Stainless Steel CF8A
ASTM CF8A · UNS J92600
CF8A (UNS J92600) is the high-strength variant of CF8, a 19Cr-9Ni cast austenitic stainless steel with elevated tensile and yield requirements per ASTM A351: 275 MPa yield, 550 MPa tensile, 50 % elongation and 155 HB (82 HRB).
Reference datasheet — CF8A is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the SA condition
CF8A tempers and conditions
CF8A is supplied in 4 conditions, soft to hard. SA is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Only for non-pressure, non-corrosive structural parts; carbides at grain boundaries make it unacceptable for ASTM A351 service. | 260 | 500 | 30 | 170 HB | 2.4 % IACS |
SADefault Solution annealed (≥1040 °C, water quenched), static sand/investment… | Standard supply condition for all ASTM A351 CF8A pressure castings; maximum corrosion resistance and toughness. | 275 | 550 | 50 | 155 HB | — |
Hot isostatically pressed then solution annealed | Use where internal microporosity must be eliminated for fatigue-critical or high-integrity radiographed castings. | 285 | 570 | 55 | 155 HB | 2.4 % IACS |
Centrifugally cast tube/ring, solution annealed | Choose for cylindrical pressure parts (pipe, valve liners) where centrifugal soundness raises strength and lowers porosity. | 300 | 585 | 45 | 160 HB | 2.4 % IACS |
What is CF8A?
CF8A (UNS J92600) is the high-strength variant of CF8, a 19Cr-9Ni cast austenitic stainless steel with elevated tensile and yield requirements per ASTM A351: 275 MPa yield, 550 MPa tensile, 50 % elongation and 155 HB (82 HRB). It is used for pressure-containing castings that need extra mechanical margin, and is available solution annealed, centrifugally cast, HIP-treated or as-cast. Maximum service temperature is 650 °C with a corrosion resistance score of 68. Carbon is higher than CF3A, so sensitisation after welding or long exposure in the 450–850 °C range is the main limit; CF3A is the low-carbon alternative. CF8A 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). CF8A has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 77% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 195 GPa (28.3 Msi).
What is CF8A used for?
- valve bodies
- pump housings
- pressure vessel fittings
- general chemical service castings
Advantages
- Ductile — tolerates forming and impact — 50%, better than 90% of stainless steel grades
- Readily welded — 80/100, better than 80% of stainless steel grades
Limitations
- Limited formability — 15/100, worse than 91% of stainless steel grades
- Hard to polish — 60/100, worse than 80% of stainless steel grades
- Low strength — 275 MPa (39.9 ksi), worse than 77% of stainless steel grades
CF8A properties
Typical room-temperature values for CF8A-SA; bars are the position among stainless steel grades.
Physical3
CF8A 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
CF8A has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 77% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
CF8A is rated for continuous service to 650°C (1,202 °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 17 µm/m·K (9.44 µin/in·°F).
Electrical3
CF8A conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 63% of stainless steel grades.
Sustainability4
Producing a kilogram of CF8A takes about 53 MJ of energy and emits 4.5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 80%.
Manufacturability8
CF8A's machinability is fair (40/100, better than 72% of stainless steel grades); weldability very good (80/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. CF8A is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CF8A
Is CF8A easy to machine?
Machine like 304: rigid setups, sharp positive-rake carbide, heavy positive feed to cut under the work-hardened skin, flood coolant, and expect abrasive casting scale on the first pass.
Can CF8A be welded?
Excellent weldability with GTAW/SMAW using E308/ER308 (or 308L for corrosive duty); the 5–20 % ferrite suppresses hot cracking, no preheat needed, keep interpass below ~150 °C.
Can CF8A be formed, bent or molded?
Sand or investment cast with generous risering — long freezing range and 2.2 % solidification shrinkage require good gating; solution anneal ≥1040 °C with water quench after casting/repair welding.
CF8A 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 | ≤ 0.08 | 0.06 |
| Mn | ≤ 1.5 | 1 |
| Si | ≤ 2 | 1.3 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.04 | 0.02 |
| Cr | 18 – 21 | 19.5 |
| Nibalanced toward the low side to raise ferrite and meet the higher CF8A strength | 8 – 11 | 9 |
| Moresidual, per A351 supplementary limits | ≤ 0.5 | 0.2 |
| Fe | balance |
What surface finishes work on CF8A?
Passivate per ASTM A967 (nitric or citric) after machining; shot blast plus pickling removes casting scale, and electropolishing gives sanitary finishes though porosity limits mirror polish.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel CF8A in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J92600
How much does CF8A cost?
CF8A is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
CF8A — frequently asked
What is CF8A used for?
CF8A is typically used for valve bodies, pump housings, pressure vessel fittings and general chemical service castings. In short: high-strength CF8 variant; 650 °C service capability; standard 19Cr-9Ni casting.
What is the yield strength of CF8A?
CF8A has a typical yield strength of 275 MPa (39.9 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 77% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is CF8A easy to machine?
Not especially — machinability is rated fair (40/100, better than 72% of stainless steel grades). Machine like 304: rigid setups, sharp positive-rake carbide, heavy positive feed to cut under the work-hardened skin, flood coolant, and expect abrasive casting scale on the first pass.
Can CF8A be welded?
Yes — weldability is rated very good (80/100). Excellent weldability with GTAW/SMAW using E308/ER308 (or 308L for corrosive duty); the 5–20 % ferrite suppresses hot cracking, no preheat needed, keep interpass below ~150 °C.
What surface finishes work on CF8A?
Passivate per ASTM A967 (nitric or citric) after machining; shot blast plus pickling removes casting scale, and electropolishing gives sanitary finishes though porosity limits mirror polish.
Can CF8A be formed, bent or molded?
Sand or investment cast with generous risering — long freezing range and 2.2 % solidification shrinkage require good gating; solution anneal ≥1040 °C with water quench after casting/repair welding.
What is the maximum service temperature of CF8A?
CF8A is rated for continuous use to about 650°C (1,202 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CF8A-SA and CF8A SA-CENT?
SA is the default condition — standard supply condition for all ASTM A351 CF8A pressure castings; maximum corrosion resistance and toughness. SA-CENT: choose for cylindrical pressure parts (pipe, valve liners) where centrifugal soundness raises strength and lowers porosity. Yield strength is 275 MPa in SA versus 300 MPa in SA-CENT.
How much does CF8A cost?
CF8A is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A351/A351M — Castings, Austenitic, for Pressure-Containing Parts — ASTM International (2018)
- 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)
- Steel Castings Handbook, 6th ed. — Steel Founders' Society of America / ASM (1995)
- GB/T 12230 (ZG07Cr19Ni9) — SAC (2016)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.