Stainless Steel CF3A-SA (Solution annealed)
Heat-treated state · default condition
ASTM CF3A · UNS J92500
The only heat-treatment condition supplied under ASTM A351 — full carbide solution plus quench for maximum corrosion resistance and ductility.
Values for the SA condition
Other CF3A tempers and conditions
CF3A is listed in 2 conditions; see the grade overview at CF3A.
- SA
- SA-HIP
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefaultThis page Solution annealed | The only heat-treatment condition supplied under ASTM A351 — full carbide solution plus quench for maximum corrosion resistance and ductility. | 285 | 565 | 48 | 155 HB | — |
hot isostatically pressed then solution annealed | Pick for pressure-boundary or nuclear castings where internal microporosity must be closed to improve ductility, impact and fatigue life. | 290 | 580 | 55 | 158 HB | 2.4 % IACS |
What is CF3A-SA?
CF3A-SA is CF3A heat treated to SA — the only heat-treatment condition supplied under ASTM A351 — full carbide solution plus quench for maximum corrosion resistance and ductility. CF3A-SA has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 565 MPa (81.9 ksi) — weaker than 74% of stainless steel grades. Elongation at break is 48% and the elastic modulus is 193 GPa (28 Msi). CF3A-SA has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Advantages
- Readily welded — 88/100, better than 91% of stainless steel grades
- Ductile — tolerates forming and impact — 48%, better than 85% of stainless steel grades
- Low embodied carbon — 3.6 kg CO₂/kg, better than 83% of stainless steel grades
CF3A-SA properties
Typical room-temperature values for CF3A-SA; 12 are specific to this condition. Other listed values are CF3A reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
CF3A-SA has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
CF3A-SA has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 565 MPa (81.9 ksi) — weaker than 74% of stainless steel grades. Elongation at break is 48% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
CF3A-SA is rated for continuous service to 425°C (797 °F). It conducts heat at 16.2 W/m·K (9.36 BTU/hr·ft·°F), better than 64% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
CF3A-SA 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 CF3A-SA takes about 53 MJ of energy and emits 3.6 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 75%.
Manufacturability8
CF3A-SA's machinability is fair (38/100, better than 63% of stainless steel grades); weldability excellent (88/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CF3A-SA
Is CF3A easy to machine?
Gummy and strongly work-hardening — use rigid setups, sharp positive-rake carbide, heavy positive feed, low-to-moderate speed and flood coolant to avoid glazing.
Can CF3A be welded?
Excellent with 308L/309L filler by GTAW/SMAW/FCAW; the ≤0.03 %C means no post-weld solution anneal is normally needed, keep interpass low and ferrite in the 5–20 FN range.
Can CF3A be formed, bent or molded?
Sand or investment cast with good fluidity; provide generous risers and chills for heavy sections, then solution anneal above 1040 °C and water quench.
What surface finishes work on CF3A?
Grit-blast and pickle/passivate per ASTM A380/A967; electropolishing gives a bright hygienic surface — no anodizing.
CF3A 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 for as-welded corrosion resistance | ≤ 0.03 | 0.02 |
| Mn | ≤ 1.5 | 1 |
| Si | ≤ 2 | 1.2 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Cr | 17 – 21 | 19 |
| Nikept low-side to develop the δ-ferrite needed for the 'A' strength level | 8 – 12 | 9.5 |
| Moresidual | ≤ 0.5 | — |
| Fe | balance | — |
CF3A-SA — frequently asked
What is CF3A-SA used for?
CF3A-SA is typically used for valve bodies, pump casings, corrosive-service fittings and food and pharma equipment. In short: low-carbon CF3, higher strength; no post-weld anneal needed; high-ductility austenitic casting.
What is the yield strength of CF3A-SA?
CF3A-SA has a typical yield strength of 285 MPa (41.3 ksi) and a tensile strength of 565 MPa (81.9 ksi) — weaker than 74% of stainless steel grades. Strength varies by condition: see the 2 listed tempers.
Is CF3A-SA easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Gummy and strongly work-hardening — use rigid setups, sharp positive-rake carbide, heavy positive feed, low-to-moderate speed and flood coolant to avoid glazing.
Can CF3A-SA be welded?
Yes — weldability is rated excellent (88/100). Excellent with 308L/309L filler by GTAW/SMAW/FCAW; the ≤0.03 %C means no post-weld solution anneal is normally needed, keep interpass low and ferrite in the 5–20 FN range.
What surface finishes work on CF3A-SA?
Grit-blast and pickle/passivate per ASTM A380/A967; electropolishing gives a bright hygienic surface — no anodizing.
Can CF3A-SA be formed, bent or molded?
Sand or investment cast with good fluidity; provide generous risers and chills for heavy sections, then solution anneal above 1040 °C and water quench.
What is the maximum service temperature of CF3A-SA?
CF3A-SA is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CF3A-SA and CF3A SA-HIP?
SA is the default condition — the only heat-treatment condition supplied under ASTM A351 — full carbide solution plus quench for maximum corrosion resistance and ductility. SA-HIP: pick for pressure-boundary or nuclear castings where internal microporosity must be closed to improve ductility, impact and fatigue life. Yield strength is 285 MPa in SA versus 290 MPa in SA-HIP.
Sources
- ASTM A351/A351M Castings, Austenitic, for Pressure-Containing Parts — ASTM International (2023)
- ASTM A743/A744 Castings, Iron-Chromium-Nickel, Corrosion Resistant — ASTM International (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (Cast Stainless Steels) — ASM International (1990)
- Steel Castings Handbook, 6th ed. — Steel Founders' Society of America / ASM (1995)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
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.