Steel 1115 CARB vs 1115-HR
Steel · 1115 temper comparison
1115 CARB and 1115-HR are two conditions of the same steel grade, 1115: CARB (carburized, Quenched & Tempered) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 1115 CARB is the stronger of the two: yield strength 420 MPa (60.9 ksi) against 230 MPa (33.4 ksi) for 1115-HR, about 83% more; tensile strength follows at 620 MPa (89.9 ksi) vs 425 MPa (61.6 ksi). In exchange, 1115-HR is the more ductile: elongation 22% versus 12% for 1115 CARB, and 1115 CARB is harder (200 HB vs 121 HB). On the shop floor, 1115-HR machines more easily (very good vs poor).
1115 CARBChoose it when strength drives the design.
1115-HRChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
1115 CARB vs 1115-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 200 GPa29 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Fracture Toughness (K_IC) 80 MPa·√m72.8 ksi·√in
Physical
Density and transition temperatures.
Same in both: Density 7.87 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,510°C2,750 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 51 W/m·K29.5 BTU/hr·ft·°F · Specific Heat Capacity 486 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · 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) -0.62 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 %)
Formability (cold)
Same in both: Weldability 40 / 100 · Brazeability / Solderability 70 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 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.
1115 CARB vs 1115-HR — frequently asked
Is 1115 CARB stronger than 1115-HR?
Yes. 1115 CARB has a typical yield strength of 420 MPa (60.9 ksi) against 230 MPa (33.4 ksi) for 1115-HR — about 83% more. Tensile strength is 620 MPa (89.9 ksi) vs 425 MPa (61.6 ksi).
Which condition does FabDigit quote by default, CARB or HR?
CD is the default 1115 condition in the FabDigit quote flow (neither CARB 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, 1115 CARB or 1115-HR?
1115-HR. Its machinability rates very good (76/100) against poor (15/100) for 1115 CARB.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1115 CARB and 1115-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.