The Difference Between 304 Stainless Steel And 316 Stainless Steel

Stainless steel has penetrated into every aspect of everyone's life. 304 stainless steel is also widely known as food-grade stainless steel. Now 316 Stainless Steel Strip Supplier often promote 316 Stainless Steel Tubing. What is the difference between them?

Stainless steel is a type of alloy steel. We usually say "stainless steel", the full name is "stainless acid-resistant steel". To prevent the steel from rusting, it is actually very simple, just add some metal impurities to make alloy steel (such as adding chromium). But if it does not rust, it only means that it will not be corroded by air, and its ability is still too poor. So we also need it to resist chemical corrosion, so "stainless acid-resistant steel" appeared. If you want to make stainless acid-resistant steel, you need to add a lot of metals. Different metal formulas form different stainless steels.

Both 304 and 316 are austenitic stainless steel. Stainless steel is often divided into martensitic steel, ferritic steel, austenitic steel, austenitic-ferrite (dual phase) stainless steel, precipitation hardening stainless steel, etc. In addition, it can be divided into chromium stainless steel, chromium-nickel stainless steel and chromium manganese nitrogen stainless steel. Among them, austenitic stainless steel has the best comprehensive performance and no magnetism, so it is the most widely used in our daily life. 304 and 316 are all austenitic stainless steels.

The anti-corrosion ability of 304 stainless steel is already very strong. It is positioned as a "food grade" metal by the national standard-normal contact with water, tea, coffee, milk, oil, salt, sauce and vinegar, etc. is no problem. 316 stainless steel is a further upgrade on this basis (controlling the proportion of impurities, adding molybdenum) to make the corrosion resistance stronger. In addition to oil, salt, sauce, vinegar and tea, it can resist all kinds of strong acids and alkalis. Not only that, 316 stainless steel has better adaptability to the environment, and the temperature is too high or too low, which does not affect the corrosion resistance of 316 stainless steel pipes. But 316 production costs are higher and prices are higher.

Cold Rolled 304 Stainless Steel Sheets

304: 304 Seamless Stainless Steel Pipe. Products such as: corrosion-resistant containers, tableware, furniture, railings, medical equipment. The standard composition is 18% chromium plus 8% nickel. It is a non-magnetic stainless steel that cannot be changed by heat treatment. The GB brand is 06Cr19Ni10.

304 L: The same characteristics as 304, low carbon, so it is more corrosion resistant and easy to heat treatment, but the mechanical properties are poor.

304 N: The same characteristics as 304, it is a kind of nitrogen-containing stainless steel. Nitrogen is added to improve the strength of the steel.

316: After 304, the second most widely used steel grade is mainly used in the food industry, watch accessories, pharmaceutical industry and surgical equipment. The addition of molybdenum makes it obtain a special structure that resists corrosion. Because it has better resistance to chloride corrosion than 304, it is also used as "marine steel". SS316 is commonly used in nuclear fuel recovery devices.

316 L: Low-carbon, so it is more corrosion-resistant and easy to heat treatment. Products such as: chemical processing equipment, nuclear power generators, refrigerant storage tanks.

For food steel, 304 is enough, and there are almost no defects; the use of 316 in this regard is purely small, and the aspect that 316 is stronger than 304 cannot be reflected at all. Therefore, consumers can make comprehensive judgments based on needs and cost-effectiveness when choosing products, and purchase appropriate products.