What Is The Difference Between Stainless Steel 304 And Stainless Steel 316?

What is the difference between stainless steel 304 and stainless steel 316

1.Chemical composition:
The chemical composition of stainless steel 304 includes 18-20% chromium (Cr) and 8-10.5% nickel (Ni), as well as small amounts of carbon (C), (Mn) and other elements. In addition to 18-20% chromium and 8-10.5% nickel, stainless steel 316 also adds 2-3% platinum (Mo). The addition of titanium can improve the corrosion resistance of stainless steel, especially in high temperatures and corrosive media.
 

2. The structure determines the properties. Due to the difference in composition, the properties of 304 stainless steel and 316 stainless steel are different:
Through the comparison of Figure 1 and Figure 2, it is found that the difference in its composition is mainly due to the difference in carbon, chromium, nickel, and silver content. The different contents of these elements lead to different properties, such as:
Chromium (Cr): Increases hardness, strength, toughness and wear resistance; improves oxidation resistance and corrosion resistance, reduces plasticity and toughness Nickel (Ni): Improves strength, maintains good toughness and plasticity, and improves corrosion resistance , rust-proof and heat-resistant at high temperatures. (Mo): Enhance strength, improve impact resistance and heat resistance, improve hardenability and thermal strength properties, maintain sufficient creep resistance at high temperatures; inhibit brittleness caused by quenching.

Both 304 series and 316 series stainless steel are austenitic stainless steel, which have the characteristics of good processing performance, corrosion resistance and rust resistance. Compared with the two, 316 has stronger corrosion resistance and heat resistance than 304. The main reason is that Just some differences in their chemical composition.
(1) The 316 series adds the (Mo) element. In addition to enhancing strength and heat resistance, (Mo) can also improve the corrosion resistance in the atmosphere, greatly improving the corrosion resistance of the 316 series stainless steel.
(2) The 316 series also contains 2%-3% more nickel (Ni), which improves its durability, mechanical properties, corrosion resistance, and oxidation resistance.

3. Different properties make 304 stainless steel and 316 stainless steel have different uses.
In indoor environments and general outdoor environments, choosing 304 stainless steel fasteners can resist natural corrosion and other problems. However, if it is seawater equipment, chemical, fuel and other production equipment, industrial environments, facilities in coastal areas, etc., it is necessary to Choose 316 or 316L stainless steel fasteners with stronger performance