Science, Tech, Math › Science Type 304 and 304L Stainless Steel Learn about the uses and properties of these two metals Share Flipboard Email Print Sigrid Gombert / Getty Images Science Chemistry Chemistry In Everyday Life Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate by Terence Bell Terence Bell wrote about commodities investing for The Balance, and has over 10 years experience in the rare earth and minor metal industries. Updated January 11, 2020 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% chromium. But not all stainless steels are the same. Stainless Steel Grading 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 categories in between. Each comes with distinct properties and falls into families including: austenitic: non-magneticferritic: magneticduplexmartensitic and precipitation hardening: high strength and good resistance to corrosion Here, we explain the difference between two common types found on the market — 304 and 304L. Type 304 Stainless Steel Type 304 is the most widely used austenitic stainless steel. It is also known as "18/8" stainless steel because of its composition, which includes 18% chromium and 8% 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, the heat treatment that softens metals. Common uses for type 304 stainless steel are found in the food industry. It's ideal for brewing, milk processing, and wine-making. It's also suitable 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. Type 304L Stainless Steel Type 304L stainless steel is an extra-low carbon version of the 304 steel alloy. The lower carbon content in 304L minimizes deleterious or harmful carbide precipitation as a result of welding. 304L can, therefore, be used "as welded" in severe corrosion environments, and it eliminates the need for annealing. This grade has slightly lower mechanical properties than the standard 304 grade, but is still widely used thanks to its versatility. Like Type 304 stainless steel, it's commonly used in beer-brewing and wine-making, but also for purposes beyond the food industry such as in chemical containers, mining, and construction. It is ideal for use in metal parts such as nuts and bolts that are exposed to salt water. 304 Stainless Physical Properties: Density: 8.03g/cm3Electrical 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 tensionMelting Range: 2550-2650°F (1399-1454°C) Type 304 and 304L Stainless Steel Composition: Element Type 304 (%) Type 304L (%) Carbon 0.08 max. 0.03 max. Manganese 2.00 max. 2.00 max. Phosphorus 0.045 max. 0.045 max. Sulfur 0.03 max. 0.03 max. Silicon 0.75 max. 0.75 max. Chromium 18.00-20.00 18.00-20.00 Nickel 8.00-10.50 8.00-12.00 Nitrogen 0.10 max. 0.10 max. Iron Balance Balance Source: AK Steel Product Data Sheet. 304/304L Stainless Steel Continue Reading Properties of Type 316 and 316L Stainless Steels What Is Type 201 Stainless Steel? The Properties and Applications of Ferritic Stainless Steel Different Steel Alloys Have Different Properties and Uses Compare 20 Grades of Knife Steel Key Properties and Effects of Common Steel Alloying Agents What Is Iron? Characteristics of and Uses for Austenitic Stainless Steel A Look at Nickel Metal: It's Properties, History, Production & Uses Properties, Composition and Production of Metal Alloys The History, Properties, Characteristics and Uses of Molybdenum Tungsten (Wolfram) Metal: Properties, Production, Applications & Alloys Properties of Monel 400, a Nickel-Copper Alloy That Resists Corrosion Learn How the Normalizing Process for Steel Makes It More Workable What Are Monel Alloys? How Are They Used? What Are the Physical Properties of Beryllium Copper?