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Steel D2 vs P20

Steel · grade comparison

Steel D2 and P20 are both steel grades. D2 is the stronger of the two: tensile strength 750 MPa (109 ksi) against 700 MPa (102 ksi) for P20, about 7% more. In exchange, P20 is the more ductile: elongation 20% versus 15% for D2, and D2 is harder (220 HB vs 200 HB). P20 runs hotter in service (450°C vs 400°C continuous) and P20 conducts heat better (32 W/m·K vs 20 W/m·K). On the shop floor, P20 machines more easily (good vs poor) and P20 welds better (fair vs poor).

D2Choose it when strength drives the design.

P20Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

D2 vs P20: properties

D2P20

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
205 GPa29.7 Msi

Tensile Strength (Ultimate)

750 MPa109 ksi
700 MPa102 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
440 MPa63.8 ksi

Elongation at Break

15%
20%

Reduction in Area

30%
55%

Shear Strength

470 MPa68.2 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
460 MPa66.7 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

220 HB
200 HB

Hardness, Rockwell B

97 HRB
93 HRB

Hardness, Vickers

230 HV
315 HV

Fracture Toughness (K_IC)

—
65 MPa·√m59.2 ksi·√in

Hardness, Rockwell C

—
31 HRC

Same in both: Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 900 MPa131 ksi

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,421°C2,590 °F
1,420°C2,588 °F

Liquidus Temperature

—
1,480°C2,696 °F

Thermal

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

Thermal Conductivity

20 W/m·K11.6 BTU/hr·ft·°F
32 W/m·K18.5 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10.5 µm/m·K5.8 µin/in·°F
12.4 µm/m·K6.9 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
450°C842 °F

Min Service Temperature

-50°C-58 °F
-20°C-4 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

2.7 % IACS
—

Electrical Resistivity

6.5×10⁻⁷ Ω·m25.6 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.35 V
-0.6 V

Corrosion Resistance

28 / 100
15 / 100

Manufacturability

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

Machinability

30 / 100
65 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
75%

Weldability

15 / 100
50 / 100

Formability (cold)

15 / 100
30 / 100

Castability

25 / 100
—

Brazeability / Solderability

35 / 100
40 / 100

Polishability

65 / 100
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)

3 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

80 L/kg9.6 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

45%
40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

97 kN·m/kg
90 kN·m/kg

Specific Stiffness (E / density)

27.3 MN·m/kg
26.3 MN·m/kg

Modulus of Resilience

482 kJ/m³
472 kJ/m³

Thermal Diffusivity

5.6 mm²/s
8.9 mm²/s

Thermal Shock Resistance Index

7
9

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 scaleD2P20

Manufacturing and finishing

CapabilityD2P20
Default conditionAnnealedAnnealed
Relative cost$$$$$ Specialty$$$$$ Specialty
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.

D2 vs P20 — frequently asked

Is D2 stronger than P20?

Yes. D2 has a typical tensile strength of 750 MPa (109 ksi) against 700 MPa (102 ksi) for P20 — about 7% more.

Which is cheaper, D2 or P20?

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

Which is easier to machine, D2 or P20?

P20. Its machinability rates good (65/100) against poor (30/100) for D2; for welding the order is P20 first (fair, 50/100) then D2 (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in D2 and P20 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.