Density of Aluminium Alloy 6061
| Value | 2,700 kg/m³ |
| Status | Measured: ± 20 kg/m³ (0.0074 relative) |
| Source | ASM Handbook, Vol. 2: Properties of Nonferrous Alloys |
| Categories | Material PropertiesEngineering & Trade |
| microgram per liter | 2,700,000,000 μg/L |
| milligram per cubic meter | 2,700,000,000 mg/m³ |
| milligram per liter | 2,700,000 mg/L |
| pound per cubic yard | 4,550.9983 lb/yd³ |
| kilogram per cubic meter | 2,700 kg/m³ |
| gram per liter | 2,700 g/L |
| pound per cubic foot | 168.55549 lb/ft³ |
| pound per imperial gallon | 27.060515 lb/imp gal |
| pound per US gallon | 22.532592 lb/gal |
| slug per cubic foot | 5.2388649 slug/ft³ |
| gram per cubic centimeter | 2.7 g/cm³ |
| gram per milliliter | 2.7 g/mL |
| kilogram per liter | 2.7 kg/L |
| tonne per cubic meter | 2.7 t/m³ |
| US short ton per cubic yard | 2.2754992 ton/yd³ |
| pound per cubic inch | 0.097543688 lb/in³ |
Learning zone
Pure aluminium is 2698 kg/m³ and the common wrought alloys sit within a percent of it: 6061 at 2700, 5052 at 2680, 7075 at 2810 because of the zinc. The number every designer actually uses is the ratio — aluminium is roughly one third the weight of steel, so a section of identical geometry weighs a third as much. That is the whole argument for aluminium ladders, truck bodies and heat sinks.
The trap is finishing the sentence there. Aluminium's stiffness is also about one third of steel's (69 GPa against 200 GPa), so an identical section is three times as flexible. Equal-weight aluminium members have to be made deeper or thicker to match stiffness, which is why aluminium structures look chunky. Weight advantage is real; stiffness advantage is not, and deflection rather than strength usually governs the redesign.