The main manufacturing process of S355N steel plate

The chemical composition of S355N steel plate is mainly composed of a variety of elements, including carbon (C), silicon (Si), manganese (Mn), phosphorus (P), sulfur (S), chromium (Cr), molybdenum (Mo), etc. In addition, it may also contain elements such as nickel (Ni), copper (Cu), niobium (Nb), vanadium (V), titanium (Ti), aluminum (Alt), and nitrogen (N). The specific ingredient content has certain range restrictions, for example, the carbon content should be ≤0.20, the silicon content should be ≤0.50, the manganese content should be between 0.9 and 1.65, the phosphorus content should be ≤0.030, the sulfur content should be ≤0.025, etc.

Each of these elements plays an important role in the steel plate. For example, carbon is the main element responsible for increasing the strength and hardness of the steel plate; silicon and manganese, as alloying elements, can further improve the strength and hardness of the steel plate; phosphorus and sulfur are impurity elements, and their presence will reduce the toughness and corrosion resistance of the steel plate. , so its content needs to be strictly controlled during the production process; chromium and molybdenum, as alloy elements, play an important role in improving the corrosion resistance and high-temperature strength of steel plates.

The main manufacturing process of S355N steel plate involves multiple precise process links. The specific steps are as follows:
Raw material preparation: Select appropriate steel raw materials, such as iron ore, scrap steel, etc., to ensure that their chemical composition meets the specified requirements.
Smelting: Smelting is carried out using vacuum smelting, electric furnace or converter and other process conditions to ensure the purity of molten steel and the accuracy of its composition. At this stage, appropriate amounts of alloying elements are added to adjust the mechanical properties and welding properties of the steel.
Continuous casting: Inject the smelted molten steel into the continuous casting mold, and form a steel billet of a certain specification by controlling the appropriate cooling rate and billet temperature.
Rolling: Rolling the continuously cast steel billet into steel plates with the required thickness, width and length. During the rolling process, the rolling process and temperature need to be precisely controlled to ensure the thickness, width and length accuracy of the steel plate as well as the uniformity of the internal structure.
Heat treatment: As needed, the rolled steel plate is heat treated, such as quenching, tempering, normalizing, etc., to adjust its mechanical properties and microstructure.
Surface treatment: Coating, plating, etc. are applied to the surface of the steel plate to improve its corrosion resistance and service life.
Quality inspection: Conduct quality inspection on finished steel plates, including inspection of appearance, size, chemical composition, mechanical properties, etc. Only qualified steel plates can be used out of the factory.
During the entire manufacturing process, the parameters and conditions of each link need to be strictly controlled to ensure that the quality and performance of the S355N steel plate meet the specified requirements.