Steel 420 Mod Mold vs P20
Steel · grade comparison
Steel 420 Mod Mold and P20 are both steel grades, both mold steel. 420 Mod Mold is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 440 MPa (63.8 ksi) for P20, about 7% more; tensile strength follows at 760 MPa (110 ksi) vs 700 MPa (102 ksi). 420 Mod Mold is harder — 220 HB against 200 HB for P20 — which matters for wear surfaces and threads. P20 runs hotter in service (450°C vs 400°C continuous) and P20 conducts heat better (32 W/m·K vs 24 W/m·K). On the shop floor, P20 machines more easily (good vs fair), P20 welds better (fair vs poor), and 420 Mod Mold sits in a lower cost tier (standard, $$) than P20 (specialty, $$$$$).
420 Mod MoldChoose it when strength drives the design, or when surface hardness matters.
P20Choose it when the part sees heat, or when the part is machined in volume.
420 Mod Mold 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.
Elastic (Young's) Modulus
Shear Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Fracture Toughness (K_IC)
Hardness, Rockwell C
Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Same in both: Liquidus Temperature 1,480°C2,696 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
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 Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 9
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 | 420 Mod Mold | P20 |
|---|---|---|
| Default condition | Annealed | Annealed |
| Relative cost | $$ Standard | $$$$$ Specialty |
| Min. machined wall | 0.8 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 1.6 µm |
Both are offered for CNC machining. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.
420 Mod Mold vs P20 — frequently asked
Is 420 Mod Mold stronger than P20?
Yes. 420 Mod Mold has a typical yield strength of 470 MPa (68.2 ksi) against 440 MPa (63.8 ksi) for P20 — about 7% more. Tensile strength is 760 MPa (110 ksi) vs 700 MPa (102 ksi).
Which is cheaper, 420 Mod Mold or P20?
420 Mod Mold is the lower-cost material: it sits in the standard tier ($$) 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, 420 Mod Mold or P20?
P20. Its machinability rates good (65/100) against fair (45/100) for 420 Mod Mold; for welding the order is P20 first (fair, 50/100) then 420 Mod Mold (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 420 Mod Mold 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.