415 results about "Titanium aluminum alloy" patented technology

The invention relates to a method for precisely casting a titanium alloy and a titanium aluminum alloy with low cost, which relates to a method for precisely casting the titanium alloy and the titanium aluminum alloy, and solves the technical problem that cast pieces have low surface quality and internal quality in the conventional method for lowering the cost of precisely casting the titanium alloy and the titanium aluminum alloy by using electrically-fused alumina and silica sol. The method comprises the following steps of: preparing a surface layer binder from zirconium sol, silica sol, a wetting agent JFC, n-octyl alcohol, polyvinyl alcohol and latex; adding calcium carbonate, alumina, titanium dioxide and zirconia to prepare a surface layer coating; preparing a shell surface layer; preparing a shell back layer by a universal method for precisely casting the titanium alloy; dewaxing and sintering to obtain a shell; and casting the titanium alloy or the titanium aluminum alloy by using the shell so as to obtain a titanium alloy cast piece or a titanium aluminum alloy cast piece. Compared with a precise casting method by purely using a zirconium-based binder and a zirconia fireproof material, the method has the advantage that raw material cost is lowered by 30 to 70 percent and the method can be used for civil titanium alloy cast pieces and titanium aluminum alloy cast pieces for common aviation.

The invention discloses a friction welding method of a titanium-aluminum alloy turbine and a 42CrMo quenched and tempered steel shaft, which aims to solve the technical problem that when the titanium-aluminum alloy turbine rotor and the quenched and tempered steel shaft are connected by the current method, the tensile strength of a joint is low. The invention has the technical scheme that an embedded groove in a shape of a solid of revolution is processed at one side of the titanium-aluminum alloy turbine; in the welding process, the welding end surface of the turbine shaft has friction with the welding surface of the embedded groove of the titanium-aluminum alloy turbine; and by controlling the friction shortening amount, the casting fins formed at the turbine shaft side are fully filled into the embedded groove. Thus dual effects of metallurgical bonding and mechanical connection of the welding surface are achieved, and the tensile strength of the joint of connecting pieces at room temperature is increased from 390MPa in the background art to 480-537MPa.

The invention belongs to the technical field of non-ferrous metal analysis and particularly relates to an electropolishing preparation method of a sample for EBSD (Electron Back-Scattered Diffraction) analysis of a titanium-aluminum alloy. The electropolishing preparation method comprises the following steps: firstly, carrying out earlier stage treatment on the sample: determining the size of the sample to be smaller than 7mm*6mm*4mm, and carrying out standard metallographic treatment and mechanical polishing on the testing surface; secondly, setting up a portable device: connecting the sample with a positive pole of a power supply, connecting a stainless steel plate with a negative pole of the power supply and matching the bottom end of electrolyte with a magnetic stirrer; thirdly, preparing the electrolyte: selecting 4 to 12 percent of perchloric acid, 55 to 65 percent of methyl alcohol and the balance of n-butyl alcohol according to the volume ratio, wherein the total amount of the electrolyte is 700ml; putting the electrolyte into a beaker with the volume of 1L; fourthly, carrying out electrolysis treatment, washing and drying: controlling the temperature to be 30 DEG C below zero to 20 DEG C below zero, controlling the voltage to be 25 to 35V and controlling the polishing time to be 40 to 55 seconds. The electropolishing preparation method disclosed by the invention has the advantages of large surface area for treating the sample and suitability for preparing titanium-aluminum alloy samples with various components and various test purposes, which are prepared by different processing method. In addition, the electropolishing preparation method has the advantages of easiness and flexibility in operation, no restriction from site facilities and the like, good polishing effect and high rate of finished products; the device has the characteristics of high mobility, low cost, easiness in promotion and wide application prospect.

The invention discloses a rapid thermal pressed sintering molding process for titanium-aluminum alloy targets. A rapid thermal pressed powder molding process is adopted to sinter and mold materials under the combined action of heat and force, and the characteristic that aluminum in the Ti-Al mixture has a low melting point is utilized to bond titanium powder together so as to obtain needed titanium-aluminum alloy targets with various components; and accordingly, titanium-aluminum alloy targets with various components in various dimensions can be prepared, have high compactness, small grains and even components and can satisfy the requirements of large-scale industrialization. The rapid thermal pressed sintering molding process for the titanium-aluminum alloy targets has the advantages of short flows, low cost, hardly oxidated powder, high compactness, good filming effect, even components and large dimensions.

The invention discloses a method for connecting a titanium-aluminum alloy turbine with a 42CrMo steel shaft. The turbine members consist of a titanium-aluminum alloy turbine, an intermediate transitional shaft and a 42CrMo steel shaft, wherein the titanium-aluminum alloy turbine and the intermediate transitional shaft, the intermediate transitional shaft and the 42CrMo steel shaft are respectively combined in a friction welding mode. A friction welding contact part is designed into a mode that a lug boss and a concave groove are combined with each other, the axial cross sections of the lug boss and the concave groove are isosceles trapezoids, an included angle between a base and a hypotenuse of each trapezoid is 30-60 DEG, the length ratio of a top edge to the base of the trapezoid is 0.3-0.7, and the ratio of the flat area formed by the top edge of the trapezoid to the cross sectional area of the shaft is 0.01-0.1. According to the method disclosed by the invention, the bonding strength of the whole structure is effectively improved through increasing the effective contact area of the welding surface; after welded, all materials are ruptured in a titanium-aluminum parent material region; the turbocharging efficiency can be greatly increased; the engine transient responsiveness is enhanced; and the pollutant discharge is reduced; in addition, the method has a simple process and can be used for realizing mass production.

Disclosed is a preparation method of a porous ceramic shell of cast titanium and titanium aluminum alloys, relating to the melt mould precise casting field. The invention solves the problem that cracks are caused when the thin-walled titanium and the titanium aluminum alloys castings are solidified and shrunk due to the large residual intensity of the present shell of cast titanium and titanium aluminum alloys. The method is as following: firstly, wax mould pressing; secondly, coating and hanging four surface layers, and the manufacturing processes of each layer are that coating and hanging coatings of the surface layer, sprinkling zirconic sand, drying in the room temperature, and then the next layer is coated and hung; thirdly, coating and hanging two transitional layers, whose differences from coating and hanging the surface layers lie in that each coated and hung transitional layer comprises a high polymer and a back coating of water latex, and bauxite sand of 50 to 70 orders is sprinkled; fourthly, coating and hanging four to eight reinforcing layers, whose differences from hanging and coating the transitional layers lie in that the bauxite sand of 30 to 40 orders is sprinkled; fifthly, coating and hanging the coatings of an outer layer , which will be dried in the room temperature; sixthly, dewaxing by high pressure steam; seventhly, roasting the shell. The invention can be widely applied in the manufacturing of the shell of titanium and titanium aluminum alloys castings for the national defense and domestic use.

The invention relates to a precise forming method for titanium-aluminum intermetallic compounds. According to the method, yttrium oxide powdery sand is selected as a surface-layer refractory to prepare a ceramic shell for investment casting, and in combination with processes such as a vacuum consumable skull furnace or a vacuum induction water-cooling copper crucible furnace and centrifugal casting, a titanium-aluminum intermetallic compound casting is prepared. The ceramic shell prepared according to the forming method is high in inertia, and good in matching between strength and deformability and collapsibility, and is suitable for investment casting of the titanium-aluminum intermetallic compounds; a prepared casting is complete in forming, the smallest wall thickness can reach 1mm, the dimension precision reaches lower than CT7, a surface pollution layer is thin, surface roughness is less than or equal to 6.3 micrometers, and more importantly, cracks cannot be formed, and therefore, the problems that titanium-aluminum alloy is low in room-temperature plasticity and easy to crack during forming are solved. The forming method is applicable to development and engineering production of various structural parts of the titanium-aluminum intermetallic compounds.

The invention provides a continuous suspension type directional solidification casting device of a cold crucible. Heat-resisting lightweight titanium-aluminum alloy vanes are badly needed in transportation and energy industries, and a traditional directional solidification device causes severe impurity pollution and damages plasticity and toughness of the vanes. The directional solidification casting device aims at improving the efficiency of the directional solidification device of the cold crucible and overcomes the shortcoming that the existing casting device cannot be used for casting vanes with complex shape. A trapezoid boss is annularly arranged on the inner wall of the water cooling copper crucible, an induction coil is wound around the outer portion of the crucible, the boss is placed in the coil, an excited alternating current magnetic field is diffused inwards through crucible gaps to generate a hot area to achieve suspension rod liquid feeding of material rods. The device further comprises a drawing-pulling rod in a crystallizer, a mould casing with cross section being vane-shaped is fixed on the upper end face of the drawing-pulling rod, and the mould casing is heated by an outer induction graphite sleeve. The continuous suspension type directional solidification casting device achieves suspension melting liquid feeding, sequential filling and directional solidification of metal liquid, avoids chemical reaction of a titanium-aluminum alloy melt body and the mould casing and improves directional solidification processing efficiency of titanium-aluminum alloy.

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 relates to a processing method for controlling processing deformation of a titanium-aluminum alloy thin-wall case. The technical scheme of the processing method is as follows: the processing method comprises the steps as follows: a primary rough turning process, a primary heat treatment process, a secondary rough turning process, a secondary heat treatment process, a fine turning process, a third heat treatment process and a finish turning process. According to the processing method for controlling the processing deformation of the titanium-aluminum alloy thin-wall case, reasonable processing parameters are set, and an appropriate cutter is used, so that the processing deformation of the titanium-aluminum alloy thin-wall case is controlled, and the processing requirement is met.

The invention relates to a Gamma-based titanium-aluminum alloy material with high temperature oxidation resistance and a manufacturing method thereof, which aims at overcoming shortages of Gamma titanium-aluminum alloy produced by the conventional technique such as casting, forging and vacuum sintering, etc. The components of the Gamma-based titanium-aluminum alloy material are: 39.8-49.8 percent of Ti (at), 45-48 percent of Al (at), 0.2-0.3 percent of Si (at) and 5-12 percent of Nb (at). To produce the Gamma-based titanium-aluminum alloy material with high temperature oxidation resistance, the mechanical alloying is adopted, namely, mixed powder comprising nano-crystals, amorphous materials and part of TiAl intermetallic compound are fist obtained by high energy ball milling, and then spark plasma sintering is done to the ball-milled mixed powder so as to obtain the Gamma-based titanium-aluminum alloy with high performance in a short sintering time. The Gamma-based titanium-aluminum alloy material prepared by the invention has the advantages of fine TiAl based alloy structure, uniform compositions, high density and excellent high temperature oxidation resistance.

The invention discloses a quick manufacturing method of a titanium-aluminum alloy composite part. The method comprises the following steps of 1. establishing a three-dimensional solid model of the titanium-aluminum alloy composite part by three-dimensional modeling software, dividing the model into thin layers by layering software, obtaining a STL (stereo lithography) format file, and importing the STL format file into quick forming software of an electronic beam quick forming machine; 2. loading titanium-aluminum alloy powder into a power delivery box of the electronic beam quick forming machine, paving the titanium-aluminum alloy powder on a power paving table by a certain powder paving thickness, inputting scanning parameters, scanning and sintering the titanium-aluminum alloy powder in a layer-by-layer way under the vacuum condition, and obtaining the titanium-aluminum alloy composite part after sintering. The method has the advantages that the utilization rate of material is high, the excessive powder can be repetitively used, the cost is saved, the manufactured titanium-aluminum alloy composite part has fine fully lamellar tissues with an average crystalline cluster size of 30mum to 50mum, and the lamellar structures at the lamellar crystalline cluster interface of the titanium-aluminum alloy composite part are staggered.

The invention provides a non-vacuum solar spectrum selective absorption film and a preparation method thereof. The absorption film comprises a stainless steel or copper substrate which is successivelyprovided with a titanium-aluminum film, a titanium-aluminum-nitrogen film, a titanium-aluminum-oxygen-nitrogen film and a titanium-aluminum-oxygen film from inside to outside, wherein the films are prepared by adopting multi-arc ion plating; a target material adopts titanium-aluminum alloy target of which the atomic ratio of titanium to aluminum is 50:50; and the content of nitrogen and/or oxygenin the films is controlled by controlling the flow of argon, nitrogen and oxygen in the atmosphere of multi-arc ion plating. The method comprises: (1) selecting and cleaning a substrate material; (2)baking the substrate material in a vacuum sputtering chamber of a multi-target compound coating machine; (3) performing argon-ion bombardment on the surface of the substrate material; (4) coating thesubstrate material; and (5) performing annealing treatment. The absorption film has the advantages of high absorptivity alpha in a solar spectral range (0.3 to 2.5 microns), low emissivity epsilon inan infrared region (2 to 50 microns) and the characteristic of resisting high-temperature oxidation, thereby meeting the requirements of solar high-temperature utilization.

The invention discloses a preparation method of a chromium nitride titanium aluminum nitrogen gradient hard reaction film. The preparation method sequentially comprises the steps of: firstly, deposition technology and determination of target elements; secondly, selection and pretreatment of workpieces; thirdly, determination of pre-bombardment technique; fourthly, determination of the deposition technique; fifthly, processing of vacuum heating; and sixthly, rotation of workpieces. In the invention, according to the method of preparing a multi-arc ion plated CrTiAlN nitrogen gradient hard reaction film by adopting a combination target of a chromium target and titanium aluminum alloy target, the CrTiAlN nitrogen gradient hard reaction film can be obtained; in addition, the nitrogen content of the CrTiAlN nitrogen gradient hard reaction film are distributed in gradient, the adhesive force is strong (not less than 150 N), and the hardness is high (not less than HV4200). The preparation method reduces the film coating cost, guarantees the synchronous realization of the high film layer hardness and adhesive force, reduces the internal stress of the film and has excellent stability and repeatability.

The invention provides brazing filler metal for brazing titanium alloy and steel or titanium aluminum alloy as well as steel. The brazing filler metal is characterized by comprising the following components in parts by weight: 0-40 parts of Ti, 24-50 parts of Cu, 6-23 parts of Ni, 5-20 parts of V and 9-35 parts of Zr. The brazing filler metal has a good wetting effect for both titanium alloy or titanium aluminum alloy base metal and steel base metal; large quantities of inter-brittle metal compounds can be prevented from being generated to a certain degree; and a high-strength brazing connector can be obtained by using the brazing filler metal.

Heat-resistant lightweight titanium alloy blades are needed urgently in aerospace ship power systems, however a traditional directional solidification device can cause serious impurity pollution, and plasticity index of the blades are damaged. For giving play to efficient pollution-free characteristics of an existing cold crucible directional solidification device and overcoming the defect that blades in complicated shapes cannot be solidified directionally, the invention provides a titanium aluminum alloy blade blank continuous cold crucible directional solidification casting device. An upper induction coil used for stimulating an alternating magnetic field is wound on the outer portion of a continuous water-cooling copper crucible, and hot areas are generated through diffusion towards the inner portion of the continuous water-cooling copper crucible through seams. The titanium aluminum alloy blade blank continuous cold crucible directional solidification casting device further comprises a lower drawing rod arranged in a crystallizer, a mold casing with cross section in the shape of a titanium aluminum alloy blade blank is fixed on the upper end face of the lower drawing rod, and the mold casing is heated by an external induction graphite sleeve. The titanium aluminum alloy blade blank continuous cold crucible directional solidification casting device achieves continuous melting, continuous filling and continuous solidification of titanium aluminum alloy, can greatly shorten contact time of high-activity alloy melt and the mold casing, and prevents the titanium alloy blades from being polluted by the mold casing.

The present invention is direct titanium alloy producing process with titanium containing mineral and belongs to the field of metal titanium smelting technology. The production process includes: arc furnace melting titanium-containing mineral with added reductant to obtain high titanium slag; setting the high titanium slag, rutile or titanium white into plasma high temperature furnace and introducing argon as plasma gas source and electrolytic aluminum to reduce titania to obtain Ti-Al alloy mother liquid, adding slagging agent with the calcium fluoride to adsorb produced alumina to obtain solid crude Ti-Al alloy; making the crude Ti-Al alloy with deoxidant into consumable electrode and electroslag remelting in a vacuum electric furnace to obtain Ti-Al alloy product with oxygen content of 0.05-0.15 wt%. Compared with traditional process, the process of the present invention has short production period, low production cost, less environmental pollution and other advantages.

The invention provides a suspension type cold crucible continuous melting and casting and directional solidification device. Heat-resisting light titanium-aluminum alloy with high strength and high tenacity is especially required in the aerospace shipping industry. However, problems that a supplied alloy liquid is low in degree of superheat and the directional control of solidification structure is difficult exist in prior vertical through type cold crucible directional solidification devices. According to the suspension type cold crucible continuous melting and casting and directional solidification device, a trapezoid boss is annularly arranged on the inner wall of a water-cooling copper crucible, an inductance coil is winded on the outside of the cold crucible, the trapezoid boss is placed in an induction zone of the coil, a master batch rod is melted on the upper portion of the boss, and a billet with a directional solidification structure is prepared on the lower portion of the boss. The suspension force in an axis direction of the crucible during metal melting can be increased by the aid of the boss, the contact of metal melt with cold crucible wall can be effectively avoided, the lateral heat dissipation effect of crucible cold wall can be reduced, and the degree of superheat of the alloy liquid and the directionality of the prepared billet solidification structure are improved.

The present invention discloses a titanium aluminum alloy surface high temperature oxidation and hot corrosion resistant Al-Cr coating; an Al-rich deposition layer, an Al-Cr alloy layer and a Cr diffusion layer are successively arranged from surface to a titanium aluminum alloy substrate. The content of Al in the Al-rich deposition layer remains the same. The content of Al in the Al-Cr alloy layer gradually reduces outside-to-inside to 70%-100% of the content of Al in the titanium aluminum alloy substrate, and the rest in the Al-Cr alloy layer is Cr. The contents of Cr and Al in the Cr diffusion layer respectively gradually reduces outside-to-inside to same as the contents of Cr and Al in the titanium aluminum alloy substrate, and the rest in the Cr diffusion layer is other elements in the titanium aluminum alloy substrate, and the contents of other elements in the Cr diffusion layer respectively gradually rise to same as the contents of the other elements in the titanium aluminum alloy substrate from zero. The invention also discloses a preparation method of the titanium aluminum alloy surface high temperature oxidation and hot corrosion resistant Al-Cr coating; the titanium aluminum alloy surface high temperature oxidation and hot corrosion resistant Al-Cr coating can give titanium aluminum alloy excellent oxidation resistance and heat resistance corrosion performance under high temperature and long term service conditions, and due to the presence of the diffusion layer of the gradient components, the reliable binding strength and excellent thermal shock resistance can be realized.

The invention relates to a production method of a titanium-aluminum alloy target. The method includes the steps of firstly, adding titanium powder and aluminum powder into a V-shaped mixer for mixing; secondly, placing the powder in an isostatic cool pressing capsule, vacuumizing in prior to sealing, pressing for 10-20 minutes, and placing in a vacuum self-propagating high-temperature synthesis furnace for self-propagating reaction to obtain foamed titanium-aluminum alloy; thirdly, crushing the alloy into 200-mesh powder, placing in an isostatic cool pressing capsule, and pressing to obtain titanium-aluminum alloy billets; fourthly, placing the alloy billets in a steel capsule, and vacuum degassing in prior to hot isostatic pressing sintering to obtain titanium-aluminum alloy ingots; and fifthly machining to obtain the finished titanium-aluminum alloy target. Due to the fact that the method adopts the second step for alloying after well mixing of raw materials and before hot isostatic pressing sintering and conditions of each step are strictly controlled, the prepared titanium-aluminum alloy target is high in density and even in crystallite size distribution.

The invention discloses a commercial manufacturing method for directly producing iron and titanium aluminum alloy from iron ore concentrate, and comprises the following procedures: first, carrying out pellet preparation to the iron ore concentrate extracted from the vanadium-titanium magnetite rock and mineral; then, drying the pellets, reducing and fractional melting, and screening and extracting the block iron; last, adopting an aluminothermic reducing method to vanadium-titanium bearing slag so as to obtain vanadium-titanium aluminum alloy. The content of the block iron obtained in the method is about 95 percent; the recycling rates of iron, vanadium and titanium are 90 percent, 85 percent and 85 percent respectively. The commercial manufacturing method has the advantages of high iron, vanadium and titanium integrated recycling and utilization rate, high production rate and no pollution to environment, thus being easy for industrialization promotion and having obvious social and economical efficiency.

The invention discloses a direct control method for a titanium-aluminum-niobium alloy lamellar structure, and belongs to the technical field of control research of high-temperature alloy structures. The method is a control method for a titanium-aluminum alloy structure based on a full peritectic transformation process. By applying a directional solidification technology, the alloy is controlled to be subjected to full peritectic reaction by changing solidification conditions (temperature gradient G and drawing speed V), so that primary beta phase dendritic crystals are fully dissolved in a solidification process, and adverse effects which may be probably caused by the beta phase to the alloy structure are eliminated; and thus, the aim of controlling the direction of the lamellar structure is fulfilled. The method can be realized only in a normal Bridgman directional solidification system, so that the defects of complex preparation process and non-uniform components and performance in a seed crystal method are overcome; the method is a new method for directly controlling the orientation of titanium-aluminum-niobium alloy directionally solidified lamellas through a non-seed crystal method, and has great significance to improving the performance of the titanium-aluminum alloy; and the industrial application of the directionally solidified titanium-aluminum alloy is promoted.