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Steel 15B35 vs 94B30

Steel · grade comparison

Steel 15B35 and 94B30 are both steel grades. 94B30 is the stronger of the two: yield strength 860 MPa (125 ksi) against 620 MPa (89.9 ksi) for 15B35, about 39% more; tensile strength follows at 990 MPa (144 ksi) vs 730 MPa (106 ksi). 94B30 is the more ductile: elongation 17% versus 13% for 15B35, and 94B30 is harder (293 HB vs 217 HB). 94B30 runs hotter in service (400°C vs 350°C continuous) and 15B35 conducts electricity better (9.5 % IACS vs 7.8 % IACS). On the shop floor, 15B35 machines more easily (good vs fair).

15B35Choose it when the part is machined in volume.

94B30Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

15B35 vs 94B30: properties

15B3594B30

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

730 MPa106 ksi
990 MPa144 ksi

Yield Strength (0.2% offset)

620 MPa89.9 ksi
860 MPa125 ksi

Elongation at Break

13%
17%

Reduction in Area

40%
55%

Compressive Strength

620 MPa89.9 ksi
—

Shear Strength

440 MPa63.8 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
470 MPa68.2 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

217 HB
293 HB

Hardness, Rockwell B

96 HRB
—

Fracture Toughness (K_IC)

—
85 MPa·√m77.4 ksi·√in

Hardness, Rockwell C

—
30 HRC

Hardness, Vickers

—
305 HV

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)

1,425°C2,597 °F
1,420°C2,588 °F

Liquidus Temperature

1,495°C2,723 °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

46 W/m·K26.6 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

11.9 µm/m·K6.6 µin/in·°F
12.2 µm/m·K6.8 µin/in·°F

Latent Heat of Fusion

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

Max Service Temperature (continuous)

350°C662 °F
400°C752 °F

Min Service Temperature

-30°C-22 °F
-40°C-40 °F

Same in both: Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.5 % IACS
7.8 % IACS

Electrical Resistivity

1.8×10⁻⁷ Ω·m7.09 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

55 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
50%

Weldability

40 / 100
35 / 100

Formability (cold)

55 / 100
35 / 100

Brazeability / Solderability

60 / 100
55 / 100

Polishability

55 / 100
60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

1.9 kg CO₂/kg
2 kg CO₂/kg

Embodied Water

40 L/kg4.8 gal/lb
45 L/kg5.4 gal/lb

Typical Recycled Content

30%
25%

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

93 kN·m/kg
126 kN·m/kg

Modulus of Resilience

938 kJ/m³
1,804 kJ/m³

Thermal Diffusivity

12.3 mm²/s
11.3 mm²/s

Thermal Shock Resistance Index

14
17

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 scale15B3594B30

Manufacturing and finishing

Capability15B3594B30
Default condition——
Relative cost$ Budget$ 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.

15B35 vs 94B30 — frequently asked

Is 94B30 stronger than 15B35?

Yes. 94B30 has a typical yield strength of 860 MPa (125 ksi) against 620 MPa (89.9 ksi) for 15B35 — about 39% more. Tensile strength is 990 MPa (144 ksi) vs 730 MPa (106 ksi).

Which is cheaper, 15B35 or 94B30?

Both sit in the same relative cost tier ($, budget); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, 15B35 or 94B30?

15B35. Its machinability rates good (55/100) against fair (45/100) for 94B30; for welding the order is 15B35 first (fair, 40/100) then 94B30 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 15B35 and 94B30 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.