6results about How to "Reduce inclusion defects" patented technology

The utility model relates to the technical field of magnesium alloy metallurgy, in particular to a vacuum liquid guide device for magnesium alloy smelting, which comprises a sealing crucible, a sealing cover, a liquid guide pipe, a vacuum pipe, a connecting pipe, an argon bottle and a vacuum pressure gauge, the sealing cover is connected with the sealing crucible and located at the top of the sealing crucible, the liquid guide pipe is connected with the sealing cover, penetrates through the sealing cover and the vacuum pipe to be fixedly connected with the sealing cover, penetrates through the sealing cover and the connecting pipe to be connected with the sealing cover and located at the top of the sealing cover, and the argon bottle is connected with the connecting pipe and located on the side, away from the sealing crucible, of the connecting pipe. The vacuum pressure gauge is fixedly connected with the sealing cover and located on the top of the sealing cover, and the problems that in traditional magnesium alloy smelting, magnesium is prone to oxidation, impurities are not removed thoroughly, and the purity, performance and quality of alloy are reduced are solved.

This invention belongs to the field of directional solidification of high-temperature alloys, and provides an engineering-applicable anti-gravity effect single-crystal high-temperature alloy directional solidification growth device and its application, which reduces the formation of interdendritic segregation, avoids the formation of defects such as freckles, and meets the actual needs of high-temperature alloy directional solidification blade preparation. The device structure is as follows: a vacuum induction furnace is set at the bottom of the device, and a crucible is placed inside it. The crucible is located on a crucible lifting mechanism, and a graphite holding furnace is set above the crucible. A pulling mechanism is set at the top of the device, and a water-cooling plate is set below it. The top of the mold shell has a seed crystal mounting port for installing the seed crystal, and the bottom has an alloy liquid inlet. After the mold shell and the seed crystal are assembled, they are fixed on the water-cooling plate by a fixing clamp. The device also includes a heat insulation baffle and a vacuum system. The heat insulation baffle with through holes is set parallel to the crucible above the graphite holding furnace, and the inner diameter of the through holes of the heat insulation baffle is 10-20 mm larger than the maximum outer diameter of the mold shell.

The invention discloses an aluminum-titanium intermediate alloy wire rod for grain structure regulation and control, the intermediate alloy comprises the following raw materials in percentage: 5.5-6.5 wt.% of titanium, 0.1-0.3 wt.% of boron, 0.1-0.5 wt.% of rare earth element and the balance of aluminum, in the preparation process of the intermediate alloy, the intermediate alloy can be added into molten aluminum in a mode of continuous addition in a furnace or added through a proton diffuser, so that continuous and uniform addition is realized; the method is suitable for modern continuous production, the number of effective nucleation particles in molten aluminum is increased, through online adding of a proton diffuser, particles in intermediate alloy are released in a high-activity state, the grain refinement effect is enhanced, stability is improved, the core surface grain size difference of a casting blank is reduced, and the uniformity and extensibility of the internal structure of the aluminum alloy are improved; and the high-activity particles can preferentially act with electrolyzed or impurities in the molten aluminum to promote the electrolyzed or impurities to gather and float upwards, so that the cleanliness of the molten aluminum is improved, and the defects of electrolyzed or impurities are reduced.

This invention discloses a 635MPa grade niobium-vanadium-chromium composite reinforced high-performance steel bar and its smelting method. By controlling the chemical composition and V / N mass ratio of the steel bar within the range of 3.35 to 3.75, and employing a multi-element composite strengthening formula of niobium, vanadium, and chromium to replace the traditional single vanadium-nitrogen alloy addition mode, production costs are reduced. During the smelting process, a dedicated dry powder stirring device is used to pre-mix the microalloying reinforcing agent, achieving uniform mixing of powder components and removal of magnetic impurities. Simultaneously, a composite desulfurizing agent is introduced and a step-by-step addition process is adopted, combined with a gradient ladle bottom-blowing argon stirring system, to effectively reduce the sulfur content in the steel. The steel bar prepared by this invention has a uniform microstructure, high grain size, and excellent mechanical properties such as tensile strength, yield strength, strength-to-yield ratio, and elongation. It exhibits good product consistency, low production costs, and can stably mass-produce high-performance 635MPa grade high-strength earthquake-resistant steel bars.

The invention relates to the technical field of rotating target materials, in particular to a centrifugal binding method of a large-size ITO rotating target material, which comprises the following steps: step 1, pretreatment of a contact surface: degreasing and cleaning the inner wall of the ITO target material and the outer surface of a metal back tube, and then respectively sputtering nickel or copper for metallization treatment, with the thickness of a sputtering layer being 0.5-2 microns; step 2, assembling and positioning: coaxially assembling to form a 0.1-0.3 mm uniform binding gap, and mounting a sealing check ring; 3, centrifugal binding is conducted, specifically, rotation is conducted at the rotating speed of 800-1500 r / min, high-purity indium solder at the temperature of 180-200 DEG C is injected, and inert gas protection is conducted; and 4, cooling molding: cooling to room temperature at 5-10 DEG C / min. Uniform filling of the welding flux is achieved through centrifugal force, the binding rate reaches 99% or above, the binding strength is larger than or equal to 25 MPa, the problems that a large-size target material is large in binding defect number and low in strength are effectively solved, and the method is suitable for industrial production.

The utility model provides a riser for foam full mold casting. The riser comprises a first foam block, a filter screen and a second foam block, the first foam block is of a rectangular structure; the filter screen is arranged at the bottom end of the first foam block; the second foam block is connected to the lower surface of the filter screen, and the area of the cross section of the second foam block in the vertical direction is gradually reduced from top to bottom. According to the dead head for foam full mold casting, the foam dead head with the filter screen is provided, after molten metal is poured down from top to bottom, slag and impurities are blocked by the filter screen and cannot enter a mold cavity, the situation that the defects are mixed in a casting is reduced, the forming quality of the metal casting is guaranteed, and the defective rate is reduced; and the gradually-reduced section design of the second foam block can guide the flowing speed of the molten metal to be gradually reduced, the turbulence risk is reduced, and the feeding effect is favorably optimized.