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Stainless Steel 1.4405-A vs 1.4405-QT900

Stainless Steel · 1.4405 temper comparison

1.4405-A and 1.4405-QT900 are two conditions of the same stainless steel grade, 1.4405: A (solution annealed) versus QT900. The chemistry is identical, so every difference below comes from the condition. 1.4405-QT900 is the stronger of the two: yield strength 800 MPa (116 ksi) against 480 MPa (69.6 ksi) for 1.4405-A, about 67% more; tensile strength follows at 980 MPa (142 ksi) vs 720 MPa (104 ksi). In exchange, 1.4405-A is the more ductile: elongation 20% versus 12% for 1.4405-QT900, and 1.4405-QT900 is harder (320 HB vs 235 HB). 1.4405-A runs hotter in service (400°C vs 350°C continuous). On the shop floor, 1.4405-A machines more easily (fair vs poor) and 1.4405-A welds better (good vs fair).

1.4405-AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

1.4405-QT900Choose it when strength drives the design.

1.4405-A vs 1.4405-QT900: properties

1.4405-A1.4405-QT900

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

720 MPa104 ksi
980 MPa142 ksi

Yield Strength (0.2% offset)

480 MPa69.6 ksi
800 MPa116 ksi

Elongation at Break

20%
12%

Reduction in Area

58%
40%

Compressive Strength

495 MPa71.8 ksi
820 MPa119 ksi

Shear Strength

440 MPa63.8 ksi
590 MPa85.6 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
420 MPa60.9 ksi

Fracture Toughness (K_IC)

135 MPa·√m123 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

100 J73.8 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

235 HB
320 HB

Hardness, Rockwell C

21 HRC
34 HRC

Hardness, Vickers

245 HV
338 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3

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 1,455°C2,651 °F

Thermal

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

Thermal Conductivity

25 W/m·K14.4 BTU/hr·ft·°F
24.5 W/m·K14.2 BTU/hr·ft·°F

Max Service Temperature (continuous)

400°C752 °F
350°C662 °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 -80°C-112 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

7.8×10⁻⁷ Ω·m30.7 µΩ·in
7.9×10⁻⁷ Ω·m31.1 µΩ·in

Same in both: Electrical Conductivity 2.2 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

55 / 100
53 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.25 V

Manufacturability

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

Machinability

45 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
32%

Weldability

68 / 100
50 / 100

Formability (cold)

18 / 100
7 / 100

Same in both: Castability 65 / 100 · Brazeability / Solderability 30 / 100 · Polishability 60 / 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 110 L/kg13.2 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 scale1.4405

1.4405-A vs 1.4405-QT900 — frequently asked

Is 1.4405-QT900 stronger than 1.4405-A?

Yes. 1.4405-QT900 has a typical yield strength of 800 MPa (116 ksi) against 480 MPa (69.6 ksi) for 1.4405-A — about 67% more. Tensile strength is 980 MPa (142 ksi) vs 720 MPa (104 ksi).

Which condition does FabDigit quote by default, A or QT900?

QT760 is the default 1.4405 condition in the FabDigit quote flow (neither A nor QT900). 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, 1.4405-A or 1.4405-QT900?

1.4405-A. Its machinability rates fair (45/100) against poor (28/100) for 1.4405-QT900; for welding the order is 1.4405-A first (good, 68/100) then 1.4405-QT900 (fair, 50/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.4405-A and 1.4405-QT900 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.