Steel 5015 CARB-RQT vs 5015-HR
Steel · 5015 temper comparison
5015 CARB-RQT and 5015-HR are two conditions of the same steel grade, 5015: CARB-RQT (carburized, reheat quenched and tempered) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 5015 CARB-RQT is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 275 MPa (39.9 ksi) for 5015-HR, about 89% more; tensile strength follows at 720 MPa (104 ksi) vs 440 MPa (63.8 ksi). In exchange, 5015-HR is the more ductile: elongation 30% versus 16% for 5015 CARB-RQT, and 5015 CARB-RQT is harder (650 HB vs 126 HB). 5015-HR runs hotter in service (400°C vs 180°C continuous). On the shop floor, 5015-HR machines more easily (fair vs poor) and 5015-HR welds better (very good vs poor).
5015 CARB-RQTChoose it when strength drives the design.
5015-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
5015 CARB-RQT vs 5015-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
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
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 1,510°C2,750 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 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: Brazeability / Solderability 70 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 45 L/kg5.4 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.
5015 CARB-RQT vs 5015-HR — frequently asked
Is 5015 CARB-RQT stronger than 5015-HR?
Yes. 5015 CARB-RQT has a typical yield strength of 520 MPa (75.4 ksi) against 275 MPa (39.9 ksi) for 5015-HR — about 89% more. Tensile strength is 720 MPa (104 ksi) vs 440 MPa (63.8 ksi).
Which condition does FabDigit quote by default, CARB-RQT or HR?
A is the default 5015 condition in the FabDigit quote flow (neither CARB-RQT nor HR). 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, 5015 CARB-RQT or 5015-HR?
5015-HR. Its machinability rates fair (54/100) against poor (18/100) for 5015 CARB-RQT; for welding the order is 5015-HR first (very good, 78/100) then 5015 CARB-RQT (poor, 20/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 5015 CARB-RQT and 5015-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.