Shenzhen Alu Rapid Prototype Precision Co., Ltd.
Industry News
Short answer: Aerospace CNC work depends less on the machine and more on documentation and control: material traceability, first-article inspection (AS9102), and a quality system such as AS9100. Typical tolerances are ±0.02–0.05 mm, with tight features at ±0.01 mm, and the most common materials are 7075 and 2024 aluminum, Ti-6Al-4V, 17-4 PH, and Inconel.
Why Aerospace Machining Is Different
A part that looks identical to a commercial part costs more in aerospace because of what surrounds it: certifiable material, controlled processes, documented inspection, and full traceability from raw stock to finished part. Certification is the product; the machining is the delivery mechanism.
Common Aerospace Materials
| Material | Why it is used | Machining notes |
|---|---|---|
| Aluminum 7075-T6 / T7351 | Highest strength aluminum, good fatigue life | Machines well; needs anodizing; T7351 resists SCC |
| Aluminum 2024 | Excellent fatigue and fracture toughness | The benchmark for aircraft skins; not weldable |
| Titanium Ti-6Al-4V | Strength-to-weight plus temperature capability | Slow cutting, tool wear, work-hardening |
| Stainless 17-4 PH | High strength with corrosion resistance | Heat treat after machining; dimension control matters |
| Stainless 15-5 PH | Similar to 17-4 with better toughness | Good for structural and valve components |
| Inconel 718 | High-temperature strength, oxidation resistance | Very difficult to machine; requires rigid setups and sharp tooling |
| Magnesium alloys | Very low density | Fire risk in machining; specialist handling |
Tolerances and Surface Finish
| Feature | Typical aerospace requirement |
|---|---|
| General dimensions | ±0.05 mm |
| Critical features | ±0.02 mm |
| Precision fits and bores | ±0.01 mm |
| Surface finish | Ra 0.8–1.6 µm typical |
| Position tolerance | Often specified with GD&T per ASME Y14.5 |
| Burr control | All edges deburred; specified in the drawing |
GD&T is the norm rather than the exception, and features are usually referenced to datums rather than to each other.
Certifications That Matter
| Standard | What it covers |
|---|---|
| AS9100 | The aerospace quality management system (ISO 9001 + aerospace requirements) |
| AS9102 | First Article Inspection reporting |
| NADCAP | Special-process accreditation (heat treat, NDT, chemical processing, coatings) |
| ITAR | US export control for defense-related work |
| Material certs | Mill certificates with heat/lot traceability |
Inspection and Documentation
Expect, and require:
Mill material certificates traceable to the heat number
CMM dimensional reports against the drawing
AS9102 first article inspection report for new parts
Process certifications for heat treat, anodizing, and NDT where applicable
Serial or lot traceability on the finished parts
Certificates of conformity (CoC) with each shipment
Design Considerations
Avoid sharp internal corners — they concentrate stress and require small cutters
Plan for anodizing build-up on fits and bores; specify masking where needed
Minimize thin walls — they vibrate and distort under cutting loads
Consider fatigue — surface finish and edge condition drive crack initiation
Keep the drawing unambiguous — a clear GD&T scheme prevents costly disputes
See our CNC machining capabilities and our aerospace industry page for what we hold as standard.
FAQ
What does AS9100 certification mean?
It is the aerospace quality management standard, based on ISO 9001 with additional requirements for traceability, risk management, and process control.
What is first article inspection (FAI)?
A full dimensional and documentation verification of the first production part, reported per AS9102, confirming the process produces conforming parts.
Which aluminum is best for aerospace?
7075 for strength, especially in the T7351 temper to resist stress corrosion cracking; 2024 where fatigue and fracture toughness dominate.
Why is aerospace machining more expensive?
Certified material, tighter tolerances, full inspection, and documentation add cost beyond the machining itself.
Can you machine ITAR-controlled parts?
This depends on the supplier's registration and location. Confirm ITAR status before sharing controlled drawings.
Request a Quote
Send your drawing and tell us the certification and inspection requirements. We will confirm capability before quoting.