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Stainless Steel 1.4008 +A vs 1.4008-F

Stainless Steel · 1.4008 temper comparison

1.4008 +A and 1.4008-F are two conditions of the same stainless steel grade, 1.4008: +A (annealed) versus F (as fabricated). The chemistry is identical, so every difference below comes from the condition. 1.4008-F is the stronger of the two: yield strength 700 MPa (102 ksi) against 380 MPa (55.1 ksi) for 1.4008 +A, about 84% more; tensile strength follows at 900 MPa (131 ksi) vs 590 MPa (85.6 ksi). In exchange, 1.4008 +A is the more ductile: elongation 22% versus 4% for 1.4008-F, and 1.4008-F is harder (340 HB vs 180 HB). 1.4008 +A runs hotter in service (600°C vs 300°C continuous). On the shop floor, 1.4008 +A machines more easily (good vs poor) and 1.4008 +A welds better (fair vs poor).

1.4008 +AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

1.4008-FChoose it when strength drives the design.

1.4008 +A vs 1.4008-F: properties

1.4008 +A1.4008-F

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

590 MPa85.6 ksi
900 MPa131 ksi

Yield Strength (0.2% offset)

380 MPa55.1 ksi
700 MPa102 ksi

Elongation at Break

22%
4%

Reduction in Area

55%
10%

Compressive Strength

500 MPa72.5 ksi
720 MPa104 ksi

Shear Strength

420 MPa60.9 ksi
540 MPa78.3 ksi

Fatigue Strength (Endurance Limit)

260 MPa37.7 ksi
370 MPa53.7 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
30 MPa·√m27.3 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
8 J5.9 ft·lbf

Hardness, Brinell

180 HB
340 HB

Hardness, Rockwell C

18 HRC
36 HRC

Hardness, Vickers

220 HV
355 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 78 GPa11.3 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,500°C2,732 °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 W/m·K13.9 BTU/hr·ft·°F

Max Service Temperature (continuous)

600°C1,112 °F
300°C572 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.5 µm/m·K5.8 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.9 % IACS
2.8 % IACS

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 µΩ·in
6.2×10⁻⁷ Ω·m24.4 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

45 / 100
38 / 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

55 / 100
22 / 100

Machinability Rating (AISI 1212 = 100 %)

58%
25%

Weldability

45 / 100
20 / 100

Formability (cold)

10 / 100
3 / 100

Same in both: Castability 65 / 100 · Brazeability / Solderability 45 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Embodied Carbon (primary production) 3.6 kg CO₂/kg · Embodied Water 200 L/kg24 gal/lb · Typical Recycled Content 70%

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 scale1.4008

1.4008 +A vs 1.4008-F — frequently asked

Is 1.4008-F stronger than 1.4008 +A?

Yes. 1.4008-F has a typical yield strength of 700 MPa (102 ksi) against 380 MPa (55.1 ksi) for 1.4008 +A — about 84% more. Tensile strength is 900 MPa (131 ksi) vs 590 MPa (85.6 ksi).

Which condition does FabDigit quote by default, +A or F?

+QT1 is the default 1.4008 condition in the FabDigit quote flow (neither +A nor F). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, 1.4008 +A or 1.4008-F?

1.4008 +A. Its machinability rates good (55/100) against poor (22/100) for 1.4008-F; for welding the order is 1.4008 +A first (fair, 45/100) then 1.4008-F (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.4008 +A and 1.4008-F 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.