5results about How to "Reduce porosity defects" patented technology

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 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.