What is 1.4401 stainless steel?
1.4401 is an austenitic stainless steel, also known as AISI 316, that contains chromium, nickel, and molybdenum. The addition of molybdenum gives it superior corrosion resistance, especially in chloride-containing environments, compared to 1.4301 (AISI 304). Due to its properties, it is widely used in chemical, petrochemical, food, and medical industries.
What is the equivalent of 1.4401 stainless steel?
The European standard EN 1.4401 is equivalent to the American standard AISI 316 or UNS S31600. This is an austenitic stainless steel that is known for its enhanced corrosion resistance, especially in chloride environments, due to its molybdenum content.
What is the composition of 1.4401 material?
EN 1.4401 grade 316 stainless steel (16% chromium, 10% nickel and 2% molybdenum) is the second most important austenitic Stainless Steel compared to 304. 316 added molybdenum and higher nickel content gives it greater corrosion resistance in many aggressive environments compared to 304.
|
|
C |
Mn |
Si |
P |
S |
Cr |
Mo |
Ni |
N |
|
Min |
|
|
|
|
|
16.0 |
2.0 |
10.0 |
|
|
Max |
0.08 |
2.0 |
0.75 |
0.045 |
0.03 |
18.0 |
3.0 |
14.0 |
0.10 |
1.4401 Mechanical Properties
|
Yield Strength 0.2% (MPa) min |
Tensile strength (MPa) min |
Elongation (% in 50mm) min |
Rockwell B (HR B) max |
Brinell (HB) max |
|
205 |
515 |
40 |
95 |
217 |
1.4401 Physical Properties
|
Density (kg/ m cube) |
Elastic Modulus (GPa) |
Specific heat 0-100°C (J/kg.K) |
Electrical resistivity (nΩ.m) |
|
8000 |
193 |
500 |
740 |
Mean Coefficient of Thermal Expansion (μm/m/°C)
|
0-100°C |
0-315°C |
0-538°C |
|
15.9 |
16.2 |
17.5 |
Thermal Conductivity (W/m.K)
|
at 100°C |
at 500°C |
|
16.3 |
21.5
|
1.4401 Corrosion Resistance and Oxidation Resistance
316 stainless steel exhibits excellent corrosion resistance and oxidation resistance in a variety of atmospheric environments and corrosive substances, generally showing better corrosion resistance than 304 stainless steel.
316 stainless steel is prone to stress corrosion cracking above approximately 60°C (140°F) and is susceptible to pitting and crevice corrosion in warm chloride environments.
At room temperature (20°C (68°F) to 25°C (77°F), 316 stainless steel can withstand drinking water containing chloride concentrations up to approximately 1000 mg/L; at approximately 60°C (140°F), the tolerance concentration drops to approximately 500 mg/L.
Welding
EN 1.4401 316 Stainless Steel cannot be hardened by thermal treatment.1.4401 Stainless Steel provides excellent welding with and without filler metals using standard fusion methods. Heavy welded sections require post-weld annealing for optimal corrosion resistance.
For optimal annealing heat to 1010-1120°C (1850-2048°F) and cool rapidly with air or water.
What is the difference between 304 and 1.4401?
The main difference is that 304 (or 1.4301) is an austenitic stainless steel with a standard composition, while 1.4401 (or 316) is an austenitic stainless steel with an added element of molybdenum which gives it superior corrosion resistance. This makes 1.4401 the preferred choice for harsh environments like those exposed to saltwater or chemicals, whereas 304 is a versatile, cost-effective option for general-purpose applications.
What is the difference between 1.4401 and 1.4404 stainless steel?
The main difference lies in the carbon content. 1.4401 has a maximum carbon content of 0.07%, while 1.4404 has a significantly lower carbon content, with a maximum of only 0.03%. The lower carbon content of 1.4404 (also known as 316L) improves its weldability and post-weld resistance to intergranular corrosion.