Stainless Steel 1.4029 +A vs 1.4029 +QT850
Stainless Steel · 1.4029 temper comparison
1.4029 +A and 1.4029 +QT850 are two conditions of the same stainless steel grade, 1.4029: +A (annealed) versus +QT850 (quenched and tempered, Rm 850–1000 MPa). The chemistry is identical, so every difference below comes from the condition. 1.4029 +QT850 is the stronger of the two: yield strength 700 MPa (102 ksi) against 450 MPa (65.3 ksi) for 1.4029 +A, about 56% more; tensile strength follows at 920 MPa (133 ksi) vs 740 MPa (107 ksi). In exchange, 1.4029 +A is the more ductile: elongation 15% versus 10% for 1.4029 +QT850, and 1.4029 +QT850 is harder (275 HB vs 215 HB). On the shop floor, 1.4029 +A machines more easily (good vs fair).
1.4029 +AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
1.4029 +QT850Choose it when strength drives the design.
1.4029 +A vs 1.4029 +QT850: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 215 GPa31.2 Msi · Shear Modulus 82 GPa11.9 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 96 HRB
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 1,480°C2,696 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 30 W/m·K17.3 BTU/hr·ft·°F · 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 260 J/g112 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 3.1 % IACS · Electrical Resistivity 5.5×10⁻⁷ Ω·m21.7 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
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
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 12 / 100 · Brazeability / Solderability 40 / 100 · Polishability 35 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 40 MJ/kg17,197 BTU/lb · Embodied Carbon (primary production) 3.4 kg CO₂/kg · Embodied Water 120 L/kg14.4 gal/lb · Typical Recycled Content 60%
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.
1.4029 +A vs 1.4029 +QT850 — frequently asked
Is 1.4029 +QT850 stronger than 1.4029 +A?
Yes. 1.4029 +QT850 has a typical yield strength of 700 MPa (102 ksi) against 450 MPa (65.3 ksi) for 1.4029 +A — about 56% more. Tensile strength is 920 MPa (133 ksi) vs 740 MPa (107 ksi).
Which condition does FabDigit quote by default, +A or +QT850?
+A is the default 1.4029 condition in the FabDigit quote flow. 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, 1.4029 +A or 1.4029 +QT850?
1.4029 +A. Its machinability rates good (65/100) against fair (48/100) for 1.4029 +QT850.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1.4029 +A and 1.4029 +QT850 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.