Steel 3J53 vs FeSi75
Steel · grade comparison
Steel 3J53 and FeSi75 are both steel grades. 3J53 is the stronger of the two: tensile strength 760 MPa (110 ksi) against 120 MPa (17.4 ksi) for FeSi75, about 6.3 times as much. 3J53 is the more ductile: elongation 35% versus 0% for FeSi75, and FeSi75 is harder (900 HV vs 180 HV). FeSi75 is lighter (3 g/cm³ vs 8.14 g/cm³ for 3J53) and FeSi75 runs hotter in service (800°C vs 150°C continuous). On the shop floor, 3J53 machines more easily (fair vs not recommended), 3J53 welds better (fair vs not recommended), and FeSi75 sits in a lower cost tier (budget, $) than 3J53 (high, $$$$).
3J53Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
FeSi75Choose it when weight is the constraint, or when the part sees heat.
3J53 vs FeSi75: 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
Bulk Modulus
Poisson's Ratio
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
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Latent Heat of Fusion
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)
Brazeability / Solderability
Polishability
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)
Thermal Diffusivity
Thermal Shock Resistance Index
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 | 3J53 | FeSi75 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $ Budget |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
3J53 vs FeSi75 — frequently asked
Is 3J53 stronger than FeSi75?
Yes. 3J53 has a typical tensile strength of 760 MPa (110 ksi) against 120 MPa (17.4 ksi) for FeSi75 — about 6.3 times as much.
Which is cheaper, 3J53 or FeSi75?
FeSi75 is the lower-cost material: it sits in the budget tier ($) while 3J53 is high ($$$$). 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, 3J53 or FeSi75?
3J53. Its machinability rates fair (35/100) against not recommended (3/100) for FeSi75; for welding the order is 3J53 first (fair, 50/100) then FeSi75 (not recommended, 3/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 3J53 and FeSi75 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.