Steel 1552-HR vs 1552 QT-38-42HRC
Steel · 1552 temper comparison
1552-HR and 1552 QT-38-42HRC are two conditions of the same steel grade, 1552: HR (hot rolled) versus QT-38-42HRC. The chemistry is identical, so every difference below comes from the condition. 1552 QT-38-42HRC is the stronger of the two: yield strength 1,105 MPa (160 ksi) against 415 MPa (60.2 ksi) for 1552-HR, about 166% more; tensile strength follows at 1,275 MPa (185 ksi) vs 725 MPa (105 ksi). In exchange, 1552-HR is the more ductile: elongation 15% versus 11% for 1552 QT-38-42HRC, and 1552 QT-38-42HRC is harder (375 HB vs 207 HB). 1552-HR runs hotter in service (400°C vs 350°C continuous). On the shop floor, 1552-HR machines more easily (fair vs poor) and 1552-HR welds better (poor vs not recommended).
1552-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
1552 QT-38-42HRCChoose it when strength drives the design.
1552-HR vs 1552 QT-38-42HRC: 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 415 MPa60.2 ksi · Shear Strength 435 MPa63.1 ksi · Fracture Toughness (K_IC) 50 MPa·√m45.5 ksi·√in · Hardness, Rockwell B 95 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 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 49 W/m·K28.3 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 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 % IACS · Electrical Resistivity 1.8×10⁻⁷ Ω·m7.09 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 %)
Weldability
Same in both: Formability (cold) 30 / 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 40 L/kg4.8 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.
1552-HR vs 1552 QT-38-42HRC — frequently asked
Is 1552 QT-38-42HRC stronger than 1552-HR?
Yes. 1552 QT-38-42HRC has a typical yield strength of 1,105 MPa (160 ksi) against 415 MPa (60.2 ksi) for 1552-HR — about 166% more. Tensile strength is 1,275 MPa (185 ksi) vs 725 MPa (105 ksi).
Which condition does FabDigit quote by default, HR or QT-38-42HRC?
HR is the default 1552 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, 1552-HR or 1552 QT-38-42HRC?
1552-HR. Its machinability rates fair (52/100) against poor (30/100) for 1552 QT-38-42HRC; for welding the order is 1552-HR first (poor, 30/100) then 1552 QT-38-42HRC (not recommended, 12/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1552-HR and 1552 QT-38-42HRC 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.