Standard Specification for Unalloyed Titanium for Surgical Implant Applications (UNS R50250, R50400, R50550, R50700)
ASTM F67 covers commercially pure (CP) unalloyed titanium bar, wire, rod, and forging stock for surgical implants, such as:
Orthopedic implants
Dental implants
Trauma hardware
Spinal components
This standard ensures biocompatibility, high corrosion resistance, and suitable mechanical properties for medical use.
Product Forms
Supplied in the form of:
Bar
Wire
Rod
Forging stock
Dimensions and tolerances are specified by:
Customer requirements
ASTM F136 / ASTM B348 dimensional guidance (for bar/rod)
Grades and Chemical Composition
ASTM F67 includes four grades of CP titanium, corresponding to different purity levels:
|
Grade |
UNS No. |
Oxygen Content |
Yield Strength (min) |
Comments |
|
Gr 1 |
R50250 |
≤ 0.18% |
240 MPa (35 ksi) |
Softest, most ductile |
|
Gr 2 |
R50400 |
≤ 0.25% |
345 MPa (50 ksi) |
Balance of strength/ductility |
|
Gr 3 |
R50550 |
≤ 0.35% |
450 MPa (65 ksi) |
Higher strength |
|
Gr 4 |
R50700 |
≤ 0.40% |
550 MPa (80 ksi) |
Strongest CP grade |
Other elements (max limits):
|
Element |
Limit (%) |
|
N (Nitrogen) |
≤ 0.03 |
|
H (Hydrogen) |
≤ 0.015 |
|
C (Carbon) |
≤ 0.10 |
|
Fe (Iron) |
≤ 0.50 |
|
O (Oxygen) |
Varies by grade (above) |
|
Ti (Titanium) |
Remainder |
Mechanical Properties (Annealed Condition)
|
Grade |
Tensile Strength (min) |
Yield Strength (min) |
Elongation (%) |
Area Reduction (%) |
|
Gr 1 |
240 MPa (35 ksi) |
170 MPa (25 ksi) |
≥ 24 |
≥ 30 |
|
Gr 2 |
345 MPa (50 ksi) |
275 MPa (40 ksi) |
≥ 20 |
≥ 30 |
|
Gr 3 |
450 MPa (65 ksi) |
380 MPa (55 ksi) |
≥ 18 |
≥ 30 |
|
Gr 4 |
550 MPa (80 ksi) |
483 MPa (70 ksi) |
≥ 15 |
≥ 25 |
Microstructure and Metallurgy
Product must be uniform in microstructure and free from:
Inclusions
Voids
Cracks
Alpha-case
Typically supplied in the annealed condition
May be inspected by optical microscopy or ultrasonic testing for flaws
Surface Finish and Cleaning
Surface must be free from scale, cracks, pits, and foreign matter
Cleaning usually per ASTM B600
Optional pickling or abrasive finishing
Testing and Certification
Chemical analysis: Verified per ASTM E539 / E1447
Tensile testing: Per ASTM E8
Microstructural exam: If required
NDT (Ultrasound, FPI): For high-integrity implants
MTR (Mill Test Report): Required with:
Heat number
Mechanical test results
Chemical composition
Product form and condition
Biocompatibility and Usage
Titanium under ASTM F67 is biocompatible due to:
High corrosion resistance (forms passive oxide film)
Absence of toxic or allergic elements (e.g., Ni, Co, Cr)
Common implant uses:
Bone plates, screws, nails
Dental implant fixtures
Spinal cages and rods
Heart valve components
Cranial and maxillofacial devices
Related Standards
ASTM F136: Ti-6Al-4V ELI for implants (alloyed titanium)
ASTM F1295: Ti-6Al-7Nb alloy for implants
ASTM B348: General bar/rod specification
+86-731-82224155
8613272400394
enquiry@jetvisiontitanium.com