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Steel ER100S-1 vs ER70S-2

Steel · grade comparison

Steel ER100S-1 and ER70S-2 are both steel grades. ER100S-1 is the stronger of the two: yield strength 690 MPa (100 ksi) against 450 MPa (65.3 ksi) for ER70S-2, about 53% more; tensile strength follows at 760 MPa (110 ksi) vs 560 MPa (81.2 ksi). In exchange, ER70S-2 is the more ductile: elongation 28% versus 21% for ER100S-1, and ER100S-1 is harder (235 HB vs 155 HB). ER70S-2 conducts heat better (48 W/m·K vs 40 W/m·K). On the shop floor, ER70S-2 machines more easily (good vs fair), ER70S-2 welds better (excellent vs very good), and ER70S-2 sits in a lower cost tier (standard, $$) than ER100S-1 (premium, $$$).

ER100S-1Choose it when strength drives the design.

ER70S-2Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

ER100S-1 vs ER70S-2: properties

ER100S-1ER70S-2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
560 MPa81.2 ksi

Yield Strength (0.2% offset)

690 MPa100 ksi
450 MPa65.3 ksi

Elongation at Break

21%
28%

Reduction in Area

60%
68%

Shear Strength

455 MPa66 ksi
345 MPa50 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
235 MPa34.1 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
115 MPa·√m105 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
120 J88.5 ft·lbf

Hardness, Brinell

235 HB
155 HB

Hardness, Rockwell C

22 HRC
—

Hardness, Vickers

248 HV
163 HV

Compressive Strength

—
450 MPa65.3 ksi

Hardness, Rockwell B

—
82 HRB

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,460°C2,660 °F
1,470°C2,678 °F

Liquidus Temperature

1,510°C2,750 °F
1,520°C2,768 °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

40 W/m·K23.1 BTU/hr·ft·°F
48 W/m·K27.7 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

12.3 µm/m·K6.8 µin/in·°F
12.5 µm/m·K6.9 µin/in·°F

Min Service Temperature

-51°C-60 °F
-30°C-22 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
10.5 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
1.6×10⁻⁷ Ω·m6.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.62 V
-0.61 V

Corrosion Resistance

13 / 100
10 / 100

Manufacturability

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

Machinability

38 / 100
62 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
65%

Weldability

80 / 100
98 / 100

Formability (cold)

40 / 100
70 / 100

Brazeability / Solderability

55 / 100
65 / 100

Polishability

55 / 100
50 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

32 MJ/kg13,758 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

2.5 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
35 L/kg4.2 gal/lb

Typical Recycled Content

30%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

97 kN·m/kg
71 kN·m/kg

Modulus of Resilience

1,161 kJ/m³
494 kJ/m³

Thermal Diffusivity

10.8 mm²/s
13 mm²/s

Thermal Shock Resistance Index

12
10

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-2ER100S-1

Manufacturing and finishing

CapabilityER100S-1ER70S-2
Default condition——
Relative cost$$$ Premium$$ Standard
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.

ER100S-1 vs ER70S-2 — frequently asked

Is ER100S-1 stronger than ER70S-2?

Yes. ER100S-1 has a typical yield strength of 690 MPa (100 ksi) against 450 MPa (65.3 ksi) for ER70S-2 — about 53% more. Tensile strength is 760 MPa (110 ksi) vs 560 MPa (81.2 ksi).

Which is cheaper, ER100S-1 or ER70S-2?

ER70S-2 is the lower-cost material: it sits in the standard tier ($$) while ER100S-1 is premium ($$$). 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, ER100S-1 or ER70S-2?

ER70S-2. Its machinability rates good (62/100) against fair (38/100) for ER100S-1; for welding the order is ER70S-2 first (excellent, 98/100) then ER100S-1 (very good, 80/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in ER100S-1 and ER70S-2 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.