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Stainless Steel ER308 vs ER308H

Stainless Steel · grade comparison

Stainless Steel ER308 and ER308H are both stainless steel grades. Both yield at about 400 MPa — strength does not separate them. ER308 is harder — 185 HB against 175 HB for ER308H — which matters for wear surfaces and threads.

ER308Choose it when surface hardness matters.

ER308 vs ER308H: properties

ER308ER308H

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

195 GPa28.3 Msi
196 GPa28.4 Msi

Bulk Modulus

145 GPa21 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

600 MPa87 ksi
590 MPa85.6 ksi

Yield Strength (0.2% offset)

400 MPa58 ksi
415 MPa60.2 ksi

Elongation at Break

40%
38%

Compressive Strength

400 MPa58 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

240 MPa34.8 ksi
230 MPa33.4 ksi

Fracture Toughness (K_IC)

150 MPa·√m137 ksi·√in
180 MPa·√m164 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
85 J62.7 ft·lbf

Hardness, Brinell

185 HB
175 HB

Hardness, Rockwell B

90 HRB
87 HRB

Hardness, Vickers

195 HV
185 HV

Same in both: Shear Modulus 77 GPa11.2 Msi · Reduction in Area 55% · Shear Strength 400 MPa58 ksi

Physical

Density and transition temperatures.

Same in both: Density 7.9 g/cm³0.29 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.

Thermal Conductivity

15.5 W/m·K9 BTU/hr·ft·°F
16.2 W/m·K9.4 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

16.9 µm/m·K9.4 µin/in·°F
16.5 µm/m·K9.2 µin/in·°F

Latent Heat of Fusion

280 J/g120 BTU/lb
285 J/g123 BTU/lb

Max Service Temperature (continuous)

760°C1,400 °F
800°C1,472 °F

Same in both: Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

7.4×10⁻⁷ Ω·m29.1 µΩ·in
7.2×10⁻⁷ Ω·m28.3 µΩ·in

Same in both: Electrical Conductivity 2.4 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.08 V
-0.05 V

Corrosion Resistance

65 / 100
58 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability Rating (AISI 1212 = 100 %)

45%
40%

Weldability

95 / 100
88 / 100

Polishability

70 / 100
65 / 100

Same in both: Machinability 38 / 100 · Formability (cold) 55 / 100 · Brazeability / Solderability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

57 MJ/kg24,506 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

5 kg CO₂/kg
4.5 kg CO₂/kg

Typical Recycled Content

45%
60%

Same in both: Embodied Water 130 L/kg15.6 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

76 kN·m/kg
75 kN·m/kg

Specific Stiffness (E / density)

24.7 MN·m/kg
24.8 MN·m/kg

Modulus of Resilience

410 kJ/m³
439 kJ/m³

Thermal Diffusivity

3.9 mm²/s
4.1 mm²/s

Same in both: Thermal Shock Resistance Index 3

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 scaleER308ER308H

Manufacturing and finishing

CapabilityER308ER308H
Default condition——
Relative cost$$$ Premium$$$ Premium
Min. machined wall——
Best machined surface——

Both take the same 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.

ER308 vs ER308H — frequently asked

What is the difference between ER308 and ER308H?

Stainless Steel ER308 and ER308H are both stainless steel grades. Both yield at about 400 MPa — strength does not separate them. ER308 is harder — 185 HB against 175 HB for ER308H — which matters for wear surfaces and threads.

Which is cheaper, ER308 or ER308H?

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.

Which welds better, ER308 or ER308H?

ER308. Its weldability rates excellent (95/100) against excellent (88/100) for ER308H.

Ready to make it?

Upload a CAD file and FabDigit prices the part in ER308 and ER308H 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.