202 stainless steel is one of the 200 series stainless steels. The chemical composition is iron, manganese, aluminum, sodium, carbon, lime, carbon dioxide, bromine, and the density is 7.938 kg/cubic decimeter. The nickel content of 202 stainless steel is generally below 4%, and the manganese content is about 8%, which belongs to low nickel and high manganese stainless steel.
202 stainless steel is often associated with 304 stainless steel, mainly because both belong to the austenitic structure, without magnetism, and there is little difference in appearance. The most important difference lies in the content of the chemical element nickel, which causes the two to be in Huge difference in performance and price.

High-quality carbon structural steel: In addition to carbon (C) elements and a certain amount of silicon (Si) (generally no more than 0.40%) and manganese (Mn) (generally no more than 0.80%) for deoxidation, the steel can be as high as 1.20% %) alloying elements, without other alloying elements (except residual elements). Such steels must guarantee both chemical composition and mechanical properties. The content of sulfur (S) and phosphorus (P) impurity elements is generally controlled below 0.035%. If it is controlled below 0.030%, it is called high-grade high-quality steel, and “A” should be added after its grade, such as 20A; if P is controlled below 0.025% and S is controlled below 0.020%, it is called super-high-quality steel, and its grade should be followed by adding "E" for distinction. For other residual alloy elements brought into the steel from raw materials, such as chromium (Cr), nickel (Ni), copper (Cu), etc., the content is generally controlled at Cr≤0.25%, Ni≤0.30%, Cu≤0.25%. Some grades of manganese (Mn) content reach 1.40%, called manganese steel.

​By the end of 2021, the steel output of Shandong Province was 79.94 million tons, ranking third in the country, with an output value of about 500 billion yuan. There are a wide range of steel products, and plate and section steel occupy an important position. Among the 22 categories of steel products, Shandong enterprises occupy 19 kinds. By the end of 2020, the production capacity of plate and section steel was 42million tons, accounting for about 45%; The production capacity of construction steel is about 28million tons, accounting for about 30%; The production capacity of special steel is 17 million tons, accounting for about 19%; Other production capacity accounts for about 6%.