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Stainless Steel 2304 vs S31200

Stainless Steel · grade comparison

Stainless Steel 2304 and S31200 are both stainless steel grades. S31200 is the stronger of the two: yield strength 530 MPa (76.9 ksi) against 460 MPa (66.7 ksi) for 2304, about 15% more; tensile strength follows at 770 MPa (112 ksi) vs 680 MPa (98.6 ksi). S31200 is harder — 24 HRC against 22 HRC for 2304 — which matters for wear surfaces and threads.

S31200Choose it when strength drives the design, or when surface hardness matters.

2304 vs S31200: properties

2304S31200

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Bulk Modulus

150 GPa21.8 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

680 MPa98.6 ksi
770 MPa112 ksi

Yield Strength (0.2% offset)

460 MPa66.7 ksi
530 MPa76.9 ksi

Elongation at Break

30%
32%

Reduction in Area

55%
60%

Compressive Strength

470 MPa68.2 ksi
530 MPa76.9 ksi

Shear Strength

420 MPa60.9 ksi
470 MPa68.2 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
340 MPa49.3 ksi

Fracture Toughness (K_IC)

120 MPa·√m109 ksi·√in
150 MPa·√m137 ksi·√in

Charpy V-Notch Impact (RT)

220 J162 ft·lbf
180 J133 ft·lbf

Hardness, Rockwell B

99 HRB
100 HRB

Hardness, Rockwell C

22 HRC
24 HRC

Hardness, Vickers

250 HV
255 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 77 GPa11.2 Msi · Poisson's Ratio 0.3 · Hardness, Brinell 240 HB

Physical

Density and transition temperatures.

Density

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

Same in both: Melting Point (Solidus) 1,385°C2,525 °F · Liquidus Temperature 1,445°C2,633 °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

Latent Heat of Fusion

275 J/g118 BTU/lb
270 J/g116 BTU/lb

Same in both: 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

74 / 100
78 / 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 Rating (AISI 1212 = 100 %)

40%
25%

Weldability

72 / 100
70 / 100

Formability (cold)

55 / 100
50 / 100

Same in both: Machinability 35 / 100 · Castability 45 / 100 · Brazeability / Solderability 40 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

46 MJ/kg19,776 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

3.8 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

100 L/kg12 gal/lb
120 L/kg14.4 gal/lb

Typical Recycled Content

70%
65%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

88 kN·m/kg
99 kN·m/kg

Specific Stiffness (E / density)

25.8 MN·m/kg
25.6 MN·m/kg

Modulus of Resilience

529 kJ/m³
702 kJ/m³

Thermal Diffusivity

4.3 mm²/s
4.1 mm²/s

Thermal Shock Resistance Index

4
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 scaleS312002304

Manufacturing and finishing

Capability2304S31200
CNC machiningYes—
Sheet metalYes—
Default conditionSolution Annealed—
Relative cost$$$ Premium$$$ Premium
Min. machined wall0.8 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.

2304 vs S31200 — frequently asked

Is S31200 stronger than 2304?

Yes. S31200 has a typical yield strength of 530 MPa (76.9 ksi) against 460 MPa (66.7 ksi) for 2304 — about 15% more. Tensile strength is 770 MPa (112 ksi) vs 680 MPa (98.6 ksi).

Which is cheaper, 2304 or S31200?

Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.

When should I choose 2304 over S31200?

Pick S31200 when strength drives the design, or when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 2304 and S31200 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.