Steel Medium Carbon Steel-HR vs Medium Carbon Steel Q&T
Steel · Medium Carbon Steel temper comparison
Medium Carbon Steel-HR and Medium Carbon Steel Q&T are two conditions of the same steel grade, Medium Carbon Steel: HR (hot rolled) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. Medium Carbon Steel Q&T is the stronger of the two: yield strength 660 MPa (95.7 ksi) against 330 MPa (47.9 ksi) for Medium Carbon Steel-HR, about 100% more; tensile strength follows at 830 MPa (120 ksi) vs 585 MPa (84.8 ksi). Medium Carbon Steel Q&T is harder — 250 HB against 179 HB for Medium Carbon Steel-HR — which matters for wear surfaces and threads. On the shop floor, Medium Carbon Steel-HR welds better (50 vs 35 out of 100) and Medium Carbon Steel-HR forms better (fair vs poor).
Medium Carbon Steel-HRChoose it when it will be welded.
Medium Carbon Steel Q&TChoose it when strength drives the design, or when surface hardness matters.
Medium Carbon Steel-HR vs Medium Carbon Steel Q&T: 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.
Medium Carbon Steel-HRMedium Carbon Steel Q&T
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
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 · Elongation at Break 16% · Compressive Strength 330 MPa47.9 ksi · Hardness, Rockwell B 88 HRB
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.
Thermal Conductivity
Same in both: 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 · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 10 % IACS · Electrical Resistivity 1.7×10⁻⁷ Ω·m6.69 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.62 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 60 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Embodied Carbon (primary production) 2 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.
Medium Carbon Steel-HR vs Medium Carbon Steel Q&T — frequently asked
Is Medium Carbon Steel Q&T stronger than Medium Carbon Steel-HR?
Yes. Medium Carbon Steel Q&T has a typical yield strength of 660 MPa (95.7 ksi) against 330 MPa (47.9 ksi) for Medium Carbon Steel-HR — about 100% more. Tensile strength is 830 MPa (120 ksi) vs 585 MPa (84.8 ksi).
Which condition does FabDigit quote by default, HR or Q&T?
HR is the default Medium Carbon Steel 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, Medium Carbon Steel-HR or Medium Carbon Steel Q&T?
Medium Carbon Steel-HR. Its machinability rates good (55/100) against fair (48/100) for Medium Carbon Steel Q&T; for welding the order is Medium Carbon Steel-HR first (fair, 50/100) then Medium Carbon Steel Q&T (fair, 35/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Medium Carbon Steel-HR and Medium Carbon Steel Q&T 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.