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Stainless Steel 415 vs 420

Stainless Steel · grade comparison

Stainless Steel 415 and 420 are both stainless steel grades. 415 is the stronger of the two: yield strength 700 MPa (102 ksi) against 360 MPa (52.2 ksi) for 420, about 94% more; tensile strength follows at 850 MPa (123 ksi) vs 690 MPa (100 ksi). In exchange, 420 is the more ductile: elongation 22% versus 18% for 415, and 415 is harder (260 HB vs 200 HB). 420 runs hotter in service (650°C vs 450°C continuous). On the shop floor, 415 welds better (very good vs poor).

415Choose 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.

415 vs 420: properties

415420

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

77 GPa11.2 Msi
78 GPa11.3 Msi

Bulk Modulus

165 GPa23.9 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

850 MPa123 ksi
690 MPa100 ksi

Yield Strength (0.2% offset)

700 MPa102 ksi
360 MPa52.2 ksi

Elongation at Break

18%
22%

Reduction in Area

60%
55%

Compressive Strength

700 MPa102 ksi
380 MPa55.1 ksi

Shear Strength

520 MPa75.4 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
350 MPa50.8 ksi

Fracture Toughness (K_IC)

150 MPa·√m137 ksi·√in
60 MPa·√m54.6 ksi·√in

Charpy V-Notch Impact (RT)

120 J88.5 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

260 HB
200 HB

Hardness, Rockwell C

25 HRC
—

Hardness, Vickers

275 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

25 W/m·K14.4 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)

450°C842 °F
650°C1,202 °F

Min Service Temperature

-100°C-148 °F
-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).

Corrosion Resistance

48 / 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

40 / 100
45 / 100

Weldability

72 / 100
25 / 100

Formability (cold)

35 / 100
40 / 100

Castability

70 / 100
45 / 100

Polishability

65 / 100
85 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 45% · Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

53 MJ/kg22,786 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

4.5 kg CO₂/kg
3.5 kg CO₂/kg

Embodied Water

140 L/kg16.8 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

50%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

110 kN·m/kg
89 kN·m/kg

Specific Stiffness (E / density)

26 MN·m/kg
25.8 MN·m/kg

Modulus of Resilience

1,225 kJ/m³
324 kJ/m³

Thermal Diffusivity

7.6 mm²/s
7 mm²/s

Thermal Shock Resistance Index

10
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 scale420415

Manufacturing and finishing

Capability415420
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.

415 vs 420 — frequently asked

Is 415 stronger than 420?

Yes. 415 has a typical yield strength of 700 MPa (102 ksi) against 360 MPa (52.2 ksi) for 420 — about 94% more. Tensile strength is 850 MPa (123 ksi) vs 690 MPa (100 ksi).

Which is cheaper, 415 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, 415 or 420?

420, by a small margin. Both rate fair for machinability — 45/100 against 40/100 for 415; for welding the order is 415 first (very good, 72/100) then 420 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 415 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.