Stainless steels are used in many metal applications due to their strength, corrosion resistance, and cost-effectiveness. There are Ferritic, austenitic, and duplex stainless steel. 304 and 316 steel sheets are austenitic SS. They contain both 18% chromium and 8% nickel in the composition. Material 316 contains molybdenum in its composition. 4% molybdenum allows material 316 to have high corrosion resistance against chloride ions. Both materials contain carbon, iron, manganese, phosphorus, sulfur, and silicon.
As part of the five families of stainless steel, 304 stainless steel and 316 stainless steel are austenitic grades that contain high levels of chromium and nickel. This has the following impact:
- Chromium – Enhances tensile strength, hardness, hardenability, toughness wear and abrasion resistance, corrosion resistance and resistance to scaling at elevated temperatures.
- Nickel – Enhances strength and hardness without sacrificing ductility and toughness.
But the addition of alloy elements like molybdenum can make subtle, but important, differences.
- Molybdenum – Enhances strength, hardness, hardenability, and toughness as well as creep resistance, and strength at elevated temperatures.
What is 304 Stainless Steel and Where Is It Used?
As the most widely used of all stainless steel, 304 stainless steel pipes is most notably present in industrial applications and kitchen equipment. It is a very heat resistant grade and offers good corrosion resistance to many corrosive chemicals as well as industrial atmospheres. With excellent formability, 304 stainless steel can be readily welded by all common methods.
304L stainless steel is an extra low carbon variation that avoids harmful carbide precipitation due to welding. This variation offers the same corrosion resistance as 304 stainless steel, but with slightly lower mechanical properties.
What is 316 Stainless Steel and Where Is It Used?
When it comes to 316 stainless steel pipes, you can expect better corrosion and pitting resistance to chlorides than 304 stainless steel and higher levels of strength at elevated temperatures. This is due in part to the addition of molybdenum. This is what makes it an ideal grade for such applications as pumps, valves, textile and chemical equipment, pulp & paper, and marine applications.
316L stainless steel is the extra-low carbon version of 316 stainless steel that helps avoid carbide precipitation due to welding.
So, What’s the Difference Between 304 Stainless Steel and 316 Stainless Steel?
When it comes to 304 stainless steel vs. 316 stainless steel, while both are good for corrosion resistance, strength, welding, and heat resistance, 316 stainless steel gets the slight edge in all these categories due to variation in alloying elements.