Steel 28NiCrMoV8-5 +A vs 28NiCrMoV8-5 +QT800
Steel · 28NiCrMoV8-5 temper comparison
28NiCrMoV8-5 +A and 28NiCrMoV8-5 +QT800 are two conditions of the same steel grade, 28NiCrMoV8-5: +A (annealed) versus +QT800 (quenched and tempered, 800–950 MPa class). The chemistry is identical, so every difference below comes from the condition. 28NiCrMoV8-5 +QT800 is the stronger of the two: yield strength 720 MPa (104 ksi) against 420 MPa (60.9 ksi) for 28NiCrMoV8-5 +A, about 71% more; tensile strength follows at 880 MPa (128 ksi) vs 640 MPa (92.8 ksi). In exchange, 28NiCrMoV8-5 +A is the more ductile: elongation 22% versus 16% for 28NiCrMoV8-5 +QT800, and 28NiCrMoV8-5 +QT800 is harder (270 HB vs 200 HB). On the shop floor, 28NiCrMoV8-5 +A machines more easily (good vs fair).
28NiCrMoV8-5 +AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
28NiCrMoV8-5 +QT800Choose it when strength drives the design.
28NiCrMoV8-5 +A vs 28NiCrMoV8-5 +QT800: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all 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 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.
28NiCrMoV8-5 +A28NiCrMoV8-5 +QT800
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29 · Compressive Strength 730 MPa106 ksi · Shear Strength 540 MPa78.3 ksi · Fracture Toughness (K_IC) 130 MPa·√m118 ksi·√in · Hardness, Rockwell C 27 HRC · Hardness, Vickers 285 HV
Physical
Density and transition temperatures.
Same in both: Density 7.83 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 36 W/m·K20.8 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.5 % IACS · Electrical Resistivity 2.3×10⁻⁷ Ω·m9.06 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 13 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Same in both: Weldability 30 / 100 · Formability (cold) 20 / 100 · Brazeability / Solderability 40 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.4 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 25%
Strength versus weight
Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
28NiCrMoV8-5 +A vs 28NiCrMoV8-5 +QT800 — frequently asked
Is 28NiCrMoV8-5 +QT800 stronger than 28NiCrMoV8-5 +A?
Yes. 28NiCrMoV8-5 +QT800 has a typical yield strength of 720 MPa (104 ksi) against 420 MPa (60.9 ksi) for 28NiCrMoV8-5 +A — about 71% more. Tensile strength is 880 MPa (128 ksi) vs 640 MPa (92.8 ksi).
Which condition does FabDigit quote by default, +A or +QT800?
+QT800 is the default 28NiCrMoV8-5 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, 28NiCrMoV8-5 +A or 28NiCrMoV8-5 +QT800?
28NiCrMoV8-5 +A. Its machinability rates good (58/100) against fair (45/100) for 28NiCrMoV8-5 +QT800.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 28NiCrMoV8-5 +A and 28NiCrMoV8-5 +QT800 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.