Guides / Materials
Titanium Grade 5 on a UAV: the parts where it is worth the money
September 20, 2026
Titanium Grade 5, or Ti-6Al-4V, is the alloy people reach for when 7075 is not enough. It is also the alloy people waste money on, because the reason to use it is narrow and the cost is not. Titanium is one of the options compared in our guide to drone parts materials.
Here is when it pays on an unmanned aircraft, and when it does not.
What you actually get
| Property | 7075-T6 aluminium | Ti-6Al-4V | What it means |
|---|---|---|---|
| Yield strength | about 503 MPa | about 880 MPa | A titanium fitting carries the same load in a smaller section |
| Density | 2.81 g/cm3 | 4.43 g/cm3 | Titanium is heavier per unit of volume, by a lot |
| Strength to weight | about 179 | about 199 | Better, but not dramatically |
| Elastic modulus | about 72 GPa | about 114 GPa | Stiffer per unit of section |
| Service temperature | falls off past 150 C | comfortable to 400 C | Decides anything near a combustion engine |
| Galvanic behaviour with carbon | poor, needs isolation | close to carbon, mild | Decides composite joints |
Read the strength to weight line carefully. Titanium beats 7075 by roughly ten percent on that measure. That is not the reason to use it. The reasons are the last three lines.
Where titanium earns its place
Small highly loaded fittings. A clevis, a shackle, a hinge pin, a lug carrying concentrated load. These parts are strength limited rather than stiffness limited, so the extra yield lets the section shrink. A 12 gram aluminium lug that becomes a 9 gram titanium lug is a real saving because the part was small and dense to begin with.
Anything hot. Hybrid aircraft with a small combustion engine have brackets, standoffs and exhaust hangers sitting in air that aluminium should not be in. Aluminium loses a significant fraction of its strength above 150 C. Titanium does not care until much higher.
Composite joints. Aluminium bolted directly to carbon fibre is a galvanic cell. Carbon sits near the noble end of the series, aluminium near the active end, and the difference of roughly one volt is enough to corrode the aluminium quickly once salt or rain gets in. Titanium sits much closer to carbon, so a titanium fitting in a carbon structure is the low maintenance answer. There is more in aluminium against carbon fibre.
Fasteners and threaded parts in thin structure. Titanium threads hold up better than aluminium threads under repeated assembly, which matters on a part a technician opens in the field.
Where it is the wrong answer
- Plates and chassis. These are stiffness driven. Titanium is stiffer per unit of section but denser, and the geometry usually wins anyway. A pocketed 6061 plate is lighter and a quarter of the price.
- Housings and covers. Nothing about a housing needs 880 MPa.
- Heat sinks. Titanium conducts heat about one twentieth as well as aluminium. It is close to the worst possible choice.
- Anything you have not weighed. If the part is not on the critical weight list, titanium is a way to spend money without flying longer.
Grade 5 or Grade 2
Grade 2 is commercially pure titanium. It is softer, cheaper, easier to machine and formable, with roughly a third of the yield strength of Grade 5. On a UAV it shows up as standoffs, spacers, shims and brackets that exist for corrosion reasons rather than load reasons. If the part carries a real load, it is Grade 5.
Specify the standard as well as the grade. ASTM B348 covers bar and billet, ASTM B265 covers plate and sheet. A mill certificate against one of those ties the material in your part to a number you can check.
Machining reality, so the quote makes sense
Titanium is not hard to machine, it is slow and unforgiving. Three things drive the cost:
- Cutting speed. Heat does not leave through the chip the way it does in aluminium, so surface speeds are a fraction of what an aluminium part runs at. The same geometry takes two to four times longer.
- Tool wear. Cutters wear faster and get changed more often. That cost sits in the part price whether it is itemised or not.
- Rigidity. Titanium springs back. Thin walls and long reaches that are routine in aluminium need lighter cuts, more passes and better fixturing.
None of this makes it exotic. It makes it a material where the geometry has to earn every feature. Deep pockets with small corner radii are expensive in aluminium and punishing in titanium, so open the radii out. The rules in designing machined drone parts for weight apply twice as hard here.
Finishing
Titanium does not need a coating to survive weather. Where it does get treated:
- Titanium anodising for colour coding and mild wear. It is a thin oxide, not the hard layer you get on aluminium.
- Passivation to clean the surface after machining.
- Laser marking, which works well and stays readable.
Do not specify hard anodise on a titanium part. That is an aluminium process, and asking for it on a drawing tells a shop the drawing has not been checked.
A short decision rule
Ask two questions about the part.
- Is it strength limited, hot, or bolted to carbon?
- Is it small?
If the answer to both is yes, quote it in titanium and in 7075 and compare cost per gram saved. If either answer is no, stay in aluminium and spend the money on a better battery.
Send the model and we will quote both. Price and lead time come back within 24 business hours, and the material list says what we keep on the shelf.
Frequently asked questions
Is titanium always lighter than aluminium?
No. Titanium Grade 5 is about 60 percent denser than aluminium, 4.43 against 2.81 grams per cubic centimetre. It saves weight only where the part can be made smaller because the material is stronger, which means highly loaded fittings, not plates or housings.
How much more does a titanium part cost to machine?
Expect two to four times the machining time of the same part in aluminium, plus a higher material price. Titanium cuts slowly, work hardens if the tool rubs and wears cutters quickly, so the cost is in the hours more than in the bar.
Does titanium solve the carbon fibre corrosion problem?
It reduces it a lot. Titanium sits close to carbon on the galvanic series, so a titanium fitting bolted to a carbon structure corrodes far less than an aluminium one. Aluminium against carbon needs an insulating layer, a sealant or a sacrificial part.
Need this part quoted?
Send the model and the quantity. Price and lead time come back within 24 business hours.