Aluminum A380 vs Magnesium Alloy AZ91D
Cross-family material comparison
Aluminum A380 is an aluminum grade and Magnesium Alloy AZ91D is a magnesium alloy grade — different families, so density, stiffness and cost move together with strength. A380 is the stronger of the two: tensile strength 324 MPa (47 ksi) against 230 MPa (33.4 ksi) for AZ91D, about 41% more. A380 is the more ductile: elongation 3.5% versus 3% for AZ91D, and A380 is harder (80 HB vs 63 HB). AZ91D is lighter (1.81 g/cm³ vs 2.76 g/cm³ for A380) and A380 is stiffer (71 GPa vs 45 GPa). On the shop floor, AZ91D machines more easily (excellent vs very good), AZ91D welds better (fair vs poor), and A380 sits in a lower cost tier (budget, $) than AZ91D (standard, $$).
A380Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
AZ91DChoose it when weight is the constraint, or when the part is machined in volume.
A380 vs AZ91D: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all grades of the two families 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 grades of the two families 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
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Compressive Strength
Hardness, Vickers
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Same in both: Liquidus Temperature 595°C1,103 °F
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).
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
Machinability Rating (AISI 1212 = 100 %)
Same in both: Castability 92 / 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
Thermal Shock Resistance Index
Strength versus weight
Yield strength against density for every grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | A380 | AZ91D |
|---|---|---|
| Default condition | — | As Cast |
| Relative cost | $ Budget | $$ Standard |
| Min. machined wall | 1 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 0.8 µm |
| Cerakote | Yes | — |
| DLC | Yes | — |
| Electroless Nickel (EN) | Yes | — |
| Electropolishing | Yes | — |
| Epoxy Coating | Yes | — |
| Gold Plating | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Silver Plating | Yes | — |
Both are offered for CNC machining and Casting & forging. They share 7 finishes: Anodizing Type II, Chem Film (Alodine), E-Coating, Hard Anodize Type III w/ PTFE, Hard Anodizing Type III, Painting, Powder Coating.
A380 vs AZ91D — frequently asked
Is A380 stronger than AZ91D?
Yes. A380 has a typical tensile strength of 324 MPa (47 ksi) against 230 MPa (33.4 ksi) for AZ91D — about 41% more.
Which is cheaper, A380 or AZ91D?
A380 is the lower-cost material: it sits in the budget tier ($) while AZ91D is standard ($$). 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, A380 or AZ91D?
AZ91D. Its machinability rates excellent (98/100) against very good (70/100) for A380; for welding the order is AZ91D first (fair, 40/100) then A380 (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in A380 and AZ91D 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.