Stainless Steel 1.4650 +AT (Solution annealed)
Heat-treated state · default condition
EN 1.4650
Standard stocked condition for wire rod, wire and bar to be cold-headed or cold-extruded; maximum ductility and corrosion resistance.
Values for the +AT condition
Other 1.4650 tempers and conditions
1.4650 is listed in 6 conditions; see the grade overview at 1.4650.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+ATDefaultThis page Solution annealed | Standard stocked condition for wire rod, wire and bar to be cold-headed or cold-extruded; maximum ductility and corrosion resistance. | 220 | 570 | 50 | 150 HB | — |
Annealed and lightly cold drawn | Choose for coil wire fed straight to multi-station headers: bright surface and straightness with almost no loss of heading ductility. | 320 | 620 | 40 | 180 HB | 2.4 % IACS |
Cold drawn to 700–850 MPa | Cold-drawn wire/bar for parts that need higher proof strength but still some upset or thread-rolling capability. | 520 | 770 | 25 | 20 HRC | 2.4 % IACS |
Cold-headed fastener, ISO 3506 property class 70 | The usual delivery class for bolts and screws cold-formed from this grade; strength comes from the heading/thread-rolling work. | 520 | 760 | 20 | 20 HRC | 2.4 % IACS |
Cold-headed fastener, ISO 3506 property class 80 | High-strength stainless fastener class from strongly drawn stock; only for small diameters where the required cold work is achievable. | 680 | 860 | 14 | 27 HRC | 2.4 % IACS |
Cold drawn to 900–1100 MPa | Heavily drawn wire for springs, clips and high-strength shafts where no further heavy cold upsetting is required. | 800 | 1,000 | 12 | 30 HRC | 2.4 % IACS |
What is 1.4650 +AT?
1.4650 +AT is 1.4650 heat treated to +AT — standard stocked condition for wire rod, wire and bar to be cold-headed or cold-extruded; maximum ductility and corrosion resistance. 1.4650 +AT has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 99% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 200 GPa (29 Msi). 1.4650 +AT has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Advantages
- Forms and bends easily — 97/100, better than 100% of stainless steel grades
- Polishes to a fine finish — 85/100, better than 97% of stainless steel grades
- Readily welded — 88/100, better than 91% of stainless steel grades
- Ductile — tolerates forming and impact — 50%, better than 90% of stainless steel grades
- Tough — resists crack growth — 200 MPa·√m (182 ksi·√in), better than 86% of stainless steel grades
Limitations
- Low strength — 220 MPa (31.9 ksi), worse than 99% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
1.4650 +AT properties
Typical room-temperature values for 1.4650 +AT; 12 are specific to this condition. Other listed values are 1.4650 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4650 +AT has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
1.4650 +AT has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 99% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1.4650 +AT is rated for continuous service to 400°C (752 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
1.4650 +AT conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 56% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4650 +AT takes about 57 MJ of energy and emits 4.5 kg of CO₂ — more than 62% of stainless steel grades. Typical recycled content is 65%.
Manufacturability7
1.4650 +AT's machinability is fair (40/100, better than 72% of stainless steel grades); weldability excellent (88/100); formability excellent (97/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4650 +AT
Is 1.4650 easy to machine?
Machine like 304L — sharp positive tools, rigid setup, 60–120 m/min carbide, heavy flood coolant; it work-hardens and is gummy, so avoid dwelling and use free-cutting grades if turning dominates.
Can 1.4650 be welded?
Excellent with TIG/MIG/resistance welding using 308L/347 filler; no post-weld anneal needed thanks to ≤0.03 % C, keep heat input moderate to limit distortion.
Can 1.4650 be formed, bent or molded?
This is the grade's strength: low work-hardening allows multi-blow cold heading, cold extrusion and thread rolling with lower forces and better die life than 304; anneal between severe operations if reductions exceed ~60 %.
What surface finishes work on 1.4650?
Passivate or electropolish after forming to restore the chromium oxide film; takes a bright mechanical polish, can be PVD-coated, but cannot be anodized.
1.4650 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Clow carbon — sensitisation resistant | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.5 |
| Mn | ≤ 2 | 1.2 |
| P | ≤ 0.05 | 0.03 |
| Slow S for cold-heading ductility | ≤ 0.02 | 0.01 |
| Cr | 18 – 20 | 19 |
| Ni | 9 – 11 | 10 |
| Culowers work-hardening rate | 1 – 3 | 2 |
| Nkept low to limit hardening | ≤ 0.11 | 0.04 |
| Fe | balance | — |
1.4650 +AT — frequently asked
What is 1.4650 +AT used for?
1.4650 +AT is typically used for cold-headed fasteners, welded cold-formed components, rivets and clinch studs, cold-extruded shafts and pins, thread-rolled screws to A2-70/A2-80 and deep-drawn housings and cups. In short: weldable heading stainless; highest formability in family; no sensitization from welding.
What is the yield strength of 1.4650 +AT?
1.4650 +AT has a typical yield strength of 220 MPa (31.9 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 99% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 1.4650 +AT easy to machine?
Not especially — machinability is rated fair (40/100, better than 72% of stainless steel grades). Machine like 304L — sharp positive tools, rigid setup, 60–120 m/min carbide, heavy flood coolant; it work-hardens and is gummy, so avoid dwelling and use free-cutting grades if turning dominates.
Can 1.4650 +AT be welded?
Yes — weldability is rated excellent (88/100). Excellent with TIG/MIG/resistance welding using 308L/347 filler; no post-weld anneal needed thanks to ≤0.03 % C, keep heat input moderate to limit distortion.
What surface finishes work on 1.4650 +AT?
Passivate or electropolish after forming to restore the chromium oxide film; takes a bright mechanical polish, can be PVD-coated, but cannot be anodized.
Can 1.4650 +AT be formed, bent or molded?
This is the grade's strength: low work-hardening allows multi-blow cold heading, cold extrusion and thread rolling with lower forces and better die life than 304; anneal between severe operations if reductions exceed ~60 %.
What is the maximum service temperature of 1.4650 +AT?
1.4650 +AT is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4650 +AT and 1.4650 A2-80?
+AT is the default condition — standard stocked condition for wire rod, wire and bar to be cold-headed or cold-extruded; maximum ductility and corrosion resistance. A2-80: high-strength stainless fastener class from strongly drawn stock; only for small diameters where the required cold work is achievable. Yield strength is 220 MPa in +AT versus 680 MPa in A2-80.
Sources
- EN 10088-3 — Stainless steels: semi-finished products, bars, rods, wire, sections — CEN (2014)
- EN 10263-5 — Steel rod, bars and wire for cold heading and cold extrusion: stainless steels — CEN (2017)
- EN 10088-1 — Stainless steels: list of stainless steels (physical properties) — CEN (2014)
- ISO 3506-1 — Fasteners: mechanical properties of corrosion-resistant stainless steel fasteners — ISO (2020)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.