10results about How to "Reduce porosity defects" patented technology

According to the scheme, the brake disc casting device comprises an upper sand mold and a lower sand mold located below the upper sand mold, the upper sand mold and the lower sand mold are vertically combined to form an annular mold cavity, a vertically-through first flow channel is formed in the upper sand mold, a second flow channel is formed in the lower sand mold, one side of the second flow channel is communicated with the first flow channel to form a pouring gate, and the other side of the second flow channel is communicated with the pouring gate. The other side of the second runner is communicated with the cavity so that molten metal can flow into the cavity through the pouring gate, the upper sand mold is provided with at least one overflow groove with a downward opening, and the overflow groove is communicated with the top of the cavity; the shielding structure is arranged on the lower sand mold and located in the mold cavity, the shielding structure shields part of the opening of the overflow groove, the overflow groove is formed in the top of the mold cavity, bubbles and waste residues in molten metal can be naturally accumulated in the overflow groove, the bubbles and the waste residues in the mold cavity are reduced, and the production efficiency is improved. And therefore, the pore defect problem of the upper disc surface of the formed casting is reduced, and the process yield is improved.

The invention discloses a method for improving the structure and performance of a 6063 aluminum alloy formed through selective laser melting, and belongs to the technical field of selective laser melting. Titanium powder and zirconium hydride in a certain proportion are selected as doping agents, the doping agents are evenly mixed with 6063 aluminum alloy powder through a ball milling method, and then drying and dehumidification are conducted; and the mixed alloy powder is put into selected-area laser melting equipment, manufacturing is carried out on the surface of a base material under inert gas protection, and the 6063 aluminum alloy is obtained after laser, scanning, powder laying and deposition. According to the method, the microstructure and the mechanical property of the selective laser melting forming 6063 aluminum alloy are obviously improved, so that the selective laser melting forming 6063 aluminum alloy meets the industrial performance requirement of SLM, and good market competitiveness is achieved.

The invention relates to the technical field of castable, in particular to high-performance tundish cover castable based on high-aluminum ceramic chip recycled aggregate and a preparation method of the high-performance tundish cover castable. The castable comprises high-aluminum ceramic chip recycled aggregate, modified hollow alumina microspheres, andalusite and other components, and through roasting stabilization treatment of the recycled aggregate and multi-layer coating modification of the microspheres, the problems of poor heat preservation property and concentrated thermal stress caused by high doping amount of the recycled aggregate are solved. The andalusite cooperates with the modified microbeads to optimize aggregate-andalusite-microbead three-phase interface combination by virtue of the low-expansion characteristic and the active surface, so that the thermal shock resistance and the structural compactness are enhanced. The product has excellent heat preservation and heat insulation performance, high strength and slag corrosion resistance, resource efficient utilization of waste high-aluminum ceramic chips is achieved, and the service life of the tundish cover is prolonged.

This invention relates to the field of welding materials technology, and particularly to a high-performance aluminum-lithium alloy flux-cored welding wire and its preparation method. The high-performance aluminum-lithium alloy flux-cored welding wire comprises: an aluminum-based metal strip outer sheath; and flux powder filled within the outer sheath. The flux powder includes deoxidizing components, alloy components, arc-stabilizing components, slag-forming components, and binding components. The alloy components of the aluminum-lithium alloy flux-cored welding wire, by mass percentage, include: Cu: 3.7%-4.3%, Li: 0.8%-1.5%, Mg: 0.25%-1%, Zr: 0.1%-0.16%, with the balance being Al and unavoidable impurities. The burn-off rate of active elements is significantly reduced, and the composition control accuracy reaches ±0.05%. The flux structure encapsulates highly active elements such as Li, Mg, and Zr in powder form within the aluminum-based outer sheath, avoiding high-temperature volatilization and oxidation in traditional smelting processes. These elements are released only during welding, achieving precise composition control and enabling the stable preparation of aluminum-lithium alloy welding wires with high Li content (2%-3%).

This application relates to a mold and casting process for casting end caps of shell-type hydraulic valve bodies, belonging to the technical field of casting processing. The mold includes a mold body with a cavity formed within it. A runner sand core is disposed within the cavity and fixedly connected to the mold body. A gating port is provided at the bottom of the mold body and communicates with the cavity. The bottom gating assembly includes a sprue base plate and a vertical gating pipe. A horizontal runner is provided within the sprue base plate, with its length direction along the horizontal direction. The vertical gating pipe is vertically positioned above the sprue base plate, with its lower end connected to the sprue base plate and communicating with the horizontal runner. The mold body is fixed to the sprue base plate, and the gating port communicates with the horizontal runner. This application reduces the occurrence of splashing, turbulence, and air entrapment of molten metal within the cavity, thereby reducing the generation of secondary oxidation inclusions and porosity defects inside the casting, which improves the final casting quality.

The invention relates to the technical field of alloy coating materials, and particularly discloses an anti-oxidation coating for a high-pressure hot-pressing mold and a preparation method of the anti-oxidation coating. The high-pressure hot-pressing mold anti-oxidation coating comprises a transition layer and a functional layer which are sequentially arranged from a mold base body to the outside, the transition layer is a TiN-SiC gradient composite layer, the functional layer takes Al2O3-NiCrAlY as a base body, and nano ZrB2 and rare earth CeO2 which are subjected to double modification treatment are compositely doped; and the dual-modified nano ZrB2 is ZrB2 particles which are coated with a silane coupling agent KH-560 and a NiCr alloy. The anti-oxidation coating of the high-pressure hot-pressing mold has both oxidation resistance and wear resistance, and the high-temperature hardness stability and wear resistance of the anti-oxidation coating are effectively enhanced.

The utility model relates to a composite material repair paving layer curing device which is characterized in that a repair paving layer is adhered to an area to be repaired, and the hot end of a thermocouple is transversely adhered to the edge of the repair paving layer in a sealing manner through a high-temperature adhesive tape; the stripping layer covers the repair paving layer and the thermocouple; the porous isolating membrane covers the stripping layer; the glass fiber cloth covers a porous isolating membrane; the non-porous isolating membrane covers the glass fiber cloth; the pressure equalizing plate is covered with a non-porous isolating membrane; the electric blanket covers the pressure equalizing plate; the breathing material covers the electric blanket; the vacuum base is diagonally placed on the breathing material; the vacuum film is bonded with a to-be-repaired part through a double-sided sealing adhesive tape to form a vacuum sealing bag and is connected with the vacuum base through a vacuum suction nozzle, and the vacuum suction nozzle is connected with an external vacuum pump. Compared with the prior art, the device has the advantages of high fitting degree of a repaired surface, high flatness, high reliability and the like.

The application relates to the technical field of alloy coating materials, and particularly discloses a high-pressure hot-pressing die oxidation-resistant coating and a preparation method thereof. The high-pressure hot-pressing die oxidation-resistant coating comprises a transition layer and a functional layer arranged outward from a die base body, the transition layer is a TiN-SiC gradient composite layer, the functional layer takes Al2O3-NiCrAlY as a base body, and is compounded and doped with double-modified nano ZrB2 and rare earth CeO2; the double-modified nano ZrB2 is ZrB2 particles coated with a silane coupling agent KH-560 and a NiCr alloy. The high-pressure hot-pressing die oxidation-resistant coating has oxidation resistance and wear resistance, and effectively enhances the high-temperature hardness stability and wear resistance of the oxidation-resistant coating.

This utility model discloses a cooling bed with an auxiliary function to reduce porosity in microchannel aluminum flat tubes, relating to the field of microchannel aluminum flat tube production technology. It includes a frame and support legs. The top of the support legs is fixedly connected to the frame, and a conveying roller is rotatably connected to the inner side of the frame. A cleaning mechanism is provided on the side of the conveying roller, and a fixing plate is fixedly connected to one end of the frame. When the conveying roller rotates and conveys the aluminum flat tube, the system drives a reciprocating screw via a motor, causing the cleaning plate and brush on the slider to reciprocate. This design causes relative motion between the brush and the rotating surface of the conveying roller, effectively removing alumina particles adhering to the roller surface. This continuous cleaning mechanism ensures that the surface of the conveying roller always maintains good contact with the bottom of the aluminum flat tube, guaranteeing the uniformity of the cooling process. Uniform cooling facilitates the timely discharge of gas from the bottom of the aluminum flat tube, thereby significantly reducing porosity defects at the bottom of the aluminum flat tube.

A laser welding method, milling single edge groove on two workpieces to be welded respectively; assembling and aligning the two workpieces to be welded after cleaning; using laser swing filler wire welding method in heat conduction welding mode to carry out non-penetration welding, only using filler wire metal to fill the upper groove of the test plate, obtaining the first filler wire welding seam with obvious excess height; using laser self-melting welding method in keyhole welding mode to carry out full penetration welding, laser beam penetrating the first filler wire welding seam and the whole workpiece thickness at the same time, obtaining the second full penetration welding seam. In the process of the second full penetration welding, the upper first filling metal part is partially melted and moves to the lower part under the action of the melt pool convection, and under the action of surface tension, the upper surface of the final weld has only slightly reduced excess height, and the lower surface forms obvious excess height.