Aluminum 7003 vs 7178
Aluminum · grade comparison
Aluminum 7003 and 7178 are both aluminum grades. 7178 is the stronger of the two: yield strength 538 MPa (78 ksi) against 315 MPa (45.7 ksi) for 7003, about 71% more; tensile strength follows at 607 MPa (88 ksi) vs 360 MPa (52.2 ksi). 7178 is harder — 160 HB against 105 HB for 7003 — which matters for wear surfaces and threads. 7003 conducts heat better (150 W/m·K vs 125 W/m·K). On the shop floor, 7003 welds better (very good vs not recommended), 7003 forms better (fair vs poor), and 7003 sits in a lower cost tier (standard, $$) than 7178 (premium, $$$).
7003Choose it when it will be welded, or when cost is the deciding factor.
7178Choose it when strength drives the design, or when surface hardness matters.
7003 vs 7178: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum 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 aluminum 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
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Vickers
Same in both: Poisson's Ratio 0.33
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)
Same in both: Latent Heat of Fusion 390 J/g168 BTU/lb · Max Service Temperature (continuous) 120°C248 °F · Min Service Temperature -196°C-321 °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)
Brazeability / Solderability
Same in both: Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Water
Typical Recycled Content
Same in both: Embodied Energy (primary production) 205 MJ/kg88,134 BTU/lb · Embodied Carbon (primary production) 12.5 kg CO₂/kg
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 aluminum grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 7003 | 7178 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$$ Premium |
| Min. machined wall | 0.5 mm | 0.5 mm |
| Best machined surface | Ra 0.8 µm | Ra 0.8 µm |
Both are offered for CNC machining and Sheet metal. Both take the same 16 finishes: Anodizing Type II, Cerakote, Chem Film (Alodine), DLC, E-Coating, Electroless Nickel (EN), Electropolishing, Epoxy Coating, Gold Plating, Hard Anodize Type III w/ PTFE, Hard Anodizing Type III, Nickel Plating and 4 more.
7003 vs 7178 — frequently asked
Is 7178 stronger than 7003?
Yes. 7178 has a typical yield strength of 538 MPa (78 ksi) against 315 MPa (45.7 ksi) for 7003 — about 71% more. Tensile strength is 607 MPa (88 ksi) vs 360 MPa (52.2 ksi).
Which is cheaper, 7003 or 7178?
7003 is the lower-cost material: it sits in the standard tier ($$) while 7178 is premium ($$$). 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, 7003 or 7178?
7178. Its machinability rates very good (72/100) against good (65/100) for 7003; for welding the order is 7003 first (very good, 75/100) then 7178 (not recommended, 12/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 7003 and 7178 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.