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Steel 10B21 vs 94B30

Steel · grade comparison

Steel 10B21 and 94B30 are both steel grades. 94B30 is the stronger of the two: yield strength 860 MPa (125 ksi) against 290 MPa (42.1 ksi) for 10B21, about 197% more; tensile strength follows at 990 MPa (144 ksi) vs 430 MPa (62.4 ksi). In exchange, 10B21 is the more ductile: elongation 30% versus 17% for 94B30, and 94B30 is harder (293 HB vs 126 HB). 10B21 conducts heat better (51.9 W/m·K vs 42 W/m·K). On the shop floor, 10B21 machines more easily (good vs fair) and 10B21 welds better (excellent vs fair).

10B21Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

94B30Choose it when strength drives the design.

10B21 vs 94B30: properties

10B2194B30

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

430 MPa62.4 ksi
990 MPa144 ksi

Yield Strength (0.2% offset)

290 MPa42.1 ksi
860 MPa125 ksi

Elongation at Break

30%
17%

Shear Strength

275 MPa39.9 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
470 MPa68.2 ksi

Fracture Toughness (K_IC)

90 MPa·√m81.9 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

65 J47.9 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

126 HB
293 HB

Hardness, Rockwell B

71 HRB
—

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 · Reduction in Area 55%

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,465°C2,669 °F
1,420°C2,588 °F

Liquidus Temperature

1,510°C2,750 °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

51.9 W/m·K30 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.7 µm/m·K6.5 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

Min Service Temperature

-30°C-22 °F
-40°C-40 °F

Same in both: Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10.8 % IACS
7.8 % IACS

Electrical Resistivity

1.6×10⁻⁷ Ω·m6.3 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

62 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
50%

Weldability

85 / 100
35 / 100

Formability (cold)

82 / 100
35 / 100

Brazeability / Solderability

70 / 100
55 / 100

Polishability

45 / 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)

55 kN·m/kg
126 kN·m/kg

Modulus of Resilience

205 kJ/m³
1,804 kJ/m³

Thermal Diffusivity

14.1 mm²/s
11.3 mm²/s

Thermal Shock Resistance Index

9
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 scale10B2194B30

Manufacturing and finishing

Capability10B2194B30
CNC machiningYes—
Sheet metalYes—
Default conditionHR—
Relative cost$ Budget$ Budget
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
E-CoatingYes—
HVOF CoatingYes—
Hot-Dip GalvanizingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

10B21 vs 94B30 — frequently asked

Is 94B30 stronger than 10B21?

Yes. 94B30 has a typical yield strength of 860 MPa (125 ksi) against 290 MPa (42.1 ksi) for 10B21 — about 197% more. Tensile strength is 990 MPa (144 ksi) vs 430 MPa (62.4 ksi).

Which is cheaper, 10B21 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, 10B21 or 94B30?

10B21. Its machinability rates good (62/100) against fair (45/100) for 94B30; for welding the order is 10B21 first (excellent, 85/100) then 94B30 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 10B21 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.