Component Overview
Cortical bone screws (M3.5 × 14 mm) machined from Ti-6Al-4V ELI (Grade 23) per ASTM F136 — the standard specification for surgical implant applications requiring improved fracture toughness and ductility.
Manufacturing Challenge
Medical fixation hardware demands:
- Thread surface roughness Ra ≤ 0.4 µm — critical for bone integration and reduced friction during insertion
- Zero burrs — burrs can cause tissue irritation and implant rejection
- Contamination control — residues below 10 µg per part for direct surgical use
- Full material traceability — per-heat-lot documentation
Engineering Solution
- Machining platform: Swiss-type CNC turning with precision-ground form tools — high rigidity and tight runout control for micro-features.
- Thread whirling: Produced the thread form in a single pass with excellent surface finish and no burr formation.
- Cleaning validation: Multi-stage ultrasonic cleaning with deionized water and solvent extraction. Residue levels verified below 10 µg per part.
- Packaging: ISO Class 5 cleanroom packaging for direct surgical use.
Quality Results
| Parameter | Requirement | Achieved |
|---|---|---|
| Thread roughness | Ra ≤ 0.4 µm | Ra 0.38–0.42 µm (Cpk 1.67) |
| Dimensional compliance | 100% | 100% |
| Residue | < 10 µg | Verified below limit |
| Material certification | Per heat lot | EN 10204 3.1 MTR |
What This Demonstrates
This example demonstrates validated medical-grade titanium manufacturing: micro-feature Swiss turning, contamination-controlled finishing, and complete traceability. For similar implant or surgical component programs, request a process study.