医療機器のCNC加工：2026年ガイド（ISO 13485、材料、生体適合性）
医療機器CNC加工のエンジニアガイド：インプラント級材料、ISO 13485とFDA・ISO 10993、公差、交差汚染、トレーサビリティ、部品タイプ。
医療機器部品の加工は、30%が金属切削、70%が「正しく行った」ことの証明です。公差は厳しく、材料は扱いにくく、そして文書化 — ISO 13485、生体適合性、完全なトレーサビリティ — こそが医療サプライヤーと一般加工工場を分けます。本ガイドは両面を扱います：部品を成す材料と公差、そして多くの記事が見落とす交差汚染の罠を含むコンプライアンスの現実です。
What makes medical machining different
Implant & device-grade materials
Medical materials are specified by exact standard, not just alloy name. "Titanium" isn’t a spec; "Ti-6Al-4V ELI per ASTM F136" is. The grade, standard and lot must all be documented.
| Material | Typical spec | Where it’s used | Guide |
|---|---|---|---|
| Titanium Ti-6Al-4V ELI | ASTM F136 | Implants, bone screws, spinal hardware | Titanium guide |
| CP Titanium (Grade 2/4) | ASTM F67 | Dental, non-load implants | Titanium guide |
| Stainless 316L | ASTM F138 | Surgical instruments, trauma hardware | Stainless guide |
| Cobalt-chrome (CoCr) | ASTM F75/F1537 | Articulating joint surfaces | — |
| PEEK (implant grade) | ISO 10993 / USP VI | Radiolucent spinal cages, trauma | PEEK guide |
| Aluminium / 303 SS | — | Non-implant device housings, enclosures | Aluminium guide |
ISO 13485, FDA & ISO 10993 — what each covers
Three different things get conflated as "medical certified". They cover different bases, and you usually need more than one.
ISO 13485
- What: the quality-management system standard for medical-device manufacturing.
- Governs process control, validation, documentation and traceability.
- This is the certification a medical machine shop must hold.
FDA / 21 CFR 820
- What: US regulatory requirements (Quality System Regulation) for devices sold in the USA.
- Overlaps heavily with ISO 13485 but is a legal regulation, not a certification.
- Relevant to the device maker; the supplier supports it with documentation.
ISO 10993
- What: biological evaluation — biocompatibility testing of materials.
- Ensures the material (and how it was processed) is safe for the body.
- This is where cross-contamination bites — see below.
The cross-contamination trap
This is the medical-machining failure mode that general shops don’t see coming. A CNC machine that previously cut brass or copper alloys can leave microscopic traces on the next part. On an ordinary component, nobody cares. On a titanium implant, those copper traces can fail ISO 10993 biocompatibility testing — and the whole lot is scrap.
- Dedicated or validated-clean tooling, collets and fixtures for implant materials.
- Segregated or flushed coolant to avoid carry-over from other jobs.
- Documented cleaning between material types, recorded in the traveller.
- Deburring and passivation processes that don’t introduce contaminants.
Tolerances & surface integrity
Medical parts combine tight dimensional tolerance with something general machining rarely tracks: surface integrity. A bone screw that’s dimensionally perfect but has a work-hardened, micro-cracked surface can fail in fatigue inside the body. We control both.
| Attribute | Capability | Note |
|---|---|---|
| Critical tolerance | ±0.005 mm | Swiss turning for the tightest small features |
| Surface finish Ra | ≤0.2 µm | Fine finish + polishing/electropolishing |
| Surface integrity | Controlled | Avoid work-hardened white layer on Ti |
| Threads | Class 3 | Bone-screw and instrument threads |
| Small-feature work | sub-mm | Routed to micro-machining |
Small, slender medical parts — bone screws, pins, dental posts — are ideal for Swiss-type turning; see our Swiss machining guide and micro-machining service. Tolerance specification is covered in our GD&T guide.
Parts we machine for medical
- Implants: bone screws, plates, spinal cages, dental abutments in Ti ELI, CoCr and PEEK.
- Surgical instruments: handles, shafts, cutting-guide bodies, drill guides in 316L / 465 stainless.
- Device housings & enclosures: diagnostic and monitoring equipment in aluminium and stainless.
- Micro components: endoscopic and minimally-invasive parts via micro-machining.
Traceability & documentation
For a medical part, the documentation IS part of the deliverable. Your device history file needs a paper trail from raw bar to finished, inspected part. Under ISO 13485 we provide:
- Material certificate of conformance with the exact spec (e.g. ASTM F136) and heat-lot number.
- Full lot traceability — material lot, machine, operator, dates linked to each part or batch.
- CMM inspection reports and first-article inspection (FAI) documentation.
- Certificate of conformance for the finished part.
- Process records for controlled operations (deburr, passivation, cleaning).
- Our quality control department manages this documentation package on every medical order.
Design for medical machining
For the broader design rules that also cover aerospace, see our aerospace & medical DFM checklist. Ready to start? Send your drawings for a quote and DFM review.
Frequently asked questions
The questions device engineers and buyers ask most about medical CNC machining.
よくあるご質問
- The core requirement is a certified ISO 13485 quality-management system, which governs process control, validation, documentation and traceability for medical devices. Depending on the market, the supplier also supports FDA 21 CFR 820 (US Quality System Regulation) compliance, and provides materials that meet ISO 10993 biocompatibility. ISO 13485 is the certification to look for first.
- The most common implant materials are titanium Ti-6Al-4V ELI (ASTM F136), CP titanium (ASTM F67), cobalt-chrome (ASTM F75/F1537) for joint surfaces, and implant-grade PEEK for radiolucent spinal and trauma parts. Surgical instruments typically use 316L or 465 stainless (ASTM F138). Each must be specified by its exact standard and fully traceable.
- A CNC machine that previously cut brass or copper alloys can leave microscopic heavy-metal traces on the next part. On an implant, those traces can fail ISO 10993 biocompatibility testing and scrap the lot. Preventing it requires a documented decontamination protocol — dedicated or validated-clean tooling, fixtures and coolant, with cleaning recorded between material types. Always confirm your supplier has this protocol.
- We hold ±0.005 mm on critical features, with Swiss-type turning for the tightest small components like bone screws and pins, and surface finishes to Ra 0.2 µm or finer with polishing/electropolishing. Beyond dimensions, we control surface integrity — avoiding the work-hardened, micro-cracked layer on titanium that can cause fatigue failure inside the body.
- Under ISO 13485 you receive a material certificate of conformance with the exact spec and heat-lot number, full lot traceability (material, machine, operator, dates), CMM inspection and first-article inspection reports, a certificate of conformance for the finished part, and process records for controlled operations. This package supports your device history file.
- Yes. We machine implant-grade titanium, CoCr and PEEK for implants and instruments under ISO 13485 with cross-contamination control, as well as non-implant device housings and enclosures in aluminium and standard stainless. Separating implant from non-implant parts on the drawing lets us apply implant-grade rigor (and cost) only where it’s actually required.
What certifications does a medical CNC machining supplier need?
Which materials are used for medical implants?
What is the cross-contamination risk in medical machining?
How tight are tolerances for medical parts?
What documentation comes with a medical part?
Can you machine both implants and device housings?
Recommended services
Move from research to a quote in one click.
関連記事
著者について
JLYPT Engineering Team
Medical & Precision Machining Engineers
We machine implant-grade titanium, 316L stainless and medical PEEK for device makers who live and die by ISO 13485, biocompatibility and traceability. This guide is the compliance-and-manufacturing discipline our team applies so medical parts pass inspection and audit the first time.
類似プロジェクトのお見積りが必要ですか？
CAD ファイルをアップロードしていただければ、エンジニアが 24 時間以内に返信します。
無料見積りを依頼