Stainless steel is a durable and very adaptable material. It delivers exceptional durability, strength, and corrosion resistance. Because of this, it is a common option for many industrial applications. But with so many options available, how can you choose the best stainless steel for your specific requirements? To assist you in choosing the best form of stainless steel for you, let's examine two of the most popular types: duplex and SS 316.

Duplex Stainless Steel

Austenitic and ferritic steel are combined to create duplex stainless steel (DSS), which is stronger than either type by itself. In addition to 18–26% chromium, 3-5% nickel, 2-4% molybdenum, 0.04-0.10% nitrogen, 0.1–1% manganese, 1.3–3% silicon, and 0.08%–0.20% carbon, DSS also contains some other elements in trace amounts. When compared to other steels, DSS has better corrosion resistance due to its higher chromium content and nitrogen content. Ferritic grades of stainless steel, like SS430 or SS440C, also have better ductility and weldability.

Stainless Steel 316

SS 316 is an austenitic grade with trace levels of carbon (less than 0.03%), 16–18% chromium, 10–14% nickel, and 2-3% molybdenum. This grade has outstanding corrosion resistance despite having less chromium and nitrogen than DSS because of its high concentration of nickel and molybdenum, two elements renowned for their ability to withstand corrosion in challenging situations. SS 316 stainless steel has a larger nickel content than other austenitic grades like SS304 or SS310, therefore it is more formable and weldable while still maintaining the strength and durability advantages of austenitic grades.

Chemical Composition

The chemical makeup of duplex stainless steel and 316 stainless steel is one of their main distinctions. In comparison to 316 stainless steel, duplex stainless steel has a higher content of chromium, molybdenum, and nickel. Due to this, duplex stainless steel is more corrosion-resistant than 316 stainless steel.

Mechanical Properties

Additionally, compared to 316 stainless steel, duplex stainless steel exhibits better mechanical qualities. This entails improved toughness, stress corrosion cracking resistance, and strength.

Weldability

316 stainless steel and duplex stainless steel are both very weldable. Due to its reduced carbon content, duplex stainless steel is, however, a little bit simpler to weld than 316 stainless steel.