Stainless Steel 301
Designation and Standards
Section titled “Designation and Standards”| Designation | Standard / Equivalent |
|---|---|
| AISI | 301 |
| UNS | S30100 |
| EN | X10CrNi18-8 (1.4310) |
| JIS | SUS301 |
| BS | 301S21 |
| SS | 2331 |
Chemical Composition
Section titled “Chemical Composition”| Element | Content (% by weight) |
|---|---|
| Carbon (C) | ≤ 0.15 |
| Manganese (Mn) | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 |
| Chromium (Cr) | 16.0 – 18.0 |
| Nickel (Ni) | 6.0 – 8.0 |
| Iron (Fe) | Balance |
Mechanical Properties
Section titled “Mechanical Properties”Values depend on the degree of cold work. The table shows typical properties per ASTM A666 standard for the most common supply conditions.
| Condition | Yield Strength (MPa) | Tensile Strength (MPa) | Elongation in 50 mm (%) | Rockwell Hardness |
|---|---|---|---|---|
| Annealed | 205 (30 ksi) | 515 (75 ksi) | 55 min | 85 HRB max |
| 1/4 Hard | 515 (75 ksi) | 860 (125 ksi) | 25 min | 25 HRC max |
| 1/2 Hard | 755 (110 ksi) | 1035 (150 ksi) | 18 min | 32 HRC max |
| 3/4 Hard | 930 (135 ksi) | 1205 (175 ksi) | 12 min | 37 HRC max |
| Full Hard | 965 (140 ksi) | 1275 (185 ksi) | 8 min | 41 HRC max |
Other elastic constants (at room temperature):
- Modulus of Elasticity: 193 GPa (28.0 × 10⁶ psi) – range 189–197 GPa
- Shear Modulus: 76 GPa (11.0 × 10⁶ psi)
- Poisson’s Ratio: 0.27
Physical Properties
Section titled “Physical Properties”| Property | SI Value | Imperial Value |
|---|---|---|
| Density | 7.93 g/cm³ | 0.286 lb/in³ |
| Melting Point | 1400 – 1420 °C | 2550 – 2590 °F |
| Crystal Structure | Face-centered cubic (unstable austenite) | |
| Magnetism | Slightly magnetic after cold deformation |
Thermal Properties
Section titled “Thermal Properties”| Property | SI Value | Imperial Value |
|---|---|---|
| Coefficient of Thermal Expansion (20–100 °C) | 16.5 – 18.5 µm/m·K | 9.2 – 10.3 µin/in·°F |
| Thermal Conductivity at 100 °C | 15 – 17 W/m·K | 104 – 118 BTU·in/h·ft²·°F |
| Specific Heat | 490 – 530 J/kg·K | 0.117 – 0.127 BTU/lb·°F |
| Maximum Service Temperature in Oxidizing Atmosphere | 750 – 900 °C | 1380 – 1650 °F |
Electrical Properties
Section titled “Electrical Properties”| Property | Value |
|---|---|
| Electrical Resistivity | 65 – 77 µΩ·cm (0.65 – 0.77 µΩ·m) |
Corrosion Resistance
Section titled “Corrosion Resistance”It exhibits excellent general resistance, with a rating of 5 (excellent) in the following environments: fresh water, sea water, organic solvents, oxidation at 500 °C, weak acids, weak alkalis, and UV radiation. In strong acids the resistance is good (rating 4). Surface wear has a rating of 4, while flammability is 5.
Compared to other stainless steels, 301 offers slightly lower resistance than 304, especially in chloride media. It is susceptible to stress corrosion cracking in atmospheres containing chlorides at temperatures above 60 °C. For aggressive marine environments, molybdenum grades such as 316 are recommended.
Applications by Industry
Section titled “Applications by Industry”| Industry | Applications |
|---|---|
| Automotive | Trim, moldings, clamps, springs, exhaust components |
| Aerospace | Structural fuselage parts, brackets, and fasteners requiring high strength after forming |
| Railway Transport | Body panels, lightweight structural profiles |
| Appliances and Housewares | Sinks, trays, washing machine drums, kitchen equipment |
| Food Industry | Conveyors, hoppers, and work surfaces requiring moderate corrosion resistance |
| Medical and Instrumentation | Housings, non-critical instruments, and hospital furniture |
Comparison with Similar Materials
Section titled “Comparison with Similar Materials”| Property | 301 | 304 | 316 |
|---|---|---|---|
| Maximum Mechanical Strength by Cold Work | Very high (up to ~1275 MPa) | High (up to ~860 MPa) | High (up to ~860 MPa) |
| General Corrosion Resistance | Good | Better | Excellent (Mo presence) |
| Pitting Resistance (PREN) | ~18 | ~18 | ~24 |
| Weldability | Good (possible sensitization) | Excellent | Excellent |
| Relative Cost | Medium | Medium | High |
Stainless steel 301 is distinguished by its ability to harden drastically through cold work, reaching strengths typical of martensitic steels, while maintaining useful ductility. Compared to 304, it sacrifices some corrosion resistance to gain mechanical properties after forming. In applications requiring maximum strength without quench heat treatments, 301 is often the choice.
Frequently Asked Questions (FAQ)
Section titled “Frequently Asked Questions (FAQ)”What is the tensile strength of Stainless Steel 301 in the annealed condition?
Section titled “What is the tensile strength of Stainless Steel 301 in the annealed condition?”The minimum tensile strength is 515 MPa (75 ksi) and can rise up to 620 MPa depending on thickness.
What is the typical hardness of 301 in the full hard condition?
Section titled “What is the typical hardness of 301 in the full hard condition?”A hardness of approximately 41 HRC is reached, equivalent to about 375 HB on the Brinell scale.
How much chromium does steel 301 contain?
Section titled “How much chromium does steel 301 contain?”The chromium content is between 16% and 18%, sufficient to ensure the protective passive layer.
What is the thermal conductivity at room temperature?
Section titled “What is the thermal conductivity at room temperature?”The thermal conductivity is approximately 15 W/m·K (8.7 BTU/h·ft·°F), notably lower than that of carbon steels.
At what temperature does Stainless Steel 301 melt?
Section titled “At what temperature does Stainless Steel 301 melt?”Its melting point is in the range of 1400–1420 °C (2550–2590 °F).
What is the density of stainless steel 301?
Section titled “What is the density of stainless steel 301?”The typical density is 7.93 g/cm³ (0.286 lb/in³), a common value for chromium-nickel austenitic stainless steels.
References
Section titled “References”- azom.com: https://www.azom.com/properties.aspx?ArticleID=960
- engineeringtoolbox.com: https://www.engineeringtoolbox.com/stainless-steel-classifications-d_368.html
- steelnumber.com: https://www.steelnumber.com/en/equivalent_steel_iron_eu.php?zname_id=2991