213results about How to "Eliminate segregation" patented technology

The invention relates to an inoculant for the manufacture of cast iron with lamellar, compacted or spheroidal graphite. The inoculant comprises between 40 and 80% by weight of silicon, between 0.5 and 10% by weight of calcium and/or strontium and/or barium, between 0 and 10% by weight of cerium and/or lanthanum, between 0 and 5% by weight of magnesium, less than 5% by weight of aluminium, between 0 and 10% by weight of manganese and/or titanium and/or zirconium, between 0.5 and 10% by weight of oxygen in the form of one or more metal oxides, the balance being iron, said inoculant further comprising between 0,1 and 10% by weight of sulphur in the form of one or more metal sulphides. The invention further relates to a method for the production of the inoculant.

The invention discloses a preparation method of a high-voltage lithium cobalt oxide cathode material which comprises the steps: (1) mixing cobaltosic oxide containing doped element M, a lithium source, oxide containing doped element M', a grain refiner and a fluxing agent to obtain a primary mixture; (2) sintering and smashing the primary mixture to obtain primary sintered powder; (3) mixing the primary sintered powder with a coating material to obtain a secondary mixture; (4) sintering and smashing the secondary mixture to obtain the lithium cobalt oxide cathode material. According to the preparation method disclosed by the invention, the problem of microscale segregation of distribution of doped elements in the product is solved by two modes of doped element premixing and dry-method mixing; a coulter type mixing technology is utilized to solve the problem of segregation of different matters in material mixing; the grain refiner and the fluxing agent are combined for use to synthesizea material in a mixed morphology; technologies such as dual effects of doped element surface crystallization catalysis and the coating material and the like are utilized; thus, performance of the high-voltage lithium cobalt oxide is obviously improved.

The invention discloses a method for manufacturing an aluminum alloy hollow section for a sedan bumper, relates to a method for manufacturing an aluminum alloy hollow section, and aims to solve the problem that domestic limousine bumpers are low in tensile strength and non-proportional extension strength and dependent on import. The method comprises the following steps of: 1, preparing alloy melt; 2, casting an alloy cast rod; 3, cutting the cast rod off; 4, turning the cast rod to remove oxide; 5, performing homogenizing annealing; 6, heating a cast ingot; 7, extruding; 8, pre-straightening;9, quenching; 10, straightening; 11, aging; and 12, cutting according to length to obtain the aluminum alloy hollow section for an automobile bumper. The straightness and size of the hollow section prepared by the method completely meet the standards of imported bumpers, and the hollow section has high comprehensive mechanical properties. The method can be used for processing and manufacturing sections for limousine bumpers.

The present invention relates to preparation process of serial lignosulfonate air entraining and water reducing admixtures for concrete. The preparation process includes the following steps: dissolving solid lignosulfonate in water of the same weight, adding catalyst and oxidant, heating after reaction, adding amine and partial aldehyde to aminate, and dropping the rest aldehyde for condensation reaction to obtain the product; adding surfactant and polymer through stirring, and cooling to obtain liquid phase lignosulfonate as air entraining and water reducing admixture. The present invention is used as the admixture for concrete, and has relatively high water reducing rate, capacity of raising the strength of concrete, and certain setting retarding effect to delay the appearance of cement setting heat peak and reduce crack caused by temperature change.

The invention discloses high-chrome corrosion-resisting high-strength pipeline steel and a manufacturing method thereof. The high-chrome corrosion-resisting high-strength pipeline steel is prepared from, by weight percent, 0.04%-0.08% of carbon, 0.15%-0.55% of silicon, 0.15%-0.95% of manganese, 0.030% of phosphorus or less, 0.006% of sulfur or less, 0.8%-2.0% of chrome, 0.15%-0.55% of copper, 0.020%-0.090% of niobium, 0.008%-0.035% of titanium, 0.010% of nitrogen or less and the balance iron and inevitable impurities. The high-chrome corrosion-resisting high-strength pipeline steel is different from universal low-carbon high-manganese composition design, a low-carbon, low-manganese and high-chrome alloying composition system is adopted, the manganese alloy element segregation problem caused by a high-manganese system is eliminated from compositions, and band segregation structure forming is avoided. During molten steel smelting, the refining means of KR molten iron pretreatment deep desulfuration, LF and RH refining and the like are adopted, a dual slag stopping method dephosphorization technology is adopted, a rolling control and cold control rolling process is adopted for controlling phase change temperature, the grain structure is refined, and toughness matching of the pipeline steel is guaranteed; and the produced pipeline steel has excellent corrosion resistance and higher strength and toughness.

The invention discloses an oxidation-resistant alloying grey cast iron and a preparation method of the oxidation-resistant alloying grey cast iron. The cast iron comprises the following components by mass percentage: 3.0-3.2% of C, 1.8-2.0% of Si, 0.50-0.70% of Mn, 0.10-0.50% of Cr, 0.20-0.30% of Ni, 0.03-0.50% of Mo, 0.5-3.0% of Al, 0.05-0.08% of Sr, 0.005-0.15% of Zn, and the balance of Fe and inevitable impurities. The preparation method comprises the steps of melting raw materials, culturing and processing, and pouring, wherein the tapping is carried out at 1450 to 1550 DEG C after melting; the molten iron is processed by being flushed in a ladle and cultured and processed along with the flow, and then slagged and casted. According to the oxidation-resistant alloying grey cast iron provided by the invention, the organization of the grey alloying cast iron material is structured by distributing 6-8 grades of D type graphite with little graphite of A type on a ferrite substrate, so that higher toughness, high heat conductivity and high-temperature oxidization resistance can be achieved, and good casting technical performance can be ensured as well; and the oxidation-resistant alloying grey cast iron can be applied to manufacturing a glass die and a light alloy metal type casting die which can bear the heat impacting of high-temperature formed liquid and cold-heat alternating stress for a long time.

The invention discloses a microalloying method for improving toughness of molybdenum and molybdenum alloy fusion welding lines. The microalloying method comprises the following steps: 1) the surfaces of areas to be welded on workpieces to be welded are pretreated, wherein the workpieces to be welded adopt materials of molybdenum or molybdenum alloys; 2) titanium layers are filled in the joined places of the workpieces to be welded; 3) the workpieces to be welded are placed in an inert gas protective atmosphere or a vacuum environment; and welding areas of the workpieces to be welded are preheated; and 4) the workpieces to be welded are welded; and welding line areas of the welded workpieces are insulated, and are cooled to reach the room temperature to finish microalloying of fusion welding lines of the workpieces. The method can eliminate the segregation problem of impurity elements in the grain boundary, and prominently improves the toughness of the molybdenum alloy fusion welding lines.

The invention provides a steel wear-resistant copper alloy composite sheet, and a preparation device and a preparation method thereof. The preparation device of the steel wear-resistant copper alloy composite sheet comprises a surface processing unit, a shielding gas induction preheating unit, an induction melting unit and a semisolid rolling compound unit which are arranged in turn. The surface processing unit, the shielding gas induction preheating unit and the semisolid rolling compound unit are provided with rectangular channels for lower steel plates to penetrate, and the size of the rectangular channels in the surface processing unit and the shielding gas induction preheating unit is consistent with the section size of the steel plate to be processed. The invention also provides a preparation method of the steel wear-resistant copper alloy composite sheet, and the steel wear-resistant copper alloy composite sheet prepared with the method. The preparation method provided by the invention has the characteristics of continuous production, high finished steel rate, less defects, etc., and is a technological method for producing high-quality composite sheets efficiently.

The invention discloses a method for improving hot-working performance of Mn18Cr18N steel and belongs to the technical field of metallurgy. The method specifically includes the steps that firstly, materials are matched, wherein after electroslag remelting pre-melted slag and rare earth oxide are evenly mixed according to the mass ratio of (2-5):1, drying is performed; secondly, in the electroslag remelting preparation stage, nitrogen is introduced, and raw materials are weighed; thirdly, electroslag remelting is performed; fourthly, in the stage that electroslag remelting ends, the rare earth oxide in electroslag remelting rare earth slag is reduced into rare earth elementary substances through a reduction agent and enters molten steel through the diffusion effect, rare earth reacts with sulfur in steel so that rare earth sulfide can be generated, the content of the sulfur element in the steel is reduced, segregation of the sulfur element in the steel can be eliminated, the hot shortness of the steel is relieved, fine sphere shapes are formed due to the morphology of doping of the rare earth sulfide and doping of rare earth oxygen sulfide, and the mechanical property of the Mn18Cr18N steel can be improved.

The invention discloses 3004 aluminum foil and a preparing method and application thereof. The aluminum foil comprises chemical elements: by mass, 0.15-0.25% of Si, smaller than or equal to 0.55% of Fe, 0.14-0.2% of Cu, 1.02-1.15% of Mn, 0.95-1.1% of Mg, smaller than or equal to 0.05% of Cr, smaller than or equal to 0.15% of Zn, 0.015-0.025% of Ti, smaller than 0.1% of other chemical elements andthe balance Al. The 3004 aluminum foil is obtained by performing 3004 aluminum alloy smelting, refining, standing, online degassing and deslagging, casting, face-milling, uniform heating treatment, hot rolling, cold rolling, intermediate annealing, cold foil rolling and finished product annealing. With the combination of the various elements and the preparing process, the prepared aluminum foil has high strength and toughness, the thickness is greatly reduced when the aluminum foil is used as a container, use is convenient, and the consumption of the raw materials is reduced; and waste ring-pull cans can be adopted as a raw material, the consumption of the raw material is reduced, resources are reutilized, the source of the raw materials for preparing the aluminum foil is widened, meanwhile the burdens on the environment are avoided, the production cost is reduced, and the 3004 aluminum foil has quite good social economic benefits.

The invention provides a heat treatment method of a GH 4780 alloy forging, and relates to the technical field of alloy manufacturing. The method comprises the following step: carrying out solution heat treatment on the GH 4780 alloy forging, wherein the temperature of the solution heat treatment is 1020-1170 DEG C. The GH 4780 alloy forging subjected to heat treatment not only can effectively eliminate the segregation of alloy elements such as Ti, Al and Cr in the smelting process and eliminate metallurgical defects such as cavities, but also can break columnar crystals and promote dynamic recrystallization, thereby refining the crystal grains and improving the strength and plasticity of the alloy forging.

A GH4700 alloy ingot homogenizing treatment method is characterized in that cast-condition alloy is placed into a resistance heated furnace with the temperature lower than 400 DEG C, the temperature is raised to 1130-1150 DEG C at the speed of 100 DEG C/hour, the temperature of 1130-1150 DEG C is kept for 8-10 hours, then the temperature is raised to 1180-1210 DEG C in half an hour, the temperature of 1180-1210 DEG C is kept for 24-32 hours, then the temperature is lowered to 1000 DEG C in a furnace, and the cast-condition alloy is moved out of the furnace to be cooled to room temperature in air. According to the method, Nb and Ti elements of the alloy are made to undergo segregation, the alloy is made to undergo Laves phase elimination, and hot-working plasticity of the alloy is improved.

The invention provides a method for producing hot work mold steel adopting continuous casting billet direct forging. The method specifically comprises the steps that end face seal welding or overlaying is performed on a sawed and cut continuous casting billet, after that, first-time homogenization is performed, and the homogenization is performed for 3-6 h with the temperature being 1150-1320 DEGC; the surface of the continuous casting billet after the first-time homogenization is quenched to 1050 DEG C or below to perform one-way large press down ratio deformation, and second-time homogenization is performed for 10-20 h with the temperature being 1150-1320 DEG C; three-way forging is performed on the steel billet after the second-time homogenization; the initial forging temperature of the three-way forging is 1250 DEG C or below, and the final forging temperature is 800-950 DEG C; and a product is obtained through grain refining and annealing. According to the method for producing the hot work mold steel adopting the continuous casting billet direct forging, by means of organic combination of continuous casting billet special treatment, the two times of homogenization and two times of the forging, kinetic conditions favorable to diffusion of carbon and alloy elements are created, and continuous casting billet central continuity loose pores and other defects, decomposition liquid chromatography carbides and banded structures generated by dendritic segregation are completely eliminated.

The invention discloses a super-strength aluminum alloy drill rod pipe body for a super-deep well and a manufacturing method for the super-strength aluminum alloy drill rod pipe body. The super-strength aluminum alloy drill rod pipe body comprises the following components in percentage by weight: 2.1 to 3.0 percent of Cu, 2.8 to 3.1 percent of Mg, 10.0 to 12.9 percent of Zn, 0.1 to 0.3 percent of Mn, 0.1 to 0.5 percent of Ni, 0.1 to 0.5 percent of Cr, 0.05 to 0.20 percent of Ti, 0.2 to 0.5 percent of Zr, 0.001 to 0.01 percent of B, 0.02 to 0.05 percent of Yb and the balance of Al and inevitable impurities. According to the super-strength aluminum alloy drill rod pipe body and the manufacturing method, heat treatment processes of multistage homogenization treatment, multistage solid solution treatment, aging and the like are adopted, segregation, heterogeneousness and the like in a substrate are greatly eliminated, and the melting-back of an un-melted eutectic phase in the aluminum alloy substrate is remarkably promoted, so that high strength is maintained, hot strength is improved, and the problems of insufficient strength, low surface hardness, insufficient hot strength and the like of the conventional aluminum alloy drill rod pipe body are solved.

The invention discloses a thermo-magnetic coupling field cooperated selective laser-melting device and a heating method thereof. The thermo-magnetic coupling field cooperated selective laser-melting device is characterized in that a magnetic field generator is introduced on the basis of conventional laser selective sintering and heating; during normal printing, a control system controls the magnetic field generator to generate stable static magnetic fields; the static magnetic fields provide lorentz force to change flow field distribution, in a workpiece printing process, of a molten pool; when a workpiece is printed and accumulated to certain thickness, the magnetic field generator is controlled to generate alternating magnetic fields for heating, tempering and thermally treating the workpiece, and then naturally cooling the workpiece to the room temperature; and workpiece printing is continued according to the method until workpiece printing is ended. In a printing process, an unevenworkpiece effect generated by the Marangoni effect can be reduced, various defects caused by the printing process further can be eliminated, crystalline grains are refined, segregation is eliminated,and internal stress is reduced, so that the structure and the performance of the workpiece are more uniform, and therefore, growth of a metallographic structure of a printing material is promoted, and hardness and strength of the workpiece are improved.

The invention provides an aluminum alloy and a casting method thereof. According to the aluminum alloy and the casting method thereof, pure silicon is added into molten aluminum, an aluminum alloy silicon ingot is acquired, and the manufactured silicon ingot serves as an intermediate alloy to be added into the molten aluminum so that an aluminum alloy cast ingot can be acquired. According to the aluminum alloy and the casting method thereof, purification treatment of the pure silicon and a homogenizing working procedure are added, the content of impurities in the molten aluminum is reduced, moreover, due to the fact that the aluminum alloy silicon ingot is the intermediate alloy, the melting point is low, during component adjusting, Si elements are scattered more uniformly, segregation ofthe Si elements is greatly eliminated, and the acquired cast ingot is more uniform in component.

The invention relates to a preparation method for a high-strength and high-plasticity magnesium-zinc-manganese-yttrium alloy and belongs to the technical field of production of a magnesium alloy of nonferrous metal. The preparation method specifically comprises the following steps that (1) smelting is conducted, specifically, a magnesium ingot and a magnesium-manganese master alloy are smelted together, a zinc ingot and a magnesium-yttrium master alloy are added, and after 20-30 min, argon is introduced for 10-20 min, finally, an alloy melt is subjected to deslagging and stood till impurities settle, and semicontinuous casting is conducted to prepare a semicontinuous cast ingot; and (2) extrusion treatment is conducted, specifically, the prepared semicontinuous cast ingot is subjected to homogenization treatment, then cooled to 25-30 DEG C and subjected to sheet turning, and finally, the cast ingot subjected to sheet turning is subjected to extrusion forming according to the extrusion ratio of 16:30 at 400-450 DEG C to prepare the magnesium-zinc-manganese-yttrium alloy. By adoption of the preparation method, the mechanical performance and the plasticity of the alloy can be simultaneously improved, and the use range of the magnesium alloy is effectively enlarged, and the magnesium alloy can replace some zirconium-containing and rare-earth-containing magnesium alloy materials and can be applied to aerospace, military and industrial fields and the like.