3results about How to "Avoid edge cracking" patented technology

This invention discloses a forming process for a perforated feature on a sheet metal, comprising the steps of: drawing the sheet metal to form a convex bulge; pressing the convex bulge to reduce its diameter and gradually bring its sidewalls closer to vertical, wherein the convex bulge protrudes upwards during the pressing process; pre-punching a hole at the convex bulge location to obtain a blank hole; and flanging and shaping the blank hole. This invention also discloses a sheet metal with a perforated feature, which is manufactured using the aforementioned forming process for a perforated feature on a sheet metal.

This application discloses a complete production method for ultra-thin high-grade non-oriented silicon steel and its acid continuous rolling combined with 20-roll precision cold rolling. The thickness of the non-oriented silicon steel is (0.05~0.15)±0.002mm. The production method includes: heating: homogenization temperature 1000~1140℃; hot rolling: the initial rolling temperature of the first finishing rolling pass ≥950℃, the final rolling temperature of the last finishing rolling pass 850±15℃, and the hot-rolled plate thickness 1.80~2.30mm; coiling temperature 630±15℃; pickling and continuous cold rolling: pickling and multi-pass continuous cold rolling are performed using a multi-stand pickling and continuous cold rolling mill, and the hardened plate thickness is 0.2~0.35mm; normalizing the hardened plate: normalizing the hardened plate in a normalizing furnace to obtain a normalized hardened plate; normalizing temperature 850~950℃; 20-roll cold finishing; annealing: annealing temperature 900~1000℃, annealing time 40~120s.

The application discloses a high-strength magnesium alloy plate preparation method, and chemical components of the magnesium alloy plate are as follows in percentage by mass: 5.5-6.0% of zinc, 2.0-2.5% of ytterbium, 0.6-1.0% of zirconium, and the rest of magnesium. The preparation method involves four steps of alloy smelting, solid solution, inclined rolling and finishing. When the total reduction reaches 80-85% of the initial thickness, the magnesium alloy plate obtained has a room-temperature tensile yield strength of 350-390 MPa and a tensile strength of 370-430 MPa. The magnesium alloy plate prepared by the technology has the characteristics of high strength and less edge cracking, and has the technical advantages of low cost and high efficiency.