When choosing between hygienic stainless steel 304 and 316, it’s important to understand their differences. Let’s explore the distinctions with Hoa Giang in the following article.
What is Stainless Steel 304?
Chemical Ingredients
Stainless steel 304, also known as SUS 304, is the most common and widely used type of stainless steel. It belongs to the Austenitic group of stainless steels. The primary components of stainless steel 304 are Chromium and Nickel, which form a protective oxide layer on the surface, providing excellent corrosion resistance. The specific ingredients includes:
- 17.5% – 20% Chromium
- 8% – 11% Nickel
- 0.03% – 0.08% Carbon
- 0.03% Sulfur
- 1% Silicon
- 0.45% Phosphorus
- 1% – 2% Manganese
Stainless steel 304 can be further categorized into two main types:
- Stainless steel 304L: This type has a lower carbon content, making it ideal for applications that require welding, as it reduces the risk of intergranular corrosion.
- Stainless steel 304H: A variant of 304 with a higher carbon content compared to 304 and 304L. This higher carbon content gives 304H superior high-temperature performance, making it suitable for high-temperature applications.
Key Characteristics
Stainless steel 304 possesses several key characteristics:
- High strength, excellent corrosion resistance, and colorfastness. It can withstand external forces and is difficult to deform. These properties make stainless steel 304 the most widely used type in daily life.
- Heat resistance up to 870 – 925°C in continuous use. Even at higher temperatures, it can withstand short-term exposure.
- Excellent formability, allowing for easy bending and thinning. This makes stainless steel 304 ideal for manufacturing various products, components, and parts.
- Smooth, shiny surface that is easy to clean and has a high aesthetic appeal.
Common Applications
Thanks to its outstanding properties, hygienic stainless steel 304 finds extensive use in various industries and daily life:
- Food industry: It is used for food and dairy storage tanks, blenders, mixers, presses, and kitchen utensils.
- Medical industry: It is used in the production of medical equipment and instruments that require high cleanliness and resistance to chemicals and saline solutions.
- Manufacturing: It is used to manufacture components and accessories for machinery and equipment.
- Construction: It is used for clean water piping and internal piping systems in buildings.
What is Stainless Steel 316?
Chemical Ingredients
Stainless steel 316, also known as SUS 316, is another austenitic stainless steel. Like stainless steel 304, its primary components are chromium and nickel. However, what sets stainless steel 316 apart is its significant molybdenum content, which provides superior corrosion resistance compared to other stainless steel grades. The specific ingredients includes:
- 16% Chromium
- 11% Nickel
- 2% Molybdenum
- 0.03% – 0.08% Carbon
- 0.03% Sulfur
- 1% Silicon
- 0.45% Phosphorus
- 1% – 2% Manganese
Key Characteristics
Stainless steel 316 is often referred to as the “material of the sea” due to its exceptional corrosion resistance. The presence of molybdenum in its composition provides outstanding resistance to corrosion, particularly in harsh environments such as chloride-containing solutions (seawater), acids, and alkalis. Stainless steel 316 also exhibits excellent corrosion resistance in normal temperature water environments. This type of stainless steel can withstand temperatures up to 500°C.
Common Applications
Thanks to its exceptional corrosion resistance, hygienic stainless steel 316 is widely used in industries and manufacturing processes that involve exposure to chemicals and salts:
- Food processing: Used in food and beverage processing equipment, such as storage tanks and carbonated beverage piping.
- Oil and gas industry: Used in equipment and pipelines in corrosive and high-temperature environments.
- Chemical processing: Used in equipment that comes into contact with corrosive chemicals.
- Medical industry: Used in surgical instruments, medical equipment, and biomedical implants that are exposed to chemicals and salts.
- Marine industry: Used in the production of ship components that are in direct contact with seawater.
Stainless Steel 304 and 316: Key Differences
In the previous sections, we have provided an overview and highlighted the key characteristics of stainless steel 304 and 316. In this section, Hoa Giang will present a comparison table to summarize the main similarities and differences between hygienic stainless steel 304 and 316.
| Features |
SUS 304 |
SUS 316 |
| Similarities | Both stainless steel grades are austenitic and share similar characteristics. These include:
|
|
| Chemical Ingredients |
|
|
| Expansion (0-538 °C) | 18.4 μm/m/°C | 17.5 μm/m/°C |
| Hardness |
|
|
| Weldability | Good – thanks to high Chromium and Nickel content | Better than 304 – thanks to the addition of Molybdenum in the composition, the weld can withstand high temperatures |
| Malleability | Easy to thin, bend, create small details | More difficult to roll than 304, requires high heat, mainly used to create large parts |
| Corrosion resistance | Good but still lower than 316, surface still pitted | Better than 304, thanks to Molybdenum it does not have surface pitting |
| Resistance to corrosion in salt (chloride) | Lower than 316, rusts over time | Up to about 1000 mg/L chloride at ambient temperature |
| Price
(VND/kg) |
54.000 – 68.000 | 65.000 – 88.000 |
| Applications | Widely used in the manufacture of items and components in the production of food, beverages, medicine, etc. | Used more in specific industries such as chemicals, pipes for producing carbonated soft drinks, ship components and accessories, marine construction, medical equipment exposed to chemicals,… |
Both stainless steel 304 and 316 are austenitic stainless steels with similar physical and chemical properties. However, the most significant difference between the two is their resistance to chloride ion corrosion (such as in seawater). This superior corrosion resistance of stainless steel 316 is attributed to the presence of molybdenum in its composition.
⇒ Read more about Sanitary and Industrial Stainless Steel: Distinction
Stainless Steel 304 and 316, Which One Is Better?
Deciding between stainless steel 304 and 316 can be challenging due to their overlapping properties. Both grades offer unique advantages and disadvantages. Here are some main factors to consider when making your decision:
Environment: For applications in harsh environments with high levels of acids, chlorides, or chemicals, stainless steel 316 is highly recommended due to its superior corrosion resistance.
Cost: If your application is in a non-corrosive environment and cost is a primary concern, stainless steel 304 is a more economical option.
Longevity: For long-term applications, stainless steel 316 is the better choice due to its superior corrosion resistance, which can extend its lifespan.
Industry-specific requirements:
- For food, beverage, pharmaceutical, and semiconductor industries, stainless steel 304 is often sufficient.
- For chemical processing and marine applications, stainless steel 316 is preferred due to its higher corrosion resistance.
Conclusion on Stainless steel 304 and 316
In conclusion, both stainless steel 304 and 316 are versatile materials with their own unique strengths. While stainless steel 304 is a cost-effective option for many applications, stainless steel 316 offers superior corrosion resistance, making it ideal for harsh environments. The optimal choice depends on factors such as the specific application, budget constraints, and industry standards. For demanding applications, stainless steel 316 is often the preferred choice. We hope this comparison has provided valuable insights to help you make an informed decision. If you need further assistance, please contact our team.
HOA GIANG STAINLESS STEEL GROUP
Address: No. 19 Bach Dang, Ward 2, Tan Binh District, Ho Chi Minh City
Phone: (028) 38485518~9
Email: sales.visinh@inoxhoagiang.com
Website: www.inoxhoagiang.vn – www.inoxhg.vn – www.hwayangvn.com