Stainless Steel CF3A
Grade
ASTM CF3 · UNS J92500 · EN 1.4306, GX2CrNi19-11 · JIS SCS19, SCS19A · GB ZG03Cr19Ni10
CF3A = higher-ferrite chemistry variant, solution annealed
Pick when higher strength is needed from the same low-carbon chemistry; ferrite number is raised via Cr/Ni balance.
Values for the CF3A condition
Other CF3 tempers and conditions
CF3 is listed in 4 conditions; see the grade overview at CF3.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Only for non-pressure, non-corrosive decorative or structural parts; not permitted by A351/A743 for service castings. | 240 | 480 | 35 | 145 HB | 2.3 % IACS |
SADefault Solution annealed | Standard as-supplied condition for all A351/A743 CF3 castings; maximum corrosion resistance and ductility. | 250 | 520 | 58 | 140 HB | — |
Centrifugally cast (A451 CPF3), solution annealed | Choose for pressure piping and cylindrical parts: denser, cleaner structure than static castings with slightly higher strength. | 265 | 540 | 52 | 150 HB | 2.3 % IACS |
CF3AThis page Higher-ferrite chemistry variant, solution annealed | Pick when higher strength is needed from the same low-carbon chemistry; ferrite number is raised via Cr/Ni balance. | 300 | 570 | 45 | 160 HB | 2.4 % IACS |
What is CF3A?
CF3A is CF3 in the CF3A grade — pick when higher strength is needed from the same low-carbon chemistry; ferrite number is raised via Cr/Ni balance. CF3A has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi). CF3A 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). SA is the default condition FabDigit quotes; CF3A is available on request or by drawing note.
Advantages
- Readily welded — 85/100, better than 87% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Hard to polish — 60/100, worse than 80% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
- Limited formability — 25/100, worse than 78% of stainless steel grades
CF3A properties
Typical room-temperature values for CF3A; 23 are specific to this condition. Other listed values are CF3 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
CF3A 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).
Mechanical16
CF3A has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
CF3A is rated for continuous service to 400°C (752 °F). It conducts heat at 16.7 W/m·K (9.65 BTU/hr·ft·°F), better than 70% of stainless steel grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).
Electrical3
CF3A conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 52% of stainless steel grades.
Sustainability4
Producing a kilogram of CF3A takes about 55 MJ of energy and emits 5 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 70%.
Manufacturability8
CF3A's machinability is fair (38/100, better than 63% of stainless steel grades); weldability excellent (85/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CF3A
Is CF3 easy to machine?
Gummy and work-hardening — use rigid setups, sharp positive-rake carbide, heavy feed with no dwell, and flood coolant; expect ~40 % of 1212 speed.
Can CF3 be welded?
Excellent with GTAW/SMAW using 308L/ER308L filler; the ≤0.03 % C removes the need for post-weld solution annealing in most services.
Can CF3 be formed, bent or molded?
Sand or investment cast with generous risering; delta ferrite (FN 5–15) controls hot tearing, and A351 requires solution treatment above 1040 °C with rapid quench.
What surface finishes work on CF3?
Pickle and passivate (ASTM A380/A967) after casting and welding; electropolishing gives a hygienic surface — anodising does not apply.
CF3 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 weld-decay resistance | ≤ 0.03 | 0.02 |
| Mn | ≤ 1.5 | 1 |
| Siaids casting fluidity | ≤ 2 | 1.2 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.04 | 0.02 |
| Cr | 17 – 21 | 19 |
| Ni | 8 – 12 | 10 |
| Moresidual only | ≤ 0.5 | 0.2 |
| Fe | balance | — |
CF3A — frequently asked
What is CF3A used for?
CF3A is typically used for welded pump casings, chemical valve bodies and food/beverage fittings. In short: cast 304L equivalent; best as-welded cast austenitic; no post-weld anneal needed.
What is the yield strength of CF3A?
CF3A has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 68% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is CF3A easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Gummy and work-hardening — use rigid setups, sharp positive-rake carbide, heavy feed with no dwell, and flood coolant; expect ~40 % of 1212 speed.
Can CF3A be welded?
Yes — weldability is rated excellent (85/100). Excellent with GTAW/SMAW using 308L/ER308L filler; the ≤0.03 % C removes the need for post-weld solution annealing in most services.
What surface finishes work on CF3A?
Pickle and passivate (ASTM A380/A967) after casting and welding; electropolishing gives a hygienic surface — anodising does not apply.
Can CF3A be formed, bent or molded?
Sand or investment cast with generous risering; delta ferrite (FN 5–15) controls hot tearing, and A351 requires solution treatment above 1040 °C with rapid quench.
What is the maximum service temperature of CF3A?
CF3A 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 CF3-SA and CF3A?
SA is the default condition — standard as-supplied condition for all A351/A743 CF3 castings; maximum corrosion resistance and ductility. CF3A: pick when higher strength is needed from the same low-carbon chemistry; ferrite number is raised via Cr/Ni balance. Yield strength is 250 MPa in SA versus 300 MPa in CF3A.
Sources
- ASTM A351/A351M — Castings, Austenitic, for Pressure-Containing Parts — ASTM International (2018)
- ASTM A743/A743M — Castings, Iron-Chromium-Nickel, Corrosion Resistant, for General Application — ASTM International (2021)
- ASTM A451/A451M — Centrifugally Cast Austenitic Steel Pipe for High-Temperature Service — ASTM International (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (Cast Stainless Steels) — ASM International (1990)
- EN 10283 / EN 10213 — Corrosion resistant steel castings (GX2CrNi19-11, 1.4306/1.4309) — CEN (2010)
- GB/T 12230 — (ZG03Cr19Ni10) — SAC (2016)
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.