What exactly are the differences between 201 and 904L stainless steel?
Stainless steel, as an important metallic material, is widely used in multiple fields such as construction, industry, medical care, and catering. Among the stainless steel family, different models such as 201, 304, 316L, and 904L often leave people dazzled. So, what exactly are the differences among these stainless steels? Today, let's take a detailed look.
Model performance comparison
|
Model
|
Corrosion resistance
|
Strength
|
Cost
|
Processability
|
Application scenarios
|
|
201
|
Weak
|
High
|
Low
|
General
|
Decorative materials, low-end tableware
|
|
304
|
Excellent
|
Medium
|
Medium
|
Excellent
|
Kitchen utensils, food equipment
|
|
316
|
Excellent
|
Medium
|
High
|
Excellent
|
Medical equipment, marine equipment
|
|
430
|
Weak
|
Medium
|
Low
|
Good
|
Household appliance housing, decorative materials
|
|
2205
|
Excellent
|
High
|
High
|
General
|
Petrochemical, high-pressure pipelines
|
|
904L
|
Excellent
|
Medium
|
Extremely high
|
General
|
Chemical equipment, high-end watches
|
1. Basic concepts of stainless steel
Stainless steel is a kind of chromium-containing alloy steel, and its main feature is strong corrosion resistance. According to its chemical composition and microstructure, stainless steel can be classified into several major categories, such as austenitic, ferritic, martensitic and duplex stainless steel. Among them, 201, 304, 316L and 904L all belong to austenitic stainless steels. Their corrosion resistance and mechanical properties mainly depend on the content of alloying elements in them.
2.201 Stainless steel
Features:
201 stainless steel is an austenitic stainless steel with a relatively high manganese content. Compared with other models, it has a lower nickel content and thus a lower cost. It can replace 304 stainless steel to a certain extent, but its corrosion resistance is relatively weak.
Advantages:
The price is low and the cost performance is relatively high.
It has a certain anti-rust ability and is suitable for dry environments.
Disadvantage:
It has poor corrosion resistance, especially being prone to rust in damp or acidic environments.
It has relatively low strength and is not suitable for occasions with high strength requirements.
Application field:
It is mainly used for low-end tableware, kitchenware, decorative materials, etc.
3.304 Stainless steel
Features:
304 is the most common type of stainless steel, with a relatively high nickel content (generally above 8%), thus it has excellent corrosion resistance and mechanical properties.
Advantages:
It has excellent corrosion resistance and can maintain good anti-rust ability in most environments.
It has strong plasticity and is easy to be processed into various shapes.
It has excellent high-temperature resistance.
Disadvantage:
The cost is relatively high.
It may be corroded in strong acid and strong alkali environments.
Application field:
It is widely applied in fields such as food processing equipment, medical devices, architectural decoration, and chemical containers.
4.316L stainless steel
Features:
316L is a low-carbon version improved on the basis of 304. Its most prominent feature is the addition of 2% to 3% molybdenum, which significantly enhances its corrosion resistance, especially in a chloride ion environment, it has a stronger resistance to pitting corrosion.
Advantages:
It has excellent corrosion resistance, especially performing well in seawater or saline environments.
The low carbon content makes its welding performance better and less prone to intergranular corrosion.
It has excellent mechanical properties and is suitable for occasions with high-intensity demands.
Disadvantage:
The cost is relatively high.
For some extreme environments, higher-grade stainless steel may still be required.
Application field:
It is commonly used in Marine equipment, chemical equipment, medical devices and high-end tableware, etc.
Features:
904L is a super austenitic stainless steel with extremely high nickel and molybdenum content, thus possessing extremely strong corrosion resistance. It is usually used in extremely corrosive environments, such as those with strong acids, strong alkalis or high salt concentrations.
Advantages:
It has outstanding corrosion resistance and can remain stable even in strongly acidic environments.
It has extremely strong resistance to pitting corrosion and is suitable for long-term exposure to chloride ions.
High strength and good ductility.
Disadvantage:
It is very expensive and has the highest price among all models.
The processing is rather difficult and has high requirements for equipment and technology.
Application field:
It is widely used in fields such as chemical equipment, the pharmaceutical industry, high-end watch cases, and Marine engineering.
