What quality is 201 stainless steel?
As we all know, SAE 304 stainless steel is the most versatile stainless steel used in various industries, apart from its "close cousin" SAE 316 stainless steel. However, the high nickel content in SAE 304 alloy makes this stainless steel type quite expensive, so engineers sometimes resort to a more affordable alternative: SAE 201 stainless steel.
In this guide, we'll discuss Stainless Steel 201 vs. Stainless Steel 304, their differences, similarities, and their applications.
What is the difference between SAE 201 and SAE 304 stainless steel?
In addition to the chemical composition differences that we will discuss later, there are some almost imperceptible visual differences between these two stainless steels. That said, SAE 201 appears slightly darker compared to SAE 304 due to the generally lower chromium content and higher manganese content.
However, as mentioned above, these differences are barely noticeable, and you would have to place the two stainless steel materials next to each other for them to become noticeable.
chemical composition
Both grades of stainless steel have relatively high chromium and nickel content. However, they belong to a completely different alloy group, and that's what makes them different. SAE 304 is an austenitic stainless steel containing 18% to 20% chromium, 0.08% carbon, and 8%-10% nickel. This type of steel is a chromium-nickel alloy.
However, SAE 201 stainless steel belongs to the chromium-manganese-nickel group, which means that the manganese content is relatively high and the nickel content is relatively low. SAE 201 is an austenitic stainless steel with a relatively high carbon content of 0.15% and a relatively low nickel content of 3.5% to 5.5%. It contains approximately 16-18% chromium and 5.5% to 7.5% manganese.
Corrosion resistance
Both SAE 304 and SAE 201 obtain their corrosion resistance through their chromium and nickel content. However, SAE 304 has higher percentages of both alloying elements within the allowable range, which provides the alloy with excellent corrosion resistance.
Unfortunately, SAE 201 has fewer of these alloying elements, which makes it less corrosion resistant than SAE 304. The latter is mainly used in hygienic applications such as food-grade containers and stainless steel water bottles due to its good corrosion resistance.
However, some insulated water bottle manufacturers use SAE 201 in their stainless steel products, which is an inadequate application and possibly even a dangerous misuse of the material.
physical properties
SAE 201 stainless steel is relatively stiffer than SAE 304, while SAE 304 has much better mechanical properties and fatigue resistance than SAE 201. However, the appeal of SAE 201 lies in its affordable price tag, good performance in cold weather and indoor applications such as door handles or workpiece holding elements such as jigs and fixtures.
