| Material | Density g/cm3 | Yield MPa | Tensile MPa | Modulus GPa | Specific yield MPa per g/cm3 | Thermal W/m.K | Expansion um/m.K | Max temp |
|---|---|---|---|---|---|---|---|---|
| 6061-T6 Plates, housings, motor mounts, heat sinks. The default. | 2.70 | 276 | 310 | 68.9 | 102.2 | 167 | 23.6 | 150 C |
| 7075-T6 Arm clamps, landing gear, hinges, lugs. Not weldable. | 2.81 | 503 | 572 | 71.7 | 179 | 130 | 23.6 | 150 C |
| 2024-T3 Fatigue loaded fittings. Poor corrosion resistance, always coated. | 2.78 | 345 | 483 | 73.1 | 124.1 | 121 | 23.2 | 150 C |
| Titanium Grade 2 Standoffs, shims, corrosion critical brackets. | 4.51 | 275 | 345 | 105 | 61 | 16.4 | 8.6 | 300 C |
| Titanium Grade 5, Ti-6Al-4V Small highly loaded fittings, hot zones, composite joints. | 4.43 | 880 | 950 | 113.8 | 198.6 | 6.7 | 8.6 | 400 C |
| Stainless 304 Pins, shafts, dry wear parts. Heavy for flight structure. | 8.00 | 215 | 505 | 193 | 26.9 | 16.2 | 17.3 | 500 C |
| Stainless 316 Anything wetted by spray, fertiliser or salt. | 8.00 | 205 | 515 | 193 | 25.6 | 16.3 | 16.0 | 500 C |
| Brass C360 Contacts, bushings, RF hardware. Machines fastest of all. | 8.49 | 124 to 310 | 338 to 469 | 97 | 14.6 | 115 | 20.5 | 200 C |
| Copper C110 Spreaders under hot components. Heavy, so keep it small. | 8.94 | 69 to 365 | 220 to 455 | 117 | 7.7 | 391 | 17.0 | 200 C |
| POM, acetal Bushings, sleeves, isolator seats, non conductive spacers. | 1.41 | 65 to 72 | 65 to 72 | 3.1 | 46.1 | 0.31 | 110 | 90 C |
| PA66, nylon Feet, skids, bumpers. Absorbs moisture and grows with it. | 1.14 | 75 to 85 dry | 75 to 85 dry | 3.0 | 65.8 | 0.25 | 85 | 100 C |
| PEEK Thermal breaks, insulators next to motors and ESCs. | 1.32 | 95 to 100 | 95 to 100 | 3.7 | 72 | 0.25 | 47 | 250 C |
| PTFE Sliding and sealing only. Creeps under load, never structural. | 2.16 | 20 to 30 | 20 to 30 | 0.5 | 9.3 | 0.25 | 135 | 260 C |
Typical published values for the alloy or polymer, rounded. They describe the material, not your lot, and they are not a guarantee for a specific part. The number that applies to a real part is on its mill certificate, which travels with every order. Polymer values are for unfilled grades at room temperature and drop with temperature and moisture.
How to read this for a UAV part
Specific yield, not yield
Strength per unit of density is what matters when weight is the constraint. It is why titanium only beats 7075 by a small margin, and why the decision is usually about heat or corrosion rather than strength.
Modulus decides stiffness
All aluminium alloys have almost the same stiffness. A flexing plate is not fixed by a stronger alloy, it is fixed by a rib, a thicker web or a different section.
Thermal conductivity
6061 moves heat noticeably better than 7075, and every polymer here is an insulator. That single column decides heat sinks, motor mounts and thermal breaks.
Expansion matters at fits
Polymers move several times more than aluminium. A POM sleeve that fits an aluminium bore at 20 C may not at 60 C, so close plastic to metal fits need a stated temperature.
Max temperature is practical, not absolute
Aluminium loses strength well before it melts. If a part sits near a combustion engine or a hot ESC, measure the real temperature before choosing.
Density is only half the weight story
A stronger material lets the section shrink. Swapping alloys without changing geometry saves nothing, because both aluminium alloys weigh the same.
Guides that use this table
What we keep on the shelf
6061, 7075, titanium Grade 2 and 5, stainless 304 and 316, brass, copper, tool steel, POM, PA66, PEEK and PTFE. Anything else is bought to your drawing with the mill certificate attached, which adds lead time and nothing else.
Not sure which one your part wants?
Send the model, the load and the environment. We will say which material we would cut it from and why, and quote it two ways if the answer is close. Reply within 24 business hours.