Stainless Steel 205-ANN (Annealed)
Heat-treated state · default condition
AISI/SAE 205 · UNS S20500
Pick for maximum ductility and forming/deep-drawing before any hardening by cold work.
Values for the ANN condition
Other 205 tempers and conditions
205 is listed in 5 conditions; see the grade overview at 205.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefaultThis page Annealed | Pick for maximum ductility and forming/deep-drawing before any hardening by cold work. | 475 | 830 | 58 | 230 HB | — |
Quarter hard | Pick when moderate strength gain is needed but the part still has to be bent or moderately formed. | 760 | 1,035 | 25 | 25 HRC | — |
Half hard | Pick for structural strip, clamps and brackets needing high yield strength with limited bending. | 965 | 1,240 | 15 | 32 HRC | — |
Three-quarter hard | Pick for spring-like flat parts and high-load stampings with only gentle forming radii. | 1,140 | 1,380 | 12 | 37 HRC | — |
Full hard | Pick for maximum strength flat springs, shims and retaining parts where forming is limited to shallow bends. | 1,310 | 1,520 | 8 | 42 HRC | — |
What is 205-ANN?
205-ANN is 205 heat treated to ANN — pick for maximum ductility and forming/deep-drawing before any hardening by cold work. 205-ANN has a yield strength of 475 MPa (68.9 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 74% of stainless steel grades. Elongation at break is 58% and the elastic modulus is 197 GPa (28.6 Msi). 205-ANN has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,385°C (2,525 °F).
Advantages
- Ductile — tolerates forming and impact — 58%, better than 100% of stainless steel grades
- Low embodied carbon — 3.4 kg CO₂/kg, better than 91% of stainless steel grades
Limitations
- Needs corrosion protection — 46/100, worse than 82% of stainless steel grades
205-ANN properties
Typical room-temperature values for 205-ANN; 17 are specific to this condition. Other listed values are 205 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
205-ANN has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,385°C (2,525 °F).
Mechanical16
205-ANN has a yield strength of 475 MPa (68.9 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 74% of stainless steel grades. Elongation at break is 58% and the elastic modulus is 197 GPa (28.6 Msi).
Thermal6
205-ANN is rated for continuous service to 800°C (1,472 °F). It conducts heat at 14.5 W/m·K (8.38 BTU/hr·ft·°F), worse than 72% of stainless steel grades. Thermal expansion is 16.9 µm/m·K (9.39 µin/in·°F).
Electrical3
205-ANN conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (46/100), worse than 82% of stainless steel grades.
Sustainability4
Producing a kilogram of 205-ANN takes about 48 MJ of energy and emits 3.4 kg of CO₂ — less than 85% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
205-ANN's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability good (55/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 205-ANN
Is 205 easy to machine?
Treat as a difficult austenitic: rigid setups, positive-rake sharp carbide, heavy feeds and flood coolant to cut under the work-hardened skin — never dwell or rub.
Can 205 be welded?
GTAW/GMAW/resistance welding with 209 or 308L/307 type filler and low heat input; avoid pre-heat, and expect loss of the cold-worked strength in the HAZ.
Can 205 be formed, bent or molded?
Very high work-hardening rate — size presses for ~1.5–2× the load used for 304, use generous bend radii and interstage annealing at 1010–1120 °C followed by rapid cooling.
What surface finishes work on 205?
Not anodizable; passivate per ASTM A967 (nitric or citric) after machining, or electropolish/mechanically polish to BA or No.4 finish.
205 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 |
|---|---|---|
| C | 0.12 – 0.25 | 0.18 |
| MnNi-replacing austenite stabiliser | 14 – 15.5 | 14.8 |
| Si | ≤ 1 | 0.5 |
| P | ≤ 0.06 | 0.03 |
| S | ≤ 0.03 | 0.02 |
| Cr | 16.5 – 18 | 17.2 |
| Ni | 1 – 1.75 | 1.4 |
| Nprincipal strengthener | 0.32 – 0.4 | 0.36 |
| Fe | balance | — |
205-ANN — frequently asked
What is 205-ANN used for?
205-ANN is typically used for structural components, fasteners and transportation parts. In short: strongest 200-series austenitic; nitrogen-strengthened, low nickel; hard to machine.
What is the yield strength of 205-ANN?
205-ANN has a typical yield strength of 475 MPa (68.9 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 74% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 205-ANN easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Treat as a difficult austenitic: rigid setups, positive-rake sharp carbide, heavy feeds and flood coolant to cut under the work-hardened skin — never dwell or rub.
Can 205-ANN be welded?
Yes — weldability is rated good (55/100). GTAW/GMAW/resistance welding with 209 or 308L/307 type filler and low heat input; avoid pre-heat, and expect loss of the cold-worked strength in the HAZ.
What surface finishes work on 205-ANN?
Not anodizable; passivate per ASTM A967 (nitric or citric) after machining, or electropolish/mechanically polish to BA or No.4 finish.
Can 205-ANN be formed, bent or molded?
Very high work-hardening rate — size presses for ~1.5–2× the load used for 304, use generous bend radii and interstage annealing at 1010–1120 °C followed by rapid cooling.
What is the maximum service temperature of 205-ANN?
205-ANN is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 205-ANN and 205-FH?
ANN is the default condition — pick for maximum ductility and forming/deep-drawing before any hardening by cold work. FH: pick for maximum strength flat springs, shims and retaining parts where forming is limited to shallow bends. Yield strength is 475 MPa in ANN versus 1,310 MPa in FH.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip — ASTM International (2023)
- ASTM A666 — Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate and Flat Bar — ASTM International (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Specialty Handbook — Stainless Steels — ASM International (1994)
- Machinery's Handbook (machinability ratings for stainless steels) — Industrial Press (2020)
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.