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Steel GCr9-HR vs GCr9-IH

Steel · GCr9 temper comparison

GCr9-HR and GCr9-IH are two conditions of the same steel grade, GCr9: HR (hot rolled) versus IH (induction hardened). The chemistry is identical, so every difference below comes from the condition. GCr9-IH is the stronger of the two: yield strength 1,000 MPa (145 ksi) against 550 MPa (79.8 ksi) for GCr9-HR, about 82% more; tensile strength follows at 1,200 MPa (174 ksi) vs 900 MPa (131 ksi). In exchange, GCr9-HR is the more ductile: elongation 12% versus 2% for GCr9-IH, and GCr9-IH is harder (620 HB vs 270 HB). GCr9-HR runs hotter in service (200°C vs 150°C continuous). On the shop floor, GCr9-HR machines more easily (28 vs 15 out of 100).

GCr9-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

GCr9-IHChoose it when strength drives the design.

GCr9-HR vs GCr9-IH: properties

GCr9-HRGCr9-IH

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

900 MPa131 ksi
1,200 MPa174 ksi

Yield Strength (0.2% offset)

550 MPa79.8 ksi
1,000 MPa145 ksi

Elongation at Break

12%
2%

Reduction in Area

25%
5%

Compressive Strength

580 MPa84.1 ksi
2,100 MPa305 ksi

Shear Strength

540 MPa78.3 ksi
780 MPa113 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
600 MPa87 ksi

Charpy V-Notch Impact (RT)

10 J7.4 ft·lbf
15 J11.1 ft·lbf

Hardness, Brinell

270 HB
620 HB

Hardness, Rockwell B

100 HRB
92 HRB

Hardness, Vickers

285 HV
700 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Same in both: Density 7.81 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,470°C2,678 °F

Thermal

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

Thermal Conductivity

43 W/m·K24.8 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
150°C302 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7 % IACS
6.5 % IACS

Electrical Resistivity

2.5×10⁻⁷ Ω·m9.84 µΩ·in
2.7×10⁻⁷ Ω·m10.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

28 / 100
15 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
8%

Weldability

12 / 100
5 / 100

Formability (cold)

20 / 100
3 / 100

Same in both: Brazeability / Solderability 35 / 100 · Polishability 85 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 25%

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 scaleGCr9

GCr9-HR vs GCr9-IH — frequently asked

Is GCr9-IH stronger than GCr9-HR?

Yes. GCr9-IH has a typical yield strength of 1,000 MPa (145 ksi) against 550 MPa (79.8 ksi) for GCr9-HR — about 82% more. Tensile strength is 1,200 MPa (174 ksi) vs 900 MPa (131 ksi).

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

A is the default GCr9 condition in the FabDigit quote flow (neither HR nor IH). 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, GCr9-HR or GCr9-IH?

GCr9-HR, by a small margin. Both rate poor for machinability — 28/100 against 15/100 for GCr9-IH; for welding the order is GCr9-HR first (not recommended, 12/100) then GCr9-IH (not recommended, 5/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in GCr9-HR and GCr9-IH 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.