713results about How to "Reduce inclusions" patented technology

This invention concerns a method for stimulating barrier integrity in a subject by administering to a subject a composition comprising docosapentaenoic acid (22:5 n3; DPA). Also the invention concerns a composition comprising DPA and eicosapentaenoic acid (EPA).

The present invention is a method suitable for heat treatment, or a heat treatment method for growing single crystal silicon carbide by a liquid phase epitaxial method, wherein a monocrystal silicon carbide substrate as a seed crystal and a polycrystal silicon carbide substrate are piled up, placed inside a closed container, and subjected to high-temperature heat treatment, by which very thin metallic silicon melt layer is interposed between the monocrystal silicon carbide substrate and the polycrystal silicon carbide substrate during heat treatment, and single crystal silicon carbide is liquid-phase epitaxially grown on the monocrystal silicon carbide substrate. The closed container is in advance heated to a temperature exceeding approximately 800° C. in an preheating chamber kept at a pressure of approximately 10⁻⁵ Pa or lower, the closed container is reduced in pressure to approximately 10⁻⁵ Pa or lower, and the container is transported and placed in the heat chamber, which is in advance heated to a prescribed temperature in a range from approximately 1400° C. to 2300° C., in a vacuum at a pressure of approximately 10⁻² Pa or lower or in an inert gas atmosphere at a prescribed reduced pressure, by which the monocrystal silicon carbide substrate and the polycrystal silicon carbide substrate are heated in a short time to a prescribed temperature in a range from approximately 1400° C. to 2300° C. to produce single crystal silicon carbide which is free of fine grain boundaries and approximately 1/cm² or lower in density of micropipe defects on the surface. Further, the present invention is heat treatment equipment used in carrying out the heat treatment method.

The invention discloses a manufacturing method of low-cost and high-purity medium-carbon bearing steel used for automobile hubs; the manufacturing method comprises the following steps: (a) the mass percentage of the components of the bearing steel is as follows: C: 0.55 percent to 0.58 percent, Si: 0.15 percent to 0.35 percent, Mn: 0.80 percent to 0.85 percent, P: less than or equal to 0.030 percent, S: less than or equal to 0.015 percent, Cr: 0.10 percent to 0.20 percent, Ni: less than or equal to 0.25 percent, Cu: less than or equal to 0.20 percent, Mo: less than or equal to 0.08 percent, Al: 0.008 percent to 0.015 percent, Ti: less than or equal to 30ppm, O: less than or equal to 15ppm, and the rest are Fe and inevitable impurities; (b) smelting, electric furnace initial melting+ ladle furnace refined melting+ vacuum degassing; (c) continuous casting into steel billet; (d) rolling. Compared with the prior art, the technological process has obviously shorter process and lower production cost; the impact resistance, torsion resistance, wear resistance and fatigue endurance of the produced automobile hub bearing are good.

The invention belongs to the field of casting technologies and new materials and particularly relates to a high-strength high-tenacity cast-state QT700-10 and a production method thereof. Compared with ductile iron produced in the prior art, the high-strength high-tenacity cast-state QT700-10 has high strength and a high elongation rate, heat treatment is not needed, heavy metal, such as, Ni and Mo are not added in production, the tensile strength Rm in the cast state is larger than or equal to 700 MPa, the elongation rate A is larger than or equal to 10%, compared with the standard brand QT 450-10, the lowest tensile strength is improved by 55% under the same elongation rate; and compared with the standard brand QT 700-2, the lowest elongation rate is improved by four times under the same tensile strength. The high-strength high-tenacity cast-state QT700-10 can meet requirements of automobile ductile iron castings with high requirements for safety and comprehensive mechanical properties.

Proposed is a Cu—Mn alloy sputtering target, wherein the Mn content is 0.05 to 20 wt %, the total amount of Be, B, Mg, Al, Si, Ca, Ba, La, and Ce is 500 wtppm or less, and the remainder is Cu and unavoidable impurities. Specifically, provided are a copper alloy wiring for semiconductor application, a sputtering target for forming this wiring, and a manufacturing method of a copper alloy wiring for semiconductor application. The copper alloy wiring itself for semiconductor application is equipped with a self-diffusion suppression function for effectively preventing the contamination around the wiring caused by the diffusion of active Cu, improving electromigration (EM) resistance, corrosion resistance and the like, enabling and facilitating the arbitrary formation of a barrier layer, and simplifying the deposition process of the copper alloy wiring for semiconductor application.

The invention relates to a powder preparation process, especially for preparing a nano composite powder, which belongs to the field of powder metallurgical technique. The preparation process is characterized by: weighing the different metal salts in proportion for preparing a salt solution and a mixed salt solution; adding a few acid or alkali for controlling the pH value in a range of less than 4 or more than 10, adding 0.1% to 5% of surfactant, spray drying at the temperature of between 300 C. and 350 C. for preparing the nano oxide composite powder or composite salt powder precursor; obtaining the nano tungsten base composite powder by first reduction at 400 C. to 600 C. and second reduction at 650 C. to 1000 C. . The nano tungsten base composite powder prepared by the process has superfine granularity, uniform distribution, high purity, and good sintering activity.

The invention relates to a plasma atomization method and apparatus for preparing spherical pure titanium or titanium alloy powder, and belongs to the technical field of preparation of titanium or titanium alloy powder. The plasma atomization method for preparing pure titanium or titanium alloy powder comprises the following steps of (1) preparing a titanium wire or titanium alloy wire with the diameter ranging from 3 millimeters to 20 millimeters, (2) using a plasma torch to fuse and atomize the titanium wire or titanium alloy wire in an atomization bin with an argon atmosphere to obtain atomized pure titanium particles or titanium alloy particles, and (3) feeding argon flow with the temperature ranging from 300 DEG C to 500 DEG C into the atomization bin, carrying out laminar cooling on the atomized pure titanium particles or titanium alloy particles to obtain pure titanium or titanium alloy powder. The obtained powder is good in degree of sphericity and low in the content of satellite balls, and has the advantages of being uniform in size distribution, high in purity and degree of sphericity, good in liquidity, low in oxygen content and impurity content, free of bond or cluster phenomenon and the like. The prepared titanium powder can be widely applied to the forming manners such as metal additive manufacturing, powder injection moulding and hot isostatic pressing for manufacturing parts with high precision.

The invention discloses hot work die steel capable of being used for a long term at the working condition of 600-700 DEG C and belongs to the field of material and preparation. The hot work die steelcomprises the following components in percentage by mass: 0.12-0.30 of C, equal to or less than 0.5 of Si, equal to or less than 0.5 of Mn, 1.0-3.0 of Cr, 1.5-2.5 of Mo, 0.3-1.2 of W, 0.5-1.6 of Ni, 0.2-1.0 of V, 0.03-0.15% of Nb, equal to or less than 0.05 of N, equal to or less than 0.03 of S, equal to or less than 0.03 of P, equal to or less than 3.5 of (Mo+W), equal to or less than 1.0 of (Nb+V) and the balance of Fe and unavoidable impurity elements. According to the hot work die steel, low carbon is adopted to form lath martensite so as to obtain high tenacity at room temperature and lowtemperature; through alloying of Cr, W, Mo, V, Nb and the like and the thermal deformation optimization and thermal treatment technology, solution strengthening is improved and MC and M2C type carbide still keeping stability at 600-700 DEG C is formed so as to obtain high temperature strength and thermal stability of the material. Compared with the commonly used hot work die steel at present including H13, 25Cr3Mo3NiNbZr and the like, the high temperature strength at 700 DEG C of the hot work die steel is improved by 50-100%, the tempering thermal stability is improved by 50-100%, the problemabout hot work die steel used at 600-700 DEG C is better solved, and the hot work die steel has longer service life at 600 DEG C and below.

The invention relates to the field of powder metallurgy technology characterized in that, forming the powder with 200 MPa-500 MPa and feeding into sintering furnace, elevating the temperature to 400-700 deg. C. at the speed of 5-20 deg. C per minutes, heat preserving for 15-120 mins, elevating the temperature to sintering temperature of 1150-1350 deg. C. at the speed of 20-60 deg. C per minutes, heat preserving for 30-120 mins.

The invention discloses a method for manufacturing a bimetallic metallurgical composite wear-resisting tube blank, which comprises the following steps: firstly, spraying a water-based zircon powder coating onto a metal tube die after being baked to between 200 and 300 DEG C, wherein the spraying thickness is 1.0 to 3.0mm; secondly, centrifugally casting external liquid metal on the metal tube die after being baked to between 200 and 350 DEG C, cooling the metal tube die after casting, beginning to cast internal liquid metal into the metal tube die when an internal surface temperature of the outer layer is cooled to a temperature lower than a solidus temperature of the external metal; and finally, pouring the internal liquid metal into the metal tube die for centrifugal casting, cooling the metal tube die after casting, and stopping cooling when the outer layer and the inner layer are completely solidified, then the outer layer and the inner layer are metallurgically fused completely, wherein the outer layer is made of a plain carbon steel material or a low-alloy high-strength steel material and the inner layer is made of a high-chromium white cast iron material. The invention also discloses the bimetallic metallurgical composite wear-resisting tube blank manufactured by the method. The outer-layer metal and the inner-layer metal of the tube blank manufactured by the method can be metallurgically fused completely; the qualification rate is improved; and the use safety is high.

The invention discloses a preparation method of a semisolid slurry of a rare earth magnesium alloy. According to the guiding principle of promoting grain nucleation and inhibiting grain growth, pure aluminium is added into rare earth magnesium alloy melt, and a lot of fine dispersed Al2RE intermetallic compound particles which are generated by an in-situ reaction provide nuclei of heterogeneous nucleation for primary alpha-Mg so as to promote grain nucleation; and after the melt is transferred to a tundish, considering stability of a solid-liquid interface during the solidification process, the growth of a primary phase is delayed by reasonable control of cooling conditions in different stages of solidification so as to realize the effect of inhibiting grain growth. The invention provides a low-cost agitation-free green semisolid slurry preparation method. In comparison with a traditional semisolid slurry preparation technology, efficiency of the preparation method is improved greatly and cost is reduced remarkably. By the preparation method, a high-quality rheological slurry is provided for follow-up rheoforming of rare earth magnesium alloy, such as rheo-die casting, rheological squeeze casting and the like. The preparation method has a wide application prospect in rheoforming of a magnesium alloy.

Steel plates for automobile axle housings, the percentage by weight is C0.1~0.18%, Si≤0.5%, Mn1.2~1.6%, Ti0.01-0.06%, Nb0.01-0.04%, P:≤0.025%, S: ≤0.015% and the rest are Fe and impurities. The steel plate production method: casting molten steel smelted in a converter that meets the chemical composition requirements into a slab, according to the percentages of Ti, Fe and Nb, adding TiFe after LF refining treatment to create white slag, and adding NbFe in the converter process or LF refining; Put the slab into the furnace to heat and keep it warm; the starting temperature of rough rolling is 1080-1120°C, the starting temperature of finish rolling is 910-950°C, the temperature of finishing rolling is 830-870°C, three times of continuous rolling after finishing rolling, rolling The reduction rate of the last three passes is not less than 11%, 8%, and 6%; the shear temperature is 150-300°C. In order to improve the mechanical performance index and cold forming performance of the steel plate.

The invention discloses a production method of ultralow-oxygen titanium-containing ferrite stainless steel, which comprises the following steps: 1) preparing molten ferrite stainless steel under a vacuum condition in a vacuum oxygen blowing decarburization furnace, wherein the carbon mass percentage content and nitrogen mass percentage content in the molten ferrite stainless steel are both less than 0.01 percent; 2) performing deoxidization, namely adding 6 to 12 kilograms of aluminum block or grains into each ton of steel and adding 10 to 28 kilograms of active lime into each ton of steel; 3) alloying silicon and aluminum, namely adding 2 to 9 kilograms of silicoferrite which contains 70 to 80 percent of silicon into each ton of steel and adding 0 to 1 kilogram of aluminum blocks or grains into each ton of steel, wherein the aluminum content is 0.02 to 0.1 percent; 4) performing desulphurization; (5) breaking vacuum; 6) softly stirring; 7) feeding titanium wires; 8) feeding silicon and calcium wires, wherein the calcium content is 5 to 30ppm; 9) softly stirring; and 10) continuously casting. The method can be used for producing ultralow-oxygen titanium-containing ferrite stainless steel, prevent or inhibit forming magnesia alumina spinel which are harmful impurities in a production process, improve product quality, prevent the water gap of tundish from being blocked in a continuous casting process and guarantee smooth production.

The frequency of replacement of an insulating spacer disposed between grids of an ion beam irradiation apparatus is to be reduced. In addition, the intervals of the multiple grids in the ion beam irradiation apparatus are to be kept constant. To achieve these objects, in a so-called insulating spacer provided for maintaining insulation between the grids, a groove portion having a bottom onto which sputtered materials are hard to adhere is provided on the central portion of the side surface of the insulating spacer all along its circumference.

The invention belongs to the technical field of corrosion and prevention, and in particular relates to a casting method of an aluminum alloy sacrificial anode. The casting method comprises the following steps: adding basic electrolytic molten aluminum to a resistance furnace; then adding a zinc ingot to obtain molten aluminum alloy; performing jet refining on the molten aluminum alloy by adopting an argon located refining agent; charging argon to refined aluminum alloy melt to degas; drossing oxidizing scum on the surface of the aluminum alloy melt through a drossing tool; adding a low melting point metallic element to drossed aluminum alloy melt; electromagnetically agitating the melt after pressing the low melting point metal; carrying out ceramic filtering; pouring and casting the aluminum alloy melt to a preheated iron anode mould at an even casting speed under the temperature of 700 to 740 DEG C until the mould is full of the aluminum alloy melt; and moving the aluminum alloy melt out of the mould after cooling, solidifying and molding, so as to obtain the aluminum alloy sacrificial anode. The casting method has the characteristics of being short in smelting time, small in loss of iron scale, high in degassing and purifying performances, and low in smelting cost.

The invention provides ladle furnace low alkalinity slag refining process. According to the process, bottom blowing of argon to ladles is carried out in the whole course of steel making and tapping, and ferrosilicon, silicon-calcium-barium and high carbon ferromanganese are sequentially added into the ladles for deoxidation and alloying; under the condition that argon flow is 30 to 50 NL/min, argon is blown to the liquid steel for two to three minutes, electrodes are inserted to melt slag, and the slag is modified; the liquid steel is heated to a temperature of 1580 to 1600 DEG C, and alkalinity of the slag is controlled to be 0.8 to 1.3; under the condition that argon flow is 20 to 30 NL/min, argon is blown to the liquid steel for 25 to 30 minutes, and components of the slag are controlled. Therefore, compound inclusion particles with a low melting point and good plastic deformation are formed in the liquid steel and float upward rapidly, which is beneficial for effective removal of inclusions in the liquid steel, thereby substantially improving cleanliness of the liquid steel, obviously enhancing quality of billets, enabling defects of billets like looseness, cracks, segregationand non-metallic inclusions to be greatly reduced, the content of micro inclusions, especially inclusions of B type oxides and D type oxides, in steel products to be substantially reduced and the steel products to meet subsequent processing requirements of 70 high carbon steel wires and 60 Si2Mn spring steel.

A technology for manufacturing the Mg-alloy wheel hub includes such steps as preparing Mg alloy by additional use of RE element (0.5-2.0 wt.%) as part of its raw materials, smelting while adding the Mg-alloy coveriong agent prepared from MgCl2, CaF2, KCl, BaCl2 and MgO and the refining agent prepared from NaCl and KCl, preparing mould, spraying on inner surface of mould, casting, heat treating and surface treating. Its advantages are high strength, precision and surface finishing quality, high vibration damping effect, and saving oil.

The invention provides a niobium-titanium-nitrogen and titanium-nitrogen composite micro-alloyed HRB400E steel bar and a production method thereof, and belongs to the technical field of iron and steelsmelting. The niobium-titanium-nitrogen and titanium-nitrogen composite micro-alloyed HRB400E steel bar comprises, by mass, 0.21-0.25% of C, 0.50-0.65% of Si, 1.40-1.55% of Mn, not greater than 0.045% of P, not greater than 0.045% of S, 0.015-0.025% of Ti, 0.010-0.020% of Nb, 0.0070-0.0110% of N, and the balance Fe and other impurities. In the production method, ferrosilicon, silicomanganese anda carburant are added at the time of 1/4 tapping, and all alloys are added at the time of 3/4 tapping; the titanium-nitrogen alloy is added at an argon blowing station, and the argon blowing time is greater than or equal to 6 minutes; and high-casting-speed casting powder is adopted for continuous casting, a billet is heated, rolled and fed onto a cooling bed, and finally, the finished product isobtained. According to the niobium-titanium-nitrogen and titanium-nitrogen composite micro-alloyed HRB400E steel bar and the production method thereof, by adding the titanium-nitrogen alloy at the molten steel exposure positon of the argon blowing station, the titanium yield is increased; by reducing the influence of the niobium and titanium content on the quality of the high-casting-speed continuous casting billet, the titanium inclusion in steel is reduced, and the castability of molten steel meets requirements; and by adopting the high-casting-speed continuous casting powder, the cast billet quality is improved.

The invention discloses a pouring system for a hollow single crystal blade. The pouring system comprises a pouring cup, rectangular feeding blocks, blade wax pieces, crystal guide sections, a disc and a sprue. The sprue and the crystal guide sections are perpendicularly mounted on the disc. The upper end of the sprue is communicated with the pouring cup through a ceramic filter net. The lower end of the sprue is communicated with the crystal guide sections through ingates. The crystal guide sections are communicated with the lower ends of the blade wax pieces through spiral crystallizers. The upper ends of the blade wax pieces are communicated with the rectangular feeding blocks. The rectangular feeding blocks are communicated with the upper portion of the pouring cup through slag collecting gas vents. Feeding heads are further arranged at the upper ends of the blade wax pieces. The pouring system is reasonable in structure, the probability of inclusions, loosening, mixed crystals, a high-angle boundary, a low-angle boundary, zebra crystals and a crystal orientation deviation scrap rate of the single crystal blade is reduced, the product percent of pass is greatly increased, economic losses are reduced, the developing cycle is shortened, on time delivery of the blade is ensured, and the pouring system can be widely applied and popularized in the technical field of melted module precise casting.