There are numerous stainless steel grades to choose from—such as grade 304 stainless steel, grade 430 stainless steel, or grade 420 stainless steel (which are, in order, examples of austenitic, ferritic, and martensitic stainless steel alloys). Considering that there are thousands of types of stainless steel, how can you choose the right alloy to meet your needs?
Here are a few tips for choosing between different stainless steel grades that
Sorting Types of Stainless Steel Based on Process Temperatures
While most varieties of stainless steel have a fairly high melting point, this point varies from one type of stainless steel to the next. Additionally, some stainless steel grades better resist scaling and oxidation than other varieties at high temperatures.
So, sorting your stainless steel choices based on their maximum use temperature and/or melting point makes for an easy pass/fail test for your manufacturing process. If the steel can’t take the temperatures used in your process, then you should skip it. This is most often useful for heat treatment or temperature-based sterilization processes, as these heat-intensive processes are more likely to push the limits of a stainless steel alloy’s temperature tolerance.
Check the Corrosion Resistance of Each Stainless Steel Grade You Consider
Part of the reason, not every grade of stainless steel resists the same corrosives. Some types of stainless steel are better at resisting certain types of acidic compounds, some are less susceptible to pitting from exposure to salt, and some are resistant to a wide variety of corrosive compounds.
It can be difficult to generalize about the corrosion resistance of different types of stainless steel. However, austenitic stainless steels, such as grade 304 or 316 stainless steel, tend to have better overall corrosion resistance than other types of stainless steel. This is because austenitic stainless steels have a higher chromium content, which helps improve general corrosion resistance (though it doesn’t always guarantee better resistance to every corrosive).
It’s important to check with a steel manufacturer to get their specifications on what corrosives their steel alloys can resist and compare that to the specific corrosives that are used in your manufacturing process.
