FabDigitFabDigit

Steel 15B35 vs 15B62

Steel · grade comparison

Steel 15B35 and 15B62 are both steel grades. 15B35 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 520 MPa (75.4 ksi) for 15B62, about 19% more. 15B62 is harder — 270 HB against 217 HB for 15B35 — which matters for wear surfaces and threads. 15B35 runs hotter in service (350°C vs 250°C continuous) and 15B35 conducts electricity better (9.5 % IACS vs 8 % IACS). On the shop floor, 15B35 machines more easily (good vs fair), 15B35 welds better (fair vs poor), and 15B35 forms better (good vs poor).

15B35Choose it when strength drives the design, or when the part sees heat.

15B62Choose it when surface hardness matters.

15B35 vs 15B62: properties

15B3515B62

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

730 MPa106 ksi
930 MPa135 ksi

Yield Strength (0.2% offset)

620 MPa89.9 ksi
520 MPa75.4 ksi

Elongation at Break

13%
12%

Reduction in Area

40%
30%

Compressive Strength

620 MPa89.9 ksi
—

Shear Strength

440 MPa63.8 ksi
600 MPa87 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
400 MPa58 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
15 J11.1 ft·lbf

Hardness, Brinell

217 HB
270 HB

Hardness, Rockwell B

96 HRB
100 HRB

Fracture Toughness (K_IC)

—
60 MPa·√m54.6 ksi·√in

Hardness, Vickers

—
285 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
1,480°C2,696 °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
45 W/m·K26 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.9 µm/m·K6.6 µin/in·°F
11.5 µm/m·K6.4 µin/in·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

350°C662 °F
250°C482 °F

Same in both: Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.5 % IACS
8 % IACS

Electrical Resistivity

1.8×10⁻⁷ Ω·m7.09 µΩ·in
2.1×10⁻⁷ Ω·m8.27 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
42 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
55%

Weldability

40 / 100
20 / 100

Formability (cold)

55 / 100
30 / 100

Brazeability / Solderability

60 / 100
40 / 100

Same in both: Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

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

Typical Recycled Content

30%
35%

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

93 kN·m/kg
118 kN·m/kg

Modulus of Resilience

938 kJ/m³
660 kJ/m³

Thermal Diffusivity

12.3 mm²/s
12.2 mm²/s

Thermal Shock Resistance Index

14
18

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 scale15B3515B62

Manufacturing and finishing

Capability15B3515B62
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 15B62 — frequently asked

Is 15B35 stronger than 15B62?

Yes. 15B35 has a typical yield strength of 620 MPa (89.9 ksi) against 520 MPa (75.4 ksi) for 15B62 — about 19% more. Tensile strength is 730 MPa (106 ksi) vs 930 MPa (135 ksi).

Which is cheaper, 15B35 or 15B62?

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 15B62?

15B35. Its machinability rates good (55/100) against fair (42/100) for 15B62; for welding the order is 15B35 first (fair, 40/100) then 15B62 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 15B35 and 15B62 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.