Steel 3J53 vs Alloy 79
Steel · grade comparison
Steel 3J53 and Alloy 79 are both steel grades. 3J53 is the stronger of the two: yield strength 330 MPa (47.9 ksi) against 270 MPa (39.2 ksi) for Alloy 79, about 22% more; tensile strength follows at 760 MPa (110 ksi) vs 550 MPa (79.8 ksi). In exchange, Alloy 79 is the more ductile: elongation 40% versus 35% for 3J53, and 3J53 is harder (172 HB vs 120 HB). 3J53 is lighter (8.14 g/cm³ vs 8.74 g/cm³ for Alloy 79) and Alloy 79 is stiffer (205 GPa vs 155 GPa). On the shop floor, Alloy 79 welds better (good vs fair).
3J53Choose it when strength drives the design, or when weight is the constraint.
Alloy 79Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
3J53 vs Alloy 79: 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
Physical
Density and transition temperatures.
Density
Same in both: Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,450°C2,642 °F
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
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Same in both: Machinability Rating (AISI 1212 = 100 %) 30%
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
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 | Alloy 79 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
3J53 vs Alloy 79 — frequently asked
Is 3J53 stronger than Alloy 79?
Yes. 3J53 has a typical yield strength of 330 MPa (47.9 ksi) against 270 MPa (39.2 ksi) for Alloy 79 — about 22% more. Tensile strength is 760 MPa (110 ksi) vs 550 MPa (79.8 ksi).
Which is cheaper, 3J53 or Alloy 79?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which welds better, 3J53 or Alloy 79?
Alloy 79. Its weldability rates good (60/100) against fair (50/100) for 3J53.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 3J53 and Alloy 79 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.