Steel 15B37-A vs 15B37-HR
Steel · 15B37 temper comparison
15B37-A and 15B37-HR are two conditions of the same steel grade, 15B37: A (solution annealed) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 15B37-HR is the stronger of the two: yield strength 400 MPa (58 ksi) against 340 MPa (49.3 ksi) for 15B37-A, about 18% more; tensile strength follows at 640 MPa (92.8 ksi) vs 570 MPa (82.7 ksi). In exchange, 15B37-A is the more ductile: elongation 28% versus 22% for 15B37-HR, and 15B37-HR is harder (187 HB vs 163 HB).
15B37-AChoose it when the part is bent, formed or impact-loaded.
15B37-HRChoose it when strength drives the design.
15B37-A vs 15B37-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
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 · Shear Strength 660 MPa95.7 ksi · Fracture Toughness (K_IC) 70 MPa·√m63.7 ksi·√in · Hardness, Rockwell C 35 HRC · Hardness, Vickers 345 HV
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 1,495°C2,723 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 300°C572 °F · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 8 % IACS · Electrical Resistivity 2.1×10⁻⁷ Ω·m8.27 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 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 35 / 100 · Brazeability / Solderability 55 / 100 · Polishability 55 / 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 60 L/kg7.2 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.
15B37-A vs 15B37-HR — frequently asked
Is 15B37-HR stronger than 15B37-A?
Yes. 15B37-HR has a typical yield strength of 400 MPa (58 ksi) against 340 MPa (49.3 ksi) for 15B37-A — about 18% more. Tensile strength is 640 MPa (92.8 ksi) vs 570 MPa (82.7 ksi).
Which condition does FabDigit quote by default, A or HR?
QT32-38 is the default 15B37 condition in the FabDigit quote flow (neither A 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, 15B37-A or 15B37-HR?
15B37-A, by a small margin. Both rate good for machinability — 62/100 against 55/100 for 15B37-HR.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 15B37-A and 15B37-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.