Difference between 304/304L and 316/316L stainless steel rods

Stainless steel has been developed for more than 90 years since the beginning of this century. The corrosion resistance of stainless steel mainly depends on its alloy composition (chromium, nickel, titanium, silicon, aluminum, etc.), and the internal structure is mainly chromium (Cr). Chromium has high chemical stability and can form a passivation film on the surface of steel to isolate the metal from the outside. Protect the steel bar from oxidation and improve the corrosion resistance of the steel bar. When the passivation film is broken, the corrosion resistance is reduced.

Both grades 304 and 316 are austenitic stainless steel, which is one of the most widely used steel types. Due to the excellent corrosion resistance of 304/304L stainless steel bars and bars, 316/316L bars have a higher nickel content than 304 and 304L stainless steel bars, so their corrosion resistance is better, especially in Marine applications.

316/316L stainless steel contains molybdenum, which has better high temperature resistance, reference chemical composition 316 stainless steel contains molybdenum element, which is the reason 316/316L has better corrosion resistance than 304/304L, especially at high temperature conditions. Therefore, engineers usually choose 316 materials in high temperature environments. However, if the environment contains sulfuric acid, do not use 316/316L at high temperature, because molybdenum easily reacts with high-valence sulfur ions and forms sulfides. Including stainless steel rods and acid-resistant steel rod, bar, wire and other forms, commonly used brand 304/304L, 316/316L, 303, etc., there is a need to consult customer service ~