Which is better SUS304 or sus 316?
Gnee Steel
Which is better SUS304 or sus 316
SUS304 is suitable for general purposes and offers good value for money; while SUS316, due to the addition of molybdenum, is more corrosion-resistant and therefore more suitable for harsh corrosive environments, such as marine or chemical environments, but it is also more expensive. SUS304 is a common material for kitchen equipment, while SUS316 performs exceptionally well in coastal areas/chemical processing fields, offering better resistance to chlorides, salts, and extreme temperatures.
Gnee steel
Is SUS304 stainless steel good quality?
304 stainless steel possesses excellent resistance to atmospheric corrosion, water, and various chemical substances. Furthermore, due to its ease of processing, 304 stainless steel is a commonly used material for metal castings and is widely applied in areas such as pump and valve components, food processing equipment, bearings, heat exchangers, and pressure vessels.
SUS304 and SUS316 are both austenitic stainless steel grades. Their main difference lies in their composition. SUS304 contains chromium, nickel, and manganese, while SUS316 contains a higher content of molybdenum, which improves its corrosion resistance. Other significant differences include the percentage of carbon content and the presence or absence of nitrogen.
Comparison of the properties of SUS304 and SUS316
The characteristics of each are briefly summarized in the table below. Please note that these are the relative characteristics of SUS304 and SUS316.
|
Corrosion Resistance |
Magnetic |
Processability |
Price |
|
|
SUS304 |
Inferior |
None※ |
Excellent |
Cheap |
|
SUS316 |
Excellent |
None |
Inferior |
Expensive |
Comparison of Physical Properties of SUS304 and SUS316
|
Chemical composition |
Carbon (C) |
Silicon (Si) |
Manganese (Mn) |
Phosphorus (P) |
Sulfur (S) |
Nickel (Ni) |
Chromium (Cr) |
Mo |
|
SUS304 |
Less than 0.08 |
Less than 1.00 |
Less than 2.00 |
Less than 0.045 |
Less than 0.030 |
8.0-10.5 |
18.0-20.0 |
– |
|
SUS316 |
Less than 0.09 |
Less than |
Less than 2.01 |
Less than 0.045 |
Less than 0.030 |
10.0-14.0 |
16.0-18.0 |
2.0-3.0 |
|
Physical properties |
Density (kg/ m3 ) |
Modulus of elasticity (Gpa) |
Specific electrical resistivity (room temperature) μΩ cm |
Specific heat ((0-100℃) KJ/kg ・K) |
Thermal conductivity ((100℃)W/m・K) |
Thermal expansion coefficient (0~ |
|
SUS304 |
7930 |
193 |
72 |
0.5 |
16.3 |
17.3 |
|
SUS316 |
7980 |
193 |
74 |
0.5 |
16.3 |
15.9 |
|
Mechanical properties |
Strength (N/m㎡) |
Tensile strength (N/m㎡) |
Stretch (%) |
Aperture (%) |
HB |
HRB |
HV |
|
SUS304 |
More than 205 |
More than 520 |
More than 40 |
More than 60 |
Less than 187 |
Less than 90 |
Less than 200 |
|
SUS316 |
More than 205 |
More than 520 |
More than 40 |
More than 60 |
Less than 187 |
Less than 90 |
Less than 200 |
Characteristics of SUS304
SUS304 (AISI 304) is a typical austenitic stainless steel, accounting for 60% of total stainless steel production. It is widely used, easily processed at room temperature, and commonly used in stamping, drawing (cold working), and welding.
Application areas include:
Household items
Building interior and exterior decoration
Factory equipment
Due to its 18% chromium and 8% nickel content, it is sometimes referred to as 18Cr-8Ni. Compared to other stainless steels, its lower chromium and nickel content makes it more economical. Although it is inherently non-magnetic, during processing, some of its structure may transform into martensite, resulting in slight magnetism.
Characteristics of SUS316
SUS316 (AISI 316) is a non-magnetic stainless steel. Due to the addition of molybdenum (Mo), its corrosion resistance and pitting resistance are superior to SUS304. The reason for its better corrosion resistance is as follows:
Stainless steel resists rust because a thin oxide passivation film forms on its surface.
Chromium helps to form this self-repairing passivation film, but in chloride-rich environments (such as seawater), the stability of the passivation film is reduced.
The addition of molybdenum enhances the self-repairing ability of the passivation film, giving SUS316 stronger corrosion resistance, especially against pitting corrosion (localized rust spots).
SUS316 contains more molybdenum and nickel than SUS304, which improves its corrosion resistance but also increases the cost. It is suitable for environments with a high risk of corrosion, such as exposure to seawater, coastal air, or sea breezes. In more severe environments, stainless steel with higher corrosion resistance than SUS316 may be required.
Gnee Steel also supplies custom SUS 304 stainless steel products in various sizes and specifications. Please send us your drawings for a quote!
