Which is better SUS304 or SUS316?

For engineers and procurement specialists, choosing the right stainless steel is crucial. Among the most common grades are SUS304 and SUS316, both austenitic stainless steels-but they have key differences in corrosion resistance, cost, and applications.

This guide helps buyers make an informed decision, featuring product data, mechanical properties, pricing, FAQs, and market insights.

 

What is SUS304 Stainless Steel?
SUS304 is the Japanese designation for stainless steel, equivalent to the American 304 stainless steel, and is classified as 06Cr19Ni10 in the Chinese national standard. It belongs to the 18-8 austenitic stainless steel family and is named for its approximately 18% chromium and 8% nickel content. Due to its excellent corrosion resistance, high-temperature resistance, good mechanical properties, and machinability, SUS304 is widely used in construction, food processing, medical equipment, and chemical equipment industries.

 

What is SUS316 stainless steel material?

SUS316 is an austenitic stainless steel with added molybdenum, giving it superior corrosion resistance compared to SUS304, especially in chloride environments (such as seawater). It possesses good plasticity, toughness, cold workability, and weldability, and is commonly used in the manufacture of corrosion-resistant equipment and products, but its cost is also higher than that of 304 stainless steel.

 

SUS304 vs SUS316 Stainless Steel:Chemical Composition

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

 

SUS304 vs SUS316 Stainless Steel:Mechanical Properties

Property	SUS304	SUS316
Tensile Strength	520 MPa	515 MPa
Yield Strength	215 MPa	205 MPa
Elongation	40%	40%
Hardness	170 HB	150–190 HB
Max Service Temperature	870°C	925°C
Density	7.93 g/cm³	8.0 g/cm³

 

SUS304 vs SUS316 Stainless Steel:Physical properties

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

 

Which is better, SUS304 or SUS316?
SUS316 contains more molybdenum and nickel than SUS304, which boosts resistance but increases cost. It is recommended for environments exposed to seawater, coastal air, or sea breezes, where corrosion risk is high. In harsher environments, stainless steels with even higher resistance than SUS316 may be required.

 

SUS304 vs. SUS316 stianless steel: Corrosion Resistance

SUS316 exhibits significantly superior corrosion resistance compared to SUS304, particularly when exposed to chloride and acidic environments. This is because SUS316 contains approximately 2% molybdenum, enhancing its resistance to pitting and crevice corrosion, while SUS304 does not contain molybdenum. Therefore, SUS316 is more suitable for coastal areas, marine environments, or handling corrosive chemicals.

SUS304 vs. SUS316: Machinability

SUS304 is more machinable than SUS316 because SUS316 hardens more easily during machining, which increases the difficulty of cutting. SUS316's advantage lies in its excellent corrosion resistance, especially against chloride corrosion, while SUS304 performs poorly in this regard.

 

SUS304 vs. SUS316: Prices

SUS304: $2.00 – $2.70 per kilogram

SUS316: $3.50 – $4.50 per kilogram

Purchasing Tips:

Market fluctuations in nickel and molybdenum can rapidly impact prices. Locking in orders early ensures a stable supply and avoids sudden cost increases.

 

What is the difference between AISI 304 and AISI 316? 

The main difference between AISI 304 and AISI 316 lies in their corrosion resistance and strength. 316 stainless steel incorporates molybdenum, resulting in better corrosion resistance (especially against chlorides) and higher strength. 304 is sufficient for most everyday food contact needs, but 316 is a better choice if the environment involves exposure to moisture or chlorides.

 

GNEE Stainless Steel is an independent stocker and processor of SUS 304/316 stainless steel. With a large inventory and excellent processing capabilities, we can meet the needs of most projects, whether stock products or custom orders. We offer: stock sizes of sheet and plate, stock lengths of round bar, fixed-length sheet and plate, fixed-length round bar, cold forming of sheet and plate and round bar, and any other necessary processing services. For any inquiries, please Email: sales@gneestainless.com.