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Stainless Steel 2205 vs S31100

Stainless Steel · grade comparison

Stainless Steel 2205 and S31100 are both stainless steel grades. 2205 is the stronger of the two: yield strength 540 MPa (78.3 ksi) against 500 MPa (72.5 ksi) for S31100, about 8% more. 2205 is harder — 255 HB against 240 HB for S31100 — which matters for wear surfaces and threads. On the shop floor, 2205 welds better (very good vs good) and S31100 sits in a lower cost tier (premium, $$$) than 2205 (specialty, $$$$$).

2205Choose it when strength drives the design, or when surface hardness matters.

S31100Choose it when cost is the deciding factor.

2205 vs S31100: properties

2205S31100

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

790 MPa115 ksi
760 MPa110 ksi

Yield Strength (0.2% offset)

540 MPa78.3 ksi
500 MPa72.5 ksi

Reduction in Area

60%
55%

Compressive Strength

540 MPa78.3 ksi
510 MPa74 ksi

Shear Strength

480 MPa69.6 ksi
470 MPa68.2 ksi

Fatigue Strength (Endurance Limit)

390 MPa56.6 ksi
320 MPa46.4 ksi

Fracture Toughness (K_IC)

120 MPa·√m109 ksi·√in
110 MPa·√m100 ksi·√in

Charpy V-Notch Impact (RT)

220 J162 ft·lbf
120 J88.5 ft·lbf

Hardness, Brinell

255 HB
240 HB

Hardness, Rockwell B

100 HRB
99 HRB

Hardness, Rockwell C

26 HRC
23 HRC

Hardness, Vickers

265 HV
255 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3 · Elongation at Break 30%

Physical

Density and transition temperatures.

Density

7.8 g/cm³0.28 lb/in³
7.75 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,385°C2,525 °F
1,400°C2,552 °F

Liquidus Temperature

1,445°C2,633 °F
1,450°C2,642 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

16 W/m·K9.2 BTU/hr·ft·°F
15.5 W/m·K9 BTU/hr·ft·°F

Specific Heat Capacity

470 J/kg·K0.11 BTU/lb·°F
480 J/kg·K0.11 BTU/lb·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
—

Same in both: 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

80 / 100
68 / 100

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

32 / 100
33 / 100

Weldability

78 / 100
62 / 100

Formability (cold)

55 / 100
48 / 100

Polishability

75 / 100
72 / 100

Castability

—
50 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 30% · Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

62 MJ/kg26,655 BTU/lb
53 MJ/kg22,786 BTU/lb

Embodied Water

130 L/kg15.6 gal/lb
180 L/kg21.6 gal/lb

Same in both: Embodied Carbon (primary production) 4.6 kg CO₂/kg · Typical Recycled Content 65%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

101 kN·m/kg
98 kN·m/kg

Specific Stiffness (E / density)

25.6 MN·m/kg
25.8 MN·m/kg

Modulus of Resilience

729 kJ/m³
625 kJ/m³

Thermal Diffusivity

4.4 mm²/s
4.2 mm²/s

Same in both: Thermal Shock Resistance Index 5

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.

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scale2205S31100

Manufacturing and finishing

Capability2205S31100
CNC machiningYes—
Sheet metalYes—
Default conditionSolution Annealed—
Relative cost$$$$$ Specialty$$$ Premium
Min. machined wall1 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
ElectropolishingYes—
HVOF CoatingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—
Passivation (Stainless Steel)Yes—

They share 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.

2205 vs S31100 — frequently asked

Is 2205 stronger than S31100?

Yes. 2205 has a typical yield strength of 540 MPa (78.3 ksi) against 500 MPa (72.5 ksi) for S31100 — about 8% more. Tensile strength is 790 MPa (115 ksi) vs 760 MPa (110 ksi).

Which is cheaper, 2205 or S31100?

S31100 is the lower-cost material: it sits in the premium tier ($$$) while 2205 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, 2205 or S31100?

2205. Its weldability rates very good (78/100) against good (62/100) for S31100.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 2205 and S31100 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.