Steel E71T-8 vs ER70S-3
Steel · grade comparison
Steel E71T-8 and ER70S-3 are both steel grades. Both yield at about 460 MPa — strength does not separate them. E71T-8 is harder — 170 HB against 160 HB for ER70S-3 — which matters for wear surfaces and threads. On the shop floor, ER70S-3 forms better (very good vs good) and ER70S-3 sits in a lower cost tier (budget, $) than E71T-8 (standard, $$).
E71T-8Choose it when surface hardness matters.
ER70S-3Choose it when cost is the deciding factor.
E71T-8 vs ER70S-3: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all 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 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.
Elongation at Break
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Compressive Strength
Fracture Toughness (K_IC)
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 79 GPa11.5 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Tensile Strength (Ultimate) 550 MPa79.8 ksi · Yield Strength (0.2% offset) 460 MPa66.7 ksi
Physical
Density and transition temperatures.
Melting Point (Solidus)
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Liquidus Temperature 1,520°C2,768 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Min Service Temperature
Same in both: Thermal Conductivity 48 W/m·K27.7 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Max Service Temperature (continuous) 400°C752 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 10 % IACS · Electrical Resistivity 1.7×10⁻⁷ Ω·m6.69 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.65 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Castability
Same in both: Machinability Rating (AISI 1212 = 100 %) 60%
Sustainability
Primary-production footprint per kilogram.
Typical Recycled Content
Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.4 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb
Common Calculations
Ratios derived from the values above.
Thermal Shock Resistance Index
Same in both: Specific Strength (UTS / density) 70 kN·m/kg · Specific Stiffness (E / density) 26.1 MN·m/kg · Modulus of Resilience 516 kJ/m³ · Thermal Diffusivity 13 mm²/s
Strength versus weight
Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | E71T-8 | ER70S-3 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $ Budget |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
E71T-8 vs ER70S-3 — frequently asked
What is the difference between E71T-8 and ER70S-3?
Steel E71T-8 and ER70S-3 are both steel grades. Both yield at about 460 MPa — strength does not separate them. E71T-8 is harder — 170 HB against 160 HB for ER70S-3 — which matters for wear surfaces and threads.
Which is cheaper, E71T-8 or ER70S-3?
ER70S-3 is the lower-cost material: it sits in the budget tier ($) while E71T-8 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
When should I choose E71T-8 over ER70S-3?
Pick E71T-8 when surface hardness matters. Pick ER70S-3 when cost is the deciding factor.
Ready to make it?
Upload a CAD file and FabDigit prices the part in E71T-8 and ER70S-3 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.