3results about How to "Reduce surface cracks" patented technology

This utility model discloses a tube bending machine for vehicle frame production, including a base platform and a support frame fixed on top of it. A first cylinder is mounted on the top of the support frame and is connected to a forming mold located below the support frame. The base platform has forming wheels that cooperate with the forming mold. It also includes a heating mechanism, a tube fixing mechanism, and a cooling mechanism. The heating mechanism includes a movable seat, a second cylinder, a guide rail, and an electromagnetic heating component. The movable seat is slidably mounted on the side of the base platform via the guide rail. The second cylinder drives the movable seat to move in a direction closer to and away from the tube fixing mechanism. The electromagnetic heating component is fixed on the movable seat. The movable electromagnetic heating mechanism locally heats and softens the part of the tube to be bent, reducing bending resistance. Combined with the cooling mechanism, it quickly shapes the tube, reducing material springback and surface cracks, significantly improving the bending accuracy and yield of high-hardness tubes. At the same time, the integrated process shortens the tube processing cycle.

The application provides a silicon-carbon negative electrode material and a preparation method thereof, a negative electrode sheet and a battery. The silicon-carbon negative electrode material comprises a core and a carbon coating layer coated on the core; the core comprises a porous carbon framework and silicon particles, and the silicon particles are arranged in the pores of the porous carbon framework; there is a gap between the silicon particles and the surface of the pores of the porous carbon framework; in the core, the volume of the gap is V1, the volume of the silicon particles is V2, and V1 / V2 is 0.04-0.9. The silicon-carbon negative electrode material provided by the application has a buffer cavity reserved between the silicon particles and the pores of the porous carbon framework for silicon expansion, and can realize a silicon-carbon negative electrode material with low expansion and excellent electrical performance.

This invention provides a static extrusion forging mold structure for process nozzles, including an upper mold, a lower mold, an inner punch shaft-connected to the upper mold, and a pad shaft-connected to the lower mold. The forged product is located between the upper and lower molds. The shape and dimensions of the inner wall of the lower mold match the shape and dimensions of the outer wall of the forged product, and the shape and dimensions of the outer wall of the inner punch match the shape and dimensions of the inner wall of the forged product. The advantages of this invention are: using static extrusion forging technology to statically extrude the workpiece results in high-precision forging dimensions; the probability of surface cracks appearing during slow extrusion is greatly reduced; and raw materials are significantly saved compared to traditional processing methods.