Steel 1.2714 Prehard vs 1.2714 QT38-42
Steel · 1.2714 temper comparison
1.2714 Prehard and 1.2714 QT38-42 are two conditions of the same steel grade, 1.2714: Prehard (pre-hardened) versus QT38-42 (Q&T 38–42 HRC). The chemistry is identical, so every difference below comes from the condition. 1.2714 QT38-42 is the stronger of the two: yield strength 1,120 MPa (162 ksi) against 850 MPa (123 ksi) for 1.2714 Prehard, about 32% more; tensile strength follows at 1,300 MPa (189 ksi) vs 1,000 MPa (145 ksi). In exchange, 1.2714 Prehard is the more ductile: elongation 13% versus 11% for 1.2714 QT38-42, and 1.2714 QT38-42 is harder (375 HB vs 295 HB). 1.2714 Prehard runs hotter in service (500°C vs 450°C continuous). On the shop floor, 1.2714 Prehard machines more easily (50 vs 35 out of 100).
1.2714 PrehardChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
1.2714 QT38-42Choose it when strength drives the design.
1.2714 Prehard vs 1.2714 QT38-42: 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
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 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 900 MPa131 ksi · Shear Strength 620 MPa89.9 ksi
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °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 34 W/m·K19.6 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.5 µm/m·K6.9 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 2.5×10⁻⁷ Ω·m9.84 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Corrosion Resistance 12 / 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 25 / 100 · Formability (cold) 12 / 100 · Brazeability / Solderability 30 / 100 · Polishability 60 / 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 50 L/kg6 gal/lb · Typical Recycled Content 35%
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.
1.2714 Prehard vs 1.2714 QT38-42 — frequently asked
Is 1.2714 QT38-42 stronger than 1.2714 Prehard?
Yes. 1.2714 QT38-42 has a typical yield strength of 1,120 MPa (162 ksi) against 850 MPa (123 ksi) for 1.2714 Prehard — about 32% more. Tensile strength is 1,300 MPa (189 ksi) vs 1,000 MPa (145 ksi).
Which condition does FabDigit quote by default, Prehard or QT38-42?
Prehard is the default 1.2714 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, 1.2714 Prehard or 1.2714 QT38-42?
1.2714 Prehard, by a small margin. Both rate fair for machinability — 50/100 against 35/100 for 1.2714 QT38-42.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1.2714 Prehard and 1.2714 QT38-42 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.