Stainless Steel CF20
ASTM CF20 · UNS J92602 · JIS SCS12
CF20 (UNS J92602, SCS12) is a higher-carbon cast austenitic chromium-nickel stainless of the CF family, essentially CF8 with carbon at about 0.20 % for a modest strength and hardness gain.
Reference datasheet — CF20 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 ST condition
CF20 tempers and conditions
CF20 is supplied in 3 conditions, soft to hard. ST is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
STDefault Solution annealed | Standard supply condition: carbides dissolved and quenched in for maximum ductility and corrosion resistance. | 255 | 530 | 38 | 156 HB | — |
ST | Choose for cylindrical pump sleeves/liners where centrifugal soundness gives slightly higher and more consistent properties. | 270 | 560 | 40 | 160 HB | 2.4 % IACS |
Spheroidize annealed | Cheapest condition for non-critical, low-corrosivity parts; interdendritic carbides raise hardness but cut ductility and intergranular corrosion resistance. | 275 | 520 | 22 | 175 HB | 2.4 % IACS |
What is CF20?
CF20 (UNS J92602, SCS12) is a higher-carbon cast austenitic chromium-nickel stainless of the CF family, essentially CF8 with carbon at about 0.20 % for a modest strength and hardness gain. It is supplied as sand, investment and centrifugal castings for general corrosion-resistant hardware in the solution-treated or as-cast condition. Solution-treated properties are about 255 MPa yield, 530 MPa tensile, 38 % elongation and 156 HB (82 HRB), with service to 700 °C. The higher carbon sensitizes readily, so welded pressure parts need re-solution treatment; CF8 or CF3 are the alternatives for welded corrosion service. CF20 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). CF20 has a yield strength of 255 MPa (37 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 87% of stainless steel grades. Elongation at break is 38% and the elastic modulus is 193 GPa (28 Msi).
What is CF20 used for?
- General purpose valve and pump castings
- Fittings
- Decorative hardware
Limitations
- Low strength — 255 MPa (37 ksi), worse than 87% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
CF20 properties
Typical room-temperature values for CF20-ST; bars are the position among stainless steel grades.
Physical3
CF20 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
CF20 has a yield strength of 255 MPa (37 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 87% of stainless steel grades. Elongation at break is 38% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
CF20 is rated for continuous service to 700°C (1,292 °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 17.2 µm/m·K (9.56 µin/in·°F).
Electrical3
CF20 conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (63/100), better than 53% of stainless steel grades.
Sustainability4
Producing a kilogram of CF20 takes about 53 MJ of energy and emits 4.6 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 80%.
Manufacturability8
CF20's machinability is fair (38/100, better than 63% of stainless steel grades); weldability good (55/100); formability poor (20/100).
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. CF20 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CF20
Is CF20 easy to machine?
Work-hardens rapidly — use rigid setups, sharp positive-rake carbide, heavy positive feed and flood coolant; avoid dwelling.
Can CF20 be welded?
Weldable with 308/308L filler (GTAW/SMAW), but the 0.20 %C matrix sensitizes readily; re-solution treat welded pressure parts or accept intergranular risk.
Can CF20 be formed, bent or molded?
Sand or investment casting grade with good fluidity; allow ~2.0–2.5 % shrinkage and generous risering because of the wide freezing range.
CF20 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 |
|---|---|---|
| Chigh-carbon variant of CF8 | ≤ 0.2 | 0.15 |
| Mn | ≤ 1.5 | 1 |
| Si | ≤ 2 | 1.3 |
| P | ≤ 0.04 | |
| S | ≤ 0.04 | |
| Cr | 18 – 21 | 19.5 |
| Ni | 8 – 11 | 9.5 |
| Fe | balance |
What surface finishes work on CF20?
Pickle and passivate per ASTM A967 or electropolish; shot blasting alone leaves an oxide skin that degrades corrosion performance.
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 CF20 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J92602
- JIS
- SCS12
- Also called
- Cast 302
How much does CF20 cost?
CF20 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.
CF20 — frequently asked
What is CF20 used for?
CF20 is typically used for general purpose valve and pump castings, fittings and decorative hardware. In short: higher-carbon cast CF8; general corrosion-resistant castings; sensitizes when welded.
What is the yield strength of CF20?
CF20 has a typical yield strength of 255 MPa (37 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 87% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is CF20 easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Work-hardens rapidly — use rigid setups, sharp positive-rake carbide, heavy positive feed and flood coolant; avoid dwelling.
Can CF20 be welded?
Yes — weldability is rated good (55/100). Weldable with 308/308L filler (GTAW/SMAW), but the 0.20 %C matrix sensitizes readily; re-solution treat welded pressure parts or accept intergranular risk.
What surface finishes work on CF20?
Pickle and passivate per ASTM A967 or electropolish; shot blasting alone leaves an oxide skin that degrades corrosion performance.
Can CF20 be formed, bent or molded?
Sand or investment casting grade with good fluidity; allow ~2.0–2.5 % shrinkage and generous risering because of the wide freezing range.
What is the maximum service temperature of CF20?
CF20 is rated for continuous use to about 700°C (1,292 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CF20-ST and CF20-AC?
ST is the default condition — standard supply condition: carbides dissolved and quenched in for maximum ductility and corrosion resistance. AC: cheapest condition for non-critical, low-corrosivity parts; interdendritic carbides raise hardness but cut ductility and intergranular corrosion resistance. Yield strength is 255 MPa in ST versus 275 MPa in AC.
How much does CF20 cost?
CF20 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 A743/A743M — Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application — ASTM International (2019)
- JIS G 5121 — Corrosion-resistant cast steels (SCS12) — JSA (2003)
- Steel Castings Handbook, 6th ed. — Steel Founders' Society of America / ASM (1995)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
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.