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Steel 9SiCr-HR vs 9SiCr QT48-52

Steel · 9SiCr temper comparison

9SiCr-HR and 9SiCr QT48-52 are two conditions of the same steel grade, 9SiCr: HR (hot rolled) versus QT48-52 (Q&T 48–52 HRC). The chemistry is identical, so every difference below comes from the condition. 9SiCr QT48-52 is the stronger of the two: yield strength 1,450 MPa (210 ksi) against 550 MPa (79.8 ksi) for 9SiCr-HR, about 164% more; tensile strength follows at 1,700 MPa (247 ksi) vs 900 MPa (131 ksi). In exchange, 9SiCr-HR is the more ductile: elongation 10% versus 6% for 9SiCr QT48-52, and 9SiCr-HR is harder (280 HB vs 220 HB). On the shop floor, 9SiCr-HR machines more easily (32 vs 15 out of 100).

9SiCr-HRChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

9SiCr QT48-52Choose it when strength drives the design.

9SiCr-HR vs 9SiCr QT48-52: properties

9SiCr-HR9SiCr QT48-52

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

900 MPa131 ksi
1,700 MPa247 ksi

Yield Strength (0.2% offset)

550 MPa79.8 ksi
1,450 MPa210 ksi

Elongation at Break

10%
6%

Reduction in Area

28%
35%

Compressive Strength

1,100 MPa160 ksi
2,100 MPa305 ksi

Shear Strength

540 MPa78.3 ksi
460 MPa66.7 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
680 MPa98.6 ksi

Charpy V-Notch Impact (RT)

9 J6.6 ft·lbf
20 J14.8 ft·lbf

Hardness, Brinell

280 HB
220 HB

Hardness, Vickers

295 HV
520 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 97 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.75 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,470°C2,678 °F

Thermal

How each material carries heat and how hot it can run.

Max Service Temperature (continuous)

300°C572 °F
320°C608 °F

Same in both: Thermal Conductivity 32 W/m·K18.5 BTU/hr·ft·°F · Specific Heat Capacity 460 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 260 J/g112 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 5.7 % IACS · Electrical Resistivity 3×10⁻⁷ Ω·m11.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 12 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

32 / 100
15 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
45%

Weldability

10 / 100
12 / 100

Formability (cold)

15 / 100
30 / 100

Same in both: Castability 30 / 100 · Brazeability / Solderability 45 / 100 · Polishability 75 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.4 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale9SiCr

9SiCr-HR vs 9SiCr QT48-52 — frequently asked

Is 9SiCr QT48-52 stronger than 9SiCr-HR?

Yes. 9SiCr QT48-52 has a typical yield strength of 1,450 MPa (210 ksi) against 550 MPa (79.8 ksi) for 9SiCr-HR — about 164% more. Tensile strength is 1,700 MPa (247 ksi) vs 900 MPa (131 ksi).

Which condition does FabDigit quote by default, HR or QT48-52?

A is the default 9SiCr condition in the FabDigit quote flow (neither HR nor QT48-52). 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, 9SiCr-HR or 9SiCr QT48-52?

9SiCr-HR, by a small margin. Both rate poor for machinability — 32/100 against 15/100 for 9SiCr QT48-52.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 9SiCr-HR and 9SiCr QT48-52 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.