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Stainless Steel 1.4418 vs 420

Stainless Steel · grade comparison

Stainless Steel 1.4418 and 420 are both stainless steel grades. 1.4418 is the stronger of the two: yield strength 780 MPa (113 ksi) against 360 MPa (52.2 ksi) for 420, about 117% more; tensile strength follows at 980 MPa (142 ksi) vs 690 MPa (100 ksi). In exchange, 420 is the more ductile: elongation 22% versus 17% for 1.4418, and 1.4418 is harder (300 HB vs 200 HB). 420 runs hotter in service (650°C vs 300°C continuous) and 420 conducts heat better (24.9 W/m·K vs 15 W/m·K). On the shop floor, 420 machines more easily (45 vs 35 out of 100) and 1.4418 welds better (good vs poor).

1.4418Choose it when strength drives the design, or when it will be welded.

420Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

1.4418 vs 420: properties

1.4418420

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

77 GPa11.2 Msi
78 GPa11.3 Msi

Bulk Modulus

166 GPa24.1 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

980 MPa142 ksi
690 MPa100 ksi

Yield Strength (0.2% offset)

780 MPa113 ksi
360 MPa52.2 ksi

Elongation at Break

17%
22%

Reduction in Area

58%
55%

Compressive Strength

790 MPa115 ksi
380 MPa55.1 ksi

Shear Strength

590 MPa85.6 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

430 MPa62.4 ksi
350 MPa50.8 ksi

Fracture Toughness (K_IC)

120 MPa·√m109 ksi·√in
60 MPa·√m54.6 ksi·√in

Charpy V-Notch Impact (RT)

70 J51.6 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

300 HB
200 HB

Hardness, Rockwell C

31 HRC
—

Hardness, Vickers

315 HV
210 HV

Hardness, Rockwell B

—
93 HRB

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,400°C2,552 °F
1,454°C2,649 °F

Liquidus Temperature

1,480°C2,696 °F
1,510°C2,750 °F

Thermal

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

Thermal Conductivity

15 W/m·K8.7 BTU/hr·ft·°F
24.9 W/m·K14.4 BTU/hr·ft·°F

Specific Heat Capacity

430 J/kg·K0.1 BTU/lb·°F
460 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

10.5 µm/m·K5.8 µin/in·°F
10.3 µm/m·K5.7 µin/in·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
260 J/g112 BTU/lb

Max Service Temperature (continuous)

300°C572 °F
650°C1,202 °F

Min Service Temperature

-60°C-76 °F
-30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.2 % IACS
3.1 % IACS

Electrical Resistivity

8×10⁻⁷ Ω·m31.5 µΩ·in
5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

55 / 100
40 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.3 V

Manufacturability

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

Machinability

35 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

38%
45%

Weldability

68 / 100
25 / 100

Formability (cold)

22 / 100
40 / 100

Castability

60 / 100
45 / 100

Polishability

75 / 100
85 / 100

Same in both: Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

5.5 kg CO₂/kg
3.5 kg CO₂/kg

Embodied Water

200 L/kg24 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

60%
45%

Same in both: Embodied Energy (primary production) 55 MJ/kg23,646 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

127 kN·m/kg
89 kN·m/kg

Specific Stiffness (E / density)

26 MN·m/kg
25.8 MN·m/kg

Modulus of Resilience

1,521 kJ/m³
324 kJ/m³

Thermal Diffusivity

4.5 mm²/s
7 mm²/s

Thermal Shock Resistance Index

7
8

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 scale4201.4418

Manufacturing and finishing

Capability1.4418420
CNC machining—Yes
Default condition—Annealed
Relative cost$$$ Premium$$$ Premium
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
Electropolishing—Yes
HVOF Coating—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes
Passivation (Stainless Steel)—Yes

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

1.4418 vs 420 — frequently asked

Is 1.4418 stronger than 420?

Yes. 1.4418 has a typical yield strength of 780 MPa (113 ksi) against 360 MPa (52.2 ksi) for 420 — about 117% more. Tensile strength is 980 MPa (142 ksi) vs 690 MPa (100 ksi).

Which is cheaper, 1.4418 or 420?

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

Which is easier to machine, 1.4418 or 420?

420, by a small margin. Both rate fair for machinability — 45/100 against 35/100 for 1.4418; for welding the order is 1.4418 first (good, 68/100) then 420 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.4418 and 420 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.