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Stainless Steel 20Cb-3 vs N-155 (Multimet)

Stainless Steel · grade comparison

Stainless Steel 20Cb-3 and N-155 (Multimet) are both stainless steel grades. N-155 (Multimet) is the stronger of the two: yield strength 415 MPa (60.2 ksi) against 345 MPa (50 ksi) for 20Cb-3, about 20% more; tensile strength follows at 815 MPa (118 ksi) vs 620 MPa (89.9 ksi). N-155 (Multimet) is harder — 200 HB against 160 HB for 20Cb-3 — which matters for wear surfaces and threads. N-155 (Multimet) runs hotter in service (815°C vs 500°C continuous) and N-155 (Multimet) conducts electricity better (1.9 % IACS vs 1.6 % IACS). On the shop floor, 20Cb-3 machines more easily (33 vs 20 out of 100), 20Cb-3 forms better (very good vs good), and 20Cb-3 sits in a lower cost tier (premium, $$$) than N-155 (Multimet) (high, $$$$).

20Cb-3Choose it when the part is machined in volume, or when cost is the deciding factor.

N-155 (Multimet)Choose it when strength drives the design, or when surface hardness matters.

20Cb-3 vs N-155 (Multimet): properties

20Cb-3N-155 (Multimet)

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

193 GPa28 Msi
200 GPa29 Msi

Shear Modulus

74 GPa10.7 Msi
77 GPa11.2 Msi

Bulk Modulus

161 GPa23.4 Msi
165 GPa23.9 Msi

Tensile Strength (Ultimate)

620 MPa89.9 ksi
815 MPa118 ksi

Yield Strength (0.2% offset)

345 MPa50 ksi
415 MPa60.2 ksi

Elongation at Break

42%
45%

Reduction in Area

60%
45%

Shear Strength

400 MPa58 ksi
540 MPa78.3 ksi

Fatigue Strength (Endurance Limit)

275 MPa39.9 ksi
340 MPa49.3 ksi

Charpy V-Notch Impact (RT)

200 J148 ft·lbf
95 J70.1 ft·lbf

Hardness, Brinell

160 HB
200 HB

Hardness, Rockwell B

83 HRB
93 HRB

Hardness, Vickers

170 HV
210 HV

Same in both: Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Density

8.08 g/cm³0.29 lb/in³
8.19 g/cm³0.3 lb/in³

Melting Point (Solidus)

1,425°C2,597 °F
1,300°C2,372 °F

Liquidus Temperature

1,445°C2,633 °F
1,355°C2,471 °F

Thermal

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

Thermal Conductivity

12.6 W/m·K7.3 BTU/hr·ft·°F
12.3 W/m·K7.1 BTU/hr·ft·°F

Specific Heat Capacity

500 J/kg·K0.12 BTU/lb·°F
430 J/kg·K0.1 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

14.8 µm/m·K8.2 µin/in·°F
14.4 µm/m·K8 µin/in·°F

Max Service Temperature (continuous)

500°C932 °F
815°C1,499 °F

Same in both: Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

1.6 % IACS
1.9 % IACS

Electrical Resistivity

1.08×10⁻⁶ Ω·m42.5 µΩ·in
9.1×10⁻⁷ Ω·m35.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.1 V
—

Corrosion Resistance

72 / 100
68 / 100

Manufacturability

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

Machinability

33 / 100
20 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
15%

Weldability

75 / 100
70 / 100

Formability (cold)

70 / 100
55 / 100

Brazeability / Solderability

55 / 100
70 / 100

Polishability

75 / 100
65 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

110 MJ/kg47,292 BTU/lb
95 MJ/kg40,843 BTU/lb

Embodied Carbon (primary production)

7.5 kg CO₂/kg
8 kg CO₂/kg

Embodied Water

150 L/kg18 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

40%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

77 kN·m/kg
100 kN·m/kg

Specific Stiffness (E / density)

23.9 MN·m/kg
24.4 MN·m/kg

Modulus of Resilience

308 kJ/m³
431 kJ/m³

Thermal Diffusivity

3.1 mm²/s
3.5 mm²/s

Same in both: Thermal Shock Resistance Index 3

Strength versus weight

Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scaleN-155 (Multimet)20Cb-3

Manufacturing and finishing

Capability20Cb-3N-155 (Multimet)
CNC machiningYes—
Sheet metalYes—
Default conditionSolution Annealed—
Relative cost$$$ Premium$$$$ High
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—
ElectropolishingYes—
HVOF CoatingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—
Passivation (Stainless Steel)Yes—

They share 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.

20Cb-3 vs N-155 (Multimet) — frequently asked

Is N-155 (Multimet) stronger than 20Cb-3?

Yes. N-155 (Multimet) has a typical yield strength of 415 MPa (60.2 ksi) against 345 MPa (50 ksi) for 20Cb-3 — about 20% more. Tensile strength is 815 MPa (118 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, 20Cb-3 or N-155 (Multimet)?

20Cb-3 is the lower-cost material: it sits in the premium tier ($$$) while N-155 (Multimet) is high ($$$$). 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, 20Cb-3 or N-155 (Multimet)?

20Cb-3, by a small margin. Both rate poor for machinability — 33/100 against 20/100 for N-155 (Multimet); for welding the order is 20Cb-3 first (very good, 75/100) then N-155 (Multimet) (very good, 70/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 20Cb-3 and N-155 (Multimet) 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.