FabDigitFabDigit

Steel 100Cr6 vs GCr9

Steel · grade comparison

Steel 100Cr6 and GCr9 are both steel grades. 100Cr6 is the stronger of the two: yield strength 420 MPa (60.9 ksi) against 390 MPa (56.6 ksi) for GCr9, about 8% more. 100Cr6 is harder — 200 HB against 190 HB for GCr9 — which matters for wear surfaces and threads. 100Cr6 runs hotter in service (200°C vs 150°C continuous) and 100Cr6 conducts electricity better (8 % IACS vs 7 % IACS). On the shop floor, GCr9 forms better (45 vs 35 out of 100) and GCr9 sits in a lower cost tier (budget, $) than 100Cr6 (standard, $$).

100Cr6Choose it when strength drives the design, or when surface hardness matters.

GCr9Choose it when cost is the deciding factor.

100Cr6 vs GCr9: properties

100Cr6GCr9

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Poisson's Ratio

0.29
0.3

Tensile Strength (Ultimate)

660 MPa95.7 ksi
640 MPa92.8 ksi

Yield Strength (0.2% offset)

420 MPa60.9 ksi
390 MPa56.6 ksi

Elongation at Break

22%
23%

Reduction in Area

48%
45%

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

200 HB
190 HB

Hardness, Rockwell B

94 HRB
92 HRB

Hardness, Vickers

210 HV
198 HV

Compressive Strength

—
420 MPa60.9 ksi

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Shear Strength 400 MPa58 ksi · Fatigue Strength (Endurance Limit) 300 MPa43.5 ksi

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,424°C2,595 °F
1,425°C2,597 °F

Liquidus Temperature

1,455°C2,651 °F
1,470°C2,678 °F

Same in both: Density 7.81 g/cm³0.28 lb/in³

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Specific Heat Capacity

470 J/kg·K0.11 BTU/lb·°F
460 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

11.9 µm/m·K6.6 µin/in·°F
12 µm/m·K6.7 µin/in·°F

Max Service Temperature (continuous)

200°C392 °F
150°C302 °F

Min Service Temperature

-40°C-40 °F
-60°C-76 °F

Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
7 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2.5×10⁻⁷ Ω·m9.84 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 Rating (AISI 1212 = 100 %)

40%
35%

Weldability

12 / 100
15 / 100

Formability (cold)

35 / 100
45 / 100

Castability

30 / 100
—

Brazeability / Solderability

45 / 100
35 / 100

Polishability

88 / 100
85 / 100

Same in both: Machinability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

32 MJ/kg13,758 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

2.3 kg CO₂/kg
2.2 kg CO₂/kg

Embodied Water

65 L/kg7.8 gal/lb
55 L/kg6.6 gal/lb

Typical Recycled Content

30%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

85 kN·m/kg
82 kN·m/kg

Modulus of Resilience

420 kJ/m³
362 kJ/m³

Thermal Diffusivity

12.3 mm²/s
12.2 mm²/s

Thermal Shock Resistance Index

12
11

Same in both: Specific Stiffness (E / density) 26.9 MN·m/kg

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 scale100Cr6GCr9

Manufacturing and finishing

Capability100Cr6GCr9
CNC machiningYes—
Sheet metalYes—
Default conditionAnnealed—
Relative cost$$ Standard$ Budget
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
E-CoatingYes—
HVOF CoatingYes—
Hot-Dip GalvanizingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

100Cr6 vs GCr9 — frequently asked

Is 100Cr6 stronger than GCr9?

Yes. 100Cr6 has a typical yield strength of 420 MPa (60.9 ksi) against 390 MPa (56.6 ksi) for GCr9 — about 8% more. Tensile strength is 660 MPa (95.7 ksi) vs 640 MPa (92.8 ksi).

Which is cheaper, 100Cr6 or GCr9?

GCr9 is the lower-cost material: it sits in the budget tier ($) while 100Cr6 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

When should I choose 100Cr6 over GCr9?

Pick 100Cr6 when strength drives the design, or when surface hardness matters. Pick GCr9 when cost is the deciding factor.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 100Cr6 and GCr9 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.