FabDigit

18CrNi8 vs 8620 and 2 more: properties

18CrNi88620EN3535120

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
205 GPa29.7 Msi
210 GPa30.5 Msi
205 GPa29.7 Msi

Bulk Modulus

165 GPa23.9 Msi
160 GPa23.2 Msi
160 GPa23.2 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

870 MPa126 ksi
635 MPa92.1 ksi
760 MPa110 ksi
470 MPa68.2 ksi

Yield Strength (0.2% offset)

570 MPa82.7 ksi
385 MPa55.8 ksi
480 MPa69.6 ksi
295 MPa42.8 ksi

Elongation at Break

13%
28%
18%
25%

Reduction in Area

45%
60%
50%
55%

Compressive Strength

590 MPa85.6 ksi
490 MPa71.1 ksi
295 MPa42.8 ksi

Shear Strength

530 MPa76.9 ksi
390 MPa56.6 ksi
460 MPa66.7 ksi
300 MPa43.5 ksi

Fatigue Strength (Endurance Limit)

390 MPa56.6 ksi
295 MPa42.8 ksi
350 MPa50.8 ksi
235 MPa34.1 ksi

Fracture Toughness (K_IC)

70 MPa·√m63.7 ksi·√in
85 MPa·√m77.4 ksi·√in
75 MPa·√m68.3 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
90 J66.4 ft·lbf
45 J33.2 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

255 HB
183 HB
229 HB
145 HB

Hardness, Rockwell C

25 HRC
20 HRC

Hardness, Vickers

268 HV
240 HV
152 HV

Hardness, Rockwell B

90 HRB
98 HRB
78 HRB

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

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,420°C2,588 °F
1,425°C2,597 °F
1,420°C2,588 °F
1,420°C2,588 °F

Liquidus Temperature

1,490°C2,714 °F
1,505°C2,741 °F
1,495°C2,723 °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

34 W/m·K19.6 BTU/hr·ft·°F
46.6 W/m·K26.9 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F
46 W/m·K26.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

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

Latent Heat of Fusion

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

Max Service Temperature (continuous)

200°C392 °F
400°C752 °F
200°C392 °F
350°C662 °F

Min Service Temperature

-40°C-40 °F
-40°C-40 °F
-40°C-40 °F
-30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

6.9 % IACS
8 % IACS
7.8 % IACS
7.8 % IACS

Electrical Resistivity

2.5×10⁻⁷ Ω·m9.84 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

12 / 100
11 / 100
12 / 100
12 / 100

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.61 V
-0.61 V

Manufacturability

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

Machinability

40 / 100
62 / 100
55 / 100
62 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
65%
58%
65%

Weldability

30 / 100
60 / 100
42 / 100
60 / 100

Formability (cold)

35 / 100
55 / 100
45 / 100
58 / 100

Brazeability / Solderability

55 / 100
65 / 100
55 / 100
70 / 100

Polishability

65 / 100
70 / 100
60 / 100
55 / 100

Castability

30 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

33 MJ/kg14,187 BTU/lb
30 MJ/kg12,898 BTU/lb
30 MJ/kg12,898 BTU/lb
25 MJ/kg10,748 BTU/lb

Embodied Carbon (primary production)

2.3 kg CO₂/kg
2.1 kg CO₂/kg
2.1 kg CO₂/kg
1.9 kg CO₂/kg

Embodied Water

55 L/kg6.6 gal/lb
60 L/kg7.2 gal/lb
60 L/kg7.2 gal/lb
45 L/kg5.4 gal/lb

Typical Recycled Content

30%
30%
25%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

111 kN·m/kg
81 kN·m/kg
97 kN·m/kg
60 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.1 MN·m/kg
26.8 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

774 kJ/m³
362 kJ/m³
549 kJ/m³
212 kJ/m³

Thermal Diffusivity

9.3 mm²/s
12.5 mm²/s
11.9 mm²/s
12.5 mm²/s

Thermal Shock Resistance Index

12
12
13
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 scale8620EN353512018CrNi8

Manufacturing and finishing

Capability18CrNi88620EN3535120
Default conditionHRHRHRHR
Relative cost$$ Standard$$ Standard$$ Standard$$ Standard
Min. machined wall0.8 mm0.8 mm0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µmRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. 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.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 18CrNi8 and 8620 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.