 wt.%) and Fe (rest). It is smelted by vacuum induction furnace. Its advantage is very low content of toxic Ni.

The invention discloses nanometer / ultrafine crystal structure ultrahigh-strength plasticity austenitic stainless steel and a preparation method, and belongs to the field of ultrahigh-strength plasticity alloy steel production. Raw materials comprise the following chemical components: 0.08-0.15% of C, 0.35-0.75% of Si, 7.5-10% of Mn, 0.5-0.9% of Cu, 1-1.5% of Ni, 14-16% of Cr, 0.1-0.25% of N, P notmore than 0.06%, S not more than 0.03%, and the balance of iron and inevitable impurities. After smelting by a vacuum induction furnace, a casting blank is forged, and a forging is hot rolled; twicecold rolling annealing is performed after the solid solution treatment; a nanometer / ultrafine crystal composite structure is obtained by using reversion of strain induction martensite and recrystallization of deformation austenite. The ultrahigh-strength plasticity of stainless steel is realized through fine crystal strengthening, back stress reinforcement, deformation induction twins effect and deformation induction martensite effect. The prepared stainless steel is prominent in comprehensive mechanical performance; the yield strength reaches 1150-1320 MPa, and is 3.2-4.5 times in an originalsolid solution state; the tensile strength reaches 1350-1440 MPa; the ductility still achieves a higher level of 39.2-47.3%; the cost is lower; and the preparation method is simple and feasible.

The invention belongs to the field of production of ultrahigh-strength plastic alloy steel, and relates to a preparation method of micro / nano-structure ultrahigh-strength plastic stainless steel containing Nb. The preparation method comprises the steps of: firstly preparing materials according to a composition proportion, adding 0.05-0.15% of Nb element on the basis of 316L austenitic stainless steel, then carrying out vacuum induction furnace smelting, casting blank forging, forged piece hot rolling and solution treatment, carrying out cold deformation on the steel plate which undergoes the solution treatment with deformations of 40%, 60%, 80% and 90% and with single reduction in pass controlled within 3-10% to prepare steel plate with different cold deformations, annealing the steel plate which undergoes the cold deformation with heating rate controlled at 50-200 DEG C / s, with heating temperature within 750-950 DEG C and with heat preservation time within 5-100s, and cooling to the room temperature at a cooling rate of 50-400 DEG C / s to obtain a superfine austenite structure with micro-nano scale. The obdurability of the material is synchronously improved. The yield strength of the final product can be up to 750-800MPa, the strength of extension is up to 1100-1200MPa and the percentage of elongation is 35-45%.

The invention provides a method for largely preparing superfine spherical titanium aluminium-based alloyed powder, which belongs to the technical field of powder preparation. The method comprises the following steps: smelting high-purity aluminium and titanium sponge as main raw materials and Al-Nb intermediate alloy, Ti-B alloy, tungsten powder and high-purity yttrium scraps as auxiliary raw materials into an alloy cast ingot in a vacuum consumable electrode arc skull furnace or a vacuum induction furnace; then carrying out coarse crushing and vortex airflow milling to prepare irregular superfine alloy powder; and finally carrying out plasma spheroidization of radio frequency (RF) and the like to prepare the superfine spherical titanium aluminium-based alloyed powder. The prepared alloy powder has the advantages of high purity, fine particle size, narrow particle size distribution, good uniformity, high sphericity, good flowability and the like and can meet the demands of the technical industrial production of injection forming, gel injection molding forming, thermal spraying and the like.

The invention discloses a process for preparing Cu-Cr-Zr alloys applicable to contact lines. The process comprises the following steps that alloys comprising 0.30 to 0.50 percent of Cu, 0.10 to 0.15 percent of Cr, 0.01 to 0.02 percent of Zr and Si are melt in a vacuum induction furnace, wherein alloy elements, namely Cr, Zr and Si, are added by master alloys; fine casting-state crystal grains and oversaturated matrix tissues having secondary dendritic crystal spaces are obtained by controlling solidification velocity and cooling velocity; rolling in fit, drawing deformation and annealing thermal treatment to the fine casting-state crystal grains and oversaturated matrix tissues are carried out so as to control deformation degrees and parameters for the thermal treatment; and the strain-hardening effect and the precipitation strengthening effect are organically combined. Therefore, the alloys have the advantages of excellent tensile strength, electrical conductivity and high-temperature resistant softening capacity and lower cost under the conditions of simplified process and the simpler apparatus and components, and are applicable to industrial production.

The invention relates to the field of single crystal superalloys, particularly to a high-strength hot-corrosion-resistant Ni-based single crystal superalloy and a preparation method, and is mainly applied to high-temperature components applied to various marine environments and turbine high-temperature components of ground industrial gas turbines. The superalloy comprises chemical components in percentage by weight as follows: 11-15% of Cr, 5-9% of Co, 0.5-2.0% of Mo, 3.0-5.0% of W, 4.5-7.0% of Ta, 3.5-5.6% of Al, 2.3-3.7% of Ti and the balance of Ni. A vacuum induction furnace is used for smelting, a mother alloy is cast firstly, and then the high-strength hot-corrosion-resistant single crystal superalloy is prepared according to a single crystal growth technology and a heat treatment system. The Cr and refractory metallic elements with higher content are selected, but the content of the Ti element is reduced. Meanwhile, the crystal boundary is eliminated through a single crystal technology, so that the hot corrosion resistance, the high-temperature mechanical property and the structure stability of the alloy are further improved.

This invention relates to a magnetic material. The components of material are Fe100-x-yGaxMyQ where x=10-40, M is Al, Be, Cr, In, Cd, Mo, Ge, y=0-15, Q is C, N, O additional doping. Main points of its technique are according to the requirement of the invented material components to smelt the mother alloy in a magnetic suspension over or vacuum induction furnace, to process monocrystal or polycrystal oriented materials with the high-temperature gradient quick directional solidification or czochralski or Bridgeman method under 1000-1200 deg.C for 1-48 hours then cool to 750-600 deg.C in the furnace and keep temp. for 0.2-48 hours, then quenching with water, or cool furnace to room temperature with different cooling speed for 750 to 600 deg.C or apply 500-20000 e magnetic field in the cooling process.

The invention relates to a method for producing a low-activation martensitic steel for a fusion reactor by melting. The method comprises: step one, a charging material is smelted in a vacuum induction furnace: (1) when a vacuum degree is between 0.1 and 10 Pa, argon gas is passed through the vacuum induction furnace till the vacuum degree is between 0.005 and 0.08MPa, and a smelting temperature is between 1450 and 1650 DEG C; (2) alloys are added in sequence: firstly, pure Fe is melted; Cr and W are added into the furnace; then Ta and V are added into the furnace, and finally C and Mn are added into the furnace; simultaneously, the level of an oxygen content in the pure Fe is observed; before Cr is added, a little of C is added into the furnace for carrying out deoxidation treatment; (3) on-line detection is carried out to the compositions of alloy elements; the alloy elements are added according to a detection result; and (4) after the compositions are qualified, a mixture is cast under the vacuum at a casting temperature of between 1450 and 1550 DEG C. Step two, according to the compositions and the inner quality level of a cast ingot which is obtained by vacuum induction and melting, whether the cast ingot is remelted and refined in a vacuum electroslag remelting furnace or a common electroslag remelting furnace with argon protection. Step three, a needed CLAM steel bar material is prepared by the production of forging, cogging and hot rolling. The method has the characteristics of simple smelting operation, stable process and low production cost; the compositions and impurities of the produced CLAM steel meet the design requirement; and the method has no aliquation of the compositions and tissues and high degree of purity and is suitable for the application of the fusion reactor.

The invention provides a preparation process for preventing the formation of surface impure crystals and recrystallization on a mono-crystal hollow turbine blade. According to the preparation process, a spherical wax piece is arranged at an exposed part (tail end) of a positioning platinum wire; a thin wax film is brushed on the other exposed parts; the exposed part is covered with a fireproof material which is the same as a mold shell material in a shell making process; after de-waxing, an end part spherical cavity and a platinum wire face micro-gap are formed; a heat insulation cavity is formed by the cavity and the side micro-gap in a vacuum induction furnace in a mono-crystal preparation process; a heat bridge effect of the exposed platinum wire part is avoided so that an alloy is prevented from partial overcooling and the formation of impure crystal is inhibited; and furthermore, the cavity and the platinum wire side micro-gap provide a releasing space to the deformation of the platinum wire and the partial residual stress is prevented from occurring, and the recrystallization is prevented from occurring in a post heat treatment process of the blade.

The invention discloses a method for preparing low-cost neodymium iron boron (NdFeB) by adding a heavy rare earth oxide into an ingot recasting sheet, which comprises the following steps of: putting didymium, boron, aluminum, copper, niobium, cobalt and iron into a vacuum induction furnace in an ingredient proportion, introducing argon. and refining and casting into a casting sheet; putting the casting sheet into a hydrogen breaking furnace to break the hydrogen; adding 1.04 to 5.05 weight percent of the heavy rare earth oxide in a powder weight ratio; stirring two kinds of powder in a mixer, pulverizing with an airflow grinding machine, and putting the powder into a mold of a molding press; orienting in a magnetic field and performing compression molding; putting blanks into an isostatic pressing machine for pressing, and making into green bodies after maintaining the pressure; and sintering the green bodies in a vacuum sintering furnace at the temperature of between 1,000 and 1,100 DEG C to prepare the NdFeB magnets. The ingot is modified into a casting sheet, so the coercive force of the magnet can be effectively improved. By adding heavy rare earth elements which are better distributed in the crystal boundary and on the grain crystal edge at the pulverizing stage, the capacity of improving the coercive force is far higher than that of directly adding the heavy rare earth elements at the smelting stage; and the formula cost can be reduced by replacing high-price heavy rare earth raw materials by lower-price heavy rare earth oxides.

The invention discloses a manufacturing method of a soft magnet silicon-aluminum alloy magnetic powder core with small amounts of rare earth element cerium or lanthanum, which comprises the following steps: 1) smelting industrial pure iron, polycrystalline silicon, pure aluminum, cerium-iron alloy or lanthanum-iron alloy in a vacuum induction furnace into FeSiAl alloy cast ingots with small amounts of cerium or lanthanum, wherein the alloy cast ingots comprise the components of 9.0-9.8% of Si, 5.4-6.0% of Al, 0.02-0.25% of Ce or La, 0.006-0.015% of C, 0.008-0.010% of O2, 0.008-0.028% of S, 0.03-0.035% of P and balance of Fe; and mechanically crushing into FeSiAl alloy powder, carrying out high-heat treatment in a shielding gas atmosphere, and then screening; 2) carrying out surface passivation treatment on the FeSiAl alloy powder with phosphoric acid and alcohol, then adding 0.20% of kaolin, 0.20% of lubricant and 0.50% of parting compound, uniformly mixing, and carrying out pressure forming; and 3) carrying out heat treatment and surface spraying. The invention can increase the resistivity of the magnetic core and reduce the high-frequency eddy current loss, and has lower magnetic core loss. Besides, the invention improves the temperature stability of the magnetic permeability, and enables the decline of the magnetic permeability to be less than 3% when the working temperature rises to 125 DEG C.

The invention belongs to the technical field of new materials, and relates to a gamma'-phase high-temperature-stability cobalt-base high-temperature alloy with gamma / gamma' two-phase structure, which is a candidate material for high-temperature hot end components of gas turbines for aviation, spaceflight, vessels, power generation and the like. The alloy comprises the following components in atomic percentage: 4-12% of Al, 4-12% of W, 1-4% of Ta, 1-6% of Ti, 0-10% of Cr, 0-3% of Mo, 0-2% of Hf, 0-1% of C, 0-1% of B and the balance of Co. The preparation method comprises the following steps: smelting in a vacuum induction furnace, carrying out solid solution heat treatment at 1250-1300 DEG C, and carrying out aging heat treatment at 1000-1100 DEG C. After carrying out L12-type gamma'-phase high-temperature reinforcement, the gamma' shape is cubic, the volume percent is higher than 60%, and the gamma'-phase is uniformly distributed in the gamma-phase. Compared with the traditional cobalt-base high-temperature alloy, the alloy provided by the invention has higher application temperature; and compared with the recently developed similar cobalt-base alloys, the alloy provided by the invention has higher gamma'-phase solution temperature and gamma / gamma' two-phase structure stable existence temperature.

The invention relates to the field of smelting and specifically relates to a smelting method of ultra-low oxygen pure steel. A vacuum electric furnace or a vacuum induction furnace is adopted for smelting and vacuum pouring, and the vacuum degree is required to be 0.05-100Pa; after a metal charge is molten, a vacuum state is kept, molten metal is boiled for 5-30min, the oxygen content is reduced by vacuum carbon-oxygen reaction, and no deoxidizer or deoxidization alloy is added. The standing is performed for 20-30min after alloying, and the molten metal is boiled for 5-30min in the vacuum state. When the oxygen content is below 10ppm, 0.5-3kg / t of Si-Ca-Al-Mg-RE composite deoxidizer is added, the standing is performed for 1-10min after adding, then vacuum pouring is performed, and then the pure steel with the total oxygen content of below 4ppm can be obtained. The invention aims at solving the problems that existing steel ingots and cast blanks have more internal inclusions with relatively large sizes, the purity is not high and the channel segregation is serious. Simultaneously, by adopting a rare earth composite additive to perform modification treatment on the inclusions in the steel, the sizes of the inclusions are reduced, and the number of the inclusions in the steel is reduced, thus a new effective way is provided for pure smelting of molten steel.

The invention discloses an iron-based nanocrystalline soft magnetic alloy with electromagnetic interference resistance and a preparation method thereof. The general formula of the iron-based nanocrystalline soft magnetic alloy with electromagnetic interference resistance is Fe100-x-y-z-wSixAlYNizMw, wherein M is selected from at least one of Mo, Cu, Cr, Nb, Ti and Zr, x, y, z and w are respectively used as the weight percents of Si, Al, Ni and M, 100-x-y-z-w is the weight percent of Fe, x is not less than 2 and not more than 10, y not less than 2 and not more than 8, z is not less than 1 and not more than 5 and w is not less than 0.5 and not more than 1. Pure metal raw materials are blended according to the general formula and placed in a vacuum induction furnace for smelting to obtain a master alloy; then the master alloy is smelted by an electric arc overflow type rapid quenching furnace and quickly and continuously cast to the surface of a chilling copper roller to obtain thin strips or sheets which are subject to ball milling flattening treatment to obtain flattening powder; and finally mixing and processing the flattening powder and a caking agent into a sheet-shaped flexible material for resisting electromagnetic interference. The invention has controllable process parameters and is suitable for quick and continuous production of industrial scale; and an obtained magnet has extremely-high magnetic conductivity and the magnet shielding effect is improved.

The invention discloses a FeCoCrNiMn-containing high-entropy alloy which is prepared from the following components in percentage by atom: 5-35% of iron, 5-35% of cobalt, 5-35% of chromium, 5-35% of nickel, 5-35% of manganese and 0.01-0.3% of nitrogen. A preparation method of the FeCoCrNiMn-containing high-entropy alloy comprises the following steps: dosing; smelting: smelting with an induction magnetic levitation furnace, a vacuum arc furnace or a vacuum induction furnace, and preparing a CoCrFeMnNiNx high-entropy alloy under argon protection; putting the prepared alloy raw materials into thefurnace, closing the furnace door, vacuumizing, introducing argon and electrifying to start smelting; smelting a sample repeatedly for at least 5 times so as to ensure uniformity of the alloy components; forging the smelted ingot, and performing solution treatment on the forged FeCoCrNiMnNx high-entropy alloy by preserving heat for 6h at 1,100 DEG C; rolling the high-entropy alloy block; preserving heat of the rolled alloy for 6h at 800 DEG C, taking out the alloy and cooling in air. According to the FeCoCrNiMn-containing high-entropy alloy disclosed by the invention, the alloy strength is obviously improved on the premise of keeping high plasticity.

The invention discloses a preparation method for electromagnetic wave interference resistant iron silicon aluminum nickel alloys. The invention comprises the following steps: firstly, ferrum, aluminum, silicon and nickel with a purity more than 99.9 weight percent are taken as raw materials and laid into a medium frequency vacuum induction furnace for smelting, and a master alloy is obtained; secondly, the master alloy after smelting is laid into a quick quenching device; an alloy ingot casting is quickly poured on a water-cooling roll wheel which rotates at high speed after arc remelting under the protection of high purity inert gases, and a quickly condensed sheet band or a quickly condensed sheet is obtained; thirdly, the sheet band or the sheet is laid into a ball mill for ball milling flat processing, and flat powder is obtained; fourthly, the flat powder is laid into a stainless steel tube which is then vacuumized and filled with high purity inert gases for protection, and then the stainless steel tube is laid into a tube furnace for heating, heat preservation and cooling along with the furnace; fifthly, the flat powder and binding agents are mixed and milled for processing the sheet. The preparation method for the electromagnetic wave interference resistant iron silicon aluminum nickel alloys adds adequate nickel into Sendust alloys, thereby the processability of the alloys is improved; the ball milling time is reduced; the cost of industrial production is saved; simultaneously the magnetic conductivity can be improved and the magnetic shielding effect can be improved.

The invention relates to a method for preparing a titanium aluminum intermetallic compound from a hydrogenated titanium-aluminum alloy through a short process. High-purity aluminum and titanium sponge serve as raw materials and are smelted into titanium-aluminum alloy cast ingots in a vacuum consumable electrode electric arc kish furnace or a vacuum induction furnace, the cast ingots are then crushed to be powder in a coarse mode, the powder is subjected to hydrogen treatment to obtain brittle hydrogenated alloy powder, and then the alloy powder is grinded to be microfine titanium-aluminum alloy powder by using vortex air flows; rough bodies are formed by manufacturing the hydrogenated alloy powder and subjected to a dehydrogenation reaction in the sintering and heating process, the alloy powder after the dehydrogenation reaction is high in surface activity and easy to densify through sintering, and the titanium aluminum intermetallic compound product is finally obtained and is high in purity, low in oxygen content and high in relative density. The method is short in technological process, high in operation stability, high in repeatability and capable of achieving mass continuous production; the prepared titanium-aluminum alloy powder has the advantages of being high in purity, low in oxygen content, small in particle size, narrow in size distribution, good in evenness and the like and is suitable for compression molding, injection molding and gelcasting molding.

The invention belongs to the field of metal ceramic material preparation, and provides a method for preparing superfine titanium carbonitride. The method comprises the following steps of: firstly, ball-milling and mixing nano TiO2 with an organic carbon source, and preparing into a piece material in a cold pressing mode; feeding the piece material into a vacuum sensing furnace, vacuumizing till the pressure inside the furnace is less than or equal to 50Pa, increasing the temperature to 300-800 DEG C and preserving the temperature for 0.5-2h; subsequently increasing the temperature to be 1000-1900 DEG C and preserving the temperature for 0.5-2h, wherein vacuumizing is constantly performed in the temperature preservation process; stopping vacuumizing after the temperature preservation is accomplished, introducing nitrogen so as to make the pressure in the furnace be of 1.1-1.2 atmosphere pressures; preserving the temperature for 1-4h to sufficiently nitridize the raw material; and subsequently decreasing the temperature, taking out the piece material, crushing, ball-milling and grading so as to obtain the superfine titanium carbonitride of which the Fisher particle size is less than 1mm. A TiCN powder material prepared by using the method is high in purity, few in impurities, small in particle size, uniform in particle size distribution and spherical in morphology, and can be used as a raw material of a cutting tool, a metal ceramic, a spraying material and the like.

The invention relates to a crucible for vacuum induction melting and a manufacturing method thereof. The crucible is tied on a bottom brick in an induction coil of a vacuum induction furnace. The crucible is characterized by being designed as a double-layered composite structure, wherein the inner layer is an inner shell which is used for melting and made of high-chemically stable crucible material with low decomposing pressure; and the outer layer is an outer shell which is made of low-cost crucible material and has the functions of heat insulation and support. The manufacturing method comprises the following steps in sequence: (1) paving a layer of outer shell material of the crucible at the bottom of the tied crucible, paving a layer of inner shell material of the crucible, and rammingthe material of the crucible; (2) mounting a graphite core, and placing a thin cylinder between the graphite core and an asbestos insulation layer; (3) tying the inner and outer shells of the crucible, and adding the inner shell material of the crucible between the graphite core and the thin cylinder and ramming the inner shell material of the crucible, and then adding the outer shell material ofthe crucible between the graphite core and the asbestos insulation layer; and (4) roasting the induction coil by electrifying the induction coil, and extracting the graphite core after cooling. The crucible manufactured by the manufacturing method of the crucible for vacuum induction melting has low cost.

A preparation method of easy welding high strength toughness X80 pipe line steel for magnesium treatment belongs to the production field of low alloy high strength steel, including first preparing materials according to constituent mixing rate, then smelting in a vacuum induction furnace, forging casting blank and controlling rolling and cooling. The preparation method is characterized in that the heating temperature is 1170-1230 DEG C prior to forging blank residues; the thermal time is 60-120min; and the beginning temperature of coarse rolling is 1100-1180 DEG C; the finishing temperature of coarse rolling is no less than 980 DEG C, the temperature-holding thickness of intermediate blank is 45-50mm; the beginning temperature of finish rolling is no more than 880 DEG C; the finishing temperature of finish rolling is 780-810 DEG C; the pressing rate of finish rolling is more than 3T (T: target thickness of finished products); and the target thickness of finished products is 10-15mm. After finish rolling, the product rapidly enters ACC for cooling control, with the cooling speed being 15-35 DEG C / s. the self-tempering temperature is 400-550 DEG C. The produced high strength toughness X80 pipe line steel has typical acicular ferrite tissue, as well as favorable comprehensive mechanical property and high input energy welding property.

The invention belongs to the field of nickel-based deformed high-temperature alloys, particularly relates to a nickel and cobalt-based high-temperature alloy containing rare earth elements and a preparation method thereof. The nickel and cobalt-based high-temperature alloy is mainly suitable for parts used at high temperature (700-750 DEG C) and under high stress such as turbine disks and blades of aircraft engines. The alloy comprises the following components in percentage by weight: 15-30 percent of Co, 11-17 percent of Cr, 4-6.5 percent of Ti, 1.0-3.0 percent of Al, 0.5-2.5 percent of W, 1-3 percent of Mo, 0-2 percent of Re, less than 0.1 percent of C, less than 0.1 percent of Zr, less than 0.1 percent of B, 0.01-0.5 percent of RE and the rest of Ni. The alloy is smelted with a vacuum induction furnace or a vacuum consuming furnace, is cast into a master alloy with chemical ingredients which are consistent with requirements and is thermally processed. The alloy has excellent processing performance, room temperature to high temperature tensile strength and equivalent durability to a high-performance cast and forged high-temperature alloy TMW.

A crucible for smelting Ti and Ti-alloy in vacuum induction furnace is prepared from boron nitride and flux.

The invention relates to a method for adding a nitrogen element into smelting molten steel of a vacuum induction furnace. The method comprises the following steps of: when a steel grade into which the nitrogen element is needed to be added is smelted in the vacuum induction furnace, adding nitrogen-containing iron alloy which does not damage the quality of molten steel into a hopper; and after the molten steel is subjected to high vacuum refining and deoxidized fully, introducing argon into the furnace and an ingot mold, adding the nitrogen-containing iron alloy for deoxidizing finally, tapping and pouring. The method is simple and reliable; and after furnace charges are molten completely, refined and deoxidized, and the nitrogen-containing iron alloy is added under the protective atmosphere of the argon and is deoxidized finally, the molten steel is tapped and poured, so the aim of adding the nitrogen element accurately at low cost is fulfilled, the content of the nitrogen element can be controlled accurately, and the recovery rate is stabilized to be over 65 percent.

The invention relates to high-strength high dampness and heat sea atmospheric environment resistant weathering resistant steel and a preparing method, and belongs to the technical field of weathering resistant steel. The steel comprises, by weight, 0.01%-0.03% of C, 0.30%-0.50% of Si, 0.60%-0.80% of Mn, 0.90%-1.10% of Cu, 2.80%-3.20% of Ni, 0.20%-0.40% of Mo, 0.25%-0.35% of Sn, 0.05%-0.10% of Sb, not larger than 0.03% of Cr, not larger than 0.02% of Nb, not larger than 0.01% of P, not larger than 0.01% of S, 0.03%-0.05% of RE and the balance Fe. On the basis of a Cu-Ni-Mo alloy system, the Sn, the Sb, the Nb, the RE and other microalloy elements are added, and the Cr content in the weathering resistant steel is greatly reduced. A steel ingot meeting the composition design scope is smelted through a vacuum induction furnace, through the follow-up forging and hot rolling, the weathering resistant steel with the strength of extension larger than or equal to 750 MPa, the yield strength larger than or equal to 650 MPa and the ductility larger than or equal to 15% is finally obtained; the corrosion resistance is reduced by more than 30% compared with a Q450NQR1 traditional weathering resistant steel; and the high-strength high dampness and heat sea atmospheric environment resistant weathering resistant steel is prepared and has the excellent mechanical property.

The invention belongs to the field of nonferrous metal processing, and provides a preparation method for a titanium-nickel memory alloy sheet. The preparation method mainly comprises the steps of smelting, annealing, forging, hot rolling, cold rolling and annealing, acid pickling and inspection; a vacuum induction furnace graphite crucible is adopted for smelting in the smelting step, firstly, a small amount of Ti-Ni mother alloys with the same mass percent as smelting materials is prepared and is placed in the vacuum induction furnace graphite crucible, after power is supplied and smelting iscompleted, a Ti-Ni alloy molten pool is formed, melting the ni alloy molten pool, then crushed materials of sponge titanium and electrolytic nickel are slowly added into the molten pool for smelting,and a titanium-nickel ingot is formed, wherein the chemical components of the titanium-nickel ingot is ensured to comprise 54.5%-55.5% of Ni, less than or equal to 0.04% of C, less than or equal to 0.005% of H, less than or equal to 0.050% of O, less than or equal to 0.04% of N and the balance Ti. According to the method, the problem of poor plasticity of a common titanium-nickel memory alloy sheet at the room temperature is solved, defects of cracking, peeling, folding, oxidizing and impurity pressing are overcome, the mechanical property is improved, meanwhile, the cost is reduced, and theyield during batch production is improved.