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Stainless Steel 1.4903 vs 420

Stainless Steel · grade comparison

Stainless Steel 1.4903 and 420 are both stainless steel grades. 1.4903 is the stronger of the two: yield strength 490 MPa (71.1 ksi) against 360 MPa (52.2 ksi) for 420, about 36% more. 1.4903 is harder — 215 HB against 200 HB for 420 — which matters for wear surfaces and threads. 1.4903 is stiffer (218 GPa vs 200 GPa). On the shop floor, 1.4903 welds better (fair vs poor) and 420 forms better (fair vs poor).

1.4903Choose it when strength drives the design, or when surface hardness matters.

1.4903 vs 420: properties

1.4903420

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

218 GPa31.6 Msi
200 GPa29 Msi

Shear Modulus

84 GPa12.2 Msi
78 GPa11.3 Msi

Bulk Modulus

175 GPa25.4 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

660 MPa95.7 ksi
690 MPa100 ksi

Yield Strength (0.2% offset)

490 MPa71.1 ksi
360 MPa52.2 ksi

Elongation at Break

23%
22%

Reduction in Area

65%
55%

Compressive Strength

500 MPa72.5 ksi
380 MPa55.1 ksi

Shear Strength

400 MPa58 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
350 MPa50.8 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
60 MPa·√m54.6 ksi·√in

Charpy V-Notch Impact (RT)

130 J95.9 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

215 HB
200 HB

Hardness, Rockwell B

95 HRB
93 HRB

Hardness, Rockwell C

19 HRC
—

Hardness, Vickers

225 HV
210 HV

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,450°C2,642 °F
1,454°C2,649 °F

Liquidus Temperature

1,500°C2,732 °F
1,510°C2,750 °F

Thermal

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

Thermal Conductivity

26.5 W/m·K15.3 BTU/hr·ft·°F
24.9 W/m·K14.4 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

10.8 µm/m·K6 µin/in·°F
10.3 µm/m·K5.7 µin/in·°F

Latent Heat of Fusion

265 J/g114 BTU/lb
260 J/g112 BTU/lb

Max Service Temperature (continuous)

600°C1,112 °F
650°C1,202 °F

Same in both: Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.9 % IACS
3.1 % IACS

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 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)

-0.45 V
-0.3 V

Corrosion Resistance

28 / 100
40 / 100

Manufacturability

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

Machinability

38 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
45%

Weldability

42 / 100
25 / 100

Formability (cold)

30 / 100
40 / 100

Brazeability / Solderability

35 / 100
40 / 100

Polishability

62 / 100
85 / 100

Castability

—
45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

35 MJ/kg15,047 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

2.6 kg CO₂/kg
3.5 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

35%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

85 kN·m/kg
89 kN·m/kg

Specific Stiffness (E / density)

28.1 MN·m/kg
25.8 MN·m/kg

Modulus of Resilience

551 kJ/m³
324 kJ/m³

Thermal Diffusivity

7.1 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 scale4201.4903

Manufacturing and finishing

Capability1.4903420
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.

1.4903 vs 420 — frequently asked

Is 1.4903 stronger than 420?

Yes. 1.4903 has a typical yield strength of 490 MPa (71.1 ksi) against 360 MPa (52.2 ksi) for 420 — about 36% more. Tensile strength is 660 MPa (95.7 ksi) vs 690 MPa (100 ksi).

Which is cheaper, 1.4903 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, 1.4903 or 420?

420, by a small margin. Both rate fair for machinability — 45/100 against 38/100 for 1.4903; for welding the order is 1.4903 first (fair, 42/100) then 420 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.4903 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.