Differences between 304/304L and 316/316L stainless steel

1. The difference between 304/304L and 316/316L stainless steel plates

Both grades are austenitic stainless steel, one of the most widely used and versatile types of steel. Since 304/304L stainless steel sheets and plates have excellent corrosion resistance, 316/316L sheets have a higher nickel content than 304 and 304L stainless steel sheets, so they have better corrosion resistance, especially in marine applications.


2. 316/316L stainless steel contains molybdenum and has better high temperature resistance

Reference chemical composition 316 stainless steel contains molybdenum, which is why 316/316L has better corrosion resistance than 304/304L, especially under 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 temperatures because molybdenum can easily react with high-valent sulfur ions and form sulfide.


3. What is stainless steel plate?

Stainless steel plates include stainless steel plates and acid-resistant steel plates, which are available in plates, rolls, sheets, etc. Commonly used grades are 304/304L, 316/316L, 321, etc.

Stainless steel has been developed for more than 90 years since the beginning of this century.


4. Reasons and methods of corrosion resistance of stainless steel plates

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 plate from oxidation and improve the corrosion resistance of the steel plate. When the passivation film breaks, corrosion resistance decreases.