Stainless Steel 316C12
EN 316C12 · ASTM CF8M
316C12 is the British Standard cast designation equivalent to CF8M, a 19Cr-9Ni-2Mo austenitic stainless steel available solution-treated, as-cast, ST+HIP or centrifugally cast and solution-treated.
Reference datasheet — 316C12 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
316C12 tempers and conditions
316C12 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 | The standard supply condition for all pressure-retaining and corrosion-service castings; carbides dissolved for maximum intergranular corrosion resistance. | 260 | 530 | 45 | 155 HB | — |
Hot isostatically pressed then solution treated | Choose for fatigue- or leak-critical valve/pump castings where internal microporosity must be closed. | 270 | 550 | 50 | 155 HB | 2.3 % IACS |
Spheroidize annealed | Only for non-critical, non-corrosive or purely mechanical castings — grain-boundary carbides leave the part sensitized. | 275 | 540 | 30 | 170 HB | 2.2 % IACS |
Supply forms, finishes and certifications
Ways 316C12 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
CC-ST | Centrifugally cast, solution treated | Surface finish |
What is 316C12?
316C12 is the British Standard cast designation equivalent to CF8M, a 19Cr-9Ni-2Mo austenitic stainless steel available solution-treated, as-cast, ST+HIP or centrifugally cast and solution-treated. The molybdenum addition lifts chloride pitting resistance well above 304C15 (corrosion score 76 versus 62), which is why it dominates seawater and chemical process valve and pump castings; default values are 260 MPa yield, 530 MPa tensile, 45 % elongation and 155 HB (81 HRB). Maximum service temperature on file is 550 °C, lower than cast 304, and the unstabilized carbon level means major repair welds may need re-solution treatment. Use 316C16 (CF3M) where parts must serve as-welded. 316C12 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,390°C (2,534 °F). 316C12 has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 193 GPa (28 Msi).
What is 316C12 used for?
- valve bodies
- pump casings
- seawater fittings
- chemical process castings
Advantages
- Good corrosion resistance — 76/100, better than 80% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Low strength — 260 MPa (37.7 ksi), worse than 84% of stainless steel grades
- Limited formability — 25/100, worse than 78% of stainless steel grades
316C12 properties
Typical room-temperature values for 316C12-ST; bars are the position among stainless steel grades.
Physical3
316C12 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,390°C (2,534 °F).
Mechanical16
316C12 has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
316C12 is rated for continuous service to 550°C (1,022 °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
316C12 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (76/100), better than 80% of stainless steel grades.
Sustainability4
Producing a kilogram of 316C12 takes about 60 MJ of energy and emits 4.2 kg of CO₂ — more than 70% of stainless steel grades. Typical recycled content is 75%.
Manufacturability8
316C12's machinability is fair (35/100, better than 51% of stainless steel grades); weldability very good (72/100); 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. 316C12 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 316C12
Is 316C12 easy to machine?
Machine like wrought 316: rigid setup, sharp coated carbide, positive rake, heavy feed and 60–120 m/min to cut under the work-hardened skin, plus flood coolant; expect casting-skin sand/oxide on the first pass.
Can 316C12 be welded?
Readily welded with 316L (ER316L/E316L-16) filler using GTAW/SMAW, no preheat, interpass below 150 °C; re-solution treat after major repair welds if intergranular corrosion service is critical.
Can 316C12 be formed, bent or molded?
Sand, investment and centrifugal casting all suitable; allow ~2.0–2.3% shrinkage, use generous risering and chills because the alloy is mushy-freezing and prone to centreline shrinkage.
316C12 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 |
|---|---|---|
| CBS 3100 316C12 low-to-medium carbon cast grade | ≤ 0.07 | 0.05 |
| Si | ≤ 1.5 | 1 |
| Mn | ≤ 2 | 1 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.04 | 0.02 |
| Cr | 16.5 – 18.5 | 17.5 |
| Ni | 10 – 13 | 11 |
| Mogives the chloride pitting advantage over 304C15 | 2 – 3 | 2.5 |
| Febalance; ferrite content typically 8–20 FN | balance |
What surface finishes work on 316C12?
Passivate (ASTM A967 nitric or citric) or electropolish after machining; shot/bead blasting and pickling remove casting scale — never anodise, and avoid carbon-steel contamination on grinding tools.
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 316C12 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- CF8M
How much does 316C12 cost?
316C12 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.
316C12 — frequently asked
What is 316C12 used for?
316C12 is typically used for valve bodies, pump casings, seawater fittings and chemical process castings. In short: mo-bearing cast 316; better chloride pitting than 304C15; lower temp limit than CF8.
What is the yield strength of 316C12?
316C12 has a typical yield strength of 260 MPa (37.7 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 84% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 316C12 easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of stainless steel grades). Machine like wrought 316: rigid setup, sharp coated carbide, positive rake, heavy feed and 60–120 m/min to cut under the work-hardened skin, plus flood coolant; expect casting-skin sand/oxide on the first pass.
Can 316C12 be welded?
Yes — weldability is rated very good (72/100). Readily welded with 316L (ER316L/E316L-16) filler using GTAW/SMAW, no preheat, interpass below 150 °C; re-solution treat after major repair welds if intergranular corrosion service is critical.
What surface finishes work on 316C12?
Passivate (ASTM A967 nitric or citric) or electropolish after machining; shot/bead blasting and pickling remove casting scale — never anodise, and avoid carbon-steel contamination on grinding tools.
Can 316C12 be formed, bent or molded?
Sand, investment and centrifugal casting all suitable; allow ~2.0–2.3% shrinkage, use generous risering and chills because the alloy is mushy-freezing and prone to centreline shrinkage.
What is the maximum service temperature of 316C12?
316C12 is rated for continuous use to about 550°C (1,022 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 316C12-ST and 316C12-AC?
ST is the default condition — the standard supply condition for all pressure-retaining and corrosion-service castings; carbides dissolved for maximum intergranular corrosion resistance. AC: only for non-critical, non-corrosive or purely mechanical castings — grain-boundary carbides leave the part sensitized. Yield strength is 260 MPa in ST versus 275 MPa in AC.
How much does 316C12 cost?
316C12 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
- BS 3100 — Steel castings for general engineering purposes (grade 316C12) — BSI (1991)
- ASTM A351/A351M — Castings, Austenitic, for Pressure-Containing Parts (CF8M) — ASTM International (2018)
- EN 10283 — Corrosion resistant steel castings (1.4408 / GX5CrNiMo19-11-2) — CEN (2010)
- 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)
- SMM / 1688 stainless casting price levels (2025)
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.