Steel 8407 QT40-44 vs 8407 QT48-50
Steel · 8407 temper comparison
8407 QT40-44 and 8407 QT48-50 are two conditions of the same steel grade, 8407: QT40-44 (Q&T 40–44 HRC) versus QT48-50 (Q&T 48–50 HRC). The chemistry is identical, so every difference below comes from the condition. 8407 QT48-50 is the stronger of the two: yield strength 1,450 MPa (210 ksi) against 1,150 MPa (167 ksi) for 8407 QT40-44, about 26% more; tensile strength follows at 1,750 MPa (254 ksi) vs 1,350 MPa (196 ksi). In exchange, 8407 QT40-44 is the more ductile: elongation 12% versus 9% for 8407 QT48-50, and 8407 QT40-44 is harder (390 HB vs 180 HB). On the shop floor, 8407 QT40-44 machines more easily (poor vs not recommended).
8407 QT40-44Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
8407 QT48-50Choose it when strength drives the design.
8407 QT40-44 vs 8407 QT48-50: 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.
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, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 175 GPa25.4 Msi · Poisson's Ratio 0.3 · Hardness, Rockwell B 89 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,480°C2,696 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 25.5 W/m·K14.7 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 3.3 % IACS · Electrical Resistivity 5.2×10⁻⁷ Ω·m20.5 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.55 V · Corrosion Resistance 18 / 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 45 / 100 · Formability (cold) 25 / 100 · Brazeability / Solderability 25 / 100 · Polishability 90 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 35 MJ/kg15,047 BTU/lb · Embodied Carbon (primary production) 2.8 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 45%
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.
8407 QT40-44 vs 8407 QT48-50 — frequently asked
Is 8407 QT48-50 stronger than 8407 QT40-44?
Yes. 8407 QT48-50 has a typical yield strength of 1,450 MPa (210 ksi) against 1,150 MPa (167 ksi) for 8407 QT40-44 — about 26% more. Tensile strength is 1,750 MPa (254 ksi) vs 1,350 MPa (196 ksi).
Which condition does FabDigit quote by default, QT40-44 or QT48-50?
ANN is the default 8407 condition in the FabDigit quote flow (neither QT40-44 nor QT48-50). 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, 8407 QT40-44 or 8407 QT48-50?
8407 QT40-44. Its machinability rates poor (28/100) against not recommended (14/100) for 8407 QT48-50.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 8407 QT40-44 and 8407 QT48-50 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.