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Stainless Steel 1.4020 vs 304

Stainless Steel · grade comparison

Stainless Steel 1.4020 and 304 are both stainless steel grades. 1.4020 is the stronger of the two: yield strength 390 MPa (56.6 ksi) against 250 MPa (36.3 ksi) for 304, about 56% more; tensile strength follows at 780 MPa (113 ksi) vs 585 MPa (84.8 ksi). 1.4020 is harder — 195 HB against 150 HB for 304 — which matters for wear surfaces and threads. 304 runs hotter in service (870°C vs 760°C continuous). On the shop floor, 304 welds better (excellent vs good) and 304 forms better (excellent vs very good).

1.4020Choose it when strength drives the design, or when surface hardness matters.

304Choose it when the part sees heat, or when it will be welded.

1.4020 vs 304: properties

1.4020304

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

197 GPa28.6 Msi
193 GPa28 Msi

Bulk Modulus

160 GPa23.2 Msi
152 GPa22 Msi

Tensile Strength (Ultimate)

780 MPa113 ksi
585 MPa84.8 ksi

Yield Strength (0.2% offset)

390 MPa56.6 ksi
250 MPa36.3 ksi

Elongation at Break

50%
55%

Reduction in Area

60%
70%

Shear Strength

480 MPa69.6 ksi
415 MPa60.2 ksi

Fatigue Strength (Endurance Limit)

310 MPa45 ksi
250 MPa36.3 ksi

Fracture Toughness (K_IC)

150 MPa·√m137 ksi·√in
220 MPa·√m200 ksi·√in

Charpy V-Notch Impact (RT)

120 J88.5 ft·lbf
200 J148 ft·lbf

Hardness, Brinell

195 HB
150 HB

Hardness, Rockwell B

92 HRB
82 HRB

Hardness, Vickers

205 HV
160 HV

Compressive Strength

—
250 MPa36.3 ksi

Same in both: Shear Modulus 77 GPa11.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

7.8 g/cm³0.28 lb/in³
8 g/cm³0.29 lb/in³

Same in both: Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F

Thermal

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

Thermal Conductivity

15.5 W/m·K9 BTU/hr·ft·°F
16.2 W/m·K9.4 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

17 µm/m·K9.4 µin/in·°F
17.3 µm/m·K9.6 µin/in·°F

Max Service Temperature (continuous)

760°C1,400 °F
870°C1,598 °F

Min Service Temperature

-100°C-148 °F
-196°C-321 °F

Same in both: Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Latent Heat of Fusion 285 J/g123 BTU/lb

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.4 % IACS · Electrical Resistivity 7.2×10⁻⁷ Ω·m28.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.15 V
-0.05 V

Corrosion Resistance

52 / 100
70 / 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

68 / 100
88 / 100

Formability (cold)

75 / 100
90 / 100

Brazeability / Solderability

60 / 100
65 / 100

Polishability

70 / 100
88 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

45 MJ/kg19,347 BTU/lb
53 MJ/kg22,786 BTU/lb

Embodied Carbon (primary production)

3.6 kg CO₂/kg
5.4 kg CO₂/kg

Embodied Water

90 L/kg10.8 gal/lb
110 L/kg13.2 gal/lb

Typical Recycled Content

60%
70%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

100 kN·m/kg
73 kN·m/kg

Specific Stiffness (E / density)

25.3 MN·m/kg
24.1 MN·m/kg

Modulus of Resilience

386 kJ/m³
162 kJ/m³

Thermal Diffusivity

4 mm²/s
4.1 mm²/s

Thermal Shock Resistance Index

4
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 scale3041.4020

Manufacturing and finishing

Capability1.4020304
CNC machining—Yes
Sheet metal—Yes
Casting & forging—Yes
Default condition—Annealed
Relative cost$$ Standard$$ Standard
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.

1.4020 vs 304 — frequently asked

Is 1.4020 stronger than 304?

Yes. 1.4020 has a typical yield strength of 390 MPa (56.6 ksi) against 250 MPa (36.3 ksi) for 304 — about 56% more. Tensile strength is 780 MPa (113 ksi) vs 585 MPa (84.8 ksi).

Which is cheaper, 1.4020 or 304?

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

Which is easier to machine, 1.4020 or 304?

304, by a small margin. Both rate fair for machinability — 45/100 against 38/100 for 1.4020; for welding the order is 304 first (excellent, 88/100) then 1.4020 (good, 68/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.4020 and 304 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.