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Steel E100C-K3 vs ER70S-3

Steel · grade comparison

Steel E100C-K3 and ER70S-3 are both steel grades. E100C-K3 is the stronger of the two: yield strength 660 MPa (95.7 ksi) against 460 MPa (66.7 ksi) for ER70S-3, about 43% more; tensile strength follows at 745 MPa (108 ksi) vs 550 MPa (79.8 ksi). In exchange, ER70S-3 is the more ductile: elongation 28% versus 20% for E100C-K3, and E100C-K3 is harder (235 HB vs 160 HB). ER70S-3 conducts heat better (48 W/m·K vs 40 W/m·K). On the shop floor, ER70S-3 machines more easily (good vs fair), ER70S-3 welds better (excellent vs very good), and ER70S-3 sits in a lower cost tier (budget, $) than E100C-K3 (premium, $$$).

E100C-K3Choose it when strength drives the design.

ER70S-3Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

E100C-K3 vs ER70S-3: properties

E100C-K3ER70S-3

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

80 GPa11.6 Msi
79 GPa11.5 Msi

Tensile Strength (Ultimate)

745 MPa108 ksi
550 MPa79.8 ksi

Yield Strength (0.2% offset)

660 MPa95.7 ksi
460 MPa66.7 ksi

Elongation at Break

20%
28%

Reduction in Area

60%
65%

Shear Strength

450 MPa65.3 ksi
330 MPa47.9 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
230 MPa33.4 ksi

Fracture Toughness (K_IC)

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

Hardness, Brinell

235 HB
160 HB

Hardness, Rockwell C

22 HRC
—

Hardness, Vickers

245 HV
168 HV

Compressive Strength

—
460 MPa66.7 ksi

Hardness, Rockwell B

—
84 HRB

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Charpy V-Notch Impact (RT) 90 J66.4 ft·lbf

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,450°C2,642 °F
1,470°C2,678 °F

Liquidus Temperature

1,505°C2,741 °F
1,520°C2,768 °F

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 µm/m·K6.7 µin/in·°F

Latent Heat of Fusion

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

Min Service Temperature

-40°C-40 °F
-30°C-22 °F

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

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
10 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
1.7×10⁻⁷ Ω·m6.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.62 V
-0.65 V

Corrosion Resistance

14 / 100
10 / 100

Manufacturability

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

Machinability

42 / 100
58 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
60%

Weldability

70 / 100
95 / 100

Formability (cold)

35 / 100
80 / 100

Brazeability / Solderability

50 / 100
70 / 100

Castability

—
70 / 100

Same in both: Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

36 MJ/kg15,477 BTU/lb
32 MJ/kg13,758 BTU/lb

Embodied Carbon (primary production)

2.6 kg CO₂/kg
2.4 kg CO₂/kg

Same in both: Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

96 kN·m/kg
70 kN·m/kg

Specific Stiffness (E / density)

26.3 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

1,062 kJ/m³
516 kJ/m³

Thermal Diffusivity

10.9 mm²/s
13 mm²/s

Thermal Shock Resistance Index

12
11

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-3E100C-K3

Manufacturing and finishing

CapabilityE100C-K3ER70S-3
Default condition——
Relative cost$$$ Premium$ 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.

E100C-K3 vs ER70S-3 — frequently asked

Is E100C-K3 stronger than ER70S-3?

Yes. E100C-K3 has a typical yield strength of 660 MPa (95.7 ksi) against 460 MPa (66.7 ksi) for ER70S-3 — about 43% more. Tensile strength is 745 MPa (108 ksi) vs 550 MPa (79.8 ksi).

Which is cheaper, E100C-K3 or ER70S-3?

ER70S-3 is the lower-cost material: it sits in the budget tier ($) while E100C-K3 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, E100C-K3 or ER70S-3?

ER70S-3. Its machinability rates good (58/100) against fair (42/100) for E100C-K3; for welding the order is ER70S-3 first (excellent, 95/100) then E100C-K3 (very good, 70/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in E100C-K3 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.