What material is 1.4541 equivalent to?
The material AISI 321 is an austenitic stainless steel that is also known under the designations 1.4541, Alloy 321, BS 321S31, BS 321S51 and X6CrNiTi18-10. The material is a V2A steel that has been stabilised by the addition of titanium and is characterised by good corrosion resistance (PREN value 17.0 to 19.0).
What is 1.4571 steel equivalent to?
1.4571 stainless steel is equivalent to AISI 316Ti and UNS S31635. It is a titanium-stabilized austenitic stainless steel with excellent high-temperature resistance.
1.4541 (SS 321) Vs 1.4571 (SS 316Ti)：Chemical Composition (by weight percentage)
| Element | 1.4541 (AISI 321) | 1.4571 (AISI 316Ti) |
|---|---|---|
| Carbon (C) | ≤ 0.08% | ≤ 0.08% |
| Chromium (Cr) | 17.0-19.0% | 16.5-18.5% |
| Nickel (Ni) | 9.0-12.0% | 10.5-13.5% |
| Titanium (Ti) | ≥ 5x C (approx. 0.7%) | ≥ 5x C (approx. 0.5%) |
| Molybdenum (Mo) | - | 2.0-2.5% |
| Manganese (Mn) | ≤ 2.0% | ≤ 2.0% |
| Silicon (Si) | ≤ 1.0% | ≤ 1.0% |
| Phosphorus (P) | ≤ 0.045% | ≤ 0.045% |
| Sulfur (S) | ≤ 0.015% | ≤ 0.015% |
1.4541 (SS 321) Vs 1.4571 (SS 316Ti)：Mechanical Properties
| Property | 1.4541 (Alloy 321) | 1.4571 (Alloy 316Ti) |
|---|---|---|
| Tensile Strength (Rm) | 500-700 MPa | 500-700 MPa |
| Yield Strength (Rp0.2) | ≥ 190 MPa | ≥ 200 MPa |
| Elongation (A5) | ≥ 40% | ≥ 40% |
| Hardness (HB) | ≤ 215 | ≤ 215 |
| Density (ρ) | 7.9 g/cm³ | 7.9 g/cm³ |
1.4541 (SS 321) Vs 1.4571 (SS 316Ti)：Temperature Range
| Temperature Properties | 1.4541 (SS 321) | 1.4571 (SS 316Ti) |
|---|---|---|
| Maximum Operating Temp. | Up to 800°C | Up to 600°C |
| Resistance to Sensitization | Excellent (Ti-stabilized) | Excellent (Ti-stabilized) |
Corrosion Resistance
1.4541
Oxidation Resistance: Excellent in oxidizing environments (e.g., steam, combustion gases) up to 900°C .
Limitations: Susceptible to pitting in chloride-rich environments (e.g., seawater) due to the absence of molybdenum .
1.4571
Chloride Resistance: Molybdenum and titanium combination provides superior resistance to pitting, crevice corrosion, and stress corrosion cracking (SCC) in chloride media .
High-Temperature Stability: Resistant to oxidation up to 870°C and performs well in chemical processing (e.g., acids, alkalis) .
Weldability and Processing
1.4541
Welding: Readily weldable using standard methods (e.g., TIG, MIG) without post-weld heat treatment, thanks to titanium stabilization .
Machining: Requires sharp tools due to moderate work-hardening tendency .
1.4571
Welding: Excellent weldability with minimal risk of intergranular corrosion; compatible with 316L or 316Ti filler metals .
Machining: Similar to 1.4541 but slightly more challenging due to molybdenum content .
Applications
1.4541 stainless steel High-Temperature Use: Ideal for furnace components, heat exchangers, and automotive exhaust systems.
1.4571 stainless steel for marine engineering (e.g., docks, offshore structures), chemical reactors, and pharmaceutical pipelines exposed to chlorides.