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Steel E90C-B9 vs ER70S-2

Steel · grade comparison

Steel E90C-B9 and ER70S-2 are both steel grades. E90C-B9 is the stronger of the two: yield strength 600 MPa (87 ksi) against 450 MPa (65.3 ksi) for ER70S-2, about 33% more; tensile strength follows at 710 MPa (103 ksi) vs 560 MPa (81.2 ksi). In exchange, ER70S-2 is the more ductile: elongation 28% versus 20% for E90C-B9, and E90C-B9 is harder (245 HB vs 155 HB). E90C-B9 is stiffer (218 GPa vs 205 GPa) and E90C-B9 runs hotter in service (600°C vs 400°C continuous). On the shop floor, ER70S-2 machines more easily (good vs fair), ER70S-2 welds better (excellent vs fair), and ER70S-2 sits in a lower cost tier (standard, $$) than E90C-B9 (high, $$$$).

E90C-B9Choose it when strength drives the design, or when the part sees heat.

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

E90C-B9 vs ER70S-2: properties

E90C-B9ER70S-2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

218 GPa31.6 Msi
205 GPa29.7 Msi

Shear Modulus

84 GPa12.2 Msi
80 GPa11.6 Msi

Bulk Modulus

165 GPa23.9 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

710 MPa103 ksi
560 MPa81.2 ksi

Yield Strength (0.2% offset)

600 MPa87 ksi
450 MPa65.3 ksi

Elongation at Break

20%
28%

Reduction in Area

60%
68%

Shear Strength

430 MPa62.4 ksi
345 MPa50 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
235 MPa34.1 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
115 MPa·√m105 ksi·√in

Charpy V-Notch Impact (RT)

70 J51.6 ft·lbf
120 J88.5 ft·lbf

Hardness, Brinell

245 HB
155 HB

Hardness, Rockwell C

23 HRC
—

Hardness, Vickers

255 HV
163 HV

Compressive Strength

—
450 MPa65.3 ksi

Hardness, Rockwell B

—
82 HRB

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,425°C2,597 °F
1,470°C2,678 °F

Liquidus Temperature

1,500°C2,732 °F
1,520°C2,768 °F

Thermal

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

Thermal Conductivity

26 W/m·K15 BTU/hr·ft·°F
48 W/m·K27.7 BTU/hr·ft·°F

Specific Heat Capacity

480 J/kg·K0.11 BTU/lb·°F
470 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

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

Max Service Temperature (continuous)

600°C1,112 °F
400°C752 °F

Min Service Temperature

-20°C-4 °F
-30°C-22 °F

Same in both: Latent Heat of Fusion 270 J/g116 BTU/lb

Electrical

Conductivity and insulation.

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 µΩ·in
1.6×10⁻⁷ Ω·m6.3 µΩ·in

Electrical Conductivity

—
10.5 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.45 V
-0.61 V

Corrosion Resistance

30 / 100
10 / 100

Manufacturability

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

Machinability

35 / 100
62 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
65%

Weldability

45 / 100
98 / 100

Formability (cold)

20 / 100
70 / 100

Polishability

55 / 100
50 / 100

Brazeability / Solderability

—
65 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

38 MJ/kg16,337 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

2.9 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

70 L/kg8.4 gal/lb
35 L/kg4.2 gal/lb

Same in both: Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

92 kN·m/kg
71 kN·m/kg

Specific Stiffness (E / density)

28.1 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

826 kJ/m³
494 kJ/m³

Thermal Diffusivity

7 mm²/s
13 mm²/s

Thermal Shock Resistance Index

8
10

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-2E90C-B9

Manufacturing and finishing

CapabilityE90C-B9ER70S-2
Default condition——
Relative cost$$$$ High$$ 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.

E90C-B9 vs ER70S-2 — frequently asked

Is E90C-B9 stronger than ER70S-2?

Yes. E90C-B9 has a typical yield strength of 600 MPa (87 ksi) against 450 MPa (65.3 ksi) for ER70S-2 — about 33% more. Tensile strength is 710 MPa (103 ksi) vs 560 MPa (81.2 ksi).

Which is cheaper, E90C-B9 or ER70S-2?

ER70S-2 is the lower-cost material: it sits in the standard tier ($$) while E90C-B9 is high ($$$$). 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, E90C-B9 or ER70S-2?

ER70S-2. Its machinability rates good (62/100) against fair (35/100) for E90C-B9; for welding the order is ER70S-2 first (excellent, 98/100) then E90C-B9 (fair, 45/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in E90C-B9 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.