Ti-6Al-4V Titanium vs C3604 Brass: which one fits your part
Ti-6Al-4V Titanium is the standard titanium alloy, with aluminium and vanadium, used where weight and corrosion matter. It is used for aerospace structures, medical implants and high performance parts. This entry explains what it is, what the numbers on a data sheet mean, and what to put on a drawing.
It is written from the point of view of the buyer and the drawing office: the values that are realistic in production, the ones that cost money, and the way the result is verified. Where an industry sets the requirement, food processing is used as the example: surfaces that clean down between production runs.
The short answer
Ti-6Al-4V Titanium and C3604 Brass overlap, but they are not interchangeable. Choose Ti-6Al-4V Titanium when the requirement is aerospace structures, medical implants and high performance parts; choose C3604 Brass when the requirement is fittings, connectors and turned components where machinability drives the cost.
Side by side
| Point of comparison | Ti-6Al-4V Titanium | C3604 Brass |
|---|---|---|
| What it is | the standard titanium alloy, with aluminium and vanadium, used where weight and corrosion matter | a free cutting brass with lead, the standard choice for turned parts that have to be fast to make |
| Used for | aerospace structures, medical implants and high performance parts | fittings, connectors and turned components where machinability drives the cost |
| Typical tolerance | ±0.01 mm | ±0.01 mm |
| Surface finish | Ra 0.8 µm achievable | Ra 0.8 µm achievable directly from the tool |
| Cost driver | material cost and slow cutting speeds | material cost is moderate, and the cycle time is the lowest of any metal |
Which one fits your part
Work from the feature that has to work. If the requirement is aerospace structures, medical implants and high performance parts, Ti-6Al-4V Titanium is the safer call; if it is fittings, connectors and turned components where machinability drives the cost, C3604 Brass wins on cost or on lead time. Where the drawing does not make it clear, that is the question to settle before quotation rather than after.
A note on specification
Write the drawing so that either route can be considered where the function allows. That keeps the quotation competitive and stops a process being specified where a result should have been.
Applications
Ti-6Al-4V Titanium is used for aerospace structures, medical implants and high performance parts, and in practice it appears most often in aerospace brackets, implants and trials, motorsport components, marine hardware.
How it fits into a machining route
Ti-6Al-4V Titanium is chosen at the drawing stage, and everything downstream follows from it: the tool geometry, the cutting data, the heat treatment and the certificate. Changing the grade later is a different part, not a different quote.The route is fixed before the first part is cut, and it is the route rather than the individual setting that holds the result: material cost and slow cutting speeds. Where a drawing calls for something the route cannot hold economically, that is raised at quotation rather than after the parts are made.
Standards, documentation and what is issued
The documentation requirement is AS9100 with material traceability. Material is supplied against a certificate where the application calls for it, inspection results are recorded with the job, and the records are kept so that a repeat order can be compared with the first instead of being measured from scratch.
Dimensional inspection with a certificate check is the verification step. Where a customer format or a standard report is required, it is agreed before the batch starts, because a report written after the event is a report nobody can use.
Frequently asked questions
What tolerance should be specified for Ti-6Al-4V Titanium?
±0.01 mm is realistic in production. Tightening it beyond the functional requirement increases cost without improving the part.
Which material is usually used?
Ti-6Al-4V titanium is the usual choice, supplied against AS9100 with material traceability.
How is the result verified?
Dimensional inspection with a certificate check, with the results recorded so a repeat order can be compared with the first.
What is the most common mistake?
Allowing chips to re-cut, because titanium chips are hard and angular.
How long does it take and what does it cost?
A realistic cycle is slow cutting with a low speed and a high feed, and the cost driver is material cost and slow cutting speeds.
Related capability
If you are specifying Ti-6Al-4V Titanium on a drawing and want a second opinion on the route, send the model and the quantity. The first response is a manufacturability review with the likely risk points and a quotation, so the decision can be made on facts rather than on a price alone.
Machining, inspection and documentation are handled in one place, which is why the dimensional report and the material certificate arrive with the parts rather than after them.
Related entries
These entries sit next to Ti-6Al-4V Titanium in the encyclopedia: C3604 Brass, Duplex 2205 Stainless Steel, Mould Inserts. Reading them together gives a fuller picture of how the process, the material and the measurement affect each other.
