FabDigitFabDigit

Steel 8620 vs M2

Steel · grade comparison

Steel 8620 and M2 are both steel grades. M2 is the stronger of the two: yield strength 570 MPa (82.7 ksi) against 385 MPa (55.8 ksi) for 8620, about 48% more; tensile strength follows at 900 MPa (131 ksi) vs 635 MPa (92.1 ksi). In exchange, 8620 is the more ductile: elongation 28% versus 12% for M2, and M2 is harder (235 HB vs 183 HB). 8620 is lighter (7.85 g/cm³ vs 8.16 g/cm³ for M2) and M2 is stiffer (217 GPa vs 205 GPa). On the shop floor, 8620 machines more easily (good vs fair), 8620 welds better (good vs poor), and 8620 sits in a lower cost tier (standard, $$) than M2 (specialty, $$$$$).

8620Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

M2Choose it when strength drives the design.

8620 vs M2: properties

8620M2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

205 GPa29.7 Msi
217 GPa31.5 Msi

Shear Modulus

80 GPa11.6 Msi
84 GPa12.2 Msi

Poisson's Ratio

0.29
0.28

Tensile Strength (Ultimate)

635 MPa92.1 ksi
900 MPa131 ksi

Yield Strength (0.2% offset)

385 MPa55.8 ksi
570 MPa82.7 ksi

Elongation at Break

28%
12%

Reduction in Area

60%
25%

Shear Strength

390 MPa56.6 ksi
560 MPa81.2 ksi

Fatigue Strength (Endurance Limit)

295 MPa42.8 ksi
420 MPa60.9 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
40 MPa·√m36.4 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

183 HB
235 HB

Hardness, Rockwell B

90 HRB
99 HRB

Compressive Strength

—
600 MPa87 ksi

Hardness, Vickers

—
245 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi

Physical

Density and transition temperatures.

Density

7.85 g/cm³0.28 lb/in³
8.16 g/cm³0.29 lb/in³

Liquidus Temperature

1,505°C2,741 °F
1,480°C2,696 °F

Same in both: Melting Point (Solidus) 1,425°C2,597 °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
21.5 W/m·K12.4 BTU/hr·ft·°F

Specific Heat Capacity

475 J/kg·K0.11 BTU/lb·°F
420 J/kg·K0.1 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

11.6 µm/m·K6.4 µin/in·°F
10.1 µm/m·K5.6 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
3.1 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.55 V

Corrosion Resistance

11 / 100
15 / 100

Manufacturability

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

Machinability

62 / 100
35 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
40%

Weldability

60 / 100
18 / 100

Formability (cold)

55 / 100
12 / 100

Brazeability / Solderability

65 / 100
45 / 100

Same in both: Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
48 MJ/kg20,636 BTU/lb

Embodied Carbon (primary production)

2.1 kg CO₂/kg
3.4 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
70 L/kg8.4 gal/lb

Typical Recycled Content

30%
40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

81 kN·m/kg
110 kN·m/kg

Specific Stiffness (E / density)

26.1 MN·m/kg
26.6 MN·m/kg

Modulus of Resilience

362 kJ/m³
749 kJ/m³

Thermal Diffusivity

12.5 mm²/s
6.3 mm²/s

Thermal Shock Resistance Index

12
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 scale8620M2

Manufacturing and finishing

Capability8620M2
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 M2 — frequently asked

Is M2 stronger than 8620?

Yes. M2 has a typical yield strength of 570 MPa (82.7 ksi) against 385 MPa (55.8 ksi) for 8620 — about 48% more. Tensile strength is 900 MPa (131 ksi) vs 635 MPa (92.1 ksi).

Which is cheaper, 8620 or M2?

8620 is the lower-cost material: it sits in the standard tier ($$) while M2 is specialty ($$$$$). 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 M2?

8620. Its machinability rates good (62/100) against fair (35/100) for M2; for welding the order is 8620 first (good, 60/100) then M2 (poor, 18/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 8620 and M2 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.