Steel 30Q130 vs Alloy 79
Steel · grade comparison
Steel 30Q130 and Alloy 79 are both steel grades. 30Q130 is the stronger of the two: yield strength 315 MPa (45.7 ksi) against 270 MPa (39.2 ksi) for Alloy 79, about 17% more. In exchange, Alloy 79 is the more ductile: elongation 40% versus 8% for 30Q130, and 30Q130 is harder (160 HB vs 120 HB). 30Q130 is lighter (7.65 g/cm³ vs 8.74 g/cm³ for Alloy 79) and Alloy 79 is stiffer (205 GPa vs 120 GPa). On the shop floor, Alloy 79 welds better (good vs fair) and 30Q130 sits in a lower cost tier (standard, $$) than Alloy 79 (high, $$$$).
30Q130Choose 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.
30Q130 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
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Vickers
Reduction in Area
Charpy V-Notch Impact (RT)
Hardness, Rockwell B
Same in both: Poisson's Ratio 0.3
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)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Galvanic Potential (seawater, vs SCE)
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)
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 | 30Q130 | Alloy 79 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
30Q130 vs Alloy 79 — frequently asked
Is 30Q130 stronger than Alloy 79?
Yes. 30Q130 has a typical yield strength of 315 MPa (45.7 ksi) against 270 MPa (39.2 ksi) for Alloy 79 — about 17% more. Tensile strength is 345 MPa (50 ksi) vs 550 MPa (79.8 ksi).
Which is cheaper, 30Q130 or Alloy 79?
30Q130 is the lower-cost material: it sits in the standard tier ($$) while Alloy 79 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, 30Q130 or Alloy 79?
30Q130. Its machinability rates fair (40/100) against poor (32/100) for Alloy 79; for welding the order is Alloy 79 first (good, 60/100) then 30Q130 (fair, 35/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 30Q130 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.