1. Three product series of stainless steel

Stainless steel can be roughly divided into three categories: 200 series, 300 series and 400 series. Among them, 300 series is the most commonly used. 200 series and 400 series are substitutes for 300 series to a certain extent. Strictly speaking, 400 series is not called stainless steel, but stainless iron because it does not contain nickel, so it can be attracted by magnets. 200 series and 300 series contain nickel, so they are not magnetic and cannot be attracted by magnets.

304 is the most common variety in the 300 series, so the price trend of the entire stainless steel can generally be judged from the price changes of 304. The 200 series contains less nickel, the 400 series does not contain nickel, and the 300 series contains the most nickel, so the 300 series is the most affected by the nickel price.

The 300 series can be simply divided into 304, 304L316316L, 321, 30953105, etc. The basis for distinction is the different contents of various metal elements. The characteristics of stainless steel with different contents are also different. The difference between 304 and 304 lies in the different carbon (C) content. The one with L means low carbon content, also called low carbon 316 and 316 are the same.

2. Definition of stainless steel

Stainless steel is a kind of high alloy steel that can resist corrosion. It has a beautiful surface and does not need to be plated or painted. Therefore, many machinery factories often do not do any paint treatment to show that they are stainless steel, while black materials (the so-called black materials are the name of general steel) must be rust-proofed.

Stainless steel is a type of steel. Steel refers to steel with a carbon (C) content of less than 2%, and iron is greater than 2%. During the steel smelting process, alloy elements such as chromium (Cr), nickel (Ni), manganese (Mn), silicon (Si), titanium (Ti), and molybdenum (Mo) are added to improve the performance of the steel and make it corrosion-resistant (i.e. rust-resistant), which is what we often call stainless steel.