Steel 1524 CARB-QT vs 1524-HR
Steel · 1524 temper comparison
1524 CARB-QT and 1524-HR are two conditions of the same steel grade, 1524: CARB-QT (carburized, quenched & low-temper) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 1524 CARB-QT is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 305 MPa (44.2 ksi) for 1524-HR, about 70% more; tensile strength follows at 760 MPa (110 ksi) vs 510 MPa (74 ksi). In exchange, 1524-HR is the more ductile: elongation 20% versus 14% for 1524 CARB-QT, and 1524 CARB-QT is harder (235 HB vs 149 HB). 1524-HR runs hotter in service (400°C vs 180°C continuous). On the shop floor, 1524-HR machines more easily (good vs poor) and 1524-HR welds better (very good vs poor).
1524 CARB-QTChoose it when strength drives the design.
1524-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
1524 CARB-QT vs 1524-HR: 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)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 305 MPa44.2 ksi · Shear Strength 330 MPa47.9 ksi · Fracture Toughness (K_IC) 70 MPa·√m63.7 ksi·√in · Hardness, Rockwell B 80 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,500°C2,732 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 51.9 W/m·K30 BTU/hr·ft·°F · Specific Heat Capacity 486 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.7 µm/m·K6.5 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 10.8 % IACS · Electrical Resistivity 1.6×10⁻⁷ Ω·m6.3 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 10 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 40 / 100 · Brazeability / Solderability 70 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 24 MJ/kg10,318 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 30%
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.
1524 CARB-QT vs 1524-HR — frequently asked
Is 1524 CARB-QT stronger than 1524-HR?
Yes. 1524 CARB-QT has a typical yield strength of 520 MPa (75.4 ksi) against 305 MPa (44.2 ksi) for 1524-HR — about 70% more. Tensile strength is 760 MPa (110 ksi) vs 510 MPa (74 ksi).
Which condition does FabDigit quote by default, CARB-QT or HR?
HR is the default 1524 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, 1524 CARB-QT or 1524-HR?
1524-HR. Its machinability rates good (55/100) against poor (20/100) for 1524 CARB-QT; for welding the order is 1524-HR first (very good, 70/100) then 1524 CARB-QT (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1524 CARB-QT and 1524-HR 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.