There are many types of stainless steel products.
Stainless steel does not rust in weak corrosive media such as air, fresh water, etc., and resists corrosion in corrosive solid media such as acid, alkali, and salt solutions.
The chromium contained in the surface of the formation, a skinny chromium-rich oxide film, isolates the steel and the outside world of oxygen, thus preventing rusting. Stainless steel is actually an iron-based high-alloy steel.

There are many types of stainless steel, which can be divided into chromium-manganese-nickel stainless steel, chromium-nickel stainless steel, and chromium stainless steel according to their chemical compositions, corresponding to the 200, 300, and 400 series of the American AISI standards.
The content of metal composition has a big difference for different types of stainless steel. Usually, the difference between the types of stainless steel is mainly due to nickel content differences. As a standard, 400 series stainless steel contains the least amount of nickel, not more than 0.75%.
400 series stainless steel has good resistance to high-temperature oxidation, a small coefficient of thermal expansion, low nickel content, and low production costs. Still, simultaneously, the 400 series stainless steel molding performance tensile strength is lower than the 300 series stainless steel products, resulting in the application of its products being more limited.
400 series stainless steel production fluctuation growth
From 2013 to 2022, China’s 400-series stainless steel production fluctuation growth. In 2021, the national Cr steel (400-series) production of 6.267 million tons, compared with the previous year, increased by 342,000 tons, and the growth rate slowed. In 2022, 400-series stainless steel production dropped, and the annual output fell to 5.6 million tons.
400 series stainless steel application prospects
400 series stainless steel is almost free of precious nickel, low cost, excellent performance, and is mainly used in civil products. 400 series stainless steel in electronic products, building roofing and decorative, automotive exhaust systems, and household appliances such as washing machine tubes, containers, outdoor water tanks, etc., have an extensive range of uses, of which in the kitchen utensils products, home appliances, decorative, automotive exhaust systems, petrochemicals, and other civil and industrial fields can partially replace the 300 series austenitic products. The area can partially replace the 300-series austenitic stainless steel.
With the increase of R & D investment, 400-series stainless steel is expected to be more in the roofing system, heat transfer system, building materials, guardrails, automotive structural components, elevators, pipelines, nuclear power, and other fields to broaden the application.