Stainless Steel CG12
ASTM CG12 · UNS J93001
CG12 (J93001) is a high chromium-nickel cast austenitic stainless steel, the casting analogue of 309, supplied solution annealed at 250 MPa yield, 520 MPa tensile strength, 45% elongation and 150 HB (80 HRB).
Reference datasheet — CG12 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
CG12 tempers and conditions
CG12 is supplied in 2 conditions, soft to hard. SA is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefault Solution annealed | Standard supply condition required by ASTM A743/A351; maximum corrosion resistance and ductility. | 250 | 520 | 45 | 150 HB | — |
Spheroidize annealed | Only for non-corrosive or purely structural service; carbides at grain boundaries lower ductility and corrosion resistance. | 265 | 500 | 25 | 170 HB | 2.2 % IACS |
What is CG12?
CG12 (J93001) is a high chromium-nickel cast austenitic stainless steel, the casting analogue of 309, supplied solution annealed at 250 MPa yield, 520 MPa tensile strength, 45% elongation and 150 HB (80 HRB). The high chromium gives a corrosion resistance score of 65 with service to 870 °C, so it is used for chemical process castings and valve components that also see heat. Machinability is roughly 45% of AISI 1212 and the alloy work-hardens readily. Where molybdenum-bearing pitting resistance is needed instead of chromium and temperature capability, CG8M is the nearer choice. CG12 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). CG12 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 91% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 193 GPa (28 Msi).
What is CG12 used for?
- Chemical process castings
- Corrosion-resistant valve components
- Pump casings for hot chemical service
- Furnace and heat-treat fixture castings
- Pipe fittings and elbows
- High-temperature flanges and bodies
Advantages
- High service temperature — 870°C (1,598 °F), better than 83% of stainless steel grades
- Low embodied carbon — 3.6 kg CO₂/kg, better than 83% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Low strength — 250 MPa (36.3 ksi), worse than 91% of stainless steel grades
- Hard to polish — 55/100, worse than 89% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
CG12 properties
Typical room-temperature values for CG12-SA; bars are the position among stainless steel grades.
Physical3
CG12 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
CG12 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 91% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
CG12 is rated for continuous service to 870°C (1,598 °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
CG12 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 56% of stainless steel grades.
Sustainability4
Producing a kilogram of CG12 takes about 53 MJ of energy and emits 3.6 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 75%.
Manufacturability8
CG12's machinability is fair (35/100, better than 51% of stainless steel grades); weldability very good (70/100); 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. CG12 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CG12
Is CG12 easy to machine?
Machine like 309: rigid setups, sharp positive-rake carbide, heavy constant feed and flood coolant to avoid work-hardened glaze; expect ~45% of AISI 1212 rates.
Can CG12 be welded?
Readily welded with ER309/E309 filler by GTAW/SMAW; keep interpass below ~150 °C and re-solution anneal repaired pressure castings to restore corrosion resistance.
Can CG12 be formed, bent or molded?
Sand or investment cast with generous risering for the wide freezing range and ~2.2% shrinkage; not a cold-forming grade.
CG12 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 |
|---|---|---|
| Cmax per ASTM A743 | ≤ 0.12 | 0.08 |
| Mn | ≤ 1.5 | 1 |
| Si | ≤ 2 | 1.2 |
| P | ≤ 0.04 | |
| S | ≤ 0.04 | |
| Cr | 20 – 23 | 21.5 |
| Ni | 10 – 13 | 11.5 |
| Moresidual only; not intentionally added | ≤ 0.5 | |
| Fe | balance |
What surface finishes work on CG12?
Grit blast, pickle (HNO3-HF) and passivate per ASTM A967 or electropolish; anodizing does not apply.
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 CG12 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J93001
How much does CG12 cost?
CG12 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.
CG12 — frequently asked
What is CG12 used for?
CG12 is typically used for chemical process castings, corrosion-resistant valve components, pump casings for hot chemical service, furnace and heat-treat fixture castings, pipe fittings and elbows and high-temperature flanges and bodies. In short: cast 309-type composition; high-chromium corrosion and heat; wide freezing range casting.
What is the yield strength of CG12?
CG12 has a typical yield strength of 250 MPa (36.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 91% of stainless steel grades. Strength varies by condition: see the 2 listed tempers.
Is CG12 easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of stainless steel grades). Machine like 309: rigid setups, sharp positive-rake carbide, heavy constant feed and flood coolant to avoid work-hardened glaze; expect ~45% of AISI 1212 rates.
Can CG12 be welded?
Yes — weldability is rated very good (70/100). Readily welded with ER309/E309 filler by GTAW/SMAW; keep interpass below ~150 °C and re-solution anneal repaired pressure castings to restore corrosion resistance.
What surface finishes work on CG12?
Grit blast, pickle (HNO3-HF) and passivate per ASTM A967 or electropolish; anodizing does not apply.
Can CG12 be formed, bent or molded?
Sand or investment cast with generous risering for the wide freezing range and ~2.2% shrinkage; not a cold-forming grade.
What is the maximum service temperature of CG12?
CG12 is rated for continuous use to about 870°C (1,598 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CG12-SA and CG12-AC?
SA is the default condition — standard supply condition required by ASTM A743/A351; maximum corrosion resistance and ductility. AC: only for non-corrosive or purely structural service; carbides at grain boundaries lower ductility and corrosion resistance. Yield strength is 250 MPa in SA versus 265 MPa in AC.
How much does CG12 cost?
CG12 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)
- ASTM A351/A351M — Castings, Austenitic, for Pressure-Containing Parts — ASTM International (2018)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- 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.