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Stainless Steel S20431 3/4H vs S20431-FH

Stainless Steel · S20431 temper comparison

S20431 3/4H and S20431-FH are two conditions of the same stainless steel grade, S20431: 3/4H (three-quarter hard) versus FH (full hard). The chemistry is identical, so every difference below comes from the condition. S20431-FH is the stronger of the two: yield strength 1,130 MPa (164 ksi) against 1,010 MPa (146 ksi) for S20431 3/4H, about 12% more; tensile strength follows at 1,380 MPa (200 ksi) vs 1,270 MPa (184 ksi). In exchange, S20431 3/4H is the more ductile: elongation 13% versus 9% for S20431-FH, and S20431-FH is harder (380 HB vs 345 HB).

S20431 3/4HChoose it when the part is bent, formed or impact-loaded.

S20431-FHChoose it when strength drives the design.

S20431 3/4H vs S20431-FH: properties

S20431 3/4HS20431-FH

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,270 MPa184 ksi
1,380 MPa200 ksi

Yield Strength (0.2% offset)

1,010 MPa146 ksi
1,130 MPa164 ksi

Elongation at Break

13%
9%

Reduction in Area

45%
40%

Shear Strength

760 MPa110 ksi
830 MPa120 ksi

Fatigue Strength (Endurance Limit)

490 MPa71.1 ksi
530 MPa76.9 ksi

Fracture Toughness (K_IC)

95 MPa·√m86.5 ksi·√in
80 MPa·√m72.8 ksi·√in

Charpy V-Notch Impact (RT)

42 J31 ft·lbf
28 J20.7 ft·lbf

Hardness, Brinell

345 HB
380 HB

Hardness, Vickers

370 HV
410 HV

Same in both: Elastic (Young's) Modulus 197 GPa28.6 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 85 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.8 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.

Max Service Temperature (continuous)

300°C572 °F
290°C554 °F

Same in both: Thermal Conductivity 16.2 W/m·K9.4 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 15.7 µm/m·K8.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

7×10⁻⁷ Ω·m27.6 µΩ·in
7.1×10⁻⁷ Ω·m28 µΩ·in

Same in both: Electrical Conductivity 2.4 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

46 / 100
45 / 100

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

35 / 100
34 / 100

Weldability

48 / 100
45 / 100

Formability (cold)

30 / 100
18 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 45% · Brazeability / Solderability 60 / 100 · Polishability 80 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 45 MJ/kg19,347 BTU/lb · Embodied Carbon (primary production) 3.8 kg CO₂/kg · Embodied Water 95 L/kg11.4 gal/lb · Typical Recycled Content 55%

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 scaleS20431

S20431 3/4H vs S20431-FH — frequently asked

Is S20431-FH stronger than S20431 3/4H?

Yes. S20431-FH has a typical yield strength of 1,130 MPa (164 ksi) against 1,010 MPa (146 ksi) for S20431 3/4H — about 12% more. Tensile strength is 1,380 MPa (200 ksi) vs 1,270 MPa (184 ksi).

Which condition does FabDigit quote by default, 3/4H or FH?

Annealed is the default S20431 condition in the FabDigit quote flow (neither 3/4H nor FH). 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 S20431 3/4H over S20431-FH?

Pick S20431 3/4H when the part is bent, formed or impact-loaded. Pick S20431-FH when strength drives the design.

Ready to make it?

Upload a CAD file and FabDigit prices the part in S20431 3/4H and S20431-FH 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.