How to Pick the Right Stainless Steel Grade
Stainless steel is arguably one of the greatest inventions in human history. With millions of applications spanning across every major industry, the production of the metal alloy continues to rise globally. In 2019, worldwide steel production was approximated at 52.2 million metric tons, more than doubling from a decade before.
Stainless steel comes in a variety of grades, such as 302 stainless steel. With over 3500 grades to choose from, it can be challenging for fabricators to find the right grade. Here are five tips to guide you during the selection process.
1. Operating Environment
The metal alloy or combined metals are forged from a combination of steel and other metals such as chromium and nickel. Steel’s anti-corrosive properties and versatility make it vital in countless applications in industries such as construction, automobiles, food and beverage, medical, and chemical processing, to name a few.
You need to find a steel grade that will uphold the best in a given environment. Think about the conditions that the steel product will face. High temperatures, varying pH levels, stress, and corrosion may impact the functionality of your steel. Austenitic grades such as 302 stainless steel, 304, and 316 series retain their strength, corrosion resistance, and toughness properties on a broad temperature range.
2. Mechanical Qualities
Next, you may need to give importance to mechanical qualities, such as strength, ductility, and toughness. Strength refers to the stress that a metal can withstand before deforming or fracturing. Ductility relates to the ability of a metal to have its shape changed. Toughness is the ability to deform and absorb energy before a metal fracture.
Stainless steel contains 10-30% chromium that aids in corrosion prevention. Nickel addition in austenitic grades like 302 stainless provides the highest toughness and ductility. Martensitic steels, like grade 440C, provide the best strength.
3. Corrosion Resistance
While stainless steel gets a good rap for being corrosion resistant, it varies greatly among the different grades. Austenitic grades such as 316, 304, and 302 stainless steel are among the most sought after for corrosion resistance due to high levels of chromium. Ferritic steel grades and martensitic are more affordable but will have fewer percentages of nickel and chromium.
If the application of the stainless steel casts requires good formability, it would be wise to avoid martensitic grades. These grades often tend to be brittle and not formable. Austenitic grades such as 304 stainless steel or 302 stainless steel would be an excellent choice. Ferritic grades such as 430 can also work.
5. Material Cost and Availability
You may need to find out the common applications of the different grades of steel to help you choose the right one for your project. Alloy 302 stainless steel is commonly used in stamping and spinning. Ferritic grade 409 is majorly in automotive exhaust systems, while austenitic 316L is for chemical applications that require welding. Austenitic steel grades are usually the most expensive upfront. Carefully examine the cost, needs, and availability of the thin sheet metal before settling for one.
Stainless steel is useful for a wide range of applications due to the versatility in steel grades. Finding the right steel to use is vital in reducing maintenance, downtime, and replacement costs. Thin Metal Sales provides the highest quality of custom premium grade stainless steel sheets. Contact us now to discuss your stainless steel grade needs.