FabDigitFabDigit

Stainless Steel 1.4959 vs Alloy 20

Stainless Steel · grade comparison

Stainless Steel 1.4959 and Alloy 20 are both stainless steel grades. Alloy 20 is the stronger of the two: yield strength 310 MPa (45 ksi) against 240 MPa (34.8 ksi) for 1.4959, about 29% more; tensile strength follows at 620 MPa (89.9 ksi) vs 550 MPa (79.8 ksi). In exchange, 1.4959 is the more ductile: elongation 47% versus 40% for Alloy 20, and Alloy 20 is harder (160 HB vs 145 HB). 1.4959 runs hotter in service (1,100°C vs 500°C continuous). On the shop floor, 1.4959 sits in a lower cost tier (high, $$$$) than Alloy 20 (specialty, $$$$$).

1.4959Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Alloy 20Choose it when strength drives the design.

1.4959 vs Alloy 20: properties

1.4959Alloy 20

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

196 GPa28.4 Msi
193 GPa28 Msi

Shear Modulus

73 GPa10.6 Msi
74 GPa10.7 Msi

Bulk Modulus

200 GPa29 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.34
0.3

Tensile Strength (Ultimate)

550 MPa79.8 ksi
620 MPa89.9 ksi

Yield Strength (0.2% offset)

240 MPa34.8 ksi
310 MPa45 ksi

Elongation at Break

47%
40%

Shear Strength

380 MPa55.1 ksi
415 MPa60.2 ksi

Fatigue Strength (Endurance Limit)

235 MPa34.1 ksi
260 MPa37.7 ksi

Charpy V-Notch Impact (RT)

150 J111 ft·lbf
190 J140 ft·lbf

Hardness, Brinell

145 HB
160 HB

Hardness, Rockwell B

80 HRB
85 HRB

Hardness, Vickers

152 HV
—

Same in both: Reduction in Area 60%

Physical

Density and transition temperatures.

Density

7.94 g/cm³0.29 lb/in³
8.08 g/cm³0.29 lb/in³

Melting Point (Solidus)

1,357°C2,475 °F
1,370°C2,498 °F

Liquidus Temperature

1,385°C2,525 °F
1,425°C2,597 °F

Thermal

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

Thermal Conductivity

11.5 W/m·K6.6 BTU/hr·ft·°F
12 W/m·K6.9 BTU/hr·ft·°F

Specific Heat Capacity

460 J/kg·K0.11 BTU/lb·°F
500 J/kg·K0.12 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

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

Latent Heat of Fusion

290 J/g125 BTU/lb
285 J/g123 BTU/lb

Max Service Temperature (continuous)

1,100°C2,012 °F
500°C932 °F

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

Electrical

Conductivity and insulation.

Electrical Conductivity

1.7 % IACS
1.6 % IACS

Electrical Resistivity

1×10⁻⁶ Ω·m39.4 µΩ·in
1.08×10⁻⁶ Ω·m42.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.1 V
-0.08 V

Corrosion Resistance

72 / 100
80 / 100

Manufacturability

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

Machinability

30 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
40%

Weldability

75 / 100
80 / 100

Formability (cold)

70 / 100
72 / 100

Brazeability / Solderability

55 / 100
60 / 100

Polishability

65 / 100
75 / 100

Castability

—
55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

95 MJ/kg40,843 BTU/lb
100 MJ/kg42,992 BTU/lb

Embodied Carbon (primary production)

8.5 kg CO₂/kg
7.5 kg CO₂/kg

Embodied Water

230 L/kg27.6 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

35%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

69 kN·m/kg
77 kN·m/kg

Specific Stiffness (E / density)

24.7 MN·m/kg
23.9 MN·m/kg

Modulus of Resilience

147 kJ/m³
249 kJ/m³

Thermal Diffusivity

3.1 mm²/s
3 mm²/s

Thermal Shock Resistance Index

2
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 scaleAlloy 201.4959

Manufacturing and finishing

Capability1.4959Alloy 20
CNC machining—Yes
Sheet metal—Yes
Default condition—Annealed
Relative cost$$$$ High$$$$$ Specialty
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.

1.4959 vs Alloy 20 — frequently asked

Is Alloy 20 stronger than 1.4959?

Yes. Alloy 20 has a typical yield strength of 310 MPa (45 ksi) against 240 MPa (34.8 ksi) for 1.4959 — about 29% more. Tensile strength is 620 MPa (89.9 ksi) vs 550 MPa (79.8 ksi).

Which is cheaper, 1.4959 or Alloy 20?

1.4959 is the lower-cost material: it sits in the high tier ($$$$) while Alloy 20 is specialty ($$$$$). 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, 1.4959 or Alloy 20?

Alloy 20. Its machinability rates fair (38/100) against poor (30/100) for 1.4959; for welding the order is Alloy 20 first (very good, 80/100) then 1.4959 (very good, 75/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.4959 and Alloy 20 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.