6results about How to "Avoid edge cracking" patented technology

The invention relates to an extrusion and rolling method for a fine-grain AlN / AZ91D magnesium-based composite material. The extrusion and rolling method comprises the steps of solution treatment, extrusion treatment, homogenization treatment, multi-pass cold rolling, annealing treatment between passes and final annealing treatment. Meanwhile, the invention further provides the fine grain AlN / AZ91D magnesium-based composite material obtained through the extruding and rolling method, the high-performance magnesium alloy cold-rolled plate which is uniform in structure, fine in grain and good in formability is finally obtained through the technological method, the edge crack problem in the rolling process is avoided through the technology, and meanwhile the mechanical property of the magnesium alloy is greatly improved.

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.

The invention discloses a crack-resistant pure-color brick with secondary distribution and a preparation method thereof, comprising the following steps: mixing a base material blank and a surface material blank according to a predetermined ratio, and obtaining corresponding slurry after ball milling; respectively obtaining a base material powder and a surface material powder after spray drying and sieving; pressing and molding after positive secondary distribution to obtain a brick blank; applying a glaze on the surface of the brick blank, and finally sending the brick blank into a roller kiln for firing; the invention controls the moisture content of the base material powder to 6.3-6.8%, and the moisture content of the surface material powder to 5.3-5.8%, so that appropriate bonding force can be formed between powder particles, which is conducive to molding and pressing, and at the same time improves the strength of the brick blank, avoiding edge cracking and edge opening; pressing and molding the base material powder and the surface material powder after secondary distribution through a distribution system, so that the base material powder and the surface material powder can be more closely combined, thereby increasing the density and strength of the brick blank.

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 invention discloses a production method for reducing edge cracks of high-magnetic-induction oriented silicon steel, and relates to the technical field of oriented silicon steel production and manufacturing, and the production method comprises the following steps: S1, carrying out normalizing treatment, acid pickling and cold rolling on a hot rolled steel coil to obtain a cold-rolled steel plate; s2, carrying out decarburization annealing and nitriding treatment on the cold-rolled steel sheet, extruding the cold-rolled steel sheet, coating a magnesium oxide coating, and carrying out high-temperature annealing to obtain an annealed steel coil; and S3, the annealed steel coil is subjected to stretching flattening annealing and laser nicking treatment, and the high-magnetic-induction oriented silicon steel is obtained. According to the production method disclosed by the invention, the cracking occurrence rate of the edge part of the steel coil after high-temperature annealing is greatly reduced through a low-cost production method.

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.