Stainless Steel CF3MN
ASTM CF3MN · UNS J92804
CF3MN (UNS J92804) is a nitrogen-enhanced version of CF3M, a low-carbon molybdenum-alloyed cast austenitic stainless in which interstitial nitrogen raises strength without reintroducing the sensitization risk of higher-carbon grades.
Reference datasheet — CF3MN 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
CF3MN tempers and conditions
CF3MN is supplied in 3 conditions, soft to hard. SA 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 |
|---|---|---|---|---|---|---|
SADefault Solution annealed ≥1040 °C, water quenched | Standard supply condition for all pressure-containing CF3MN castings per ASTM A351/A743. | 290 | 550 | 45 | 170 HB | — |
hot isostatically pressed then solution annealed | Pick for thick-section or fatigue/impact-critical castings where shrinkage microporosity must be closed. | 295 | 565 | 50 | 170 HB | 2.2 % IACS |
Spheroidize annealed | Only for non-pressure, non-corrosive structural parts — not acceptable under ASTM A351/A743 for service castings. | 300 | 530 | 25 | 180 HB | 2.2 % IACS |
Supply forms, finishes and certifications
Ways CF3MN is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
DUAL-CF3M | Dual-certified CF3M / CF3MN, solution annealed | Certification |
What is CF3MN?
CF3MN (UNS J92804) is a nitrogen-enhanced version of CF3M, a low-carbon molybdenum-alloyed cast austenitic stainless in which interstitial nitrogen raises strength without reintroducing the sensitization risk of higher-carbon grades. It is chosen for high-strength pressure castings and chemical or marine valve bodies, supplied solution-annealed, HIP-SA, as-cast or dual-certified with CF3M. Typical solution-annealed values are 290 MPa yield, 550 MPa tensile, 45 % elongation, 170 HB (87 HRB) and service to 500 °C. Machining is harder than CF3M, which remains the fallback where the extra strength is not needed. CF3MN has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,385°C (2,525 °F). CF3MN has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi).
What is CF3MN used for?
- High-strength pressure castings
- Chemical process valves
- Marine components
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 formability — 25/100, worse than 78% of stainless steel grades
CF3MN properties
Typical room-temperature values for CF3MN-SA; bars are the position among stainless steel grades.
Physical3
CF3MN has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,385°C (2,525 °F).
Mechanical16
CF3MN has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
CF3MN is rated for continuous service to 500°C (932 °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 µm/m·K (8.89 µin/in·°F).
Electrical3
CF3MN conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 73% of stainless steel grades.
Sustainability4
Producing a kilogram of CF3MN 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
CF3MN's machinability is fair (35/100, better than 51% of stainless steel grades); weldability excellent (85/100); formability poor (25/100).
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. CF3MN is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CF3MN
Is CF3MN easy to machine?
Gummy and work-hardening from the nitrogen — use rigid setups, sharp positive-rake carbide, heavy positive feed and flood coolant; expect ~35% of 1212 speeds and interrupted cuts through the cast skin.
Can CF3MN be welded?
Readily welded by GTAW/GMAW/SMAW with ER316L or higher-Mo 316LMn/309LMo filler; no pre- or post-weld heat treatment required for corrosion, keep interpass below ~150 °C and heat input low to limit sigma/ferrite issues.
Can CF3MN be formed, bent or molded?
Sand or investment cast with generous risers on heavy sections; austenitic solidification shrinkage ~5–6% requires directional feeding, then solution treat above 1040 °C and water quench.
CF3MN 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 intergranular resistance | ≤ 0.03 | 0.02 |
| Mn | ≤ 1.5 | 1 |
| Si | ≤ 1.5 | 1 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.04 | 0.02 |
| Cr | 17 – 21 | 19 |
| Ni | 9 – 13 | 11 |
| Mo | 2 – 3 | 2.5 |
| Nsolid-solution strengthening, defines the 'N' suffix | 0.1 – 0.2 | 0.15 |
| Fe | balance |
What surface finishes work on CF3MN?
Pickle and passivate (ASTM A967) or electropolish after grinding; anodizing is not applicable, and shot blasting should use stainless or ceramic media to avoid iron contamination.
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 CF3MN in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J92804
- Also called
- Cast 316LN
How much does CF3MN cost?
CF3MN 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.
CF3MN — frequently asked
What is CF3MN used for?
CF3MN is typically used for high-strength pressure castings, chemical process valves and marine components. In short: stronger cast 316L; nitrogen-strengthened CF3M; low-carbon weldability retained.
What is the yield strength of CF3MN?
CF3MN has a typical yield strength of 290 MPa (42.1 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 72% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is CF3MN easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of stainless steel grades). Gummy and work-hardening from the nitrogen — use rigid setups, sharp positive-rake carbide, heavy positive feed and flood coolant; expect ~35% of 1212 speeds and interrupted cuts through the cast skin.
Can CF3MN be welded?
Yes — weldability is rated excellent (85/100). Readily welded by GTAW/GMAW/SMAW with ER316L or higher-Mo 316LMn/309LMo filler; no pre- or post-weld heat treatment required for corrosion, keep interpass below ~150 °C and heat input low to limit sigma/ferrite issues.
What surface finishes work on CF3MN?
Pickle and passivate (ASTM A967) or electropolish after grinding; anodizing is not applicable, and shot blasting should use stainless or ceramic media to avoid iron contamination.
Can CF3MN be formed, bent or molded?
Sand or investment cast with generous risers on heavy sections; austenitic solidification shrinkage ~5–6% requires directional feeding, then solution treat above 1040 °C and water quench.
What is the maximum service temperature of CF3MN?
CF3MN is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CF3MN-SA and CF3MN-AC?
SA is the default condition — standard supply condition for all pressure-containing CF3MN castings per ASTM A351/A743. AC: only for non-pressure, non-corrosive structural parts — not acceptable under ASTM A351/A743 for service castings. Yield strength is 290 MPa in SA versus 300 MPa in AC.
How much does CF3MN cost?
CF3MN 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 A743/A743M — Castings, Iron-Chromium-Nickel, Corrosion Resistant, for General Application — ASTM International (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (cast corrosion-resistant 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; 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.