Stainless steel is one of the world’s most important materials. Consisting of iron mixed with chromium, nickel, carbon and other elements, it’s known for its strong yet corrosion-resistant properties.
Pure iron is highly susceptible to corrosion. When exposed to oxygen, it will undergo a chemical reaction known as oxidation that converts the metal into iron oxide. Steel, however, often contains additional elements to protect against oxidation and enhance their properties. 300 and 303 stainless steel, for example, are specific types of steel with added elements. To learn more about 300 and 303 stainless steel, keep reading.
What Is 300 Stainless Steel?
300 stainless steel is a subfamily of austenitic stainless steels that features a high concentration of chromium and nickel as alloys. It consists of at least 18% chromium and 8% nickel. 300 stainless steel still consists primarily of iron, but it has a high concentration of these other elements as well. The presence of chromium and nickel enhances its corrosion-resistant properties.
What Is 303 Stainless Steel?
303 stainless steel is a specific type of austenitic stainless in the 300 subfamily. It’s essentially a modified version of 304 stainless steel, with sulfur or selenium. 303 stainless steel contains many of the same elements as its 300 counterpart, but it also features sulfur or selenium for improved machinability.
Differences Between 300 and 303 Stainless Steel
There are several key differences between 300 and 303 stainless steel, one of which is corrosion resistance. While they are both classified as stainless steel, 300 stainless steel offers a higher level of protection against oxidation and corrosion. As previously mentioned, 300 stainless steel has at least 18% chromium. This chromium creates a protective shell-like barrier over the surface of the steel, thereby preventing oxygen from reaching the inner iron.
303 stainless steel offers some level of protection against oxidation and corrosion, but not as much as 300 stainless steel. 303 stainless steel has sulfur or selenium added to it, which makes it more susceptible to oxidation and corrosion.
303 stainless steel, on the other hand, offers better machinability. It can be cut and machined more easily than 300 stainless steel. The sulfur makes it easier to cut and shape, reducing wear on tools and improving overall production efficiency.
Both 300 and 303 stainless steel are strong and durable. However, 303 stainless steel tends to have slightly lower mechanical strength. Despite this, the tradeoff for easier machinability often outweighs the marginal loss in strength for many applications.