In our daily lives, many products are made from 304 stainless steel. For example, the water bottle we use often has a clear 304 mark at the bottom. How much do you know about 304 stainless steel?
What is 304 stainless steel?
304 stainless steel is a grade of stainless steel according to the American ASTM standards. It’s the most widely used stainless steel and heat-resistant steel.
304 stainless steel is equivalent to China’s 0Cr19Ni9 (0Cr18Ni9) stainless steel. It contains 19% chromium and 9% nickel, which are the defining elements for 304 stainless steel.
What are other equivalents of AISI 304?
X5CrNi18-10, EN 1.4301, DIN 1.4301, UNS S30400, BS 304S15, BS 304S16, BS 304S31, BS EN58E
What is Chemical composition of AISI 304 and What are the uses of these Chemical elements?
| ELEMENT | WEIGHT | USAGE |
| Iron | 66.74 – 71.24% (Balance) | It is the base element of 304, which contribute to basic mechanical properties and magnetic characteristics: |
| Chromium | 17.5 – 19.5% | It is the main alloy element and provide good corrosion resistance and oxidation resistance |
| Nickel | 8 – 10.5% | Another alloy element, It provides good ductility and toughness |
| Manganese | 2% | It enhances strength and toughness. |
| Silicon | 1% | It improves oxidation resistance and high-temperature resistance |
| Nitrogen | 0.11% | It improves strength and pitting corrosion resistance. |
| Carbon | 0.07% | It increases strength and hardness but decreases ductility and toughness. |
| Phosphorus | 0.05% | It increases strength and hardness but decreases ductility and toughness |
| Sulphur | 0.03% | It improves machinability but reduces hot working performance and corrosion resistance |
Which industries are 304 stainless steel used for?
Food Processing
Such as piping system, beverage equipment, storage tanks
Household Items
Such as kitchen appliances, sinks
Chemical Equipment
chemical processing equipment, reactors, and storage tanks
Medical Instruments
medical instruments, surgical tools, and implants
Construction Materials
handrails, windows, and decorative elements
What are the advantages of 304 stainless steel?
Excellent corrosion resistance
Due to its high chromium and nickel content, 304 stainless steel can form a stable passive film in various environments, preventing further oxidation and corrosion.
Excellent oxidation resistance
Due to its high chromium and nickel content, 304 stainless steel can maintain a stable oxide film at high temperatures, preventing oxidation and corrosion under high temperature conditions.
Excellent ductility and toughness
with its high nickel content, 304 stainless steel can maintain an austenitic structure, offering good toughness even at low temperatures. This allows for both cold and hot forming processes.
Excellent processing performance
With low levels of impurities such as carbon, sulfur, and phosphorus, 304 stainless steel can be easily machined through processes like cutting, welding, and bending, without prone to cracking or embrittlement.
Excellent surface finish
Thanks to its high chromium and nickel content, 304 stainless steel can achieve a bright surface finish, resistant to contamination and discoloration
Conclusion
304 is a stainless steel material with excellent overall performance. But it also has limits. When the products are used in seawater or high temperature environments, BT can provide other stainless steel like 316/316L/321 for your better choice based on the different applications.
FAQs about AISI 304 Stainless Steel
Is AISI 304 the same as SUS 304?
AISI 304, SS 304, SAE 304, and SUS 304 all refer to the same material but are labeled differently depending on the context in which they are cited.
SUS304, also known in the industry as 18/8 stainless steel, has a density of 7.93 g/cm³ and is a common material in everyday life.
AISI 304 is a type of stainless steel that meets the American 304 standard. It has excellent resistance to intergranular corrosion in oxidizing acids, making it widely used in industrial applications.
Is AISI 304 magnetic?
304 stainless steel is non-magnetic in its annealed condition. However, after cold working processes such as stamping, drawing, bending, or rolling, some of its austenitic structure can transform into martensite, resulting in a slight magnetic property.
How to calculate the weight of 304 plates?
To calculate the weight of a 304 stainless steel sheet, you first need to know its density, which is 7.93 g/cm³. The formula to calculate the weight of a 304 stainless steel sheet is:
weight (kg)=Thickness (mm)×Width (m)×Length (m)×Density (7.93 g/cm³)