269results about How to "Improve metallurgical quality" patented technology

The invention relates to a method for preparing a TiAl alloy plate by argon atomization in powder metallurgy. The method comprises the following steps of: reducing the content of inclusions in TiAl alloy powders by purity smelting in a cold-wall crucible and high-purity argon atomization; performing hot isostatic pressure compaction on the high-purity prealloy powder which is atomized by pure argon under such conditions that the temperature is 1100 to 1300 DEG C, the pressure is 140 to 200 MPa and the compaction time is 2 to 4 hours; removing coatings of the alloy blank after hot isostatic pressure compaction and then performing surface treatment and coating; heating alloy and rolling at a high temperature; and removing coatings to obtain a powder TiAl alloy plate. The plate has the advantages of uniform deformation, good surface quality, fine and uniform texture, low oxide and impurity contents, small thickness, good overall mechanical property and high quality and reliability. The method solves the key problems in development and application of TiAl alloy powder-metallurgy plates, and provides a technical support for innovation and progress of civil industry and aerospace industry.

The invention discloses a deposition forming manufacturing method of parts and molds, and belongs to the field of non-mold growing manufacturing and remanufacturing. The method comprises the following steps that S1, the three-dimensional CAD model of a workpiece to be formed is subjected to hierarchical slicing; S2, the CNC codes of all hierarchical slices are acquired; S3, deposition forming is conducted layer by layer according to the CNC codes of all the hierarchical slices, the fine portions of the workpiece are formed by laser, and one or more technologies in electric arc welding, electron beam welding, electroslag welding and submerged-arc welding is or are adopted to form the thick wall and the non-fine portions of the workpiece; or in the S3, a heat source which is compounded by laser beams and gas protection electric arcs or a heat source which is compounded by the laser beams and vacuum protection electronic beams is adopted for forming the thin wall and the fine portions of the workpiece, and the gas protection electric arcs or the vacuum protection electron beams are shut down. According to the deposition forming manufacturing method, direct deposition forming can be achieved to obtain parts and molds which are stable in structure property and high in manufacturing precision and are provided with thin walls or fine portions.

The invention discloses a quick isothermal forging method and device for preparing a less-deformable alloy cake blank. The device comprises a heating device, an automatic feeding device, a horizontal hydraulic forging device, a blank positioning device and a flame heating device. A mould material used by the device is a nickel-based alloy with creep strength which is higher than the flow stress of a forged high-temperature alloy under corresponding forging temperature and deformation rate. In the method, a homogenized electroslag remelting continuous directional solidification technology or other processes with maneuverability can be selected for preparing a high-alloyed less-deformable alloy directional solidification billet, as well as a fine grain billet prepared by adopting the processes, such as powder metallurgy and the like. The method and the device have the advantages of short production period, convenience for control and low cost, and are suitable for mass production of large-size high-clean and uniform tissue high-alloying less-deformable alloy cake blanks.

The present invention belongs to the field of material processing technology. The equipment includes one crystallizer, one coil over the crystallizer with DC current passing through, one magnet over the DC coil to introduce the DC magnetic field into the melt in the upper part of the crystallizer, one coil outside the crystallizer with low-frequency current passing through. It has low-frequency electromagnetic field frequency of 15-30 Hz, DC magnetic field strength of 0.01-0.06 T, and AC magnetic field strength in the margin inside the crystallizer of 0.01-0.06 T. The semi-continuous low-frequency aluminium alloy casting process has casting temperature 680-750 deg.c, casting speed 50-150 mm/min and cooling water pressure 0.06-0.12 MPa. The present invention has fined cast ingot structure, isometric crystal grains, low cost internal stress, improved surface quality and hgh ingot quality.

The invention discloses a heat mould steel material in the alloy steel material manufacturing technological domain, which comprises the following parts: 3.5-4.0%Cr, 2.0-2.5% Mo, 1.0-1.5% V,1.0-1.5% W , 0.1-0.5% Mn, 0.1-0.25% Ni, 0.3-0.35% C, 0.1-0.5% Si, 0.005-0.01% S, 0.01-0.02% P and Fe. The preparing method comprises the following steps: (1) fusing; (2) refusing electric slag; (3) evening at high temperature; (4) forging; (5) annealing; (6) forging blank; (7) annealing to obtain the product with hardness between 48-54HRC and impaction flexibility more than 300J.

The invention belongs to the technical field of preparing and processing of titanium and a titanium alloy, and particularly relates to a method for manufacturing titanium and titanium alloy and part thereof by taking hydrogenated sponge titanium as a raw material. The method comprises the following steps: hydrogenating sponge titanium; synchronously ball-milling to prepare hydrogenated titanium powder or mixed powder; pressing the powder; quickly sintering and synchronously dehydrogenizing; thermally mechanically solidifying or forming; performing complete vacuum dehydrogenizing; and obtainingan alloy product. The method realizes synchronously ball-milling to prepare mixed powder from hydrogenated sponge titanium and alloying raw materials, and the powder does not need to screen, so thatthe powder yield is greater than 96%; and under protection of inert atmosphere, pressing, quick heating and alloying, thermal mechanical solidifying and forming are completed. The method is short in process flow, is high in efficiency, can prepare the titanium and the titanium product with high compaction (greater than or equal to 99.8%) and low oxygen content (lower than or equal to 0.26%); mainmechanical properties of the alloy are higher than level of common deformed titanium alloy; and cost is obviously lower than that of conventional powder metallurgical titanium alloy.

The invention relates to an active agent applying to magnesium alloy welding, belonging to the material engineering technical field, which is characterized in that: the active agent is composed of TiO2, Cr2O3, MgO, MnO2, and CaO and the weight proportion is TiO2: 40 to 70%, Cr2O3: 5 to 20%, MgO: 2 to 20%, MnO2: 5 to 20%, CaO: 5 to 20%. Firstly, the active agent is grinded to powder, then is dried and cooled; secondly, the active agent is mixed with acetone or alcohol and then is equally coated or sprayed on the surface of the welding bead; finally, after the acetone or the alcohol is volatilized, welding can be implemented. The active agent has the advantages that: the weld penetration can increase at least twice; the weld joint of magnesium alloy is well moulded; the joint is of high quality and the intensity can be above the 95% of the intensity of the parent metal; the deformation due to welding is reduced; the invention is of easy operation and high productivity.

The invention belongs to the technical field of engine manufacturing, and specifically discloses a manufacturing method for a dual-metal dual-performance titanium alloy integral blade disc, and a wheel disc [1] and a blade part of the integral blade disc are manufactured from different materials. The manufacturing method comprises the following steps of manufacturing titanium alloy blade blank of different materials by adopting an electron beam fused deposition additive manufacturing method on the basis of a wheel disc forged piece; then, performing mechanical processing or electrochemical machining until a designed dimension of a blade; and finally, realizing manufacturing of the dual-metal dual-performance titanium alloy integral blade disc. The manufacturing method has the characteristics of low manufacturing cost, a short period and high metallurgical quality. The blade and the wheel disc [1] are manufactured from different materials, so that mechanical property advantages of the materials can be sufficiently brought into play, the requirements, on high strength and high strain fatigue characteristics of the wheel disc [1], of the integral blade disc, and the requirements, on high stress fatigue and endurance properties, of the blade are met, and therefore, the purpose of reducing weight by enabling the whole blade disc to serve under a high temperature condition or replacing the high-temperature alloy integral blade disc is realized.

The invention discloses a thermo-mechanical treatment process of a great-length Cu-Cr-Zr-Si alloy contact line. The process includes: smelting Cu-Cr-Zr-Si alloy, with Cu accounting for 0.30% to 0.50%, Cr accounting for 0.10% to 0.15% and Zr accounting for 0.01% to 0.02% in content, with a combined protective layer composed of mixed inert gas and a covering dried charcoal protective layer, in an induction furnace; and performing drag casting with a horizontal continuous casting system with electromagnetic stirring and a local heater to obtain rods 16 to 120mm in length. By high-frequency inductive thermal rolling, step heating and water-cooling solidification, cold rolling, split ageing and finish drawing or cold rolling, the alloy contact line having symmetrical grooves in two sides, 110 mm<2> to 150 mm<2> in sectional area and 1800 to 2000 m in singular length. The process has the advantages that metallurgical quality of products is high, and the performances meet the needs of various overhead line systems for modern high-speed railways and low-speed heavy duties.

The invention discloses a preparation method of ultrahigh-strength high-plasticity hot stamping forming steel, and belongs to the technical field of automobile steel. The steel comprises the following chemical components of, in percentage by mass, 0.30%-0.55% of C, 1.0%-2.5% of Si, 1.0%-3.0% of Mn, 0.5%-2.0% of Cr, 0.05%-2.0% of Ni, 0.01%-0.10% of Al, 0.04%-0.15% of Nb, less than or equal to 0.5% of Mo, less than or equal to 0.08% of RE, less than 0.015% of P, less than 0.015% of S, less than or equal to 1.0% of Cu or less than or equal to 0.06% of V, or the combination of the two, and the balance of Fe and inevitable impurity elements, and Si+Mn+Cr is larger than or equal to 3.5% and less than or equal to 5.5%; and automobile parts are obtained through the steps of smelting, pouring solidification, hot rolling, acid pickling, cold rolling, annealing, hot stamping forming and the like. The preparation process of the hot forming steel part is simple, and the structure obtained after hot stamping forming is a martensite matrix and 1.5%-7.0% of retained austenite; and after the components are optimized, it can be guaranteed that the tensile strength of parts is larger than or equal to 2200 MPa, the yield strength is larger than or equal to 1300 MPa, the total elongation is larger than or equal to 9.0%, and the steel is suitable for automobile safety parts and other high-strength-toughness parts and has very important significance on achieving high toughness and light weight of automobiles.

The invention discloses a production technology for casting wear-resistant thin plates by compounding double liquid metals, and aims to replace the conventional build-up welding abrasion-resistant plate production technology with the production technology. The production technology disclosed by the invention comprises the following steps: a gravity casting double casting system is combined with a casting technology; a special chilling material is used for adjusting the temperature fields of molten metals entering a cavity to ensure that the temperature gradient of the part I, in contact with the chilling material, of a first molten metal entering the cavity first is larger, while the temperature gradient of the part II, far away from the chilling material, of the first molten metal is smaller; pouring a second molten metal into the rest space of the cavity after the part I of the first molten metal is in a solid phase and the part II of the first molten metal is in a solid-liquid phase or a liquid phase, so as to ensure that the two molten metals are combined metallurgically but not mixed. Through the adoption of the production technology, under the premise that the metallurgical quality of a metal of a wear layer is superior, the dilution effect of a base material to the alloying constituent of the wear layer is effectively reduced.

A technology for smelting the refractory Fe-base alloy includes such steps as primary smelting in ordinary electric arc furnace by return oxygen blowing method and smelting the qualified refractory Fe-base alloy in AOD furnace. Said second step includes blowing the mixture of argon gas and O2 in ratio of 4:1 for decarbonizing, heating, blowing the mixture of argon gas and O2 in ratio of 1:1 when C content is 0.1%, sampling and analyzing, regulating contents of its components, blowing argon gas when C content is 0.03%, adding prereducing slags, prereducing, sampling and analyzing, adding reducing slags, blowing argon for dissolving slags, blowing argon for 3 min, adding Ti in ladle, tapping, and casting rod electrodes.

The invention belongs to the technical field of preparing of a deformation high-temperature alloy GH4169 disk forge piece for an advanced aero-engine, and relates to a method for reducing the internalresidual stress of a GH4169 alloy large-size disk forge piece. The method includes the following steps of preparing a GH4169 alloy pure smelting cast ingot, conducting uniform heat treatment on the GH4169 cast ingot, cogging the cast ingot, preparing a biscuit, conducting compounding and coating, conducting gradient-speed-control constant-temperature die forging, conducting heat treatment on thedisk forge piece, conducting rough machining and conducting stress relief annealing. By means of the prepared low-stress GH4169 alloy disk forge piece, it is ensured that the internal stress of the deformation high-temperature alloy cast ingot is slowly released, the internal metallurgical quality of the alloy ingot is improved, and the disk forge piece can be used for preparing an advanced aero-engine high-pressure compressor disk, a high-pressure turbine disk, a low-pressure turbine disk and other parts.

The invention discloses a smelting process of nitrogenous high alloy heat-resistant steel ZG3Cr24Ni7N, which includes preparing a steel ladle, primary smelting in an electric arc furnace, refining the steel ladle and blowing nitrogen from the bottom of the ladle. The nitrogen which is rich in sources and low-price is used as material, the nitrogen is blown to molten steel for nitrogen alloying, and accordingly production cost of nitrogenous steel is lowered greatly. Alloy recovery efficiency is improved by reasonable processes, so that the problem that chemical components are difficult to control is solved, and the metallurgical quality of molten steel is improved.

A Ti-Mo-Ni alloy ingot preparation method is characterized in that Ni-Mo intermediate alloy (the mass proportion content of Mo element is 20-35%) is added, the production steps of the Ti-Mo-Ni alloy ingot include that: titanium sponge, Ni-Mo intermediate alloy or Ti-Mo intermediate alloy are mixed uniformly and pressed into electrode blocks, the electrode blocks are welded into consumable electrodes through welding modes such as plasma arc, and the Ti-Mo-Ni alloy ingot is prepared through twice vacuum consumable electric arc smelting. The Ti-Mo-Ni alloy ingot produced by the preparation method has uniform and stable chemical compositions, has the chemical composition deviation of being less than 0.15%, is segregation free and overcomes the defect of high density metallurgical inclusion. The invention is applicable to producing the Ti-Mo-Ni alloy ingot with high metallurgical quality requirement.

A structural frame for a turbomachine, such as an intermediate frame or an exhaust frame, the frame including at least two coaxial rings, an inner ring and an outer ring, together with radial arms interconnecting the rings. At least one of these elements includes a plurality of parts that are fastened together by bolting.

The invention discloses a preparation method of a deformed high-temperature alloy ingot. The method adopts the preparation process of raw material pretreatment, vacuum induction smelting, hot-fittingannealing, electroslag remelting, hot-fitting annealing, vacuum self-consumption and hot-fitting annealing; the cleanliness of a smelting furnace material is improved through the raw material pretreatment; electrodes with uniform components can be obtained through vacuum induction smelting; the impurities can be further reduced by electroslag remelting, so that a cast ingot is compact in structureso as to obtain an electrode ingot with more excellent quality; and vacuum self-consumption remelting further enables an alloy cast-state dendritic crystal tissues to be refined and the tissues to behomogenized so as to realize a good feeding effect, and the metallurgical defects of severe segregation, looseness, shrinkage and the like are avoided. According to the method, hot-fitting annealingafter smelting in each step is carried out, so that cracks of the electrode or the re-molten ingot in the cooling process can be prevented, and finally a high-quality cast ingot with good surface quality, no crack defect, fine cast dendritic structure, low segregation and low stress is obtained, the percent of pass of the cast ingot is improved, and the high-quality cast ingot has remarkable economic benefits.

The invention discloses a steel wire rod for a union melt welding wire with tensile strength of 650 MPa grade for a coating-free weathering steel bridge, and belongs to the field of weathering steel welding materials. The steel wire rod is prepared from chemical composition in percentage by mass: 0.04-0.09% of C, 0.12-0.32% of Si, 1.60-2.20% of Mn, less than or equal to 0.015% of P, less than or equal to 0.005% of S, 0.25-0.55% of Cr, 0.6-1.10% of Ni, 0.20-0.35% of Cu, 0.10-0.40% of Mo, 0.02-0.15% of Ti, 0.010-0.025% of Nb, 0.005-0.030% of Ca, less than or equal to 0.030% of Zr, less than or equal to 0.025% of Ce, less than or equal to 0.0010% of B and the balance of Fe and other unavoidable impurities. Based on the steel wire rod for the union melt welding wire, the invention further provides the union melt welding wire with the tensile strength of 650MPa grade for the coating-free weathering steel bridge. The welding wire and the steel wire rod are suitable for the welding of the coating-free steel bridge with tensile strength of 650 MPa, wherein the tensile strength of deposited metal is greater than or equal to 650 MPa; the yield strength is greater than or equal to 500 MPa; the elongation is greater than or equal to 22%; and the low-temperature impact energy KV2 of the deposited metal at -40 DEG C is greater than or equal to 80 J.

The invention discloses a laser additive manufacturing method for a multihole micro-channel structure. The laser additive manufacturing method for the mulithole micro-channel structure comprises the following steps that a three-dimensional model is established and subjected to layered slicing, and a laser scanning path is acquired; a base material is fixed, and stainless steel/titanium alloy powder is put into a powder cylinder; argon is fed into a forming chamber, and the base material is paved with the powder; laser additive manufacturing equipment is started to conduct scanning machining; aforming cylinder is lowered by a distance of the thickness of a layer, a powder laying device lays a layer of powder on the current machined layer until the structure machining is completed; and a part is subjected to annealing treatment, and the multihole micro-channel structure is obtained. After being formed, the multihole micro-channel structure manufactured through the laser additive manufacturing method is compact, fine and uniform in texture, the metallurgical quality is good, leakage does not occur in the pressing process, the complex inner channel structure is high in size precision,the cross section shape and the distribution limitation of an inner channel are reduced, and the product performance is high; and after the complex multihole inner channel structure is formed, the welding working procedure is not needed, the material utilization rate is increased, working procedures are reduced, and the part manufacturing period is shortened.