S450J0 carbon steel plate sheet for engineering project

Manganese steel plate is subdivided according to material grade: Q345A, Q345B, Q345C, Q345D, Q345E, S450J0 carbon steel plate sheet. The main differences according to the classification are as follows: A needs no impact test, B needs room temperature impact test (20 degrees above zero), C needs zero degree impact test, D needs minus 20 degree impact test, and E needs minus 40 degree impact test. The most important characteristic of manganese steel plate is that under the condition of strong impact and extrusion, the surface layer rapidly hardens, but the core still maintains good toughness and plasticity, and the hardened layer has good wear resistance.

Hydrogen (H) is the most harmful element in general steel such as S450J0 carbon steel plate sheet. Hydrogen dissolved in steel will cause hydrogen embrittlement, white spots and other defects. Hydrogen, like oxygen and nitrogen, has very little solubility in solid steel. It dissolves into liquid steel at high temperature, and accumulates in the structure without time to escape when cooling, forming high-pressure micro pores, which greatly reduce the plasticity, toughness and fatigue strength of steel, and even cause cracks and brittle fracture in severe cases. "Hydrogen embrittlement" mainly occurs in martensitic steel, but not very prominent in ferrite steel, and generally increases with hardness and carbon content.

In recent years, after the completion of large-scale, high-speed and automation of steel rolling technology and equipment in the world, the rapid development of S450J0 carbon steel plate sheet high-precision rolling technology with the goal of improving product quality, expanding varieties, saving energy and reducing consumption, and increasing benefits. For example, in 2013, Bebon Iron and Steel's 4300 mm rolling mill, 5000 mm rolling mill and 3500 mm furnace coil rolling mill introduced foreign technology to further upgrade the company's S450J0 carbon steel plate sheet technical equipment.

According to different purposes, the thin steel sheets are rolled from billets of different materials. Commonly used materials include plain carbon steel, such as S450J0 carbon steel plate sheet, high-quality carbon steel, alloy structural steel, carbon tool steel, stainless steel, spring steel, and silicon steel for electrical purposes. The thin steel sheets are mainly used in the automobile industry, aviation industry, enamel industry, electrical industry, machinery industry and other sectors. In addition to delivery directly after rolling, there are also pickled, galvanized and tinned thin steel sheets.