Steel 718 vs P20
Steel · grade comparison
Steel 718 and P20 are both steel grades, both mold steel. 718 is the stronger of the two: yield strength 880 MPa (128 ksi) against 440 MPa (63.8 ksi) for P20, about 100% more; tensile strength follows at 1,030 MPa (149 ksi) vs 700 MPa (102 ksi). In exchange, P20 is the more ductile: elongation 20% versus 14% for 718, and 718 is harder (310 HB vs 200 HB). P20 runs hotter in service (450°C vs 400°C continuous). On the shop floor, P20 machines more easily (65 vs 55 out of 100) and 718 sits in a lower cost tier (standard, $$) than P20 (specialty, $$$$$).
718Choose it when strength drives the design, or when cost is the deciding factor.
P20Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
718 vs P20: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Hardness, Rockwell B
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 900 MPa131 ksi · Shear Strength 620 MPa89.9 ksi
Physical
Density and transition temperatures.
Liquidus Temperature
Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
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 · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Same in both: Corrosion Resistance 15 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Polishability
Same in both: Brazeability / Solderability 40 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Water 60 L/kg7.2 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 26.3 MN·m/kg · Thermal Diffusivity 8.9 mm²/s
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 | 718 | P20 |
|---|---|---|
| Default condition | Prehard | Annealed |
| Relative cost | $$ Standard | $$$$$ Specialty |
| Min. machined wall | 0.8 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 1.6 µm |
Both are offered for CNC machining. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.
718 vs P20 — frequently asked
Is 718 stronger than P20?
Yes. 718 has a typical yield strength of 880 MPa (128 ksi) against 440 MPa (63.8 ksi) for P20 — about 100% more. Tensile strength is 1,030 MPa (149 ksi) vs 700 MPa (102 ksi).
Which is cheaper, 718 or P20?
718 is the lower-cost material: it sits in the standard tier ($$) while P20 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, 718 or P20?
P20, by a small margin. Both rate good for machinability — 65/100 against 55/100 for 718; for welding the order is P20 first (fair, 50/100) then 718 (fair, 45/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 718 and P20 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.