Stainless Steel Grade Comparison Table
A comparison of stainless steel grades is an important step in helping to ensure that you select the best stainless steel grade for your application. In order to determine the right grade of stainless steel for your needs, it is necessary to understand the different characteristics of the common grades available today. In this comparison table, we have grouped together the various grades of stainless steel based on their differences so that you can easily compare the differences between grades.
Austenitic Stainless Steel Grades
The most common types of stainless steel are austenitic grades, which contain high levels of chromium and nickel and are the highly corrosion resistant. The austenitic grades are classified into three main groups, which are 200-series, 300-series and 400-series. The 200-series grades are the most widely used and commonly used, and these grades offer excellent resistance to general and acidic corrosion. The 300-series grades provide higher levels of chromium and nickel and provide better resistance to corrosion under more extreme conditions. Finally, the 400-series grades are generally used for specialty applications.
Ferritic Stainless Steel Grades
Ferritic grades of stainless steel usually contain less than 0.12% carbon and the corrosion resistance is less than that of the austenitic grades. However, ferritic grades are often chosen for applications in areas where good formability and weldability are desired. Ferritic grades of stainless steel are typically used in automotive exhaust systems, gas turbines, and heat exchangers.
Martensitic Stainless Steel Grades
Martensitic stainless steel grades are similar to ferritic stainless steel grades, but have a higher content of carbon. This higher content of carbon allows these grades to be hardened and tempered, which makes them ideal for applications that require a higher level of strength. Martensitic grades are typically used in blades, turbine blades, and springs.
Duplex Stainless Steel Grades
Duplex stainless steel grades are composed of both ferritic and austenitic components, and this combination offers a higher level of corrosion resistance than either component on its own. These grades are also typically stronger than single component grades and are used for applications such as offshore platform components and process equipment.
Precipitation-Hardening Stainless Steel Grades
Precipitation-hardening grades are designed to be heat treated, which causes small amounts of alloy elements to be dissolved from the structure and then “precipitated” out of solution, which hardens the material. These grades are ideal for applications that require both a high level of corrosion resistance and a high strength/toughness combination.
Summary
When selecting stainless steel, it’s important to consider the various grades of steel and their various characteristics. Austenitic grades provide good corrosion resistance and are the most commonly used grades. Ferritic and martensitic grades are often chosen for applications where good formability and weldability are desired. Duplex grades offer a high level of corrosion resistance and are often used for offshore components and process equipment. Finally, precipitation-hardening grades are used for applications that require both a high level of corrosion resistance and strength/toughness. We hope that this comparison table has been helpful in helping you to better understand the difference between stainless steel grades.
