Young's Modulus of Aluminium Alloy 6061
| Value | 6.89e10 Pa |
| Status | Measured: ± 1,500,000,000 Pa (0.022 relative) |
| Source | Aluminum Design Manual (The Aluminum Association) |
| Categories | Material PropertiesEngineering & Trade |
| microbar | 689,000,000,000 μbar |
| barye | 689,000,000,000 Ba |
| millitorr | 516,792,500,000 mTorr |
| pascal | 68,900,000,000 Pa |
| millimeter of water column | 7,025,844,700 mmH₂O |
| pound per square foot | 1,439,006,400 lb/ft² |
| centimeter of water column | 702,584,470 cmH₂O |
| hectopascal | 689,000,000 hPa |
| millibar | 689,000,000 mbar |
| torr | 516,792,500 Torr |
| millimeter of mercury | 516,792,430 mmHg |
| inch of water column | 276,608,060 in w.g. |
| kilopascal | 68,900,000 kPa |
| foot of water column | 23,050,672 ft H₂O |
| inch of mercury | 20,346,158 inHg |
| pound per square inch | 9,993,100.1 psi |
| meter of water column | 7,025,844.7 m H₂O |
| decibar | 6,890,000 dbar |
| kilogram-force per square centimeter | 702,584.47 kgf/cm² |
| bar | 689,000 bar |
| atmosphere | 679,990.13 atm |
| megapascal | 68,900 MPa |
| kip per square inch | 9,993.1001 ksi |
| gigapascal | 68.9 GPa |
| million pounds per square inch | 9.9931001 Mpsi |
Learning zone
Ten thousand ksi is the number every aluminium designer carries, and like steel's 29 000 ksi it is essentially alloy-independent: 6061-T6, 6063-T5 and 5052-H32 all sit within a couple of percent of 69 GPa, and even 7075-T6, which is three times stronger than 6061-O, is only 71.7 GPa. Temper changes strength, not stiffness.
The ratio to steel — very nearly 1:3 — drives the design of every aluminium structure. Substituting an aluminium section for an identical steel one triples the deflection and cuts the Euler buckling load to a third, while cutting the weight to about 35 %. That is why aluminium extrusions are deep and ribbed: geometry has to buy back the stiffness the material does not have. Aluminium also has no fatigue endurance limit, so cyclically loaded aluminium is designed to a finite life, and it loses strength fast above about 150 °C — near a weld, the heat-affected zone of 6061-T6 reverts toward annealed properties and is designed as such.