Stainless Steel 316C12-AC vs 316C12-ST
Stainless Steel · 316C12 temper comparison
316C12-AC and 316C12-ST are two conditions of the same stainless steel grade, 316C12: AC (spheroidize annealed) versus ST (solution annealed). The chemistry is identical, so every difference below comes from the condition. 316C12-AC is the stronger of the two: yield strength 275 MPa (39.9 ksi) against 260 MPa (37.7 ksi) for 316C12-ST, about 6% more. In exchange, 316C12-ST is the more ductile: elongation 45% versus 30% for 316C12-AC, and 316C12-AC is harder (170 HB vs 155 HB). 316C12-ST runs hotter in service (550°C vs 480°C continuous). On the shop floor, 316C12-ST welds better (very good vs good).
316C12-ACChoose it when strength drives the design.
316C12-STChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
316C12-AC vs 316C12-ST: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 193 GPa28 Msi · Shear Modulus 75 GPa10.9 Msi · Bulk Modulus 148 GPa21.5 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Same in both: Density 7.75 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,390°C2,534 °F · Liquidus Temperature 1,440°C2,624 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 14.5 W/m·K8.4 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 16 µm/m·K8.9 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -100°C-148 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.2 % IACS · Electrical Resistivity 7.8×10⁻⁷ Ω·m30.7 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.1 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 72 / 100 · Brazeability / Solderability 45 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 60 MJ/kg25,795 BTU/lb · Embodied Carbon (primary production) 4.2 kg CO₂/kg · Embodied Water 200 L/kg24 gal/lb · Typical Recycled Content 75%
Strength versus weight
Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
316C12-AC vs 316C12-ST — frequently asked
Is 316C12-AC stronger than 316C12-ST?
Yes. 316C12-AC has a typical yield strength of 275 MPa (39.9 ksi) against 260 MPa (37.7 ksi) for 316C12-ST — about 6% more. Tensile strength is 540 MPa (78.3 ksi) vs 530 MPa (76.9 ksi).
Which condition does FabDigit quote by default, AC or ST?
ST is the default 316C12 condition in the FabDigit quote flow. The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
Which welds better, 316C12-AC or 316C12-ST?
316C12-ST. Its weldability rates very good (72/100) against good (58/100) for 316C12-AC.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 316C12-AC and 316C12-ST side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.