35results about How to "Avoid Bubble Defects" patented technology

The invention provides a casting coating for a coated sand mold and a preparing method of the casting coating. The casting coating comprises main components including, by mass percent, 49%-51% of zircon powder, 2%-3% of sodium bentonite, 1%-2% of polyvinyl alcohol, 5%-10% of silica sol, 0.2%-0.35% of sodium carboxymethyl cellulose (CMC), 0.2%-0.35% of a penetrating agent JFC, 0.3%-0.4% of an anti-foaming agent and the balance water. The prepared casting coating for the coated sand mold is high in drying speed and smooth in coasting, sand cannot be stuck to the casting obtained after coated sand casting, the coating is resistant to molten steel scouring, the surface finish degree is high, and the quality is good.

The invention discloses an oscillating device of a locating clip in a copper-aluminum composite busbar gating system. The locating clip comprises a primary connecting piece and a secondary connecting piece both of which can perform open and close movements, as well as a pair of clamp splices respectively arranged on the primary connecting piece and the secondary connecting piece through flexible pieces. The oscillating device comprises an oscillator fixed on the pair of clamp splices and used for driving the clamp splices to oscillation up and down. When the clamp splices hold a copper-aluminum composite busbar, gas mixed into aluminum liquid in a copper tube can be discharged by up and down oscillation of the copper-aluminum composite busbar with the clamp splices through the oscillator, thus avoiding bubble defects, improving the density of aluminum products, ensuring crystal lattices of aluminum products to be uniform, enhancing the combination between the copper tube and aluminum products, and also increasing the metal ductility of the copper-aluminum composite busbar, and guaranteeing the product quality.

The invention relates to a pretreatment method for silanization, which is characterized in before performing silanization to a wafer, performing the following steps: heating the wafer, and introducing nitrogen to purge; introducing diluted silanization agent gas; and introducing the nitrogen to purge continuously, and exhausting the gas. The invention further relates to a silanization method comprising the pretreatment method.

The invention relates to an interconnecting wire structure and a forming method thereof. A semiconductor substrate is provided; the forming method of the interconnecting wire structure comprises the steps of forming multiple independent interconnecting wires on the semiconductor substrate, wherein grooves are formed between adjacent interconnecting wires; forming a first interlayer dielectric layer to cover the interconnecting wires, and filling a groove in part of the first interlayer dielectric layer until an opening is formed; forming a second interlayer dielectric layer to cover the first interlayer dielectric layer, wherein the opening is sealed by the second interlayer dielectric layer to form an air gap; flattening the second interlayer dielectric layer. The interconnecting wire structure formed by the forming method is improved in quality, and the forming method is simple in process and low in process cost.

The invention discloses a device for removing low molecular substances in casting PBX slurry. The device comprises a storage hopper, a distribution tray and a receiving hopper, wherein the storage hopper and the receiving hopper are connected into an integral body in an up-and-down sealing mode; the distribution tray is connected and sealed in a discharge port end surface of the storage hopper; distribution holes with diameters of 2-8mm are distributed in the distribution tray; the neck of the discharge port of the storage hopper is provided with a plug valve; the side surface of the receiving hopper is connected with a vacuum extractor, and the neck of the discharge port is provided with a plug valve; and when the two plug valves are closed simultaneously, the receiving hopper can become a closed space. The invention also discloses a method for removing low molecular substances in casting PBX slurry by using the device. The invention can be used for successfully removing air, styrene and other low molecular substances in the casting PBX slurry, and avoid the defects of bubbles in the slurry, thereby enhancing the internal quality and safety performance of the casting PBX slurry. The invention has wide application prospects in conventional warhead PBX slurry.

The invention relates to a method for reducing a bubble defect of a slab Cr-containing steel grade casting blank. Argon gas in a tundish is operated at a small flow rate, the argon gas flow rate of astopper rod in the tundish is less than or equal to 2.0 NL / min, and the argon gas flow rate of an upper nozzle is less than or equal to 2.0 NL / min; in the casting process, the minimum single-flow steel passing is not less than 2.4 tons / min; when the slab width is less than or equal to 1500 mm, three-hole immersive nozzle is used for continuous casting, the inclination angle of the holes in both sides is at 15 degrees, and the area ratio of vertical hole steel passing to the total steel passing is 5-18%; when the slab width is larger than 1500 mm and is small than or equal to 2200 mm, a two-hole immersive nozzle without vertical holes are used for continuous casting, and the inclination angle of the nozzle of water in the two holes are at 20 degrees; the superheat degree of molten steel ofthe tundish is not less than 12 DEG C; and the distance from the top edge of a discharge hole of the immersive nozzle to the liquid level of the molten steel in a crystallizer is 100-160 mm. Accordingto the method, the bubble defect generated by steel grades containing Cr more than or equal to 0.15% is avoided, and the defect of edge portion "peeling"-like formed by bubble exposure rolling elongation in the casting blank rolling process is eliminated. The product quality of the steel grade is improved.