20MnSi steel chemical composition and heat treatment

20MnSi plate is an alloy steel plate with good comprehensive properties, 20MnSi is a steel grade with high strength and good comprehensive properties, and is a building material. 20MnSi steel can be used in the production of steel structure, construction industry, machine parts and various standard parts.

Chemical composition of 20MnSi alloy steel plate:
Carbon (C) 0.17-0.23, Manganese (Mn) 1.30-1.70, Nickel (Ni)≤0.030, Silicon (Si) 0.40-0.70, Phosphorus (P)≤0.045, Sulfur (S)≤0.045, Chromium (Cr)≤ 0.030, Copper(Cu)≤0.030, C+1/6Mn≤0.5

20MnSi steel heat treatment process: 20MnSi steel belongs to hypoeutectoid steel and its matrix structure is ferrite and ten pearlite. Among them, the relative content of ferrite and pearlite, as well as their structure, distribution and grain size directly affect the mechanical properties of steel. The higher the pearlite content, the finer the pearlite group, the larger the grain size (the finer the grain), the higher the strength of the steel; vice versa. In the case of a fixed chemical composition, the internal structure of the steel directly affects the mechanical properties. While the rolling process changes the shape of the steel, it also changes the internal structure of the steel through structural changes such as work hardening, crystallization, and recovery, and ultimately determines the mechanical properties of the steel. Based on these theories, the content of alloying elements in small-sized steels should be low; the content of alloying elements in large-sized steels should be high, mainly due to two reasons. The first is the rolling reduction ratio. The rolling reduction ratio of small-gauge steel is large; the rolling reduction ratio of large-gauge steel is small and the rolling reduction ratio is large, which can make the structure of the steel dense and improve the mechanical properties of the steel. The second is the cooling rate. The cooling rate of large-sized steel is slow. The fast cooling rate is easy to refine the grains and improve the mechanical properties of the steel.