Steel S1 vs S5
Steel · grade comparison
Steel S1 and S5 are both steel grades, both tool steel. S5 is the stronger of the two: yield strength 440 MPa (63.8 ksi) against 415 MPa (60.2 ksi) for S1, about 6% more. S5 is harder — 215 HB against 200 HB for S1 — which matters for wear surfaces and threads. S5 runs hotter in service (400°C vs 200°C continuous) and S1 conducts electricity better (7.5 % IACS vs 4 % IACS).
S5Choose it when strength drives the design, or when surface hardness matters.
S1 vs S5: 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)
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 207 GPa30 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Elongation at Break 25% · Reduction in Area 45% · Charpy V-Notch Impact (RT) 60 J44.3 ft·lbf
Physical
Density and transition temperatures.
Density
Liquidus Temperature
Same in both: Melting Point (Solidus) 1,420°C2,588 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
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 · Thermal Expansion (CTE, 20–100 °C) 12.4 µm/m·K6.9 µin/in·°F
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
Weldability
Formability (cold)
Brazeability / Solderability
Castability
Same in both: Machinability Rating (AISI 1212 = 100 %) 55% · Polishability 60 / 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 7
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 | S1 | S5 |
|---|---|---|
| Default condition | Annealed | Annealed |
| Relative cost | $$$ Premium | $$$ Premium |
| 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.
S1 vs S5 — frequently asked
Is S5 stronger than S1?
Yes. S5 has a typical yield strength of 440 MPa (63.8 ksi) against 415 MPa (60.2 ksi) for S1 — about 6% more. Tensile strength is 725 MPa (105 ksi) vs 690 MPa (100 ksi).
Which is cheaper, S1 or S5?
Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, S1 or S5?
S5, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for S1; for welding the order is S5 first (poor, 25/100) then S1 (poor, 20/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in S1 and S5 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.