The Difference Between Stainless Steel 304 And 316

Even though stainless steel 304 and 316 similar, but they also have many differences , for the details, please see below:

1. Chemical Composition

The primary difference between 304 and 316 stainless steel lies in their chemical makeup:

• 304 Stainless Steel (A2 Stainless Steel)

                                                                         Chemical Composition(%)

  Chemical Component	C	Si	Mn	P	S	Ni	Cr	N
  Min						8.000	17.000
  Max	0.080	1.000	2.000	0.045	0.030	11.000	19.000	0.100

  304 Stainless Steel Mechanical Properties

                                                                        Mechanical properties

  Yield Strength	Tensile Strength	Elongation	Reduction	Hardness
  Mpa	Mpa	%	%	HRB
  205	520	40	30	80

• 316 Stainless Steel (A4 Stainless Steel)

                                                                       Chemical Composition(%)

  Chemical Component	C	Si	Mn	P	S	Ni	Cr	Mo
  Min						10.000	16.000	2.000
  Max	0.080	1.000	2.000	0.045	0.030	14.000	18.000	3.000

  316 Stainless Steel Mechanical Properties

                                                                           Mechanical properties

  Yield Strength	Tensile Strength	Elongation	Reduction	Hardness
  Mpa	Mpa	%	%	HRB
  170	485	30	50	80

The addition of molybdenum in 316 significantly enhances its corrosion resistance, especially against chlorides and acids.

2. Corrosion Resistance

• 304 Stainless Steel performs well in most environments but is susceptible to chloride corrosion (e.g., seawater, de-icing salts).

• 316 Stainless Steel offers superior resistance to saltwater, acids, and industrial chemicals due to molybdenum, making it ideal for marine and chemical applications.

3. Strength and Durability

• 316 has slightly higher tensile strength (580 MPa vs. 515 MPa for 304).

• 304 is more ductile, making it easier to form and weld.

4. Temperature Resistance

• Both grades perform well in high temperatures, but 316 maintains better strength and oxidation resistance at extreme temperatures.

5. Cost

• 316 is more expensive due to its molybdenum content and enhanced properties.

6. Common Applications

304 Stainless Steel Uses:

• Kitchen equipment (sinks, appliances)

• Food processing machinery

• Architectural trim & automotive parts

• Chemical containers (for mild environments)

316 Stainless Steel Uses:

• Marine hardware (boat fittings, offshore platforms)

• Medical & pharmaceutical equipment

• Chemical & petrochemical processing

• Coastal construction (bridges, railings)

Conclusion

Choosing between 304 and 316 stainless steel depends on the environment and application:

• Use 304 for general-purpose, cost-effective applications with minimal exposure to chlorides.

• Choose 316 for harsh conditions (marine, chemical, medical) where superior corrosion resistance is needed.

Understanding these differences ensures optimal performance and longevity in your projects.