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Steel ER70S-3 vs ER80S-Ni3

Steel · grade comparison

Steel ER70S-3 and ER80S-Ni3 are both steel grades. ER80S-Ni3 is the stronger of the two: yield strength 510 MPa (74 ksi) against 460 MPa (66.7 ksi) for ER70S-3, about 11% more; tensile strength follows at 600 MPa (87 ksi) vs 550 MPa (79.8 ksi). ER80S-Ni3 is harder — 190 HB against 160 HB for ER70S-3 — which matters for wear surfaces and threads. ER70S-3 runs hotter in service (400°C vs 350°C continuous) and ER70S-3 conducts heat better (48 W/m·K vs 38 W/m·K). On the shop floor, ER70S-3 forms better (very good vs good) and ER70S-3 sits in a lower cost tier (budget, $) than ER80S-Ni3 (premium, $$$).

ER70S-3Choose it when the part sees heat, or when cost is the deciding factor.

ER80S-Ni3Choose it when strength drives the design, or when surface hardness matters.

ER70S-3 vs ER80S-Ni3: properties

ER70S-3ER80S-Ni3

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

550 MPa79.8 ksi
600 MPa87 ksi

Yield Strength (0.2% offset)

460 MPa66.7 ksi
510 MPa74 ksi

Elongation at Break

28%
26%

Compressive Strength

460 MPa66.7 ksi
—

Shear Strength

330 MPa47.9 ksi
380 MPa55.1 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
130 MPa·√m118 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
130 J95.9 ft·lbf

Hardness, Brinell

160 HB
190 HB

Hardness, Rockwell B

84 HRB
91 HRB

Hardness, Vickers

168 HV
—

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 · Reduction in Area 65%

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,470°C2,678 °F
1,450°C2,642 °F

Liquidus Temperature

1,520°C2,768 °F
1,500°C2,732 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³

Thermal

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

Thermal Conductivity

48 W/m·K27.7 BTU/hr·ft·°F
38 W/m·K22 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

12 µm/m·K6.7 µin/in·°F
11.8 µm/m·K6.6 µin/in·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
270 J/g116 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
350°C662 °F

Min Service Temperature

-30°C-22 °F
-101°C-150 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
7.2 % IACS

Electrical Resistivity

1.7×10⁻⁷ Ω·m6.69 µΩ·in
2.4×10⁻⁷ Ω·m9.45 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.65 V
-0.62 V

Corrosion Resistance

10 / 100
14 / 100

Manufacturability

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

Machinability

58 / 100
52 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
58%

Weldability

95 / 100
88 / 100

Formability (cold)

80 / 100
55 / 100

Castability

70 / 100
—

Brazeability / Solderability

70 / 100
60 / 100

Same in both: Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

60 L/kg7.2 gal/lb
55 L/kg6.6 gal/lb

Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.4 kg CO₂/kg · Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

70 kN·m/kg
76 kN·m/kg

Modulus of Resilience

516 kJ/m³
634 kJ/m³

Thermal Diffusivity

13 mm²/s
10.3 mm²/s

Thermal Shock Resistance Index

11
9

Same in both: Specific Stiffness (E / density) 26.1 MN·m/kg

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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleER70S-3ER80S-Ni3

Manufacturing and finishing

CapabilityER70S-3ER80S-Ni3
Default condition——
Relative cost$ Budget$$$ Premium
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.

ER70S-3 vs ER80S-Ni3 — frequently asked

Is ER80S-Ni3 stronger than ER70S-3?

Yes. ER80S-Ni3 has a typical yield strength of 510 MPa (74 ksi) against 460 MPa (66.7 ksi) for ER70S-3 — about 11% more. Tensile strength is 600 MPa (87 ksi) vs 550 MPa (79.8 ksi).

Which is cheaper, ER70S-3 or ER80S-Ni3?

ER70S-3 is the lower-cost material: it sits in the budget tier ($) while ER80S-Ni3 is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, ER70S-3 or ER80S-Ni3?

ER70S-3. Its machinability rates good (58/100) against fair (52/100) for ER80S-Ni3; for welding the order is ER70S-3 first (excellent, 95/100) then ER80S-Ni3 (excellent, 88/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in ER70S-3 and ER80S-Ni3 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.