Steel 100Cr6 vs GCr4
Steel · grade comparison
Steel 100Cr6 and GCr4 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 GCr4, about 8% more. 100Cr6 is harder — 200 HB against 190 HB for GCr4 — which matters for wear surfaces and threads. GCr4 runs hotter in service (250°C vs 200°C continuous) and 100Cr6 conducts electricity better (8 % IACS vs 7 % IACS). On the shop floor, GCr4 sits in a lower cost tier (budget, $) than 100Cr6 (standard, $$).
100Cr6Choose it when strength drives the design, or when surface hardness matters.
GCr4Choose it when the part sees heat, or when cost is the deciding factor.
100Cr6 vs GCr4: 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.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Compressive Strength
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)
Same in both: Density 7.81 g/cm³0.28 lb/in³ · Liquidus Temperature 1,455°C2,651 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
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 %)
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Same in both: Machinability 45 / 100 · Castability 30 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Water
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 2.3 kg CO₂/kg
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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.
Manufacturing and finishing
| Capability | 100Cr6 | GCr4 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | Annealed | — |
| Relative cost | $$ Standard | $ Budget |
| Min. machined wall | 0.8 mm | — |
| Best machined surface | Ra 1.6 µm | — |
| AlCrN | Yes | — |
| AlTiN | Yes | — |
| Black Oxide | Yes | — |
| CVD Al2O3 | Yes | — |
| CVD TiCN | Yes | — |
| CVD TiN | Yes | — |
| Cerakote | Yes | — |
| Chrome Plating | Yes | — |
| CrN | Yes | — |
| DLC | Yes | — |
| E-Coating | Yes | — |
| HVOF Coating | Yes | — |
| Hot-Dip Galvanizing | Yes | — |
| MoS2 | Yes | — |
| Multilayer CVD | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
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 GCr4 — frequently asked
Is 100Cr6 stronger than GCr4?
Yes. 100Cr6 has a typical yield strength of 420 MPa (60.9 ksi) against 390 MPa (56.6 ksi) for GCr4 — about 8% more. Tensile strength is 660 MPa (95.7 ksi) vs 640 MPa (92.8 ksi).
Which is cheaper, 100Cr6 or GCr4?
GCr4 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 GCr4?
Pick 100Cr6 when strength drives the design, or when surface hardness matters. Pick GCr4 when the part sees heat, or when cost is the deciding factor.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 100Cr6 and GCr4 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.