Stainless Steel 255-SD50 vs 255 Solution Annealed
Stainless Steel · 255 temper comparison
255-SD50 and 255 Solution Annealed are two conditions of the same stainless steel grade, 255: SD50 (ferralium 255-SD50) versus Solution Annealed. The chemistry is identical, so every difference below comes from the condition. 255-SD50 is the stronger of the two: yield strength 660 MPa (95.7 ksi) against 610 MPa (88.5 ksi) for 255 Solution Annealed, about 8% more; tensile strength follows at 880 MPa (128 ksi) vs 830 MPa (120 ksi). In exchange, 255 Solution Annealed is the more ductile: elongation 28% versus 25% for 255-SD50, and 255-SD50 is harder (280 HB vs 265 HB).
255-SD50Choose it when strength drives the design.
255 Solution AnnealedChoose it when the part is bent, formed or impact-loaded.
255-SD50 vs 255 Solution Annealed: 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 C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 79 GPa11.5 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.3
Physical
Density and transition temperatures.
Same in both: Density 7.81 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 13.5 W/m·K7.8 BTU/hr·ft·°F · Specific Heat Capacity 480 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 13 µm/m·K7.2 µin/in·°F · Max Service Temperature (continuous) 300°C572 °F · Min Service Temperature -50°C-58 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.2 % IACS · Electrical Resistivity 8×10⁻⁷ Ω·m31.5 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.15 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 55 / 100 · Brazeability / Solderability 40 / 100 · Polishability 75 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 85 MJ/kg36,543 BTU/lb · Embodied Carbon (primary production) 5.6 kg CO₂/kg · Embodied Water 200 L/kg24 gal/lb · Typical Recycled Content 50%
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.
255-SD50 vs 255 Solution Annealed — frequently asked
Is 255-SD50 stronger than 255 Solution Annealed?
Yes. 255-SD50 has a typical yield strength of 660 MPa (95.7 ksi) against 610 MPa (88.5 ksi) for 255 Solution Annealed — about 8% more. Tensile strength is 880 MPa (128 ksi) vs 830 MPa (120 ksi).
Which condition does FabDigit quote by default, SD50 or Solution Annealed?
Solution Annealed is the default 255 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.
When should I choose 255-SD50 over 255 Solution Annealed?
Pick 255-SD50 when strength drives the design. Pick 255 Solution Annealed when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 255-SD50 and 255 Solution Annealed 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.