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Steel 9SiCr-A vs 9SiCr-HR

Steel · 9SiCr temper comparison

9SiCr-A and 9SiCr-HR are two conditions of the same steel grade, 9SiCr: A (solution annealed) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 9SiCr-HR is the stronger of the two: yield strength 550 MPa (79.8 ksi) against 450 MPa (65.3 ksi) for 9SiCr-A, about 22% more; tensile strength follows at 900 MPa (131 ksi) vs 760 MPa (110 ksi). In exchange, 9SiCr-A is the more ductile: elongation 18% versus 10% for 9SiCr-HR, and 9SiCr-HR is harder (280 HB vs 220 HB). On the shop floor, 9SiCr-A machines more easily (fair vs poor).

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

9SiCr-HRChoose it when strength drives the design.

9SiCr-A vs 9SiCr-HR: properties

9SiCr-A9SiCr-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
900 MPa131 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
550 MPa79.8 ksi

Elongation at Break

18%
10%

Reduction in Area

35%
28%

Compressive Strength

900 MPa131 ksi
1,100 MPa160 ksi

Shear Strength

460 MPa66.7 ksi
540 MPa78.3 ksi

Fatigue Strength (Endurance Limit)

350 MPa50.8 ksi
400 MPa58 ksi

Charpy V-Notch Impact (RT)

15 J11.1 ft·lbf
9 J6.6 ft·lbf

Hardness, Brinell

220 HB
280 HB

Hardness, Vickers

230 HV
295 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.

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 · Max Service Temperature (continuous) 300°C572 °F · 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

45 / 100
32 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
30%

Weldability

12 / 100
10 / 100

Formability (cold)

30 / 100
15 / 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-A vs 9SiCr-HR — frequently asked

Is 9SiCr-HR stronger than 9SiCr-A?

Yes. 9SiCr-HR has a typical yield strength of 550 MPa (79.8 ksi) against 450 MPa (65.3 ksi) for 9SiCr-A — about 22% more. Tensile strength is 900 MPa (131 ksi) vs 760 MPa (110 ksi).

Which condition does FabDigit quote by default, A or HR?

A is the default 9SiCr 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, 9SiCr-A or 9SiCr-HR?

9SiCr-A. Its machinability rates fair (45/100) against poor (32/100) for 9SiCr-HR.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 9SiCr-A and 9SiCr-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.