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Steel 8620 vs D2

Steel · grade comparison

Steel 8620 and D2 are both steel grades. D2 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 385 MPa (55.8 ksi) for 8620, about 17% more; tensile strength follows at 750 MPa (109 ksi) vs 635 MPa (92.1 ksi). In exchange, 8620 is the more ductile: elongation 28% versus 15% for D2, and D2 is harder (220 HB vs 183 HB). 8620 conducts heat better (46.6 W/m·K vs 20 W/m·K). On the shop floor, 8620 machines more easily (good vs poor), 8620 welds better (good vs poor), and 8620 sits in a lower cost tier (standard, $$) than D2 (specialty, $$$$$).

8620Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

D2Choose it when strength drives the design.

8620 vs D2: properties

8620D2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

205 GPa29.7 Msi
210 GPa30.5 Msi

Tensile Strength (Ultimate)

635 MPa92.1 ksi
750 MPa109 ksi

Yield Strength (0.2% offset)

385 MPa55.8 ksi
450 MPa65.3 ksi

Elongation at Break

28%
15%

Reduction in Area

60%
30%

Shear Strength

390 MPa56.6 ksi
470 MPa68.2 ksi

Fatigue Strength (Endurance Limit)

295 MPa42.8 ksi
340 MPa49.3 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
—

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

183 HB
220 HB

Hardness, Rockwell B

90 HRB
97 HRB

Compressive Strength

—
900 MPa131 ksi

Hardness, Vickers

—
230 HV

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

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,425°C2,597 °F
1,421°C2,590 °F

Liquidus Temperature

1,505°C2,741 °F
—

Thermal

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

Thermal Conductivity

46.6 W/m·K26.9 BTU/hr·ft·°F
20 W/m·K11.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.6 µm/m·K6.4 µin/in·°F
10.5 µm/m·K5.8 µin/in·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
250 J/g107 BTU/lb

Min Service Temperature

-40°C-40 °F
-50°C-58 °F

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

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
2.7 % IACS

Electrical Resistivity

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

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.35 V

Corrosion Resistance

11 / 100
28 / 100

Manufacturability

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

Machinability

62 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
30%

Weldability

60 / 100
15 / 100

Formability (cold)

55 / 100
15 / 100

Brazeability / Solderability

65 / 100
35 / 100

Polishability

70 / 100
65 / 100

Castability

—
25 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
36 MJ/kg15,477 BTU/lb

Embodied Carbon (primary production)

2.1 kg CO₂/kg
3 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

30%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

81 kN·m/kg
97 kN·m/kg

Specific Stiffness (E / density)

26.1 MN·m/kg
27.3 MN·m/kg

Modulus of Resilience

362 kJ/m³
482 kJ/m³

Thermal Diffusivity

12.5 mm²/s
5.6 mm²/s

Thermal Shock Resistance Index

12
7

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 scale8620D2

Manufacturing and finishing

Capability8620D2
Sheet metalYes—
Default conditionHRAnnealed
Relative cost$$ Standard$$$$$ 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.

8620 vs D2 — frequently asked

Is D2 stronger than 8620?

Yes. D2 has a typical yield strength of 450 MPa (65.3 ksi) against 385 MPa (55.8 ksi) for 8620 — about 17% more. Tensile strength is 750 MPa (109 ksi) vs 635 MPa (92.1 ksi).

Which is cheaper, 8620 or D2?

8620 is the lower-cost material: it sits in the standard tier ($$) while D2 is specialty ($$$$$). 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, 8620 or D2?

8620. Its machinability rates good (62/100) against poor (30/100) for D2; for welding the order is 8620 first (good, 60/100) then D2 (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 8620 and D2 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.