Stainless Steel 654 SMO-CD vs 654 SMO FG-SA
Stainless Steel · 654 SMO temper comparison
654 SMO-CD and 654 SMO FG-SA are two conditions of the same stainless steel grade, 654 SMO: CD (cold drawn) versus FG-SA (forged + SA). The chemistry is identical, so every difference below comes from the condition. 654 SMO-CD is the stronger of the two: yield strength 650 MPa (94.3 ksi) against 470 MPa (68.2 ksi) for 654 SMO FG-SA, about 38% more; tensile strength follows at 900 MPa (131 ksi) vs 800 MPa (116 ksi). In exchange, 654 SMO FG-SA is the more ductile: elongation 45% versus 30% for 654 SMO-CD, and 654 SMO-CD is harder (265 HB vs 215 HB). 654 SMO FG-SA runs hotter in service (400°C vs 350°C continuous).
654 SMO-CDChoose it when strength drives the design.
654 SMO FG-SAChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
654 SMO-CD vs 654 SMO FG-SA: 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
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 190 GPa27.6 Msi · Shear Modulus 73 GPa10.6 Msi · Bulk Modulus 158 GPa22.9 Msi · Poisson's Ratio 0.3
Physical
Density and transition temperatures.
Same in both: Density 8 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,320°C2,408 °F · Liquidus Temperature 1,400°C2,552 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 8.6 W/m·K5 BTU/hr·ft·°F · Specific Heat Capacity 510 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 15.5 µm/m·K8.6 µin/in·°F · Latent Heat of Fusion 265 J/g114 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2 % IACS · Electrical Resistivity 8.5×10⁻⁷ Ω·m33.5 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.05 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: Brazeability / Solderability 40 / 100 · Polishability 80 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 85 MJ/kg36,543 BTU/lb · Embodied Carbon (primary production) 6.5 kg CO₂/kg · Embodied Water 210 L/kg25.2 gal/lb · Typical Recycled Content 40%
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.
654 SMO-CD vs 654 SMO FG-SA — frequently asked
Is 654 SMO-CD stronger than 654 SMO FG-SA?
Yes. 654 SMO-CD has a typical yield strength of 650 MPa (94.3 ksi) against 470 MPa (68.2 ksi) for 654 SMO FG-SA — about 38% more. Tensile strength is 900 MPa (131 ksi) vs 800 MPa (116 ksi).
Which condition does FabDigit quote by default, CD or FG-SA?
SA is the default 654 SMO condition in the FabDigit quote flow (neither CD nor FG-SA). 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, 654 SMO-CD or 654 SMO FG-SA?
654 SMO FG-SA. Its weldability rates good (60/100) against good (55/100) for 654 SMO-CD.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 654 SMO-CD and 654 SMO FG-SA 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.