Stainless steel takes its name from its ability to resist rusting thanks to the interaction between its alloying components and the environment to which they're exposed. Numerous types of stainless steel serve a variety of purposes and many overlap. All stainless steels are comprised of at least 10 percent chromium. But not all stainless steels are the same. In fact, there are varying degrees of the metal — something many of us don't readily know.
Each type of stainless steel is graded, usually in a series. These series classify the different types of stainless from 200 to 600, with many different categories in between. Each comes with different properties and fall into different families including austenitic (non-magnetic), ferritic (magnetic), duplex, and martensitic and precipitation hardening (high strength and good resistance to corrosion) stainless.
Type 304 Stainless Steel
Type 304 is the most widely used austenitic (non-magnetic) stainless steel. It is also known as "18/8" stainless steel because of its composition, which includes 18 percent chromium and 8 percent nickel. Type 304 stainless steel has good forming and welding properties as well as strong corrosion resistance and strength.
This kind of stainless steel also has good drawability. It can be formed into a variety of shapes and, in contrast to type 302 stainless, can be used without annealing. Common uses for type 304 stainless steel are found in the food industry. It's ideal for brewing, milk processing and wine-making, as well as for pipelines, yeast pans, fermentation vats and storage tanks.
Type 304 grade stainless steel is also found in sinks, tabletops, coffee pots, refrigerators, stoves, utensils and other cooking appliances. It can withstand corrosion that can be caused by various chemicals found in fruits, meat and milk. Other areas of use include architecture, chemical containers, heat exchangers, mining equipment, as well as marine nuts, bolts and screws. Type 304 is also used in mining and water filtration systems and in the dyeing industry.
304 Stainless Physical Properties:
Electrical resistivity: 72 microhm-cm (20C)
Specific Heat: 500 J/kg °K (0-100°C)
Thermal conductivity: 16.3 W/m-k (100°C)
Modulus of Elasticity (MPa): 193 x 103 in tension
Melting Range: 2550-2650°F (1399-1454°C)
Type 304 Stainless Steel Composition:
Type 304 (%)